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PORT QUENDALL MITIGATION ANALYSIS MEMORANDUM Prepared for: RemediaEtion Technologies, Inc. 1011 K1ickitat Way, Suite 207 Seattle, Washington 98134 Prepared by: Beak Consultants incorporated 12931 N.E. 126th Place Kirkland, Washington 98034 19 June 1997 Project No. 22253 Port Quendal! Drat? Mitigation Analysis Memorandum TABLE OF CONTENTS a 1.0 INTRODUCTION.................................................... 1-1 1.1 Objectives ....................... .................... I......... 1-1 I 1.2 Disclaimer..................................................... 1-1 1.3 Remediation Alternative Summary Descriptions ....................... 1-2 2.0 DESCRIPTION OF AFFECTED RESOURCES ........................... 2-1 2.1 Water Quality ................................................... 2-1 2.2 Plants and Animals ............. . .............................. 2-13 2.3 Fisheries ......................... ............................ 2-19 2 3.1 Introduction ...... ....................................... 2-19 2.3.2 Lake Washington Biology .... ........... 2-19 2.3.3 Lake Washington Shoreline ................................. 2-24 2.3.4 Lake Washington Open Water ............................... 2-35 2.3.5 Habitat Valuation .. •..........:........................... 2-38 2.4 Recreational ................................................... 2-39 2.5 Cultural ...................................................... 2-39 2.6 Economic ..................................................... 2-39 S 3.0 IMPACTS .................................................... 3-1 3.1 Remediation Alternative I - Low Impact ............................. 3-1 3.1.1 Plants and Animals ........................................ 3-1 3.1.2 Fisheries ..... ............................................ 3-3 i 3.2 Remediation Alternative 2 - Medium Impact 3.2.1 Plants and Animals ........................................ 3-9 3.2.2 Fisheries ................................................. 3-9 19 June 1997 c.U221JtmWSau..pz Page i Port Quendall Draft Mitigation Analysis Memorandum TABLE OF CONTENTS (Continued) Rage 3.3 Rernediation Alternative 3 - High Impact ............................ 3-10 k 3.3.1 Plants and Animals ....................................... 3-10 3.3.2 Fisheries ................................................ 3-12 i 4.0 MITIGATION....................................................... 4-1 4.1 Remediation Alternative 1 - Low Impact ....... 4-1 4.1.1 Plants and Animals ......... ... . ......................... 4-1 4.1.2 Fisheries 4-10 4.2 Alternative 2 - Medium Impact .................................... 4-15 4.2.1 Mitigation ................................................ 4-15 4.2.2 Plants and Animals ......................... ............... 4-16 4.2.3 Fisheries ................................................ 4-16 4.3 Remediation Alternative 3 - High Impact ............................ 4-17 4.3.1 Mitigation ............................................... 4-17 4.3.2 Plants and Animals ......... . ............................. 4-20 4.3.3 Fisheries .... ............................................. 4-20 5.0 REFERENCES ....................... ............................... 5-1 APPENDIX A: Agency Correspondence Regarding Threatened, Endangered and Sensitive and Plant Species' E i i t 19 June 1997 c:Y2175Jknuf1Za(erp2 Page 11 Port Quendall Draf? Mitigation Analysis Memorandum LIST OF FIGURES Page Figure 1-1. Remediation Alternative 1 (low impact) ............................... 1-4 Figure 1-2. Remediation Alternative 2 (medium impact) ........................... 1-5 Figure 1-3. Remediation Alternative 3 (high impact) .............................. 1--6 Figure 2-1. METRO water quality sampling stations in Lake Washington ............. 2-2 Figure 2-2. Wetlands and shoreline vegetation ................................. 2-14 Figure 2-3. Aerial overview of Port Quendall Remediation Site . ................... 2-15 Figure 2-4. Lake Washington substrate off project site ........................... 2-22 Figure 2-5. 1994 beach seining results at Kennydale Park. ...... I ........... I ..... 2-25 Figure 2-6. Bank characteristics and protection features ........................... 2-28 Figure 2-7. Shoreline depth and substrate .................... . ................ 2-29 Figure 2-8. Lake Washington shoreline composition along a 14-mile reach of lakeshore on both sides of Port Quendall in September 1995.. .................. 2-34 Figure 3-1. Conceptual Gypsy subbasin drainage stream and buffer design ............ 3-8 Figure 4-1. Cross section through slurry containment wall .......................... 4-7 Figure 4-2. Typical cross section of conceptual wetland mitigation design . ............ 4-8 Figure 4-3. Cross section through containment wall for lake fill, Altematives 2 and 3. .. 4-19 19 June 1997 r-1171531mifigaterp2 Page iii A Port Quendall Drop Mitigation Analysis Memorandum LIST OF TABLES Page Table 1-1. Summary of Remediation Alternatives ............................... 1-3 Table 2-1. Nearshore Lake Washington total metals concentrations ................. 2-4 Table 2-2. Lake Washington Surface Water Quality near the Port Quendall Property .... 2-5 Table 2-3. Lake Washington water quality data collected near the May Creek mouth ... 2-6 Table 2-4. Port Quendall water quality results ................................. 2-11 Table 2-5. Results of metals screen for Lower Gypsy Subbasin Drainage at the culvert outlet to Lake Washington ....................................... 2-12 Table 2-6. Wetlands dredged or filled by the Port Quendall remediation actions....... 2-16 Table 2-7. Fish species in Lake Washington ......... ................ I ........ 2-21 Table 2-8. Benthic biota present its Lake Washington within or near the project site ... 2-26 Table 2-9. Lake Washington shoreline characteristics ........................... 2-30 Table 2-10. Comparison of shoreline conditions within the remediation area and the surrounding shoreline.......... .................................. 2-33 Table 2-11. Comparison of over -water pier coverage within the remediation area (1997) and the surrounding shoreline (1989)................................ 2-35 Table 3-1. Shoreline vegetation disturbance resulting from upland excavation and/or capping......................................................... 3-1 Table 3-2. Shoreline fish habitat characteristics after Remediation Alternative 1 ....... 3-4 Table 3-3. Shoreline fish habitat characteristics after Remediation Alternative 2 ...... 3-11 Table 3-4. Shoreline fish habitat characteristics after Remediation Alternative 3 ...... 3-13 Table 4-1. Summary of mitigation for impacts from each remediation alternative ...... 4-2 Table 4-2. Fish habitat -valuation of physical shoreline characteristics in remediation area.......................................................... 4-12 19 June 1997 ctHls3lnsffigaferpl Page iv Part Quendall Drat? Mitigation Analysis Memorandum I j LIST OF TABLES (Continued) Page i Table 4-3. Lake Washington shoreline fish habitat characteristics after remediation and mitigation ................................................. 4-13 i Table 4-4. Lake Washington shoreline fish habitat characteristics after remediation and mitigation.......... ........................................ 4-18 Table 4-5. Lake Washington shoreline fish habitat characteristics after remediation and mitigation .................................................. 4-22 19 June 1997 r:1212531mirfgafnrp2 Page v Port Quendall Draft Mitigation Analysis Memorandum PORT QULNDALL MITIGATION ANALYSIS MEMORANDUM 1.0 INTRODUCTION 1.1 - Objectives Mitigation analysis has been prepared for each of the remediation alternatives described in the Feasibility Study (FS) in detail and summarized below. The remediation areas include the Quendall Terminals (Quendall) and Baxter properties, as well as areas offshore of the Quendall and Barbee Mill properties. Since upland and shoreline remediation activities under all alternatives would be restricted to the Quendall and Baxter properties, this report does not include upland valuation of Barbee Mill, which is largely paved and an active mill site. The shoreline of Barbee Mill is included to give the context of the complete Port Quendall development site shoreline; however, no alterations to the Barbee Mill shoreline are proposed through remediation or mitigation activities. Resources with potential to be impacted by the site remediation plans are described in Section 2.0, and impacts to those resources for each remediation alternative are described in Section 3.0. A description of how the alternatives differ with regard to avoidance or minimization of impact, identification and selection of mitigation opportunities, and evaluation of mitigated function and values for each alternative are described in Section 4.0. Conceptual mitigation plans are provided for each remediation alternative action at the conclusion of Section 4.0. 1.2 Disclaimer Any work or work product addressed in this Mitigation Analysis Memorandum or cross-referenced herein and performed or to be performed by the Port Quendall Company (PQC) in the identified Port 19 June 1997 c_1111331m1[igate.g2 Page 1-1 Port Quendall Drafl Miligation Analysis Memorandum Quendall project area has been or will be undertaken only for purposes of determining the feasibility of the Port Quendall redevelopment project. This analysis may not be applicable for other developments with different plans. PQC, ReTec and Beak are submitting this document with the understanding that no independent liabilities shall be assumed by PQC under the Model Tox.ics Control Act (MTCA) or any comparable federal or state environmental laws should PQC elect not to complete'.purchase of the subject properties; nor shall the current owners of the Port Quendall project area be in any way obligated to undertake any mitigation approach or recommendation contained herein. 1.3 Reinediation Alternative Stinimary Descriptions Brief descriptions of the three remediation alternatives to the level of detail necessary for mitigation analysis are provided in Table 1-1 and shown in Figures 1-1 to 1-3. These descriptions include the "footprint" of each remediation alternative, as well as general characterizations of the impacts discussed in more detail in Section 3.0. 19 June 1997 C:1112531miNgale,rp2 Page 1-2 Port Quendall Draft Mitigation Analysis Memorandum Table 1-1. Summary ofRemediation Alternatives. 6-�=,A two . NOW, rna"tivel�;, 110 a i c A`Afteiriz;3. ,p pact rM i mac High Irnpact�' _ . ; Lake Fill 0.0 acres of fill Clean fill behind Confined disposal unit (includes sheet pile wall, fill groundwater behind containment of upland side, and clean containment wall. wall. material fill at 3:1 slope Lam: 0.5 acre of fill; Loss; 2.9 acres off Wending up to water surface. 0.4 acre < 4-It depth; 0.8 acre < 4-ft depth; on lake side) 0.1 acre of 4 to 6-ft 2.1 acres of 4 to 16-ft depth. depth. gaj�jl. Create 0.1 acre Gain: Create 0.3 acre along the fill perimeter, along the fill perimeter. Net to et loss-. 0.3 acre < 4-ft; 0.5 acre < 4-ft; 0.2 acre > 4-ft. 2.4 acres > 4-ft. Shoreline Disturbance 0% of Barbee, 0% of Barbee, 0% of Barbee, (includes loss of vegetation, 100% of Quendall, & 100% of Quendall, & 100% of Quendall, & if any; removal and/or fill of 50% of Baxter, which 50% of Baxter, which 50% of Baxter, which upland soils; and sheet pile includes 100% includes 100% includes 100% or slairry wall approximately elimination of Wetlands elimination of Wetlands elimination of Wetlands 20-50jeet upland of Ot1W A and B. A and B. A and B. from Quendall-Barbee property line north to utility ROW) Dredge offshore PAH Two "T-Dock" areas Two "T-Dock" areas Two "T-Dock" areas (refill to original elevations and Wetland E (a.k.a. and Wetland E (A.k.a. and Wetland E (a.k,a. with clean material) 'Baxter Cove") "Baxter Cove") "Baxter Cove") Dredge offshore areas with > Areas offshore of Areas offshore of Areas offshore of 50% wood chips (with no re- Barbee and south Barbee and south Barbee and south fall; original elevations Quendall Quendall Quendall assumed restored by chip removal). Upland soil excavation and 100% fill of Wetlands 100% fill of Wetlands C 100% fill of Wetlands C capping C and D and D and D Gypsy subbasin culvert Gypsy subbasin open Gypsy subbasin open Gypsy subbasin open replacement (replace with channel portion channel portion . channel portion larger diameter under clean relocated to shoreline on relocated to shoreline on relocated to shoreline on upland cap after excavation) Baxter Baxter Baxter 19 lone 1997 e:12225JWutgaIe.rp7 Page 1-3 MILL t a 0 a n PORT OUENDALLREMEDIATION PROI(CT nGuPJ l.i REMEDGUIONAITFRNATNf i ((OWIMPAM SWK[RiFR XF:til[c / a 0. PAN ABODE L 9 0 E N D Dredge offshore areas with >50% wood chtps (no refill, original elevations assumed restored by chip removoll FAH dredge areas (to be returned to existing grade wish clean gravels aher dredging( Upland soil excavated and copped. Areas of extensive sail excavation, treatment and capping. (Creation of miligotlon elements to these areas will require corelut Integration with uplands Femedy, however, millgatlon wolerward of wall is feasible) Upland sell grading and copping. Areas of gtoding, capping of remedimion staging, (creotlon of miligotfon elemems in these areas Es feasible) Wetlands -rk-t s Witt b-e-. 11xIT PORI QUINDALI RIMEDIATIA PROTECT FQtF REMEDL400HA(TERNATM2 (MEDIOM I iPACO SOl aIilflrioRW A// L E G E N D Late fill: Seep cantoinmerss area (05 acres}, This area filled with {odor Pint secilmenis behind a tansalnroent wall, with a V slope eitendfng alp to she surface on she Walser side, Dredge offshore areas with >50%wood chips (no refilli original elerollons assumed retsored by chip removal) /el FAH dredge areas [Io be resumed Fa existing grade with clean gravels after dredging] kkmi,j;,; ,. Upland sail excovakd and capped. Areas of extensive sail u moiioa, tmolmeas and !'��'.''! mppi g. (Creation of mlligation elements in these areas will require careful Imagrasioa with uplands rernedr; however, mitigation wolerword of wall is feasible) Upland soil grading and capping. Areas of grading, copping of rtmediation sloging, am {crealionof mriigalioo elements in These areas is leosiblej Wetlands ;FT �ak 1_J =] PAN ABODE &a ILL ❑ L E 0 E H D Lake fill: Confined disposal unit has PAN impamed sedimenh (7.9 acres) witb a 3:1 slope exsending up 10 Iha surface on I he rater side Dredge offshore areas whh >5d% wood chips (no refill; original elevolians assumed restored by chip removal) PATS dredge areas (Io be rolurned to exlsli g grade with dean gravels oher dredging) O Upland soil eiaavafed and capped. Arens of exleraive soil excavalian, Imminent and capping. (Creation of mitigation elements in these areas will require careful integration with uplon& temedr however, mlligolion walerword of wall is feasible) PORT OUENDATI REMEDIATION PROJECT Upland soil grading and copping. Areas of grading, copping of remediolion stoging, Fla[ 13 (creation of mil' onion elements in Ihasa areas Is feasible) REMENTTONAITERNATIVE3 RGH IMPAM SOUREf 1E1ERiNCL• RITH Wellands aROL72T 3JUNEW Port Quendall Drat? Mitigation Analysis Memorandrrnt 2.0 DESCRIPTION OF AFFECTED RESOURCES 2.1 Water Quality Lake Washington is the largest lake in King County with a drainage area of 472 square miles and an area of 21,500 acres. The lake has a volume of 2.35 million acre-feet, a mean depth of 108 feet, and a maximum depth of 214 feet. The Lake Washington watershed is urban, with approximately 63 percent of its area developed (Metro 1989). The main inflows to the lake are the Cedar River in the south end (57%) and the Sammamish River in the north end (27%). The Cedar River contributes 25 percent and the Sammamish River contributes 41 percent of the phosphorus load to the lake, respectively. The lake outlet is the ship canal, which flows through Portage Bay and Lake Union to Puget Sound near Shilshole. Metro has established numerous water quality monitoring stations throughout Lake Washington (Figure 2-1). Most of the historic water quality data available for Lake Washington are from 5 nearshore stations established in Juanita Bay, Yarrow Bay, . Newport, Meydenbauer Bay and Kenmore, which are all north of the remediation site. However, additional nearshore and offshore stations were added to the monitoring effort beginning in 1992, which included three near the Port Quendall remediation site. These three lake stations are located at the mouth of May Creek (stations 0839 [shallow] and 0840 [deep]), and near Renton (station 0831). Lake Washington is listed as water quality limited for sediment under the 1972 Clean Water Act (Section 303(d) Segment No. 08-9350). Six sediment bioassay studies are cited as the basis for the listing. Three of the six bioassays were conducted on sediment collected near the Port Quendall site (Norton 1991; Norton 1992; Bennett and Cubbage 1992). Lake Washington (Waterbody Segment Number WA-08-9350) is listed as impaired for wildlife habitat as a result of industrial point source pollution. 19 June 1997 r:1213SAndrigatrrp2 Page 2-1 p 0804 i � a ,�. ; a, SAMMAMISH } RYVER IM,x f � �� 0a26 } LAKE k s 5512 IUNIflN 053b M A522 LAKE Zv . WASHINGTON *5Kt 0834 S �r �t SEATTLE�� t x � . 0832 MIN } PORT QUENDALL ° r PROJECT SITE x MAY CREEK 0831 � PORT QUINDAU REMMATION PROJECT 0829 CEDAR RIMER FIGURE 2-1 i LEGEND METRO WATER QUA [ITY SAMPI NG STATIONS 1N IAXE WASHNGTON 0814 HISTORIC WATER QUALITY STATIONS I PROJECT NO.: 22223 19 tmy 1997 r'yak ' SHALLOW STATION 1 h�5 2223.2-1_CD9W CHECKED. T15 DEEP STATION a. b/w g -X I --�, -P, no- Port Quendall Draft Mitigation Analysis Meinorandump South Lake Washington Beak Consultants Incorporated collected one on -site shoreline water sample on 21 March 1997 from Lake Washington approximately 200 feet south of the lower Gypsy Subbasin Drainage outfall. This sample was analyzed for metals (e.g., cadmium, copper, lead, and zinc) and hardness (Table 2-1). Cadmium and zinc exceeded the State standards for acute toxicity, and lead exceeded the chronic toxicity standard. The exceedences were based on State standards (WAC 173-201 A) for metals at the ambient hardness of 32 mg CaCO3/1. Metro has monitored two Lake Washington stations near the mouth of May Creek and an offshore station near Kennydale Park in Renton (Table 2-2). The sampling frequency varied, but was from approximately 1992 to the present, with samples collected bimonthly. Parameters monitored were temperature, D.O., pH, conductivity, transparency, turbidity, alkalinity, nitrate+nitrite-nitrogen, ammonia nitrogen, total nitrogen, orthophosphate, total phosphate, chlorophyll -a, phaeophytin, fecal coliform, and enterococcus. The lake water quality near the Port Quendall Development Site can be described as moderately good for a mesotrophic urban lake. Water quality for the whole lake is rated by Metro as good, except for algal blooms in periods of warm weather. Average transparency for the south lake stations was 3.8 m. Fecal coliforms were high at the May Creek nearshore station (average of 128 MPN), as was chlorophyll -a (9.6 mg/m3 in 1996). Nutrients were low at the Keruiydale Park and May Creek lake stations, with the average nitrate + nitrate nitrogen value less than 0.25 mg/I and the average orthophosphate less than 0.010 mg/l. Transparency, total phosphorus, and chlorophyll -a trends for METRO station 0839 during water years 1992 through 1994 indicate decreased transparency, slightly increased phosphorus, and slightly decreased chlorophyll a (Table 2-3). 19 June 1997 e:1222531mf1iga(e_rp2 Page 2-3 Port Quendall Draft Mitigation Analysis Memorandum Table 2-1. Nearshore Lake Washington total metals concentrations for a water sample collected south of the Gypsy subbasin culvert outfall on the Baxter parcel. ices t mg/11 Lake,Clas r tr>la (WACE17 rag -Stand rd e(? ' .� M'r Cadmium: 0.0010 acute 0.0009 -NO chronic 0.0004 NO Copper: 0.002 acute 0.0052 YES chronic 0.0038 YES Lead: 0.001 acute 0.0132 YES chronic 0.0005 NO Zinc: 0.054 acute 0.0397 NO chronic 0.0360 NO Water sample collected from Baxter parcel shoreline by Beak Consultants on 21 March 1997. Metals standards shown for hardness of 32 mg/l as CaCO3 in the sample. 19 June 1997 c. U22S31mUipafe. rp2 Page 2-4 Table 2-2 Lake Washington Surface Water Quality. near the Port Quendall Property Water Year Water.Temp D. O.** pH ** Cond.** Transparency" Turbidity ` Alk (mg/l} . Estero. /Station " m /1) umhos/cm2 Secchi m T as CaCO3 . s MPN:. 992-1996 / 0831 13.68 10.43 7.86 96 4.2 1.2 36.4 10 992-1996 / 083 15.55 11.11 7.83 97 4.4 1.3 36.0 54 1995 / 0840 14.24 11.34 8.29 97 3.5 0.9 38.0 1 1996 10840 13.72 10,23 7.79 97 3.2 1.4 36.0 10 1997* / 0940 12.44 9.40 7.54 94 3.7 0.6 38.1 19 Water Year.: NOX :' Ammoaia - Total Nitrate - N Ortho P ' Total' P Chlorophyll -a Phaeophytin Fecal Coliform !Station (m /l) Nitroeen mall (mall) (m /l) (m2/1) ms/m3 I mg m3 MPN 1100nil 992-1996 10831 0.157 0.022 I 0.296 0.009 0.022 4.4 1.5 25 992-1996 / 0839 0.117 0.029 0.31 0,008 0.017 4.2 3.4 128 1995 / 0840 0.190 nm 0.32 0.006 0.020 9.6 1.0 2 1996/0840 0.181 0.031 0.324 0.007 0.020 TIM nm 25 1997* / 0840 0.226 0,021 0,289 0.008 0.017 nm ntn 52 Notes: Lake Washington water quality data collected near Renton from 1992 to 1996 (Metro station 0831) Lake Washington water quality data collected from 1992 to 1995 offshore of May Creek mouth (Source Metro station 0839). Lake Washington water quality data collected near May Creek mouth (Metro station 0840 - Deep Lake Station). Monthly average of water quality data collected at a depth of 1 meter, nm - not monitored * 1997 data includes only October, November and December. ** Field measurement 06/19/97 solkwawq. wk4 Port Quendall Draft Mitigation Analysts Memorandum i Table 2-3. Lake Washington water quality data collected near the May Creek mouth. �.. x �,r,}. f 5ecch aDisc 4 ter. �(meer) �€ _.y. �1 hhat ( ) Chloiophyil= t� 1 I May 92 5.0 nm 21.0 18 May 92 3.4 0.011 1.5 26 May 92 4.6 nm nm 01 June 92 6.0 0.006 1.6 15 June 92 5.7 0.001 nm 22 June 92 5.8 0,023 nm 06 July 92 5.5 0.0009 2.1 20 July 92 4.4 0.010 nm 03 Aug 92 4.7 0.010 0.9 10 Aug 92 4.4 0.008 nm 17 Aug 92 4.1 0.017 nm 24 Aug 92 4.5 0.028 nm 31 Aug 92 4.3 0.020 nm 08 Sep 92 3.6 0,029 2.9 Average: 4.7 0.014 5.0 nm = not monitored Source: Metro Station 0839 (shallow) 19 June 1997 c:1222SjUnitrgiae.rp2 Page 2-6 I Port Quendall Draft Mitiga[ion Analysis Mentorand,trn i i { Table 2-3. Lake Washington water duality data collected near the May Creek mouth. (Continued). 'DATA ' Se ch>I Disc : ('I ransparency) Tota"�[ Pho phR e s I �j Chlo o hyll a (mglar3)'` 1 05 Oct 92 5.0 0.014 2,5 20 Oct 92 4.2 0.015 nm 02 Nov 92 6.5 0.017 1.8 17 Nov 92 4.6 0.022 2.3 01 Dee 92 4.5 0.027 2.8 04 Jan 93 6.0 0.035 3.2 01 Feb 93 3.3 0,012 2.7 01 Mar 93 3.3 0.025 7.6 16 Mar 93 2.4 0.021 0.7 05 Apr 93 2.1 0.024 21.0 19 Apr 93 2.1 0.019 I l.0 03 May 93 3.0 0.009 4.0 25 May 93 3.3 0.036 4.5 07 Jun 93 5.0 1 0.014 2.0 06 Jul 93 4.0 0.019 0.5 02 Aug 93 3.0 0.059 0.1 07 Sep 93 4.2 0.009 0.4 Average: 3.9 0.022 4.2 Source: Metro Station 0839 (shallow) 19 June 1997 e_1222131midgalerp2 Page 2-7 Port Quendall Draft Mitigation Analysis Memorandum Table 2-3. Lake Washington water quality data collected near the May Creek mouth. (Continued). ' SecchiDisc �a#aEPosphakeIF;; fl) ��x'rr t V4 �f t a 04 Oct 93 To 0.009 0.4 01 Nov 93 5.0 0.011 2.4 08 Dec 93 5.5 0.018 0.5 05 Jan 94 5.0 0.081 0.4 15 Feb 94 3.8 0.011 4.1 07 Mar 94 3.2 0.023 4.5 21 Mar 94 2.5 0.020 6.1 04 Apr 94 2.8 0.045 18.0 18 Apr 94 3.0 0,012 7.7 02 May 94 3.8 0.020 6.3 23 May 94 2.7 0.017 6.9 06 Jun 94 3.5 0.013 7.2 05 Jul 94 4.0 0.018 3.6 04 Aug 94 5.0 0.031 2.0 06 Sep 94 4.5 0.017 2.0 Average: 4.1 0.023 4.8 Source: Metro Station 0839 (shallow) 19 June 1997 r:12225JlmirrgaIrrp2 Page 2-8 Port Quendall Draft Mitigation Analysis Memorandum Table 2-3. Lake Washington water quality data collected near the May Creek mouth. (Continued). eccht Disc { s (Tran�rency)v .�x�"iC"ie-s aial Phdsp A e (ingJi� Chlorophyll�a (mghn3). te"r)' 03 Oct 94 6.0 0.011 2.5 02 Nov 94 5.0 0.027 2.4 05 Dec 95 4.0 0.02$ 2.3 23 Jan 95 5.5 0.027 5.0 Average: 4.8 0.028 3.7 Source: Metro Station 0839 (shallow) 19 lune�l997 _ - - - -- — — -- -- - -- c,U225JIm igara.rp2 Page 2-9 Port Quendall Draft Mitigation Analysis Memorandum Gvosv Subbasin Drainage No historic water quality data were available for Lower Gypsy Subbasin Drainage. The Lower Gypsy subbasin flows from the east side of 1-405 through an approximately 125-foot open channel before entering a culvert in the northern area of the project site that discharges directly to Lake Washington. Lower Gypsy subbasin water discharges via tightline directly to Lake Washington and is thus classified as Class A (extraordinary) by WAC 173-201A. This drainage is distinct from Gypsy Creek, which joins May Creek at RM 1.15. Baseline water quality monitoring of the Lower Gypsy subbasin began on 28 March 1997 (Table 2-4). Monitoring will include two more wet periods in Spring of 1997 and a baseflow period during September 1997. Preliminary results were consistent with an urban stream and show some influence of upstream wetlands. Waters were neutral, cool, with low dissolved oxygen, high conductivity, and high total dissolved solids. Oil and grease were below detection, fecal coliform were moderate (41 CFU/100 nil) and hardness was moderate. Nutrients were moderately elevated: nitrate and nitrite oxygen was 1.0 nng/l and total phosphorus was .038 mg/1. All metals met the chronic toxicity standard (WAC 173-201 A) adjusted for the ambient hardness (Table 2-5); however, while cadmium, lead, mercury, and silver were all below detection, the detection levels for these metals were above their respective standard. Based on the limited water quality data (one sampling event), dissolved oxygen was below the Class AA standard (>9.5 mg/1). Turbidity may not meet the standard, but compliance was not determined because of lack of baseline data. It is likely that temperature would not meet the standard (<16°C) during the summer months due to the low elevation and the wetland component of the stream system. During some site visits, a strong sewer odor has been noticed where Gypsy subbasin enters the site from the east; however, this odor was not apparent during the single monitoring event reported here. Origin of this odor is not obvious. 19 June 1997 CA222511mrrigare.rp2 Page 2-10 Port Quendall Draft Mitigation Analysis Memorandum Table 2-4. Port Quendall water quality results. Three wet season and one baseflow - Spring and Summer 1997. Lower Gypsy Subbasin Drainage outfall to Lake Washington. to666 -"�k,: kit6 , A p ratuOs V Cm O(Add I &'Ciifis6TPH:., ' GCSM (3128/97) 10.21 9.85 J7.15 8,00/71-8 180 T <1 Station: r1PV -A Itr*AMm 0 1� 101at'r 0 GCSM 0.028 1.0 0.5 0,038 0.025 4 siftii,n.�L ["Y;-T(14; �ilnes-s Mill) Tur, rfl� g IP4 GCSM 110. 5 6,3 <0.02 <0-002 0.06 74 .0.02 (dissolved) <0.002 (dissolved)] —0() 10 5(dissolved)l Monitoring Date: 28 March 1997 24-hour rainfall recorded at Sea-Tac was 0.10" on 27?vlarch 1997. * See Table 2-5 for a complete listing of the metals screening analysis. 19 June 1997 rA222531ndfigarr rp2 Page 2-11 Port Qatendall Draft Mitigation Analysis Memorandum Table 2-5. Results of metals screen for Lower Gypsy Subbasin Drainage at the culvert outlet to Lake Washington. Parameter 3k 1 ; r v y ? { rt 28I43srch Result =4 Y t tDeReclinn Limit�� ,,, Aluminum 0.26 0.01 Antimony <0.02 0.02 Arsenic <0.03 0.03 Boron <0.1 0.1 Barium 0.015 0.003 Beryllium <0.005 0.005 Calcium 18.0 0.1 Cadmium <0.002 0.002 Cobalt <0.003 0.003 Chromium <0.006 0.006 Copper <0.002 0.002 ron 1.6 0.01 Mercury <0.01 0.01 Potassium 2,2 1.0 Lithium <0.02 0.02 Magnesium 7,2 0.1 Manganese 0-320 0.002 Molybdenum <T01 0.01 Sodium 8.9 0.1 Nickel <0.01 0.01 Phosphorus 0.08 0.05 Lead <0.02 0.02 Sulfur 3.3 0.1 Selenium <0.03 0.03 Silicon 1.0 0.10 Silver <0.01 0.01 Tin <0.02 0.02 Strontium 0.120 0.003 Titanium <0.01 0.0i Thallium <0.03 0.03 Vanadium <0.002 0.002 Yttrium <0.001 0.001 Zinc 0.060 0.002 Samples collected on 29 March 1997, Lower Gypsy Creek subbasin outfall at Lake Washington. Note: Total metals. Alt values are in mg/l. EPA Method 200.7. Italics indicate results which exceed or may exceed the WAC 173- 201A surface water standard (chronic); the ambiguity occurs when the standard is lower than the detection limit and the result is below detection. Bold italics indicate a result which may exceed the acute standard (silver). 19 June 1997 c:1122331n,&igaterp2 Page 2-12 Port Quendall Draft Mitigation Analysis Menaorandtun 2.2 Plants and Animals The Port QuendalI and Baxter parcels are sparsely vegetated. Five wetland areas were delineated within the Quendall/Baxter remediation area (David Evans and Associates 1997 Figure 2-2). The Port Quendall parcel is currently an active log yard; vegetation on the site is primarily limited to the shoreline (Figure 2-3, Table 2-6). Two of the wetlands (Wetlands A and B) are found along the Quendall shoreline. Wetland A is a palustrine forested wetland dominated by immature red alder (Alnus rubra) and Himalayan blackberry (Rubus discolor), with a sparse herbaceous layer of reed canarygrass (Phalaris arundinacea), buttercup (Ranunculus repens) and yellow flag iris (Iris pseudacorus). Wetland B is a palustrine forested wetland comprised of red alder with a hardback (Spiraea douglasii) and Pacific willow (Salix lasiandra) shrub layer. Hydrology in Wetlands A and B is controlled by the lake level. Only minor surface discharge enters these areas. Vegetation and embedded logs help stabilize the shoreline. These wetlands provide little flood control, base flow support or water quality improvement, because they lie along the shoreline and receive little surface discharge. A third wetland (Wetland C) located on the Quendall parcel is a remnant of an old industrial lagoon which currently supports a permanent open water component, emergent vegetation dominated by cattails (Typha latifolia) and a black cottonwood (Populus balsamifera) sapling shrub layer. Wetland C detains some drainage from the adjacent log yards and therefore provides some water quality function by diverting this runoff from the lake. However, no outlet was observed and the area appears to be isolated from ground water, therefore, no base flow support is provided by this wetland. The remaining vegetated shoreline along the Quendall parcel is dominated by red alder, willow and Himalayan blackberry. Industrial activities on the Baxter parcel ended in the early 1980s; a portion of the site is currently used to store bark mulch. The compacted fill soils on the Baxter parcel support sparse stands of non- native grasses and patches of sapling- and seedling -size black cottonwood and soft rush 19 June 1997 c.1222s3lmiligarGrpl Page 2-13 NOTE: AA ha5ltal, Welland, and project lealate iacalions and ® BMWMBERRY gaonlitles are appraxlmate_ SHRUBS TREES WEIUHII LA MILFOIL B PORT 9UENML `WMEE ❑/ Z> t.D N /P�MOME Port Quendal! Draft Mitigation Analysis A9emorandrim Table 2-6. Wetlands dredged or filled by the Port Quendall remediation actions. Area «� Physical s 4 t;Brological E _ ;. �'Vetland',; I A`txei;AR4,; Y. Characteristics Sn ort` A 0.20 Welland along Lake Washington PFO - immature red alder with a I Iimalayan shoreline, minor surface discharge from blackberry understory and a sparse project site; some shoreline protection herbaceous cover of cattail, reed canarygrass, provided by vegetation and logs buttercup and flag iris; habitat value is embedded nearshore; little flood control, moderate due to adjacency to the lake; base flow support or water quality provides potential habitat for amphibians, improvement is provided. passerine birds and limited waterfowl nesting - observed wildlife use includes Canada goose, beaver, several species of passerine birds. B 0.37 Wetland along Lake Washington PFO - red alder with a hardback and Pacific shoreline, minor surface discharge from willow shrub layer; habitat value is moderate project site; some shoreline protection due: to adjacency to the lake; provides provided by vegetation and logs potential habitat for amphibians, passerine embedded nearshore; little flood birds and limited waterfowl nesting; control, base flow support or water observed wildlife use includes Canada goose, quality improvement is provided. beaver, several species of passerine birds. C 0.11 Excavation in fill material; detains PSWEIvVPOW - black cottonwood saplings, drainage from log yards; no outlet was cattails and soft rush; perennial open water; observed and the area appears to be low habitat value due to low vegetative isolated from ground water, therefore diversity and isolated nature of area; no base flow support is provided by observed wildlife use includes Canada goose, this Nvedand; water quality mallards, and green heron. improvement provided by detention of log yard runoff. D 0A8 Old industrial settling pond isolated PSS - small wctland within former industrial from Lake Washington; little flood area dominated by cattail, Pacific willow and control or base flow support is red -osier dogwood; overall habitat value is provided; no water quality low; observed wildlife use includes red - improvements provided. winged blackbird, snipe. E 0.23 Cove created by fill along the lake PEM/POW(PSS - cattail, Himalayan (Baxter Cove) shoreline; some shoreline protection blackberry, red -osier dogwood and red alder provided by vegetation and logs sapling; emergent vegetation established after embedded nearshore; flood control, 1990; habitat value is moderate due to base flow support and water quality adjacency to the lake; provides potential improvement are limited due to the habitat for amphibians, passerine birds and small area that drains into the cove. water fowl; observed wildlife use includes turtles (painted and sliders); beaver, red -wing blackbird, mallards. 30 April 1997 19 June 1997 c:t222S3tmWXartrp2 Page 2-16 Port Quendall Draft Mitigation Analysis Memorandum (Juncus effusus). Baxter Cove (Wetland E) is found along the southern Baxter shoreline and appears to have been created by shoreline fill or fill and dredge activities. Baxter Cove supports i an open water component, cattails and a shrub layer comprised of Himalayan blackberry, red alder saplings and red -osier dogwood (Corpus stolonifera). The second wetland area (Wetland D) on i Baxter is an old industrial pond isolated from Lake Washington that is dominated by cattail, Pacific willow and red -osier dogwood. Historically, flows from Wetland D discharged into Baxter Cove. However, the outfall section of the pipe was collapsed several years ago to stop the contaminated discharge in Baxter Cove. Currently, the flood water control, base flow support and water quality functions provided by Baxter Cove and Wetland D are limited due to the small area that drains each wetland area. A narrow band of vegetation, approximately 25 feet wide, along the remaining Baxter shoreline is comprised of Scotch broom (Cytisus seoparius) and Himalayan blackberry. A short open channel section of the Gypsy Stibbasin Drainage is also located on the Baxter parcel. Sapling red alder and willow are present on the steep banks of the channel. This drainage is regulated as a water of the US by the US Army Corps of Engineers. However, no habitat value is provided by this vegetation. In general, the habitat value of the remediation area is low due to the disturbed nature of the former and active industrial areas which support limited vegetation. Oily sheens were observed on the surface of the open water wetland areas and areas along the lake shoreline_ The shoreline areas provide the highest habitat value in the remediation project area, but the habitat value of these areas are limited due to the dominance of non-native invasive plant species, lack of vegetative diversity and structure, and lack of special habitat features such as snags and woody debris landward of the shoreline. 19 June 1997 C.1111M31mi6galc.ry2 Page 2-17 Port QuendalI Draft Mitigation analysis Memorandum Most of the wildlife use observed on the site occurs along the Quendall and southern Baxter shoreline. Canada geese (Branta canadensis) were observed in both the vegetated and hardscape shoreline areas. The geese were observed nesting along the vegetated shoreline and in the osprey nest located on the Quendall Cable Station nesting platform. Puget Sound Energy (formerly Puget Sound Power & Light) moved an osprey nest from a retired distribution pole on the Baxter site to a new nest pole platform erected on the south side of the cable station in 1993. Puget Sound Energy also placed a perch on top of the first transmission pole leading away from the station to provide a safe place for the birds to perch. The osprey (.l'andion haliaetus) have successfully nested on the platform since the transfer of the nest in 1993 until this year, when the osprey built a new nest at the top of the wood chip elevator located on the Barbee Mill site. The osprey are present in the area from mid -March through August. Osprey have been observed hunting small mammals (likely mice) on the north Baxter site as well as fishing the lake. Canada geese and bald eagles (Haliaeetus leucophalus) have occasionally been observed perching on the nest platform during the winter months. It is assumed the bald eagles used the perch site to forage for fish and waterfowl along the lake shoreline. The closest known bald eagle nest site is located approximately 0.75 mile west of the remediation area (WDFW May 1997 PHS database). Beaver (Castor canadensis) have been observed in the wetland habitat along the Iake shoreline. Waterfowl, such as ducks and cormorants, frequent the shoreline waters and perch on the exposed pilings. Pond sliders (Pseudemys scripta) are present in Baxter Cove and have been observed on floating logs off of the southern Baxter and northern Quendall shoreline. Ducks also use the open water habitat of Baxter Cove. Red -winged blackbirds (Agelaius phoenicetts) were observed using cattail habitat along the shoreline, including Baxter Cove, and isolated patches of cattails away from the shoreline (Wetland D). Snipe (Capella gallinago) were observed in the Wetland D area and in the cottonwood sapling -dominated areas on the Baxter parcel. Other species of passerine birds and amphibians could be supported by the shoreline wetlands and the narrow red alder -dominated upland shoreline area. 19 June 1997 e:1222S31midgotrrp2 Page 2-18 Port Quendall Draft Mitigation Analysis Meinoranduln 2.3 Fisheries 2.3.1. Introduction This section describes existing fish habitat conditions within the area impacted by remediation activities, and provides an assessment of the various components that make up this habitat. A description of known fish use of the habitat is also provided. The remediation activities are being implemented with the primary intent of enhancing sediment and water quality in Lake Washington. This will benefit all species rearing and migrating along the project shoreline. Remediation alternative actions with the potential of permanently impacting fish include various amounts of filling of nearshore habitat. Temporary impacts may include replacing the Gypsy subbasin culvert, reconfiguration of the shoreline, dredging of contaminated sediments, filling of the dredged areas with clean soils, and removing wood chips from the lake (Table 1-1). These actions will impact primarily the shoreline and may affect nearshore habitat to about 900 feet from shore. Existing conditions for each of these areas is described in the following text. 2.3.2 Lake Washington Biology ela is Specio Lake Washington supports a variety of anadromous salmonids, including chinook (Oncorhynchus tshauytscha), coho (O. kisutch), and sockeye salmon (O. nerka), and steelhead (O. mykiss) and cutthroat trout (O. clarki). Runs of non-anadromous kokanee (O. nerka) salmon are also present (King County 1993). Lake Washington contains a wide variety of non-salmonid species, some of which are considered "warm water" species. These include both native and non-native species such as speckled dace (Rhinichthys osculus), three -spine stickleback (Gasterosteus aculeatus), northern 19 June 1997 c.122253Wfigaterp2 Page 2-19 Port QuQndall Draft Mitigation Analysis Memorandum squawfish (Ptychocheilus oregonensis), yellow perch (Perca flavescens), black crappie (Pomoxis nigromaculatus), largemouth bass (Microplerus salmoides), smallmouth bass (Micropterus dolomieui), mountain whitefish (Prosopium williamsoni), largescale sucker (Catostomus macrocheilus), longfin smelt (Spirinchus thaleichthys), and prickly sculpin (Cotuts asper) among other species (Pfeifer and Weinheimer 1992, King County 1993,.Wydoski and Whitney 1979). A more complete list of fish species potentially found near the project is provided in Table 2-7. t i Of particular importance to the project is the population of sockeye salmon juveniles which rear in Lake Washington. These fish may utilize the shoreline and offshore habitat along the project for rearing. The majority of sockeye outmigrate from the Cedar River, although a smaller number may be the result of beach spawners. The Cedar River sockeye is a non-native species originating predominately from Baker River stock and introduced in 1935 (WDFW et al. 1994). The stock is currently believed to be depressed based on a long-term negative escapement trend (WDFW et al. 1994). Sockeye are. not known to have spawned historically along the Port Quendall Project site (Muckleshoot Indian Tribe 1997). Areas of suitable substrate were looked for during diver and video surveys for this project. It was assumed that any area with small to medium sized gravels and evidence of upwelling may be used; however, no suitable habitat was found nor was there any evidence of redds. Early speculation regarding the existence of a small upwelling site in about 30 feet of water off the mouth of May Creek was not supportable. During a follow up interview with the diver responsible for the survey, he indicated that the disturbance noted on the video (Figure 2-4) was probably caused by a fleeing fish rather than upwelling water (Maxwell, pers. comm., 1997). Substrates in the vicinity consist primarily of fine silts and are too small to be usable for spawning. Upwellings may exist in the property vicinity that were not observed by divers; however, geohydrology studies and modeling do not suggest concentrated points of upwelling are expected to occur. 19 June 1997 { c.1112531midgafr.g2 Page 2-20 Port Qrrendall Draft Mitigation Analysis Memorandum Table 2-7. Fish species in Lake Washington. "ufil . ante � S tit' .. sine ��oriii�u"-°'a"trl`e Petromyzontidae Western brook lamprey Lamperra richardsoni Lampreys Pacific lamprey Enlosphenus tridenratus River Lamprey Lampeira ayresi Acipenseridae White sturgeon Acipenser iransmonlanus Sturgeons Clupeidne American shad Aloso sapidissima Herrings Salmonidne Mountain whitefish Prosopium williamsoni Trouts Cutthroat trout Oncorhynchus clarki Rainbow trout (steelhead) _ Oncorhynchus mykiss Brook trout Salvelinus fontinalis Lake trout Salvelinus namaycush Coho salmon Oncorhynchus kisuich Chinook salmon Oncorhynchus rshaivylscha Chum salmon Oncorhynchus keia Pink salmon Oncorhynchus gorbrrscha Sockeye salmon (kokanee) Oncorhynchus nerka Osmeridae Longffi smelt Spirinchus ehaleichlhys Smelts Cyprinidae Carp Cyprinus carpio Minnows Peamouth Mylocheilus caurinus Northern squawfish Prychoceilus oregonensis Speckled dace Rhinichthys oscrrlus Redside shiner Richardsoidus balleaius Tench Tinca Unca Catostomidae Largescale sucker Catostonnrs neacracheilus Suckers Ictaluridae Brown bullhead kraherus nebulosus Catfishes Channel catfish k1ah4rus punclarus Gasterosteidae Threespine stickleback Gasterosleus aculeatus Stickleback Cenlrarchidne Smailmouth bass Micropierus dolondeui Sunfishes Largemouth bass Microplerus sninroides Black crappie Poxomis nigromaciolarus Pereidne Yellow perch Perca flavescens Perches Cottidae Coastrange sculpin Coitus aleertieus Sculpins Shorthead sculpin Comes confuses Torrent sculpin Coitus rhotheus Prickly sculpin Collus asper Riffle sculpin Coitus gulosus Pacific staghorn sculpin Le iocollus amalus Source: Shepard and Hoeman 1979. 19 June 1997 c_1121531m11igaa.rp2 Page 2-21 A. ;V Port Quendall Draft Mitigation Analysis Mernoranduni Naturally spawned fry begin leaving the Cedar River each year starting in late December. Millions more hatchery fry are released into the river starting in March. The fry migrate downstream to Lake Washington where they may spend from one to two years before emigrating to the sea. Recent studies in southern Lake Washington found the majority of sockeye fry migrate into deep water soon after reaching the lake and head north (Burgner 1991, UW 1996). A few fry were found in the nearshore environment for up to one month after emerging. By late summer, sockeye densities are highest at the north end of the lake (Burgner 1991). Predation of sockeye fry in Lake Washington is believed to be a major cause of low recruitment (University of Washington 1996). A considerable amount of research is currently being undertaken by the Muckleshoot Tribe, U.S. Fish and Wildlife Service (USFWS), University of Washington (UW), Washington Department of Fish and Wildlife (WDFW) and King County to better understand the early life history of sockeye in Lake Washington and the various factors influencing predation. Currently nor -them squawfish and cutthroat trout are believed to be the major predators of fry (UW 1996). Estimates of sockeye consumption by squawfish in Lake Washington range between 3,000,000 and 11,000,000 fry per year (UW 1996). Smallmouth and largemouth bass, prickly sculpin, yellow perch, rainbow trout and coho salmon also consume sockeye juveniles but in much fewer numbers. Although bass are commonly believed to be major sockeye predators, recent evidence indicates this is not entirely true (UW 1996). Life history studies of the two bass species and sockeye in Lake Washington show few opportunities for the three species to interact. Gut analysis confirmed the studies (UW 1996). Less than approximately 10 percent of the diet of smallmouth bass is salmon, and only for a few months each spring. Most sockeye consumed by largemouth bass are taken in the ship canal where they are concentrated during the outmigration period. Total bass consumption of sockeye fry is estimated at less than 100,000 fish per year (UW 1996). 19 June 1997 c.U22531mi1igafarp2 Page 2-23 Port Quendal! Draft Mitigation Analysis Memorandum Ten beach seining surveys at Kennydale Park, approximately 0.7 miles south of the remediation site, were conducted by the US Army Corps of Engineers and the Muckleshoot Indian Tribe between February and June, 1994 (Martz et al. 1996; Muckleshoot 1997). One survey was completed during the day and one survey at night each month. Relatively high numbers of sockeye fry, chinook fry, coho fry, and yellow perch were captured (Figure 2-5). Lesser numbers of sockeye presmolts, smallrnouth bass, and squawfish were caught. Most sockeye were observed in May during the daytime surveys. A high number of yellow perch were also captured during the same survey. Fewer sockeye fry were captured in June but a higher number of chinook were netted. Again, an abundant yellow perch population was also netted. The coho population peaked in April. Benthic Specie Crayfish (Pacifasticus sp.) and freshwater shrimp (Ostracods and Mysids) are relatively abundant benthic biota in the vicinity of the project. Numerous individuals were observed in diver and video surveys within the outer harbor line. Most crayfish were associated with larger pieces of wood where many were noted protecting the entrance to dens under logs. Freshwater clams (Pelecypods) were also noted in several places on the lake bed. Other benthic species found in Lake Washington, within and around the remediation bounds are listed in Table 2-9. 2.3.3 Lake Washington Shoreline Survey Methodology Physical surveys of the Lake Washington shoreline along the project boundary were undertaken to characterize existing conditions affecting fish habitat. A total of 4,890 feet of shoreline was walked from the northern edge of the Baxter property to the southern edge of the Barbee Mill parcel. The 19 June 1997 rA222sJlm1risa[e-ip2 Page 2-24 Figure 2-5 1994 beach seining results at Kennydale Park. 0 50 x En r 40 w 30 W 20 10 0 Feb Ou 50 x w 40 a a 30 w 20 10 0 Feb Mar Apr May Jun 1994 Mar Apr May Jun 1994 -0 SOCKEYE FRY -*-SOCKEYE PRESMOLTS -A -COHO H CHWOOK -'W YEU-OW PERCH -41M BASS --1 SQUAWFISH SM BASS Source: Muckleshoot 1997 Port Quendall Draft Mitigation Analysis Memorandum Table 2-8. Benthic biota present in Lake Washington within or near the project site. ..1.4-raw.. Chironomidae Macropelopia, Eukiefferiella, Heterotrissocladius, parakieffereriella, Chironomus, Cladopelma, Tanytarsus Cryplochironomous, Dicrotendipes, Einfeldia, Phaenopsectra Polypedilum midges Ceratopogonidae biting midges Oligochaeta Tubificidae, Naididae aquatic earthworms Nematoda roundworms Ostracoda seed shrimp Pelecypoda Pisidium freshwater clams Tricoptera caddisfiies Copepoda mainly harpacticoids Hydracarina Piona water mites Gastropoda Planorbella snails Amphipoda Hyalella azteca scuds and sideswimmers Ephemeroptera mayflies Pocoptera Perlodidae stoneflies Coilembola springtails Mysidacea Taphromysis seed shrimp Hirudinea leeches Tardigrada water bears Porifera sponges Brachiopoda daphnia lsopoda Caecidotea aquatic sowbugs Coleoptera Psephenus beetles Sources; Shepard and Hoeman 1979, Bennet and Cubbage 1992, 19 June 1997 r:12225JWfigafe-rpZ Page 2-26 Pori Quendall Draft Mitigation Analysis Meniorandiun remediation area stretches 3,130 feet along the shoreline of the Baxter and Quendall properties. A hip -chain was pulled to measure distances. Five variables (riparian vegetation, bank type, bank protection, substrate, and water depth) were assessed at roughly five-foot intervals. The dominant characteristic in each five foot interval was noted on a spreadsheet. Substrate and water depth were measured approximately five feet from shore. Overwater structures were also noted and measured. Existing literature was reviewed to describe shoreline characteristics in the immediate vicinity of the project. This information is provided for comparison with project site conditions. On -site Habitat and Valuatign Project shoreline characteristics are shown in Figures 2-2, 2-6 and 2-7. Features within the remediation area are summarized in Table 2-9. For this discussion, the remediation bounds are assumed to the shoreline of the Port Quendall and Baxter properties. Riparian vegetation is dominated by Himalayan blackberry (46°/a) which grows up to, and in places, over the lake. The remaining area is split about evenly between shrubs (primarily Scotch broom) and an unvegetated condition (Table 2-9). Approximately 25 percent of the shoreline is also overhung with a sparse tree canopy layer. Most trees are young alder (to about 8 inches DBH). The trees are typically set back from the shoreline five to ten feet and associated with the four lakeshore wetlands (Figure 2-2). No trees large enough to provide large woody debris (LWD) were noted. Wetland habitat influences approximately 17 percent of the shoreline (535 feet). The existing shoreline vegetation provides little visual refuge for fish, bank stability, insect habitat, or shading, because the lack of diversity and non-native characteristics of the existing vegetation are not well suited for these purposes. The young, sparse hardwood stand currently growing along the banks do not provide any of the above functions or serve as a source of large woody debris or bank refuge beneath undercut rootballs. 19 .tune 1997 r,U215JWdgafe.rp2 Page 2-27 BEACH LOG BOLLARD aVERTICAL DIRT to UNDERCUT w'l RIP -RAP .. LOGS IN LAKE C! BULKHEAD I NOTE: All habilat,weiland,end Provo lealate bcaflam and quantities are appmdmale_ ° LAVE Q 4 PORT 9UENDALL IlpS(!ER O/AA .-� PAN ABODE T q o a W 1 x 2 ��„ 71 Y-, ��jS u1r'l1 ,1�.� a co [gr- 1�X1�-- f n �i� n a., Port Quendall Draft Mitigation Analysis Memorandum Table 2-9. Lake Washington shoreline characteristics for the Quendall and Baxter Properties. �i a'r c eris is t o Vegetation none 800 26% blackberry 1425 46% shrubs 905 29% trees 770 25% wetland 535 17% Bank type/Protection beach 805 26% vertical dirt 930 30% rip -rap 415 13% bulkhead 0 0% log bollard 515 16% pier 55 2% building 35 1% log skid 35 1% undercut 110 4% inlet 820 26% logs 2550 81% Substrate' mud/silt 755 24% sand 1685 54% gravel 690 22% woodwaste2 500 16% Depth' 0-1 ft. 1775 57% 1-2 ft_ 870 28% >2 ft. 485 15% 3,130 feet, surveyed i t April 1997 ' Measured or sampled approximately five feet out from shoreline. Woodwaste — areas where chips and bark exceed 50% surface coverage. 19 June 1997 e_1222531mi[igaIe.rp2 Page 2-30 Port Quendal! Draft Mitigation Analysis Memorandum The majority of the bank (56%) is unsupported and consists of steep dirt banks from one to four feet high (30%), or relatively low gradient "beach" like shoreline (26%) (Figure 2-6). Manmade structures and protection features (rip -rap, log bollards, piers, buildings, log skids) cover 33 percent of the shoreline (Table 2-9). Eleven percent of the bank could not be surveyed due to heavy blackberry coverage. Four percent of the bank (110 feet) is undercut by wave action. Large logs floating or sitting on the bottom near the shore protect 81 percent of the shoreline. These logs not only shelter the banks from wave action, they provide excellent rearing and shelter habitat for fish and macroinvertebrates. Historically the lake shoreline was primarily low -gradient beach habitat formed as the delta of May Creek. Over time, erosion caused by industrial landfilling, riparian vegetation removal, and wave action has created oversteepened banks. Other banks are artificially protected with rip -rap and log bollards. Neither condition is conducive to habitat formation. Cull logs and stringers from the mill effectively provide many of the habitat functions and diversity normally associated with large woody debris (LWD). Various maiunade structures provide some diversity and overhead cover, and may be used by juvenile salmonids (Ratte and Salo 1985; Heiser and Finn 1970). Inlets, or coves make up approximately 26 percent of the shoreline. Most have a few pieces of LWD floating or sitting on the bottom. These areas of meandering shoreline add diversity to the relatively straight. shore elsewhere. Shallow coves filled with LWD could provide nursery areas for many species of fish and benthic organisms. Surficial substrate along the shoreline is dominated by sands (54%) with relatively equal proportions of mud/silt and gravel in other areas (Figure 2-7). None of the substrates are free of silts; a muddy layer underlies most areas. A large amount of woody debris including wood chips covered the substrate in several areas (Figures 2-4 and 2-7). 19 June 1997 rA2125AmWgale.rp2 Page 2-31 Port Quendall Draf! Mifigofion Analysis Memorandum Clean gravels can provide spawning habitat for sockeye as well as macroinvertebrate habitat. Finer materials anchor vegetation and are preferentially inhabited by other aquatic species. Dense wood chip coverage leads to anaerobic conditions and a relatively sterile environment. No benefit is derived from the wood chip coverage. Water depths five feet from shore are typically less than one foot (57%). Only 15 percent of the shoreline has a slope greater than about 3:1. These areas are usually heavily disturbed by nearshore activities and may have resulted from past filling of the lake. Anthropogenic structures are found in several areas along the shoreline. Two boat sheds (one sunken), half a dozen docks, a barge, three boats, two log skids and several other smaller structures impact approximately percent of the shoreline. All of these structures overhang shallow water habitat in Lake Washington. No floating log rafts were present offshore of Baxter or Quendall the day of the survey, although aerial photographs indicate this practice is common. The Gypsy Subbasin Drainage enters the Baxter property via a 24-inch concrete culvert beneath the Burlington Northern railroad tracks (Lntranco 1995). The culvert is 55 feet long, has a gradient of approximately 2 percent, and is likely an effective barrier to upstream fish passage. Upon entering the property, the drainage is discharged to a small (approximately 10 foot diameter),.quarry-spall lined pond. From the pond, the drainage enters a 24-inch, 46-foot long concrete culvert beneath a dirt haul road before daylighting again to an open channel. The open channel is a highly confined, steep -walled trough, approximately 10 to 15 feet below the surrounding ground elevation and 3 to 10 feet wide at the bottom. The substrate consists primarily of a deep anaerobic mud except where bank sloughing and rocks spilled into the channel have replaced the mud with a firmer bed material. The banks are heavily vegetated with a narrow strip of young hardwoods, scot's broom, and Himalayan blackberry. Total length of the open channel is approximately 125 feet. The drainage next enters a 490-foot, 24-inch CMP which discharges directly to Lake Washington. The 490-foot CMP drops approximately 0.5 foot (0.1 % gradient) and at low lake elevation is perched about a foot 19 June 1997 r_1122531mifigoftrp2 Page 2-32 Part Quendall Draft Miligalion Analysis Memorandtim above the lake water surface. During high lake elevations, the culvert is partially backwatered and upstream passage is possible, though not known to occur. Off -- Site Habitat A considerable amount of fisheries habitat information in South Lake Washington has been collected by the Muckleshoot Indian Tribe. Some of the data are summarized here to provide a comparison of on -site conditions with those found along the adjacent shoreline off -site. Shoreline composition was surveyed in September 1995 (Muckleshoot 1997). Percent bulkhead, sloped bank (beach), and vegetated distance was assessed between river mile (RM) 32 and RM 46. The Port Quendall remediation site (RM 37.9 - 38.5) was not surveyed due to access problems associated with the log booms. The data are plotted in Figure 2-8 with the 1997 remediation site information inserted in its appropriate location for comparison. Overall, the remediation site shoreline is in a much more natural condition than the surrounding shoreline (Table 2-10). Eighty-three percent of the shoreline surveyed by the Muckleshoot Indian Tribe has been bulkheaded while significantly less (33% total) of the remediation site has received similar treatment. Only 15 percent of the surrounding shoreline has low gradient banks and only two percent is vegetated (not including vegetated bulkheads). This compares with 26 percent low gradient bank and 60 percent vegetated bank for the remediation area. Table 2-1 O. Comparison of shoreline conditions within the remediation area and the surrounding shoreline. Bulkhead (%) 33 83 Sloped bank(beach (%) 26 15 Vegetated' %} 60 2 'Vegetated distance does not include vegetated bulkheads. 19 June 1997�_- 02113JUnkigafe.rp2 Page 2-33 Port Quendall Draft Mitigation Analysis Memorandum 100% 90% to a 80% z 70% a 60% A w 50�% - Remediation area - O' o 40% w 30% L] W 20% a 10% ❑ ❑ A ❑ 6// ❑ 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 LAKE MILE ♦ A BULKHEA❑ ❑% SLOPED ♦ % VEGETATED `r 11 5 Vi t E ` b-P- 0- U j w 91'&xik Figure 2-8. Lake Washington shoreline composition along a 14-mile reach of lakeshore on both Sides of Port Quendall in September 1995. 1Source: Muckleshoot 1997. c:U22JJ dgafe-rp1 Port Quendall Draft Mitigation Analysis Memorandum Pier coverage of the water surface within 100 feet of the shoreline was estimated from 1989 aerial photographs and a review of environmental documents published between September 1991 and July 1995 (Muckleshoot 1997). The values are believed to underestimate the real coverage due to an incomplete database and unauthorized development. For the eleven mile reach surveyed (which includes the remediation reach) a total of 517 piers were counted (47 piers/mile). This compares with 4 piers, or 7 pierslmile within the remediation reach (Table 2-11). Overall surface coverage averages 4.2 percent of the first 100 feet of lake for the eleven mile reach. Within the remediation area, only 0.6 percent of the lake surface is covered with piers. I Table 2-11. Comparison of overwater pier coverage within the remediation area (1997) and the I surrounding shoreline (1989), iraa it i .IC Number of Pierslniile 7 47 Estimated Coverage 3008 22368 Estimated Coverage (%) 0.6 4.2 1989 data supplied by the Muckleshoot Indian Tribe (Muckleshoot 1997). i 2.3.4 Late Washington Open Water enthi In general, the shoreline drops off gently at slopes between approximately 20:1 and 9:1. Small localized areas with slopes in excess of 3.1 are present. After dropping relatively quickly to 15 to 20 feet within 250 feet from shore, the gradient flattens into a broad plateau sloping gently for 19 June 1997 c_1122J3UWttga$e..p2 Page 2-35 Port Quendall Draft Mitigation kralysis Memorandum another 400 to 600 feet offshore. Approximately S to 10 additional feet in depth are gained over this plateau. Additional topographylbathymetry information and a map is provided in the Sediment Quality Memorandum, Section 4.1 (RETEC 1997). The vast majority of remediation activities will take place at 10 feet or less in depth, although dredging near the old T-dock would occur in about 30 feet of water. The surface of the lake bottom substrate was characterized in terms of particle size and organic material (e.g., wood chips). The sub -surface composition was examined via sediment -profile imaging (SPI). The surficial layer was surveyed with video by both towed and diver operated cameras, and during the SPI surveys. In general the lake bottom consists of very fine particles. Occasional sandy areas were also noted. No graveled areas were noted. A more complete description is provided in RETEC Section 4.2 (1997). SPI images provide a measurement of the substrate depth in which aerobic activity is occurring (RETEC 1997). These data are useful in assessing the quality of habitat for epifauna and infauna. A thin redox potential discontinuity (RPD) is indicative of stressed environment. Stress can occur physically (e.g., prop wash) or chemically (e.g., high biological oxygen demand or chemical contamination). RPD depths of less than 0.4 cm are indicative of an anaerobic condition. The shallowest RPD depths in the remediation area (<0.2 cm) were measured off the southern end of the Port Quendall parcel and were associated with areas with high wood waste (RETEC 1997, Figure 6-2). Intenned.iate RPD levels (0.2 to 0.8 cm) were observed over much of the rest of the lake bottom off Port Quendall. These levels are indicative of a disturbed environment where benthie stress is present but likely varies_ Both scattered wood debris and chemical contamination are likely present. The rest of the remediation area has RPD depths over 0.8 cm, which is considered to be a relatively undisturbed benthic condition in terms of overall animal -sediment interactions for nearshore environs in this portion of Lake Washington (RETEC 1997). A complete 19 June 1997 e:1111531mifigafe.rp2 Page 2-36 Port Quendall Draft Mitigation Analysis Memorandum description of the SPl process, wood and chemical contamination extents, and associated maps are provided in the Sediment Quality Memorandum, Section 6 (RETEC 1997). Sunken logs are present throughout the remediation area with the highest densities (3 to 5 logs/acre) mapped along the Quendall shoreline. Much of the aquatic organisms observed during video surveys (e.g., crayfish, sculpin, perch) were associated with the logs. Milfoil was noted during the side -scan sonar and video surveys (RETEC 1997). Areas of dense rnilfoil are mapped in Figure 2-2. Milfoil is common throughout most of the remediation area at water depths from about 4 to approximately 15 feet. Only in the dense woodwaste area at the south end of the.remediation area was milfoil relatively absent. Water Column Pilings and dolphins (tied piling cluster) are scattered throughout the remediation area with 64 percent located off the Port Quendall parcel. A total of 73 vertical structures, mainly dolphins, have been mapped to date. These structures provide vertical habitat which many species utilize, including some salmonid predators, (e.g., bass). Several hundred individual upright pilings, many not rising above the water surface, also likely exist but have not been mapped. The pilings also provide attachment and focal points for aquatic organisms such as freshwater mussels. Several sunken structures along the Quendall shoreline are also present in the water column including the old boat house and several partially sunken pier sections. Surfage A number of anthropogenic structures and objects exist on the surface of Lake Washington which have an influence on aquatic habitat quality. A varying quantity of logs have been stored as log 19 June 1991 c:122253Wfigarrp2 Page 2-37 Port Quendall Draft Mitigation Analysis Memorandum rafts off the shoreline of Barbee Mill, Baxter and Quendall. Vessels including tugs, barges and recreational. boats have been anchored in the area. Numerous docks are present in either a permanent (i.e., mounted on pilings) or temporary (i.e., floating) basis. Structures on the lake surface provide overhead refuge cover for numerous aquatic species as well as their predators. Salmonids in particular prefer overhead cover, especially when near shore. A number of small oily slicks have been observed nearshore and are believed to be coming from old creosote deposits (Figure 4-6 in RETEC 1997). These slicks impact aquatic habitat via both chemical and physical processes. Chemically, various components of the creosote are toxic to aquatic life. Physically, the slicks present a barrier at the aquatic/atmospheric interface. Fish feeding at the surface can become contaminated. Prey items stuck in the sheen are not consumable. 2.3.5 Habitat Valuation Numerous protected alcoves, abundant woody debris, overhanging trees, and relatively low human disturbance along the shoreline offer good potential rearing and migrating structure for fish, especially when compared to the adjacent Lake Washington shoreline. Although a number of beneficial habitat features exist, they are compromised by the constant seepage of chemicals and oily residues. Under existing conditions, therefore, habitat value of the remediation site for fish is low. Offshore habitat in the remediation area ranges from good to poor. Those areas contaminated with chemicals and wood clips offer poor to negligible.benthic habitat while pelagic species would be less affected. The majority of the lake bottom is relatively clean, however, and the numerous sunken logs provide good structural diversity for a number of aquatic species. The vertical and floating structures benefit some species (e.g., smallmouth bass) to the possible detriment of others (e.g., sockeye salmon). 19 June 1997 c:12225Amlligate,rp2 Page 2-38 Port Quendall Draft'Mitigation Analysis Menrorandurn Fish habitat value of the Gypsy Subbasin Drainage within the project boundary is minimal. The two short open stretches offer some potential rearing habitat, however, shallow depths, a muddy substrate, no instream structure, and little instream cover limits the overall habitat value. With little I protection from high velocities, winter storm events likely flusli many fish from the system. r Summer conditions produce extremely low flows which may also limit the habitat quality. 2.4 Recreational There is one private dock and boathouse located over Lake Washington at the extreme northern boundary of the Baxter parcel. Another private dock and boathouse exists at the extreme southern boundary of Barbee Mill. No other recreational opportunities and no public access are currently provided on the site. Recreational resources are not discussed further. 2.5 Cultural Reference Larson 1997 report to be completed and included with FS 2.6 Economic A portion of the Baxter parcel is used for storage of "beauty bark." The southern portion of the Quendall parcel is used for log sorting. Both of these uses would be curtailed by remediation. A utility right-of-way separates the Baxter and Quendall parcels, however use of this right-of-way is not affected by remediation. The Barbee Mill is active; however, this operation would not be impacted by remediation except for removal of wood chips offshore of Barbee, which likely would not occur until after mill operation ceased. Economic resources are not discussed further. 19 June 1997 e:U1153%midgafe rpl Page 2-39 Part Quendall Draft Mitigation Analysis Memorandum r t 3.0 IMPACTS 3.1 Remediation Alternative 1 - Low Impact No fill in Lake Washington is proposed under Alternative 1. 3.1.1 Plants and Animals D �tyrUance to Shoreline I Land -based remediation would result in the excavation and/or capping of the entire Quendall shoreline and approximately 970 feet of the Baxter shoreline (Figure 1-1). Approximately 1,630 linear feet of vegetated shoreline, including Wetlands A and B, would be removed (Table 3-1). This action would eliminate all wildlife use of the shoreline areas during active remediation, which is scheduled to begin in March 1998. Nesting waterfowl and passerine bird use would be the greatest wildlife use impacted during shoreline remediation activities. Table 3-1. Shoreline vegetation disturbance resulting from upland excavation and/or capping. ShoretiOkjGhArAgM1c:,,Ilm stied : -!'¢V;'? jc I �'t�"� Total shoreline impacted' 2430 feet Nonvegetated shoreline 800 feet Vegetated shoreline' 1630 feel blackberry 1260 feet upland shrubs 510 feet upland trees 680 feet wetland' 395 feet FAH dredging will disturb an additional 14U feet of shoreline_ I _ 19 June 1997 c:12115Jf Wj4zfe_rp2 Page 3-1 Port Quendall Draft Mitigation Analysis Menrorandaun Dredge_ Offshore PAH Wetland E (Baxter Cove) would be dredged to remove PAH sediments eliminating all vegetation (including 140 feet along the lake shoreline) and woody debris in the wetland and most of the adjacent vegetated buffer. Turtles would be displaced from this shoreline area during the dredging activities. Red -wing blackbird nesting habitat would be eliminated. PAH dredging off of the Quendall parcel would impact 1.55 acres ofmilfoil which is not considered to be a negative impact. Dredge of ire Areas with >50% Wood Cilips No impact to plants or animals would result from the removal of wood chips. Although approximately 0.44 acre of milfoil would be removed, this is not considered to be a negative impact. Upland Soil and Excavation and Cap�ina In addition to the removal of shoreline vegetation, all vegetated areas on the Quendall and Baxter parcels, including Wetlands C and D, would be eliminated with this action except for a 50-foot wide band along the north Baxter shoreline (Figure 1-1). This would eliminate all wildlife use of the Baxter and Quendall parcels upland of the shoreline areas. Snipes, Canada geese and some passerine birds have been observed using these sparsely vegetated areas. Osprey nesting in the area could be impacted by the remediation activities. However, the osprey successfully nested on the adjacent active mill site in 1997, indicating that high levels of activities and construction -level noise would not necessarily impact osprey nesting in this area. The occasional use of the osprey nest platform on the Puget Sound Energy cable station pole by bald eagles during the winter would likely be 19 June 1997 c 2225 midgare.rpl Page 3-2 Port Qrendall Draft Mitigation Analysis Memorandum eliminated during remediation activities. This very limited use should not affect bald eagle foraging. The closest known bald eagle nest site is approximately 3/4 mules west of the site, therefore, the project would not impact nesting bald eagles. Gypsy Subbasin Culvert Replacement The narrow band of willow and red alder along the 125-foot long open charuiel section of Gypsy Subbasin would be eliminated with this action. This action would not impact wildlife because of the disturbed and isolated condition of this small area. 3.1.2 Fisheries Shoreline Dittr -bance Shoreline disturbances affecting fish habitat include complete removal of all vegetation along the shoreline in the remediation area and 100 percent filling of Wetlands A and B, the two wetlands adjacent to the lake. Existing shoreline vegetation provides little habitat value for fish. Removal of all vegetation however, would further reduce nutrient input to the nearshore, decrease primary productivity for the area, and decrease the already minimal overhanging vegetation serving as refuge Habitat. Removal of the two wetlands would result in lost lakeshore habitat complexity including small patches of emergent vegetation, shallow nursery areas, and overhanging trees. A total of approximately 395 linear feet of shoreline wetland would be lost. Another approximately 140 feet of wetland shoreline at Baxter Cove would be severely impacted. Resulting shoreline vegetation condition for the three properties is shown in Table 3-2. 19 June 1997 e:122253imifigor«p1 Page 3-3 Table 3-2. Lake Washington Shoreline Fish Habitat Characteristics after Rernediation Alternative I - Low Impact Existing Conditions RemediaEed Conditions Fish . Linear Coverage Linear Coverage Change Habitat Category Characteristic Distance ft % Distance ft % % Goal Vegetation unvegetated 2460 50% 4230. 87% 72% - blackberry 1525 31 % 265 5 %v -83 % - shrubs 905 19% 395 8% -56% + trees 770 16% 90 2% -88% + . wetland 535 11 % 140 3% -74% =/+ Bank type/ beach 955 20% 955 20% 0% + Protection vertical dirt 1540 31 % 1540 31 % 0% - rip -rap 825 17 % 825 17 % .0% - bulkhead 340 7 % 340 7 % 0% log bollard 1015 21 % 1015 21 % 0% - pier 135 3% 135 3% 0% - building 60 1 % 60 1 % 0% - log skid 65 1 % 65 1 % 0% - undercut i 10 2% 110 2% 0% inlet 820 17 % 820 17 % 0% + logs 3400 70% 3400 70% 0% + Substrate' ntud/silt 1015 21% 825 17% -19% =/- sand 2505 51% 2465 50% -2% =1- gravel 730 15% 960 20% 32% =1+ woodwastez 1470 30% 0 1785 0% 37% -100% 0% - =�+ Depth' 0-1' 1785 37% 1-2' 1070 22% 1070 22% 0% =/+ 72' 2035 42% t 2035=1- Coverage includes Barbee Mill. Quendall, and Baxter shorelines in their entirety (4,890 feet of shoreline). Assumes no changes to shoreline features along Barbee Mill as remediation mitigation. ' Measured or sampled approximately five feet out from shoreline. = Woodwaste = areas where chips and bark exceed 50 percent surface coverage. Port Quendall Draft Mitigation Analysis Memorandum Shoreline disturbances are expected to discourage fish use of the area and possibly impact sockeye salmon migration habits. Both macro- and microinvertebrate populations will be impacted by loss of productivity from nearshore vegetation. fJredge Offshore (PAH) Offshore dredging of contaminated materials would result in immediate and severe direct impacts to benthic fauna during dredging activities. Fish use of the area would also be curtailed during dredging, and for a short time thereafter as the disturbed sediments settle after dredging equipment withdraws from the site. Timing of dredging activities could affect expected impacts as the area receives higher use during certain times of the year (e.g., sockeye migration periods). However, dredging would avoid critical periods as advised by WDFW, which has suggested closure of activity between 1 February and 15 July as a preliminary recommendation to protect migrating sockeye juveniles (Fisher, pers. comm.) Little beneficial habitat exists in the dredging areas, thus no long term negative impact is expected from the activity. Overall, dredging of these most highly contaminated sediments are expected to have a net long term benefit on fish habitat in the area. Once the dredged areas are refilled to their original contours with clean sediments, the areas are expected to be rapidly recolonized with benthic invertebrates and flora, and shortly thereafter the larger species which prey on these organisms. Contaminant exposure risk to the fishery should cease as a result of dredging, increasing the habitat value to. aquatic species. Although dredged silts and sands would be replaced with sand and gravel removed from the Cedar River, this is not considered a negative impact. The material was selected to maximize sediment variability in the region and with the hope that upwelling for sockeye spawning purposes may be facilitated. 19 June 1997 v 12 225 31 mitigate. rp 2 Page 3-5 Port Quendall Draft Mitigation Analysis Metnorandutn red e Qffshore (Wood Chips) Dredging of woodwastes would result in immediate and direct impacts to the minor benthic population present within locations exceeding 50 percent wood coverage (Figure 1-1). Fish use of the area would also be curtailed during dredging; and for a short time thereafter as the disturbed sediments settle and dredging equipment withdraws from the site. Timing of dredging activities . would affect expected impacts as the area receives higher use during certain times.of the year (e.g., sockeye migration periods), however dredging would avoid critical periods as advised by WDFW. Areas to be dredged of wood chips are commonly associated with highly anaerobic conditions (RETEC 1997), thus little beneficial habitat currently exists in the dredging areas. No long term negative impact is expected from the activity. Dredging of the wood chaps is expected to have a net long term benefit on fish habitat in the area. The areas are expected to be rapidly recolonized with benthic invertebrates and flora, and shortly thereafter with the larger species which prey on these organisms. Sublethal impacts to the fishery from the wood leachates and anaerobic chemical processes should decrease after dredging. Upland Soil Excavation and Capping Upland soil excavation and capping activities have the potential to introduce sediment to Lake Washington. Excessive sediment introduction can result in reduction of nearshore habitat availability. Excessive fine sediments can elevate turbidity which can have a detrimental effect on fish communities. High turbidity can impact fish directly through changes in behavior and physiology, or indirectly by decreasing food supply and habitat availability. Behavioral modifications include cessation of feeding and outmigration. Physical reactions include excessive mucus secretion, excretory interference and respiratory complications resulting in possible suffocation (Redding et al. 1987), 14 June 1497--- cA12253faridgutt..y2 Page 3-6 Port Quehdall Draft Mitigation Analysis Memorandum An erosion and sediment control plan would be developed and implemented to contain all significant sediment sources, thus no significant impacts to fish resources should be expected from the upland activities. Qvasy Subbasin Culvert Replacement I Construction activities related to the replacement of the Gypsy Subbasin culvert have the potential to impact fish in Lake Washington due to excessive sediment production. Sediment related construction impacts are discussed in the preceding section. Under existing conditions, fish are not able migrate from Lake Washington to fish habitat upstream of the culvert, therefore, it is unlikely fish are currently using the culvert in significant numbers. Replacement of the culvert with a larger pipe may increase the likelihood of migration upstream to the eastern project property boundary. An isolated, approximately 125-foot portion of the drainage which currently exists at the upstream end of the culvert would be replaced with an open 125-foot channel adjacent to Lake Washington (Figure 3-1). This section could, in the future, offer some rearing and possibly spawning benefits. Overall, upgrading the Gypsy culvert and relocation of the open channel to a more accessible location for fish is not expected to have a negative impact on fish. A long-term benefit to fish as a result of increased habitat availability due to the improved lake access, and enhanced passage to upstream habitat is expected. 19 June 1997 c:1222JAwWgaIerp2 Page 3-7 GYPSY SUBBASlN DRAINAGE DAYt1GHT1NG CONCEPT . 1. GYPSY SUSBASIN DRAINAGE 44 Vegetated riparian buf6 {Upland Mixed Forest Habitat) Low now la OHWIh Channel to contain up to the 100-rear flood event Wetland Habitat Lola: -end of Daylight Gppsr Subbasin oralrwge, create rearing habitat Ear fish Continues Continues to PORT QUENDALL REMEDIATAON PROJECT R013-1 CONCEPTUAL GYPSY SU88ASIN DRAINAGE STREAM & BUFFER DESIGN Port Qttendall Draft Mitigation Analysis Memorandtim 3.2 Remediation Alternative 2 - Medium Impact 3.2.1 Plants and Animals All plants and animal impacts are the same as Alternative 1 except for the loss of nearshore partially j submerged and floating logs that provide resting platforms for waterfowl and turtles along approximately 380 feet of the Quendall nearshore area within the 0.5-acre fill. 3.2.2 Fisheries Lake Fill New lake fill would directly remove 0.5 acres of lake habitat from Lake Washington behind a wall constructed to contain below ground contaminant seeps. This loss would consist of 0.4 acres of shallow water habitat (less than 4 feet) and 0.1 acre of deeper water habitat (4 to 6 feet). Four feet and shallower was selected to describe shallow water habitat because milfoil does not generally occur in this zone, thus the area provides maximum open water fish rearing and migrating conditions. The lake fill perimeter would have a 3:1 slope from the waterline into the lake, which is the angle of repose for the clean Cedar River sand and gravel to be used. At this angle, approximately 0.1 acres of new shallow water habitat would be created along the fill margin. Therefore, the total loss of lake habitat under this alternative would be 0.3 acres of shallow habitat i and 0.2 acres of deep water habitat. Use of shallow water habitat is dictated by species, and by lifestage within a species. For example sockeye fry are known to spend at least part of their time in the nearshore shallows after entering Lake Washington (Martz et at. 1996). Juveniles, smolts and adults generally prefer deeper waters. i 19 Jude 1991 cV115JymWSaIe.ry2 Page 3-9 Pori Quendall Draft Miligalion Analysis Memorandum Younger fish often utilize shallower waters to escape predators feeding offshore. The loss of 0.3 acres of nearshore shallow habitat along the Port Quendall shoreline, however, is not likely to significantly impact any species, but does represent a loss of potentially valuable aquatic habitat. Other impacts as a result of lake fill are noted in Table 3-3. These include increases in low gradient shoreline and nearshore graveled substrates, and decreases in mud/silt/sand substrates and woodwaste. All these changes are expected to be beneficial to fish habitat by increasing areas of preferred habitat and reducing results of past industrial land use activities. Negative impacts include a significant decrease in the number of logs along the shoreline and the unvegetated state of the shore. Qther Impacts All other disturbances and impacts would be identical to those described under Alternative l (Section 3.1). 3.3 Remediation Alternative 3 - High Impact 3.3.1 Plants and Animals All plants and animal impacts are the same as Alternative 1 except for the loss of nearshore partially submerged and floating logs that provide resting platforms for waterfowl and turtles along approximately 760 feet of the Quendall nearshore area within the 2.9-acre lake fill and the removal or fill of 2.19 acres of inilfoil within the lake fill and wood chip removal areas. 19 June 1997 c;121251Iff rigate✓p1 Page 3-10 Table 3-3. Lake Washington Shoreline Dish Habitat Characteristics after Reuiediation Alternative 2 - Medium Impact (0.5 acre fill) Existing Conditions Remediated Conditions Fish,:'F Linear Coverage Linear Coverage Change.: Habitat; Cate or Characteristic Distance ft % Distance ft % % "Goal ' Vegetation unvegetated 2460 50% 42.30', 87% 72%. blackberry 1525 31 % 265 5 % -83 % shrubs 905 19% 395 8% -56% + trees 770 16 % q :go 2 % - -88 % + wetland 535 11 % 140 3% =74% 1+ ? Bank typel beach 955 20% ":1300 27% 36% + Protection vertical dirt 1540 31 % 1540. 31 % 0 rip -rap 825 17% 825. 17%:; 0%. ' bulkhead 340 7 % 340 7 % 0% - log bollard 1015 21 % 1015 21 % 0% pier 135 3% _ 135 3% 0% - building 60 1 % 60 1 % 0% - tog skid 65 1 % 65 1 % 0% - undercut 110 2 % -110 2 % 0% _ inlet 820 17 % 820 17% 0% +' ' logs 3400 70% 2830 58% -17% + ''- Substrate' mud/sit( 1015 21% 825 17% -19910 =/- sand 2505 51 % 2410 49 % 4% =1- gravel 730 15% 1015 21 % 391% woodwastez 1470 30% 0 0% -100% Depth' 0-1' 1785 37% 1505 31% -16% 1-2' 1070 22 % 1350 28 % 26 % _ /+ >2' 2035 42% 2035 42% 0% Coverage includes Barbee Mill, Quendall, and Baxter shorelines in their entirety (4,890 feet of shoreline). Assumes no changes to shoreline features along Barbee Mill as remediation mitigation. Measuied or sampled approximately rive feet out from shoreline. Woodwaste = areas where chips and bark exceed 50 percent surface coverage. Port Quendall Draft Mitigation Analysis Memorandum 3.3.2 Fisheries Lake Fill New lake fill would directly remove 2.9 acres of lake habitat from Lake Washington. Unlike Alternative 2, this fill would consist of a confined disposal unit upland of the containment wall; however, the fill perimeter on the lake side of the wall would consist of the same 3:1 slope clean sand and gravel from the lake bottom to the waters surface. The total fill would consist of 0.8 acres of shallow water habitat (less than d feet) and 2.1 acre of deeper water habitat (4 to 18 feet). At the proposed fill angle, approximately 0.3 acres of new shallow habitat would be created along the fill margin. Therefore, the total loss of lake habitat under this alternative would be 0.5 acres of shallow habitat and 2.4 acres of deep water habitat. The 2.9 acres of fill under Alternative 3 would be a containment facility, precluding vegetation planting landward of the containment wall. The loss of 0.5 acres of nearshore shallow habitat along the Port Quendall shoreline represents a loss of potentially valuable aquatic habitat. Other impacts are noted in Table 3-4. These include increases in low gradient shoreline and nearshore graveled substrates and decreases in mud/silt/sand substrates and woodwaste. All these changes are expected to be beneficial to fish habitat. Negative impacts include a significant decrease in the number of logs along the shoreline and the unvegetated state of the shore. Other Impacts All other disturbances and impacts would be identical to those described under Alternative 1 (Section 3.1). 19 June 1997 0222531miligafe.rp2 Page 3-12 Table 3-4. Lake Washington Shoreline Fish Habitat Characteristics after Rernediation Alternative 3 - High Impact (2.9 acre fill) Existing Conditions Retnediated Conditions Fish Linear Coverage Linear Coverage Change; > Habitat Category Characteristic Distance 1t % Distance 1t % % `Goal' Vegetation unvegetated 2460 50% 4230 87% 72% blackberry 1525 31 % 265 5 % -83 % - shrubs 905 19 % ' 395 8 % -56 % +: trees 770 16% =90 2% 48% f wetland 535 11% 140 3% -74% =1+ Bank type/ beach 955 20% 1605 33% :68% Protection vertical dirt 1540 31 % 1540 31 % ` 0% rip -rap 825 17 % '825 17 % 0,% bulkhead 340 7 % 340 7 % 0% log bollard 1015 21% 1.015 21 % 0% pier 135 3% 11S 2% -15% - building 60 1 % 60. 1 % 0% - log skid 65 1 % 65 1 % 0% - undercut 110 2% .110 2% 0% _ inlet 820 17 % :820 17 % 0% + logs 3400 70% 2640 54% -22% f Substrate' mud/silt 1015 21 % 685 14 % -33% = /- sand 2505 51 % 2455 50% -2% =1- gravel 730 15% 1110 23% 52% =1+ woodwaste2 1470 30% 0 0% -100% - Depth' 0-1' 1785 37% 1265 26% -29% =1+ 1-2' 1070 22% 1590 33% 49% =1+ > 2' . 2035 42% 2035 42% 0% = 1- Coverage includes Barbee Mill, Quendall, and Baxter shorelines in their entirety (4,890 feet of shoreline). Assumes no changes to shoreline features along Barbee Mill as remediation mitigation. ' Measured or sampled approximately five feet out from shoreline. Woodwaste = areas where chips and bark exceed 50 percent surface coverage. Port Quendall Draft Mitigation Analysis Memorandum 4.0 MITIGATION Conceptual mitigation actions, are summarized in Table 4-1 and discussed below for each remediation action proposed under the three remediation alternatives. Constraints to mitigation are imposed by 1) the slurry or sheetpile wall under all alternatives, 2) creation of a 2.9-acre confined disposal unit as lake fill under Alternative 3, and 3) the Quendall and south Baxter upland excavation and capping areas (shown in blue over Quendall and south Baxter in figures 1-I through 1-3) under all alternatives. Creation of wetlands cannot occur upland of the wall and within the capped zone of Quendall and south Baxter under all alternatives. Vegetation cannot be planted on the 2.9-acre confined disposal unit under Alternative 3. 4.1 Rernediation Alternative 1 - Low Impact 4.1.1 Plants and Animals The wildlife habitat within the remediation area is primarily found along the shoreline. The goal of the wildlife mitigation is to expand and enhance the plant communities and other habitat features (e.g. down woody debris) along the Quendall and Baxter shorelines. Wetland communities would be replaced on a 1.1 basis (impact:created or restored) within Baxter Cove and another Iarge complex along the northern Baxter shoreline which would be connected to Baxter Cove via 0.25 acre of upland habitat along the shoreline. Wetland hydrology would be controlled by the lake. Vegetation and logs would provide shoreline protection as found under current conditions. Water quality functions would be limited in these wetland systems due to the, limited area that would drain into these wetlands, similar to existing wetland conditions. The biological support provided by the wetland mitigation areas is expected to be greater than currently provided by the five wetland areas that would be impacted by the remediation because a large wetland - upland complex would be established that supports greater vegetative diversity and structure, including an overstory conifer component. 19 Junc 1997 r3222331midgate rp2 Page 4-1 Port Quendall Draft Mitigation Analysis Memorandum Table 4-1. Summary of mitigation for impacts from each remediation alternative. Achon� _�\-, ; "Alternative'1 M ;?►1#ernative .R� lteraaahve3 • '' Aionpact Lake pill None (1) Replace and improve lost (1) Same as Alt 2, piis, (includes elimination of fish habitat value along the original shoreline through shoreline as feasible around (2) Create an additional 0.5 acre of fill area, reconstruction of the fill perimeter by wetland habitat along 360 feet of new shoreline around fill strategically anchoring logs Baxter shoreline; and perimeter at 3:1 slope; at the upper end of the 3:1 elimination of shallow and slopes to establish vegetation (3) Create an additional 0.35 acre of deep water lake habitat in (Figure 4-3); wildlife habitat adjacent to the area filled) wetland complex created on Baxter (2) Replace 0.3 acre of lost (may include the open channel section Mitigation constraint is shallow habitat by adding 0.3 of Gypsy Creek). sheetpile wall around fill acre of wetland along 200 perimeter. feet of Baxter shoreline adjacent to the wetland For Alternative 3, mitigation complex mitigating wetlands is constrained by inability to A-D; and plant landward of . containment wall around the (3) Replace lost deep water confined disposal unit. habitat by increasing shoreline complexity and vegetating 400 feet of non - vegetated shoreline. c:12215JImiAgaterp2 Port Quendoll Draft Miligation Analysis Memorandum Table 4-1. Summary of Mitigation Relationship to Impacts of each Alternative (Continued). kActioa 4 q d Altemat�ve 1 ,' , 1✓ow'Im act ,;� t Alternative 2 b? ,_ -. _ � .. ,. ediu rXm actHig ' Al#ernative`3ip '� , Li; y� c°.^. y j. +, -• hT p Disturbance to Shoreline (1) Replace and improve fish Same as Alternative 1, plus Same as Alternative 1, plus an (loss of vegetation, if any; habitat value along the shoreline an additional 625 feet of additional 1,095 feet of shoreline removal and/or f ll of upland by planting native vegetation, shoreline planted in trees, planted in trees. soils) increasing plant diversity and adding large woody debris for Mitigation constraint is nearshore complexity. sheetpile or slurry wall 20- (2) Replace Wetlands A and B 50- feet inland of OWM from with enhanced function and values Quendall-Barbee property on a 1.1 area basis in one wetland line northward to utility complex area associated with the ROW. lake (complex to include mitigation for wetlands C and D described below); (3) Enhance wetland buffers; (4) Connect Baxter Cove to wetland complex in north Baxter by 0.25-acre of native upland vegetation buffer along the lakeshore; and (5) Plant 80% of the combined Baxter and Quendall shorelines in native vegetation, with 30% of the combined shorelines including trees. ca222531mffrgafr rp2 Port Quendall Draft Mitigation Analysis Memorandum Table 4-1. Summary of Mitigation Relationship to Impacts of each Alternative (Continued). Action : Alternative 1 Low: impact Alternative2��{Alternative -;Medium r p 3 M� �$g�hnp`act ct Dredge offshore PAH (1) Replace Wetland E (Baxter Same as Alternative 1 Same as Alternative 1 (re -fill to original elevations Cove) in original location with with clean material) enhanced buffer; (2) No further action for other offshore dredge areas. Dredge offshore areas No Further Action No Further Action No Further Action with > SO% wood chips (with no re -fill; original elevations assumed prior to chip deposition). Upland soil excavation and (1) Replace Wetlands C & D with Same as Alternative 1 Same as Alternative 1 capping enhanced function and values on a 1:1 area basis in one wetland Mitigation largely complex area associated with the constrained to northern false (located in northern Baxter); Banter due to the degree of (2) enhance buffers; match prior contaminant removal and shoreline length of wetlands at capping to Quendall and minimum; southern Baxter. (3) If needed, a second osprey nest platform would be added at the north end of the mouth of May Creek. c:1111SAmWk4Ir "P1 Port Quendall Draft Mitigation Analysis Memorandum Table 4-1. Summary of Mitigation Relationship to Impacts of each Alternative (Continued). Action Alternative 1 L;aw,Impact .. Alternative 2 ;. Medium Impact Alternative 3 R =: 'High Isnpct 1 Gypsy subbasin culvert Replace culvert with larger Same as Alternative 1 Same as Alternative 1, however the replacement (replace with diameter pipe during open channel component may be lamer diameter under clean excavation and capping; increased as part of the 0.35-acre upland cap after excavation) possible realignment of culvert wildlife habitat addition to the but no longer than original; wetland complex. relocate existing open channel segment to lake -end of culvert. 25-ft buffer provided for open channel and culvert. t:11?2531mi1igate. rp2 Port QuendalI Draft Mitigation Analysts Memorandum Table 4-1. Summary of Mitigation Relationship to Impacts of each Alternative (Continued). Action Alternative 1 ,.:...Low Impact Alternative 2 Medium Impact Alternative 3 High )Impact. Gypsy subbasin culvert Replace culvert with larger Same as Alternative 1 Same as Alternative 1, however the replacement (replace with diameter pipe during open channel component may be larger diameter under clean excavation and capping; increased as part of the 0.35-acre upland cap after excavation) possible realignment of culvert wildlife habitat addition to the but no longer than original; wetland complex. relocate existing open channel segment to lake -end of culvert. 25-ft buffer provided for open channel and culvert. C 4222S31midgale.rp2 j Port Quendall Drafl Mitigation Analysis Memorandum Disturbance to Shoreline The following actions would be conducted to mitigate for shoreline wildlife habitat impacts: r • establish native plant communities along impacted shoreline that is currently 'vegetated; shrub species would be established along most of the revegetated shoreline, trees would be j established along at least 30 percent of the shoreline; I • at a minimum, vegetation would be established waterward of the slurry or sheetpile wall (Figure 4-1); • increase plant diversity from current conditions; • replace Wetlands A and 13 with enhanced functions on a 1:1 ratio (impact area: restoration area) in one -wetland complex associated with the lake (Figure 4-2); • length of the wetland complex along shoreline would at least equal current shoreline wetland area (--395 feet); enhance wetland by creating one larger system comprised of more diverse communities (e.g., conifers) integrated with other mitigation features (e.g., Gypsy Creek open channel); wetland hydrology would be controlled by lake level; + enhance vegetation component (species composition and diversity) of wetland buffer from current condition; • place woody debris in all re-created shoreline habitats; and • create 0.25 acre of native upland vegetated buffer along the lakeshore between Baxter Cove and north Baxter. 19 June 1997 c: L23753 Ingfig are. fp I Page 4-6 TA1S Wr f1 b1w �(n a S I eslablish upland or Welland woody vegetation I slurry V and tapped tonlainmenl wilh clean fill wall PORT QUENDALL REMEDIATION PROJECT KURE 4-1 CROSS SECTION THROUGH SLURRY CONTAINMENT WAIL (SHORELINE SECTIONS [MUDING LAKE FILL) PROJEU NO.: 222253 9 JUNE 1997 ( � _Upland buffer -------------------- Origino€ Topography TRAIL OBSERIATIDNIAREA VIEWPOINT shallow or deep formed and/or shrub -snub emergent communities wetlands w Seled'rrely plate woody debris in wetiand and huaer habitats to provide addilionai a wildlife habitat structure using hoih deciduous and coniferous lags rouging f ram r 10 3V dhh. Snags could also be installed. Provide overhang at shoreline edge with rsative willows, red osier dogwood, and other native species. Develop area of emergent vegetation as allowed by lake level fluctuation. r —Ux.W. (Elev 27) UKE ) WASHINGTON Remoye selected shoreline structures (rmueed piers and debris); and stroiegicolly place logs to protect the shoreline and add nearshore diversity. PORT QUENDALL REMEDIAT€ON PROJECT FIGUiIE 4.1 TYPJCAL CROSSSECTJON OF CONCEPTUAL WETLAND MIMAJTON DESIGN PROJECT NOYt 3 I 19JUNE1991 E.%nf*Ar Port Quendall Draft Mitigation Analysis Memorandum f?redge Offshore RAU Restore wetland habitat in Baxter Cove: • fill dredged areas with clean material to elevations similar to current conditions to recreate a hydrologic regime that supports open water and emergent vegetation components; the area would be capped prior to placement of suitable clean fill material; logs would be partially buried and/or anchored along the lake shoreline at the mouth of Baxter Cove to stabilize the shoreline and provide resting platforms for turtles and waterfowl; • float logs in open water area and place large down logs in wetland perimeter; + plant shallow and deep emergent wetland species to establish an emergent plant community with greater diversity than currently found in Baxter Cove; plant obligate and facultative wetland species at the wetland perimeter and plant a 25-foot forested and shrub upland buffer; and erect an osprey nest platform in the buffer if the cable station nest platform is removed during remediation; a nest platform would be placed at the northern mouth of May Creek prior to removal of the cable station nest platform if the existing platform were to be removed. Replace partially buried logs in the Quendall offshore PAH removal area. 19 June 1997 c,'U22SAmWgulup2 Page 4-9 Part Quendall Draft Mitigation Analysis Mein orandum Dredge Offibore Areasmith >50% Woo Chips No mitigation action required. UplandSQU and Excavation and Ca�}pi� Wildlife Habitat impacts would be compensated for in habitat created along the shoreline: • replace Wetlands C and D on a 1:1 area basis in one wetland complex associated with the Wetland A and B mitigation area along the lake in northern Baxter; • enhance the vegetation component (species composition and diversity) of the wetland and wetland buffer from current condition; and • place woody debris in wetland and associated buffer_ !aypsy_Subbasin Culvert Replacement The open charuiel section of Gypsy Subbasin would be relocated to the lake end of the drainage. Riparian vegetation (upland and/or wetland communities) would be established along the channel and would be contiguous with other wetland and shoreline mitigation features. This would greatly increase the wildlife habitat value of the open channel beyond its current low value and isolated conditions. 4.1.2 Fisheries Fish habitat mitigation for remediation impacts would take place along the Port Quendall and Baxter shorelines and is closely integrated with wetland mitigation activities. Mitigation planning is 19 June 1997-- e.1222531mi8gate.rp2 Page 4-10 Pori Quendall Draft Mitigation Analysis Memorandum directed towards creating a high quality nearshore rearing enviro«rnent as the first priority. General goals include increasing the length of shoreline vegetated with native shrubs and trees, increasing the diversity of habitat features along the shoreline, and minimizing anthropogenic impacts on the habitat (Table 4-2). Goals for each of the five major habitat attributes studied (riparian vegetation, bank type, bank protection, substrate, depth) and the 23 measured variables are provided in Table 4-3 in the Fish Habitat Goal coluinn. One of the primary sources of mitigation is the creation of new shoreline wetlands. These were chosen for their intrinsically high Habitat value to both fish and wildlife. Wetland size, buffer width, vegetation quantity, and inwater complexity would increase with increasing remediation impacts. Increasing vegetation along the shoreline, increasing inwater habitat features (bank characteristics, substrate type, cover features) and removing anthropogenic impacts (structures, bank protection features) were also selected as habitat improvement opportunities. Justification and expected benefits for habitat characteristics chosen for mitigation is provided in Table 4-2. The quantity of mitigation would increase with increasing remediation disturbance. Since relatively little impact is expected as a result of Alternative 1, mitigation goals are simply to replace any valuable features lost during remediation (e.g., wetlands) and enhance those areas where complementary with project goals (e.g., vegetation and tree plantings along the shoreline). Ancillary benefits are expected as a direct consequence of remediation (e.g., reduction of fine sediments in nearshore substrate, removal of abandoned inwater structures). As impacts increase, mitigation efforts are expanded using the goals delineated in Table 4-3. Lake Fill No fill in Lake Washington is proposed under Alternative 1. 19 June 1997 r:11115.iinri[itare.rp2 Page 4-1 1 Port Quendall Draft 1firigarion Analysis Memorandum Table 4-2. Fish habitat -valuation of physical shoreline characteristics in rernediation area. Characteristic Fish Habitat Value Current Condition Mitigation Opportunities .Vegetation Low growing vegetation including grasses and shrubs Shrubs dominated by non-native Increase vegetated shoreline length; provide overhanging visual refuge for fish, bank Scotch broom and Himalayan include groundcovers, shrubs, and stability, insect habitat (prey item), and shading; trees blackberry to the exclusion of native trees; reduce dominance of non - provide similar functions plus source of large woody species; small hardwoods; relatively native species. debris, and overhanging banks when rootball is homogeneous structure. undercut. . Bank Type Historically the lake shoreline was primarily low- Beach type shoreline dominates. Shoreline dominated by beach gradient beach habitat formed as the delta of May Anthropogenic features (e.g. piers, habitat/wetland; other shoreline Creek; LWD near beach may provide juvenile salmon bollards, etc.) are also common. features (e.g. rocks, logs) included refuge. Alternative shoreline types (e.g. bollards, rip- Eroding dirt along shoreline at in minor proportions for diversity. rap) provide diversity and rearing habitat for juvenile southeast. salmonids. Bank Protection Fallen trees along the shoreline provide bank Approximately 15% anthropogenic Remove/minimize anthropogenic stabilization as well as quiet backwater rearing habitat structures; logs along 86% of shoreline protection; for juveniles. Logs enhance primary productivity in shoreline and in shallow nearshore maintainlincrease downed log nursery areas. Rocks and rootwads provide refuge and lake environment. numbers within nearshore area. habitat diversity. Substrate Clean gravels provide potential spawning habitat for Dominated by fine materials Increase proportion of clean salmonids as well as macroinvertebrate habitat; finer including sand and silts; graveled gravels; remove wood chips as materials anchor vegetation land are preferentially substrate around 12% of shoreline; practicable. inhabited by other aquatic species; dense wood chips abundant wood chips in areas. provide no benefit. Depth Juvenile salmonids prefer nearshore shallow habitat at Mostly (69%) very shallow Maintain high shallow area night; deeper areas provide adult holding and refuge nearshore environment (<1 foot component consistent with historic especially when combined with overhanging banks or within 5 feet offshore). Occasional delta habitat; provide deeper areas other complex structures. Intermediate depths for deeper areas. for diversity, vegetation, t1232531MWgafe rp1 r Table Late Washington Shoreline Fish Habitat Characteristics after Remediation and Mitigation Alternative 1 - Low Jtnpact Existing Conditions Remediated Conditions Fish Mitigated Conditions Linear Coverage Linear Coverage Change Habitat Linear Coverage Change from Change from Category Characteristic Distance ft % Distance ft % % Goal - Distance ft % Remediated Existine Vegetation unvegetated 2460 50 % 4230 87 % 72 % 2286 47 % -46 % _7% blackberry 1525 31 % 265 5 % -83 % - 100 2 % -62 % -93 % shrubs 905 19 %. 395 8 % -56 % + 2504 51 % 534 % 177 % trees 770 16 % 90 2 % -88 % + 939 19% 943 % 22 % wetland 535 11 % 140 3% -74 % =1 + 535 11 % 282 % 0% Bank type! beach 955 20 % 955 20 % 0% + 1355 28 % 42 % 42% Protection vertical dirt 1540 31 % 1540 3 t % 0% - 1380 28 % -10 % -10 % rip -rap 825 17 % 825 l 7 % 0% - 743 15 % -10 % -10 % bulkhead 340 7%, 340 7% 017. - 340 7% 0% 0% log bollard 1015 21 % 1015 21 % 0% 770 16 % -24 7 -24 % pier 135 3% 135 3% 0% - 100 2% -26% -26% building 60 1 % 60 1 % 0% - ... 60 1 % ...0% 0 % log skid 65 1 %4 65 1 % 0% 30 1 % -54 % . =54 % undercut 110 2 % 110 2 % 0% —. 110 2 % 0% .0% inlet 820 17 % 820 17 % 0% + ., 1150 24 % _ 40 % ::: - 40 % logs 3400 70% 3400 70% 0% + 3400 70% 0% 0% Substrate' mud/silt 1015 21 % 825 17 % -19 % =1- 825 17 % 0% -19 % sand 2505 51 % 2465 50 % -2 % =1- _ 2320 47 % =6 % 4% gravel 730 15 % 960 20 % 32 % =1+ 1105 23 % 15 % 51 % woodwaste' 1470 30 % 0 0%, -100 % - 0 0% 0% -100 % Depths 0-1' 1785 37% 1785 37% 0% =1+ 1785 37% 0% 0% 1-2' 1070 22 % 1070 22 % 0% -1+ , 1070 22 % , 0 % :. 0% 72' 2035 42% 2035 42% 0%n =1- 2035 42% 0% 0% Coverage includes Barbee Mill, Quendall, and Baxter shorelines in their entirety (4,890 feet of shoreline). Assumes no changes to shoreline features along Barbee Mill as remediation mitigation. ' Measured or sampled approximately five feet out from shoreline. Woodwaste = areas where chips and bark exceed 50 percent surface coverage. Port Quendall Draft Mitigation Analysis Meimorandant horeline Disturbance Vegetation removal would be mitigated by replanting the nearshore environment. The riparian width would vary based on the location of project features (e.g. walkways), but where credited for mitigation would be a minimum of 20 feet_ A minimum of 80 percent of the Port Quendall and Baxter shoreline (2,500 feet) would be planted with low growing native ground -covers and shrubs. Plants along the shore would be selected to maximize overhanging vegetation and provide bank stability. A minimum of 30 percent of the Port Quendall and Baxter shoreline (939 feet) would be planted with trees (tree planting would be concurrent with other shrub and ground -cover vegetation). Trees close to the waterline would be selected to provide similar functions to those described for the shrubs. Mitigation for loss of nearshore wetlands is described in Section 4.1.1. New wetland locations were selected along the Baxter shoreline to replace areas with relatively poor fish habitat conditions (e.g., vertical dirt banks, abandoned structures, rip -rap). Wetland replacement would result in increased low -gradient shoreline and a more diverse shoreline structure (Table 4-3). Reductions in the extent of vertical dirt bank, rip -rap, log bollards, and industrial structures (concrete pier mid -Baxter; log skid north-Quendall) would be accomplished (Table 4-3). Dredge Offshore (PAH and Woad Chips) No direct mitigation is proposed for offshore dredging undertaken to remove PAH and wood chip contamination except for re-establishing the Baxter Cove shoreline to its original value (included in Table 4-3). 19 June 1997 c.U225Awitigatarp2 Page 4-14 Port Quendall Draft Mitigation Analysis Memorandum jUpland i cavati n and Ca in Potential upland soil excavation and capping impacts would be mitigated to the greatest extent practicable with implementation of an erosion and sediment control plan. No other mitigation is proposed. Gypsy Subbasin CulyW RePlacernent Activities surrounding replacement of the Gypsy subbasin culvert with a larger diameter culvert would provide direct benefits to the fish resource by enhancing upstream and downstream fish passage and directly connecting 125 feet of fluvial habitat to the lake. No additional mitigation is proposed. 1 4.2 Alternative 2 - Medium Impact 4.2.1 Mitigation Mitigation features described herein are in addition to those already proposed under Alternative 1. The following actions would be implemented to compensate for the approximate 0.5-acre lake fill. Lake Fill + the wetland complex in north Baxter would be enlarged by 0.3 acre along a 200-foot length of Baxter shoreline; 0 an additional 250 linear feet of large woody debris would be incorporated into the shoreline for fisheries; 19 June 1997 c.t111JJindfigafe.rp2 Page 4-15 1 Port Quendall Draft Mitigation Analysis Memorandum + shrub communities would be created along 400 feet of nonvegetated shoreline (minimum I width 20 feet); and I • an additional 625 linear feet of tree plantings (concurrent with shrubs) would be added along the shoreline (50 percent of shoreline would support tree plantings). 4.2.2 Plants and Animals All wildlife mitigation actions proposed for Alternative 1 would be implemented as described in i Section 4.1. l for each remediation action, as well as the out -of -kind actions described above that would be implemented to compensate for lake fill impacts. An increase in wildlife habitat value i would be realized with these actions. I No other mitigation is proposed under Alternative 2. 4.2.3 rislieries j,—ake Pill The goal of mitigation for the lake fill is to replace lost shallow water habitat (less than 4 feet in depth) with shallow habitat of higher value to juvenile salmonids and their prey, and to replace lost deepwater habitat with other not -in -kind shoreline improvements beneficial to fish and aquatic dependent wildlife. The loss of 0.3 acre of shallow lake habitat would be mitigated in part by creating an additional 0.3 acre of wetland along 200 feet of the Baxter property shoreline (Section 4.2.1). The wetland would 19 June 1997 r:v11531midga[e.ry1 Page 4-16 Port Quendall Draft Mitigation Analysis Mentorandion be designated to maximize potential use by juvenile fish. Open water areas with abundant l vegetation, overhead cover, and large woody debris would be created in an area of straight shoreline with little habitat value. The additional shoreline wetland would more than double the quantity found under existing conditions; increased in shoreline diversity, woody debris, graveled substrate, and vegetative cover would also occur (Table 4-4)_ All features are expected to benefit juvenile fish, particularly those species such as sockeye which spend a considerable amount of time rearing in Lake Washington and utilize refuge habitat currently in short supply along the southeast perimeter of the lake. The 0.2 acre of lost deep water habitat is difficult to replace in kind and would provide only minimal liabitat benefits when compared to other improvements available along the nearshore environment. Therefore, to mitigate lost deep water habitat, increased shoreline and wetland habitat complexity would be provided. Additional large woody debris would be strategically placed along the shoreline to increase rearing and refuge habitat, stabilize banks, and establish vegetation (Figure 4-3). Additional riparian vegetation would be planted along the shoreline. !atheL Impacts All other impacts would be mitigated as described under Alternative 1 (Section 4.1.2). 4.3 Remediation Alternative 3 - High Impact 4.3.1 Mitigation Mitigation features described herein are in addition to those already proposed under Alternatives 1 and 2. 19 June 1997 cU2253U 61afe.►p2 • Page 4-17 4! -4 Table-+-3. Lake Washington Shoreline Fists Habitat Characteristics after Remediation and Mitigation Alternative 2 - Medium Impact (0.5 acre fill) Existing Conditions I Remediated Conditions Fish Miti aced Conditions Linear Coverage Linear Coverage I Change Habitat Linear Coverage Change from Change from Category Characteristic Distance ft % Distance ft % % Goal Distance ft % Remediated Existing Vegetation unvegetated 2460 50% 4230 87 % 72% - 1886 39% -55 % -23 % blackberry 1525 31% 265 5 % -83 % - 100 2% -62 % -93 % shrubs 1 905 19 % 395 8 % -56 % + 2904 59 % 635 % 221 % trees 770 16 % 90 2% -88 % + 1565 32 % 1639 % 103 % wetland 535 11% 140 3% -74% =/+ 1155 24% 725% 116% Bank type/ beach 955 20 % 1300 27 % 36 % + 2575 53 % 98 % 170 % Protection vertical dirt 1540 31% 1540 31% 1 0% - 1030 21 % .33 % -33 % rip -rap 825 17 % ! 825 17 % 0% - 525 11 % -36 % -36 % bulkhead I 340 7 % 340 7 % 0 % - 340 7 % 0% 0% log bollard 1015 21 % 1015 21 % 0% - 650 13 % -36 % -36 % pier 135 3 % 135 3 % .0% 100 2% -26 % -26 % building 60 1 %60 i % 0% - 60 1 % 0% :0% log skid 65 1 % 65 1 % 0% 15 0% -77.% -77 % undercut 110 2% 110 2% 0% 110 2% 0% U% inlet 820 17 % 820 17 % 0%.. + 1770 36 % 116 % 116% logs 3400 70 % 2830 58 % -17 % + 3 650 75 % 29 % 7 % Substrate' mud/silt 1015 21 % 825 17 % �19 % -!- 755 15 % -8 % -26% sand 2505 51 % 2410 49 % =4 % _ /- 1945 40 % -19 % -22 % gravel 730 15% 1015 21% 39% =1+ 1550 32% 53%. 112% wondwaste2 1470 30% 0 0% -100% - 0 0% 0% -100% Depth' 0-1' 1785 37% 1505 31% =16% =/+ 1505 31% ;0% '-16% 1-2' 1070 22 % 1350 28 % 2617. - l+ : 1350 28 % 0% 26 % > 2' 2035 42 % 2035 42 % 0% = /- 2035 42 % 0% 0% Coverage includes Barbee Mill, Quendall, and Baxter shorelines in their entirety (4,M feet of shoreline). Assumes no changes to shoreline features along Barbee Mill as remediation mitigation. Measured or sampled approximately five feet out from shoreline. 2 Woodwaste - areas where chips and bark exceed 50 percent surface coverage. I hi. s wv�l. 6-Q- PORT QUENDALL REMEDIATION PROJECT FIGURE 4-3 CROSS SEMON THROUGH CONTAINMENT WALL FOR LAKE FILL, ALTERNATIVES 2 & 3 PROJECT NO.-. 222253 19 JUNE 1497 SH1PILMMI P CHECKED: JBE .. ::� Part Quendall Draft Mitigation Analysis Memorandum Lake Fill • the wetland complex in north Baxter would be enlarged by an additional 0.5 acre along a - 360-foot length of Baxter shoreline; 0 0.35 acre of wildlife habitat would be created adjacent to the wetland complex created on Baxter; • . an additional 250 linear feet of large woody debris would be incorporated into the fisheries habitat enhancement features; and 0 an additional 470 linear feet of tree plantings (concurrent with shrubs) would be added along the shoreline (65% of shoreline would support tree plantings). 4.3.2 Plauts and Animals All wildlife mitigation actions proposed for Alternatives 1 and 2 would be implemented as described in Sections 4.1.1 and 4.2.1. The additional out -of -kind actions implemented to compensate for the larger lake fill would also provide additional wildlife benefits. 4.3.3 Fisheries Lake Fill Mitigation for the lake fill proposed under Alternative 3 includes all. those features described under Alternative 2 (Section 4.2.1), with further increases in the quantity of each mitigation feature 19 June 1997 c:12z25-IIM rate-rp2 Page 4-20 Port Quendall Draft Mitigation Analysis Menroranduni including wetland creation (0.3 acre) to help offset the loss of deepwater habitat (Table 4-5). An additional 0.5 acre of shoreline wetland habitat would be created to replace the 0.5 acre of shallow water habitat being filled. Shoreline diversity, woody debris, graveled substrate, and vegetative cover would also increase substantially. A small loss of undercut bank (80 feet) would result as the vertical dirt walls in which the undercuts currently occur are replaced with wetlands. The habitat value provided by overhanging banks would be replaced with overhanging woody debris placed along the shoreline to create usable overhead cover for fish. Where practicable, competent logs found on the bottom of Lake Washington in the areas to be dredged would be saved and restored to the lake bottom after capping. ther InIpact5 All other impacts would be mitigated as described under Alternative 1 (Section 4.1.2). 19 June 1997 e:1I12jAmNgale,rp2 Page 4-21 Table 44: Lake Washington Shoreline Fish Habitat Characteristics after Remediation and Mitigation Alternative 3 - High impact (2.9 acre fill) Existing Conditions Remediated Conditions Fish Mitigated Conditions Linear Coverage Linear Coverage Change Habitat Linear Coverage Change from Change from Category Characteristic Distance ft % Distance ft % % Goal Distance ft % Remediated Existing Vegetation unvegetated 2460 50 % 4230 87 % 72 % - 1886 39 % -55 % -23% blackberry 1525 31 % 265 5 % -83 % - 100 2 % -62 % -93 % shrubs 905 19 % 395 8 % -56 % + 2904 59 % 635 % 221 % trees 770 16 % 90 2 % -88 % + 2035 42 % 2161 % 164 % wetland 535 11 % 140 3 % -74% =/+ .. 1515 31 % 982% 183% Bank type! beach 955 20 % 1605 33% 68 % + 3230 66 % 101 % 238 % Protection vertical dirt 1540 31 % 1540 31 % 0% 700 14% -55 % -55% rip -rap 825 17 % 825 17 % 0% - 435 9 % -47 % �47 % bulkhead 340 7 % 340 7 % 0% - 340 7 % 0% 0%. log bollard 1015 219 1015 21% 0% - 650 13% . -36% -36% pier 135 3 % 1 115 2 % -15 % - 80 2 % -30 % -41. % building 60 1% 60 1% 0% : 60 1% 0% 0% log skid 65 1% 65 1% 0% - 15 0% -77% -77% undercut 110 2 % 114 2 % 0% — 30 1% -73 % -73 % inlet 820 17 % $20 17 % 0 9b + 2130 44 % 160 % I60 to s 3400 70 % 2640 54 % . -22 % + 3900 80 % 48 % 15 % Substrate' mud/silt 1015 21% 685 14 % -33% ; 1 .:, 615 13 % . - -10 % .-39 % sand 2505 51% 2455 50% -2% 1 1930 39% -21% -23% gravel 730 157. 1110 23% 52% /+° 1705 35% 54176 134% woodwaste-I 1470 30% 0 0% -100% 0 0% 0% - =100% Depth' 0-1' 1785 37% 1265 26% -29% _/+, 1265 26% 0% - -29% 1-2' 1070 22% 1590 33% 49% =1+ : 1590 33% :Q% 49% > 2' 2035 42 % 2035 42 % 076 1- ' 2035 42 % 0% 0% Coverage includes Barbee Mill, Quendall, and Baxter shorelines in their entirety (4,890 feet of shoreline), Assumes no changes to shoreline features along Barbee Mill as rcmediation mitigation, Measured or sampled approximately five feet out from shoreline. z Woodwaste = areas where chips and bark exceed 50 percent surface coverage, Port Quendall Drafi Mifigarion.4nalysis Memorandiun 5.0 REFERENCES Bennett and Cubbage 1992. Effects of polycyclic aromatic hydrocarbons from Lake Washington on freshwater bioassay organisms and benthic macroinvertebrates. Ecology Report, 28 p. plus appendices. Bennet, J. and J. Cubbage. Effects of polycyclic aromatic hydrocarbons (PAHs) in sediments from Lake Washington on freshwater bioassay organisms and benthic macro invertebrates. Report produced for the Sediment Management Unit, Washington Department of Ecology Environmental Investigations and Laboratory Services Program, Toxics, Compliance, and Groundwater Investigations Section, Olympia, Washington. Burgner, R.L. 1991. Life history of sockeye salmon (Oncorhynchus nerka). Pages 3-117 in: Groot, C. and L. Margolis, eds. 1991. Pacific salmon life histories. UBC Press, Vancouver, British Columbia, Canada. Entranco. 1995. Gypsy subbasin analysis, tecluvcai memorandum No. 2. Prepared for the City of Renton, Washington. David Evans and Associates, Inc. 1997. Wetland determination report on the JAG Development Property, Renton, Washington. Prepared for CNA Architecture Group, Bellevue, WA. Fisher, L., Washington Department of Fish and Wildlife. Personal communication to Andy Kindig (Beak), 6 June 1997. 4 Heiser, D. W. and E. L. Firm, Jr. 1970. Observations of juvenile chum and pink salmon in marina and buikheaded areas. Supplemental progress report, Washington State Department of Fisheries. September 1970. 28 p. King County. 1993. Sammamish River corridor conditions and enhancement opportunities. King County Surface Water Management, Seattle, WA. 54 p. plus appendices. Muckleshoot Indian Tribe. 1997, Draft summary of Lake Washington studies completed by the Muckleshoot Indian Tribe in the vicinity of the Port Quendall project. Provided by Rod Malcom, habitat biologist. Muckleshoot Indian Tribe, Environmental Division, Auburn, WA. 19 June 1997 c.U21SJWdga1e-rp2 Page 5-1 Part Quendall Draft Mitigation Analysis Memorandum Municipality of Metropolitan Seattle (Metro). 1989. Quality of local lakes and streams 1987-1988 status report. Municipality of Metropolitan Seattle, Water Resources Section, Water Pollution Control Department, Seattle, WA. Norton, 1991. Distribution and Significance of Polycyclic Aromatic Hydrocarbons in Lake Washington Sediments Adjacent to Quendall Terminals/ J.H. Baxter site. Ecology Report, 73 p. Norton, 1992. Results of Sediment Sampling in the J.H. Baxter Cove, Lake Washington - June 1991. Ecology Technical Document, 18 p. Pfeifer, B. and J. Weinheimer. 1992. Fisheries investigations of Lakes Washington and Sammamish, 1980-1990. VI Warmwater fish in Lakes Washington and Sar mamish (draft report). Washington Department of Fish and Wildlife, Olympia, WA. Ratte, L. D. and E. O. Salo. 1985. Under -pier ecology of juvenile pacific salmon (Oneorhynchus spp.) in Commencement Bay, Washington. Final report prepared by the University of Washington, Fisheries Research Institute for the Port of Tacoma. FRI-UW-8508. December 1985. RETEC. 1997. Sediment quality memorandum. Consultant report prepared for Port Quendall Company. 29 April 1997. Remediation Technologies, Inc., Seattle, Washington. Shepard, M.F. and J.C. Hoeman. 1979. Some comparisons of benthis biota in control areas and areas affected by sewage effluent in Lake Washington, 1977 - 1978. U.W. College of Fisheries, Wa, Coop. Fish. Res. Unit, Seattle, WA. citation from EVS Consultants, 1990. Aquatic Resources of Lake Washington. Report prepared for Woodward -Clyde Consultants, Seattle, WA. 19 November 1990. University of Washington. 1996. U.W. Lake Washington Sockeye Workshop. Notes from presentations by Roger Tabor (USFWS), Roland Viera (U.W.) and Tom Sibley (U.W.) at U.W. conference held 19 November 1996. Washington Department of Ecology. 1995. 1994 Washington state water quality assessment, [305(b)] report companion document. Olympia, WA. Washington Department of Ecology. 1996. 303(d) Department of Ecology draft decision matrix for surface waters listed under section 303(d) included in 305b Report of the Federal Clean Water Act (CWA). Washington Department of Ecology, Olympia, WA. 19 June 1997 6222331mWSo1e.ry2 Page 5-2 Port Quendall Drafi Mitigation Analysis Memorandum Washington Department of Fish and Wildlife and Western Washington Treaty Indian Tribes. 1994. 1992 Washington State salmon and steelhead stock inventory, Appendix I., Puget Sound stocks, South Puget Sound volume. WDFW, Olympia, Washington. Wydoski, R.S. and R.R. Whitney. 1979. Inland fishes of Washington. University of Washington Press, Seattle, WA. 220 P. 19 June 1997 cAMS31mifigalury2 Page 5-3 WASHINGTON STATE DEPARTMENTOF Natural Resources May 19, 1997 Frederick Huston Beak Consultants Inc 12391 - 126th Place NE Kirkland WA 98034 JENNIFER M_BELCHER Commissioner of Public Lands KALEEN COTCINGHAM Supervisor MAY 2 8 1997 13CA`° SUBJECT: Port Quendall, Renton, WA - (T24N R05E S29 & 32) Beak Project #22223 We've searched the Natural Heritage Information System for information on significant natural features in your study area. Currently, we have no records for rare plants or high quality ecosystems in the vicinity of your project. The Washington Natural Heritage Program is responsible for information on the state's endangered, threatened, and sensitive plants as well as high quality ecosystems. The Department of Fish and Wildlife manages and interprets data on wildlife species of concern in the state. For information on animals of concern in the state, please contact Priority Habitats and Species, Washington Department of Fish and Wildlife, 600 Capitol Way N, Olympia, WA 98501-1091, or by phone (360) 902-2543. The information provided by the Washington Natural Heritage Program is based solely on existing information in the database. In the absence of field inventories, we cannot state whether or not a given site contains high quality ecosystems or rare species; there may be significant natural features in your study area of which we are not aware. I hope you'll land this information helpful. Sincerely, f fI ►I rl►� Sandy Swope Moody, Environmental Coordinator Washington Natural Heritage Program Division of Forest Resources PO Box 47016 Olympia WA 98504-7016 (360) 902-1667 FOREST RESOURCES DIVISION PO BOX 47016 • OLYMPIA WA 98504-7016 PHONE 360-902-1340 FAX 360-902-1783 1111 WASHINGTON 5T SE ! PO BOX 47000 I OLYMPIA, WA 98504.7000 ®131W 11 Equal oppvrtunitylAffirmative Action Employer RECYCLED PAPERCJ Qa �� United States Department of the Interior 3 n FISH AND WILDLIFE SERVICE North Pacific Coast Ecoregion �1�f 1�' Western Washington Office" j 510 Desmond Drive SE, Suite 102 Lacey, Washington 98501 Phone: (360) 753-9440 Fax: (360) 753-9008 June 3, 1997 Frederick L. Huston, Jr. Beak Consultants Incorporated 12931 Northeast 126" Place Kirkland, Washington 98034-7715 FWS Ref: 173-97-SP-395 Dear Mr. Huston: This is in response to your fax dated May 9, 1997, and received in this office on that date. You have requested a list of Federally listed and proposed threatened and endangered species, candidate species and species of concern (Attachment A) that may be present within the area of the proposed Port Quendall Development Project on Lake Washington in King County, Washington. This list reflects changes to the candidate species list published February 28, 1996, in the Federal Register (Vol. 61 No. 40, 7596) and the addition of "species of concern" prepared by the U.S. Fish and Wildlife Service's (Service) Western Washington Office. The list fulfills the requirements of the Service under section 7(c) of the Endangered Species Act of 1973, as amended (Act). We have also enclosed a copy of the requirements for Army Corps of Engineers (COE) compliance under the Act (Attachment B). Should the COE determine that a listed species is likely to be affected (adversely or beneficially) by the project, you should request section 7 consultation through this office. If the COE determines that a proposed action is "not likely to adversely affect" a listed species, you should request Service concurrence with that determination through the informal consultation process. Even if there is a "no effect" situation, we would appreciate receiving a copy for our information. Candidate species are those species for which the Service has sufficient information to support a proposal for listing as threatened or endangered under the Act. Species of concern are those species whose conservation standing is of concern to the Service, but for which further status information is still needed. Conservation measures for species of concern and candidate speciesare voluntary, but recommended. Protection provided to these species now may preclude possible listing in the future. Please be advised that State regulations may also require permits in areas where wetlands are identified. You should contact the WasNngton State Department of Ecology for State permit requirements. There may be other Federally listed species that may occur in the vicinity of your project which are under the jurisdiction of the National Marine Fisheries Service (NMFS). Please contact NMFS at (503) 230-5400 to request a species list. Your interest in endangered species is appreciated. If you have additional questions regarding your responsibilities under the Act, please contact Chandra Madrona at (360) 753-7762 or John Grettenberger at (360) 763-6044 of this office. Sincerely, avid C. Frederick 4 Supervisor cnr/j kp Enclosures SE/COE/1-3-97-SP-395/Kiiig c. COE, Seattle WDFW, Region 4 WNHP, Olympia 2 ATTACHMENT A LISTED AND PROPOSED ENDANGERED AND THREATENED SPECIES, CANDIDATE SPECIES AND SPECIES OF CONCERN WHICH MAY OCCUR WITHIN THE VICINITY OF THE PROPOSED PORT QUENDALL DEVELOPMENT PROJECT ON LAKE WASHINGTON, SEATTLE, IN KING COUNTY, WASHINGTON (T24N R05E S29-32) FWS FXF: 1-3-97-SP-395 LISTED Bald eagle (Haliaeetus leucocephalus) - wintering bald eagles may occur in the vicinity of the project from about October 31 through March 31. There is one bald eagle nesting territory located in the vicinity of the project at T24N R05E S30. Nesting activities occur from about January l through August 15. Major concerns that should be addressed in your Biological Assessment of project impacts to bald eagles are: 1. Level of use of the project area by bald eagles. 2. Effect of the project on eagles' primary food stocks and foraging areas in all areas influenced by the project. 3. Impacts from project constniction and implementation (e.g., increased noise levels, increased human activity andlor access, loss or degradation of habitat) which may result in disturbance to eagles and/or their avoidance of the project area. PROPOSED None DESIGNATED None ATTACHMENT A (CONTINUED) CANDIDATES The following candidate species may occur in the vicinity of the project: Oregon spotted frog (Rana preliosa) SPECIES Or CONCERN The following species of concern may occur in the vicinity of the project: Long-eared myotis (Myolis evotis) Long-legged rnyotis (Myotis volans) Northwestern pond turtle (Clemmys marniorata marmorala) Olive -sided flycatcher (Contopus borealis) Pacific western big -eared bat (Corynorhinus (=Plecolus) townsendii townsendii) AITACHIIIENT B FEDERAL AGENCIES' RESPONSIBHXrIES UNDER SECTIONS 7(a) AND 7(Q OF THE ENDANGERED SPECIES ACT OF 1973, AS AMENDED Requires: 1. Federal agencies to utilize their authorities to carry out programs to conserve endangered and threatened species; 2. Consultation with FWS when a federal action may affect a listed endangered or threatened species to ensure that any action authorized, funded, or carried out by a federal agency is not likely to jeopardize the continued existence of listed species or result in the destruction or adverse modification of critical habitat. The process is initiated by the federal agency after it has determined if its action may affect (adversely or beneficially) a listed species; and 3. Conference with FWS when a federal action is likely to jeopardize the continued existence of.a proposed species or result in destruction or an adverse modification of proposed critical habitat. SECTION 7(ci - Biological Assessment for Construction Projects * Requires federal agencies or their designees to prepare a Biological Assessment (BA) for construction projects only. The purpose of the BA is to identify any proposed -and/or listed species which is/are likely to be affected by a construction project. The process is initiated by a federal agency in requesting a list of proposed and listed threatened and endangered species (fist attached): The BA should be completed within 180 days after its initiation (or within such, a time period as is mutually agreeable). If the BA is not initiated within 90 days of receipt of the species Iist, please verify the accuracy of the list with our Service. No irreversible commitment of resources is to be made during the BA process which would result in violation of the requirements under Section 7(a) of the Act. Planning, design, and administrative actions may be taken however, no construction may begin_ To complete the BA, your agency or its designee should: (1) conduct an onsite inspection of the area to be affected by the proposal, which may include a detailed survey of the area to determine if the species is present and whether suitable habitat exists for either expanding the existing population or potential reintroduction of the species; (2) review literature and scientific data to determine species distribution, habitat needs, and other biological requirements; (3) interview experts including those within the FWS, National Maxine Fisheries Service, state conservation department, universities, and others who may have data not yet published in scientific literature; (4) review and analyze the effects of the proposal on the species in terms of individuals and populations, including consideration of cumulative effects of the proposal on the species and its habitat; (S) analyze alternative actions that may provide conservation measures; and (6) prepare a report documenting the results, including a discussion of study methods used, any problems encountered, and other relevant information Upon completion the report should be forwarded to our Endangered Species Division, 3704 Griffin Lane SE, Suite 102, Olympia, WA 98501-2192. * "Construction project" means any major federal action which significantly affects tht; quality of the human environment (requiring an EIS), designed primarily to result in the building or erection of human -made structures such as dams, buildings, roads, pipefines, channels, and the like. This includes federal, action such as permits, grants, licenses, or other. forms of federal' authorization or approval which may result in construction. State of Washington DEPARTMENT OF FISH AND WILDLIFE M*]Hnq Address: 500 CapOd Way N, Olympia, WA SMI-1021 - (NO) 902.2200; TDO {3$0) 902.2201 Main O10oe Location: Natural Resources Bundlny, 11 t i Wssldnglnn Street SE, Olympia, WA Date: /Yl.._y /a, lV7 Dear Data Requester: Enclosed is the information you requested from the Washington Department of Fish and Wildlife (WDFW) concerning the agency's priority habitats and species. This package may also contain documentation to help you understand and use these data. This information only includes data that WDFW maintains in a centralized data system. It is not an attempt to provide you with an official agency response as to the impacts of your project on fish and wildlife. Nor is it designed to provide you with guidance on interpreting this information and determining how to proceed in consideration of fish and wildlife_ This data only documents the location of important fish and wildlife resources to the best of our knowledge. It is important to note that priority habitats or species may occur on the ground in areas not currently known to WDFW biologists, or in areas for which comprehensive surveys have not been conducted. Site -specific surveys are frequently necessary to rule out the presence of priority habitats or species. Your project may require further field inspection or you may need to contact our field biologists or others in WDFW to assist you in interpreting and applying these data. Refer to the enclosed directory and regional map for those contacts. Generally, for assistance on a specific project, you should contact the appropriate WDFW regional office and ask for the area habitat biologist for your project area. Please note that sections potentially impacted by spotted owl management concerns are displayed on the 1:24,000 scale standard map products. If specific details on spotted owl site centers are required they must be specially requested. WDFW periodically updates this information as additional data become available. Because fish and wildlife species are mobile and because priority habitats and species data is dynamic, project reviews for fish and wildlife should not rest solely on mapped information. Instead, they should also consider new data gathered from current Meld investigations. Remember, priority habitats and species data can only show that a species or habitat type is present, they cannot show that a species or habitat type is not present. These data should not be used for future projects. Please obtain regular (6 months) updates rather than use outdated information. Because of the high volume of requests for information that WDFW receives, we need to charge for these data to recover some of our costs. Enclosed is an invoice itemizing the costs for your data and instructions for submitting payment. WDFW ADMINISTRATIVE REGIONS AND LIST OF REGIONAL HABITAT PROGRAM MANAGERS o w N ` o A o and t ats.pll Okknoaan 1i.r7'y et_w.nu RE ION 1 am .ri111Crook Cla.tin GION 4 xinr Harter !Gill lF.as Pi.rw 7'hv Ma L, Cowl" • Yakh" _REGION 5 Yw3dr uae,.til. REGION 3 Clark REGION 1 John Andrews 8702 North DiAsion Street Spokane, Washington 99218-1199 Phone: (509) 456-4082 REGION 2 Tracy Lloyd 1550 Alder Street N.W. Ephrata, Washington 98823-9652 Phone: (509) 754-4624 (REGION 3 Ted Clausing 1701 South 24th Avenue Yaldma, Washington 98902-5720 Phone: (509) 575-2740 Janlary 1997 KII-kitat a n 1a a O N Dov.tl.a I I Llnawn . Ephrata oe_"k R GION 2 Aaanrt. Tr.nkiLn B.nton 1 Ma1La Maus REGION 4 i a Spokane Jlpelun. x f0 lfriitmsn Ted Muller 16018 Mill Creek Boulevard Mill Creek, Washington 98012-1296 Phone: (206)"775-1311 REGION 5 Bryan Cowan 5405 N.E. Hazel Dell Avenue Vancouver, Washington 98663-1299 Phone: (360) 696-6211 REGION 6 Dave Gufler 48 Devonshire Road Montesano, Washington 98563-9618 Phone: (360) 249-6523 TRLAD Bubee Miff ASSOCIATES 11814 115th Avenue NE Kirkland, WA 98014-6923 425.821.9448 42S 821.3481 fax 800.488.0756 tall free 13roNq wv✓vv. ViadassoC-CURT City of Renton, Washington Preliminary Storm Drainage Report Prepared By: Barnaby D. Hoit Reviewed By: Clay A. Loomis, P.E. July 10, 2000 Triad Job No. 00- 153 City of Renton, Washington Preliminary Storm Drainage Report Prepared By: Barnaby D. Hoit Reviewed By: Clay A. Loomis, P.E. 'dam TRIAD ASSOCIATES July 10, 2000 Triad Job No. 00- 153 Barbee Mill Property Preliminary Technical Information Report TABLE OF CONTENTS SECTION I PROJECT OVERVIEW ....................................................................................................1-1 SECTION II CONDITIONS & REQUIREMENTS SUMMARY.......................................................11-1 SECTION III OFFSITE ANALYSIS....................................................................... .........................1I1-1 SECTION IV FLOW CONTROL & WATER QUALITY FACILITY ANALYSIS & DESIGN ...IV-1 FLOWCONTROL ............................................ ............. ......................................................................... - IV-] WATERQUALITY ........................................... .... ...................... ...................................... I ...... ........ ......... IV-] SECTION V CONVEYANCE SYSTEM ANALYSIS & DESIGN......................................................V-1 SECTION VI SPECIAL REPORTS & STUDIES............................................................................... VI-1 SECTION VII OTHER PERMITS..................................................................................................... VII-I SECTION VIII ESC ANALYSIS & DESIGN................................................................................... VIII-1 SECTION IX BOND QUANTITIES, FACILITY SUMMARIES, & DECLARATION OF COVENANT.......................................................................................................................................I.... IX-1 SECTION X OPERATIONS & MAINTENANCE MANUAL ....... ...................................................... X-1 7111/00 Triad Associates Job 400-153 Page i Barbee Mill Property Preliminary Technical Information Report SUPPLEMENTAL INFORMATION Supplemental information noted as included is found at the end of each respective section as listed here. SECTION I PROJECT OVERVIEW King County Soil Map, Sheet No. 5 SECTION II CONDITIONS & REQUIREMENTS SUMMARY SECTION III OFFSITE ANALYSIS FIRM Panel 664 (May Creek Floodplain) King County Sensitive Areas Portfolio -Streams and 100-yr Floodplains (Sheet 4) King County Sensitive Areas Portfolio -Wetlands (Sheet 4) SECTION IV FLOW CONTROL & WATER QUALITY FACILITY ANALYSIS & DESIGN Stormwater Management Stormfilter System information. King County 2-, 10-, 25- and 100-year 24-hour Isopluvials. SECTION V CONVEYANCE SYSTEM ANALYSIS & DESIGN SECTION VI SPECIAL REPORTS & STUDIES Wetland Determination Report on the Jag Development Property_ David Evans and Associates, Inc. Revised May 1997 SECTION VII OTHER PERMITS SECTION VIII ESC ANALYSIS & DESIGN SECTION IX BOND QUANTITIES, FACILITY SUMMARIES, & DECLARATION OF COVENANT SECTION X OPERATIONS & MAINTENANCE MANUAL EXHIBIT POCKETS 7/11 /00 Triad Associates Job #00-153 Page ii Barbee Mill Property Preliminary Technical Information Report Section I PROJECT OVERVIEW The project proposes to construct a high -density, mixed -use development at the site of the existing Barbee Mill on the East Shore of Lake Washington in North Renton. The site's street address is 4300 Lake Washington Boulevard and it is located in the Northwest % Section 32 and Southwest 114 Section 29, Township 24 North, Range 5 East, W.M. The roughly triangular shaped site is bound by Lake Washington on the west and by the Burlington Northern Railroad Tracks to the Southeast. See the Vicinity Map below for the site location. r, �4 y 2� Site NE Newcastle Oth St 38th - z 0 NE 30th S Creek � Lake PP Washington p v 4 �� Renton � v w NE 12th S VICINITY MAP (Not to Scale) The site is approximately 22.91 acres, including some submerged land and land leased from the Department of Natural Resources. The proposed development area is approximately 20.57 acres, which excludes the sensitive areas (May Creek), exemptions from the project (an existing private boat house and launch at the southern end of the site) and submerged land. Historically, the site has been used for large-scale commercial milling, curing and storing of lumber. Mill production is currently limited to small custom cuts, and much of the site is idle and urunaintained. The existing site is industrial with approximately 15 milling, storage and kiln buildings and an extensive asphalt 7111/00 Triad Associates Job #00-153 Page I -I Barbee Mill Property Preliminary Technical Information Report yard. Please see the Existing Conditions Exhibit in the exhibit pockets. The existing site has approximately 17 acres of impervious coverage (=74%). The proposed mixed -use development will provide extensive landscaping and open space (including a waterfront park) and will reduce the total impervious coverage to approximately 10.5 acres (_-460/6). The site soils are mapped as Norma Sandy Loam (see King County Soil Map, Sheet No. 5, included). The proposed development includes restaurants, retail space, offices, condominiums and a hotel. The project proposes to demolish the existing buildings except for the mill (Building I), which will be remodeled as a restaurant (and some retail space). Please see the Conceptual Site Plan Exhibit in the Appendix for the proposed project layout. The proposed site plan would achieve approximately 200,000 sf of commercial space, 1,976 parking stalls and 617 dwelling units among seven buildings. The existing site runoff appears to sheet flow directly to Lake Washington. The proposed site runoff will be collected in catch basins, yard drains and roof drains, and then routed in tightline drainage systems to modular cartridge filter systems which provide water quality treatment. The treated filter effluent will be discharged to Lake Washington. Because the site has little relief (typical slopes of 0-2%), the developed site will have several drainage systems, dividing the site in to several smaller sub -basins. This will allow drainage to be collected with minimum fall across the site. 7/11100 Triad Associates .lob #00-153 Page 1-2 Kennydale Coleman Poin V SHEET NO. 5 ` ' :AgC i r KING COUNTY AREA, WASHINGTON' (MERCER ISLAND QUADRANGLE AND - PART OF SEAWLE SOUTH QUADRANGLE} a a l r ;f }}A.c ' r f g t" o-- B �i � � ��e• ; BWI Plea, urn t ,� i lir Arne, az Inc AkF Bh BN 3 qgC r 42 F� yBeCr g v � f Aga •Pin WPfl ur Hilfs inA 1 ii ABC ---- + • .w AmC 0� EBB h Kph BeC C k r 2 Agp< - 'BM � 396 • EvC BeD AgC J AmC ! Bh Bh • _~•EvC 9 AgC ay e KpC P �- - B 1= Agfl B1 rE 64 \ ■ yak i AgC 1' ` f . AgC BVI �. •�' Sm � AgC •! �, � . AgC 13 r._ F AgD AgD ; 0 + . tt� AgD p SRC • /. 'III, � I' •!nG AkF I .. o- AkF AgC EvB ` ! BeG 'r py GAA VEL j PrT � '• AkF JInA its WVs 04 n�BM I1 i My ? 0M- 01 9 1 A Evc/,f� n n�VD AgC • 'i ' u AkF ar ! — AmC MIR - J M EvC _t, I Agp° k Barbee Mill Property Preliminary Technical Information Report Section II CONDITIONS & REQUIREMENTS SUMMARY No conditions or requirements have been established the City at this preliminary application stage. 7111100 Triad Associates Job 900-153 Page H-1 Barbee Mill Property Preliminary Technical Information Report Section III OFFSITE ANALYSIS The site has no significant offsite drainage issues. The project is on the shores of Lake Washington. May Creek flows through the site near its southeast boundary and the creek mouth is the southern end of the site. The existing railroad tracks intercept any significant upstream drainage. Please see the Existing Conditions Exhibit in the Exhibit Pockets. May Creek appears to be in good condition adjacent to the project and flows in a well -defied channel. The Flood Insurance Rate Map (FIRM) for the site area (Panel 664, included) shows that the detailed study area ends just within the eastern boundary of the site. The floodplain depicted on the FIRM appears well contained within the banks. The creek floodplain was not modeled for most of the site because of the proximity to Lake Washington, The final flood elevation listed (for Section A) is 21 feet (NVGD 1929). The Ordinary High Water Mark (OHWM) elevation for Lake Washington is 15.13 feet (NGVD 1929) (this is a conservative elevation, corresponding to overflow at the locks). The finished grades of the site will be set sufficiently above the OHWM to prevent flooding and to allow for conveyance of site flows. The proposed creek crossings' designs will not obstruct the creek. The project proposes to improve the stream corridor by creating 50-foot vegetated buffers along the stream corridor. The buffer will be planted with native species to enhance the creek habitat and to improve the bank stability. 7/11/00 Triad Associates ,lob #00-153 Page III -I I To determine if flood insurance is available, contact an insurance agent or call the National Flood Insurance Program at (800) 638-6620. 4 ' I APPROXIMATE SCALE IN FEET E 500 0 500 1 NATIONAL ROOD INSURANCE PROGRAM 1 �Illlllll�q FooRuINSURANCE RATE MAP KING COUNTY, WASHINGTON AND INCORPORATED AREAS I PANEL 664 OF 1725 (SEE MAP INDEX FOR PANELS NOT PRINTED) I CONTAINS: COMMUNITY KING COUNTY, - UNINCORPORATED AREAS RENTON, CITY OF NUMBER PANEL SUFFIX 530071 066A F 5300W 06" F MAP NUMBER 53033CO664 F MAP REVISED: MAY 16,1995 %orderal Emergency Management Agency LEGEND SPECIAL FLOOD HAZARD AREAS INUNDATED BY 100—YEAR FLOOD ZONE A No base flood elevations determined. IONE AE Base flood elevations determined. ZONE AH Flood depths of t to 3 feet rusually areas of pondingl; base flood etevatiom determined_ ZONE AO Flood depths of 1 to 3 feet [usually sheet flow on sloping lerrainl; average depths determined. For areas of alluvial fan flooding, velocities also determined. ZONE A99 To be protected from tDG-year flood by Federal flood protection system under construction; no base elevations determined. ZONE V Coastal flood with velocity hazard Iwave action]; no base flood elevations determined. ZONE VE Coastal flood with velocity hazard {wave action); base flood elevations determined. FLOODWAY AREAS IN ZONE AE OTHER FLOOD AREAS r� ZONE % Areas of 500 year flood; areas of 146 year flood with average depths of less than 1 font or with drainage areas less than 1 square mile; and areas protected by levees from 100-..year flood. OTHER AREAS ZONE X Areas determined to be outside 500-year ffoociplain. ZONE O Areas in which flood hazards are undetermined. UNDEVELOPED COASTAL BARRIERS Identified Identified Otherwise 1983 1990 Protected Areas Coastal barrier areas are normally located within or adjacent to Special Flood Hazard Areas. Flood Boundary Floodway Boundary Zone D Boundary Boundary Dividing Special Flood Hazard Zones. and Boundary Dividing Areas of Different Coastal Base Flood Elevations Within Special Flood Hazard Zones. base Flood Elevation Line: - 513- Elevation in Feet. See Map Index for Elevation Datum. D D Goss Section Line Base Flood Elevation in . Feet (EL 987) Where Uniform Within Zone. See Map Index for Elevation Datum. RM7 X Elevation Reference Mark M2 River Mile Horizontal Coordinates Based on North 97007'30". 32°22'30" American Datum of 1927 (NAD 27) Projection. NOTES This map is for use in administering the National Flood Insurance Program: it does not necessarily identify all areas subject to flooding, particularly from focal drainage sources of small size, or all planimetric features outside Special Flood Hazard Areas. Coastal base flood elevations apply only landward of 0.0 NGVD, and 'include the effects of wave action; these elevations may also differ significantly from those developed by the National Weather Service for hurricane evacuation planning_ A,—, —F c.,o,.�„I Rnr.A w9�9.n nrra_,.os. 41—, 1 inn1„r10 7nnvc 8 AF AH Ar) c r JOINS PANEL 0675 ZONE X SITE \. a 0 w \ LIMIT OF z DETAILED STUDY N� w 0 z O T. Q _ z 9 May Creek ZONE AE ZON NX m G RM210 ZONE X so L N 40TH STREET dQ y cc o a � z F MEADOW o tNti NORTH J O w 47 / NORTH 38TH STREET z 7) z w w Q w z r z NORTH 37TH STREET j 52 z NORTH 37TH STREET Q z w K � � w � c� w u Q NORTH 36TH STREET NE 36TH ST Q NORTH 36TH STREET �'1 32 z z KING COUN NORTH 35TH STREET a UNINCORFORATEI 530071 a Q 6a r* NORTH 34TH STREET d) � z c May m NORTH 33RD PLACE C7'Ep,�t 72 ZONE X O CITY OF NORTH 33RD STREET ZONE X 531 M M NORTH 32ND STREET 1 ORTH 32ND STREET 77 ZONE X w 4 Z w VORTH a 31ST STREET RM21 ZONE A X co ZONE X g2 10RTH 30TH STREET NORTHEAST 30TH STREET Rt C4 1. 10, 1.4 J's A ij 4, I.E r -,q C) 1, mz 15 -4:, w, .5-- ul 42 -"k W W �k' 4rI- , ;K'4 _ 1( i'. ITT �ii' r, i` a am nil' 1A Nj +lj L) kl C14 'w 444-4 . 4 —tK ri S 4 W, p LOL vlv i5 H zi C) LI r, TV 43 o ci F m-T I .IJ C-1 Barbee Mill Property Preliminary Technical Information Report Section IV FLOW CONTROL & WATER DUALITY FACILITY ANALYSIS & DESIGN The proposed Stormwater systems will be designed to meet the City of Renton standards. Renton has adopted the King County Surface Water Design Manual (KCS)ArDM) with some modifications. The preliminary design shown on the Preliminary Stormwater Plan (included in the Site Plan Approval Application plan set submitted concurrently with this report) is intended to meet these requirements (at the conceptual level of detail). Flow Control The current KCSWDM, September 1998, lists Lake Washington as a Major Receiving Water (page 1-29, Table 1.2.3.13). The KCSWDM includes exemptions from the Flow Control requirement (Core Requirement 3). Exemption 6, Direct Discharge Exemption, applies to sites draining to Major Receiving Waters. 1f these sites meet the exemption requirements (a-b on pages 1-28 and 1-29), flow control (detention/retention) is not required. The project site will meet these requirements by providing tightlined conveyances to the lake and engineered outfalls. The development will not impact any stormwater conveyances_ Wafer Quality Core Requirement 8, Water Quality, requires'water quality treatment for runoff from pollution generating surfaces (traffic areas, etc). As shown on the Preliminary Stormwater Plan, a modular cartridge filter system is proposed for site stormwater quality treatment. Specifically, the proposed water quality facilities are the Leaf Compost Filters (LCF) by Stormwater Management. Use of these systems is covered under KCSWDM Section 6.5.5, Leaf Compost Filters (LCF). Design information from Stormwater Management is included at the end of this section. A leaf compost filter removes pollutants through filtration, ion exchange, adsorption, and microbial degradation. Stormwater Management's modular cartridge system can contain other media besides the leaf compost pellets, which can be specified depending on site characteristics and treatment goals. 7/11/00 Triad Associates Job 400-153 Page IV -I SEC11ON 3.2 RUNOFF COMPUTATION AND ANALYSIS METHODS FIGURE 31.1.A 2-YEAR 24-HOUR ISOPLUVIALS amotlom"_HT "TY _ _ _ G KINCOUMTT 4 TSS tv 2. �{C� a'f i' �e4cst+re � a�•e w.y y ref - � � •- . '�, Fqt; . �♦ 1. .A f { , �, Zip• E ^. M-�I y PiEPCG�Cpp NTY � '.4x WESTERN h4' KING COUNTYIV 2-Year 24-Hours, Precipitation•ry <0 ry in Inches °�-�� Mites 9/1198 1998 Surface Water Design Manual 3-14 3.2.1 RA71ONAL METHOD IFIGURE 3.2.1.B 10-YEAR 24-HOUR ISOPLUVIALS I j� 'Al 4.0 w ......... ......... Qk_ :IV N1 qD JW -ING coo. * t WESTERN KING COUNTY IVq0 4.5 1 0-Year 24-Hour 4.0 Precipitation 0 2 4 Miles in Inches 1998 Surface Water Design Manual 911/99 3-15 SECTION 3.2 RUNOFF COMPUTATION AND ANALYSIS N1E lODS FIGURE 3.2.1.0 25-YEAR 24-HOUR ISOPLUViALS ., r i a F C i N.11 (� its '•i'-^ 1 , ... �''" k 3 yl '..4 % 6 £ f (1 v Ko-c COUNTY �J• PIEACE COUNTY 0 WESTERN KING COUNTY ` - S$ N ` "�•0 25-Year 24-Hours 4' u Precipitation lb in Inches °+ Wes05 � 911198 1998 Surface Water Design Manual 3-16 3.2.1 RATIONAL METHOD FIGURE 3.2.1.D 100-YEAR 24-HOUR ISOPLUYIALS .-_ - .�� .., — --- --- -94 COUNTY p91 1 p 3 R Wr+ i f R .s E;v C _._ M+�..® 0 PIE CC t.0 i1NiT WESTERN 6.5 KING COUNTY o�• 6.0 _mil 5.5 100-Year 24-Hour �`• �,'�.� - Precipitation In Inches �� Miles �o 911/98 1998 Surface Water Design Manual. 3-17 6 A. Introduction 1. Filter Media 2. Pollutant Removal 3. System Hydraulics Figure 1. Precast Concrete Vault Figure 2. Filter Cartridge B. Design Constants STORMWATER 0 STORMWATER MANAGEMENT MANAGEMENT updated 4/99 INTRODUCTION Stormwater Management develops innovative stormwater treatment solutions for engineers, developers.and jurisdictional authorities to help keep our waterways clean. Since 1991, Stormwater Management's patented signature product — called StormFilterTl — has been treating stormwater runoff from small single retail sites to large urban parking lots, residential streets, urban roadways and freeways. The StormFilter uses filter cartridges housed in standard size pre -cast concrete vaults or cast in place vaults to produce a self-contained stormwater filtering system. The filter systems are installed in -line with storm drains. The system works by percolating stormwater through the filter cartridges containing filter media- The filter media traps particulates and adsorbs materials such as dissolved metals and hydrocarbons. Surface scums, floating oil and grease are also removed. After passing through the filter media, the stormwater flows into a collection pipe or discharges to an open channel drainage way. The StormFilter is designed to be very effective for the treatment of first flush flows, particularly those storms early in the rainy season. In general, the StormFilter's efficiency is highest when pollutant concentrations are highest_ Am 1111011 FILTER MEDIA The StormFilter utilizes a variety of media to target and remove pollutants from stormwater runoff. It is the first and only stormwater treatment system to offer such a versatile approach to removing site -specific pollutants. We can 'customize' the StormFilter by using different filter media to remove desired levels of sediments, soluble phosphorus, nitrates, soluble metals, and oil and grease_ In many cases, we recommend using a combination of media to effectively remove stormwater pollutants. Technical memoranda detailing removal efficiencies for the media are available from our Research and Development department. CSF(D Leaf Media Using a feed stock of pure deciduous leaves (i.e_ no mixed yard debris such as prunings and grass) Stormwater Management composts leaves collected by the City of Portland, Oregon, over a period of eight months into a mature stable compost. Stormwater Management then processes the finished compost into an organic granular media, which resembles granular soil and has no odors. Once complete, the media has physical and chemical characteristics desirable for the filtration of stormwater. There are three primary pollutant removal mechanisms performed by the CSF'�o media. These mechanisms are: mechanical filtration to remove sediments and associated total Phosphorus, chemical processes to remove soluble metals, and adsorption properties to remove oils and greases. ID STORMWATER MANAGEMENT updated 4199 1 Suspended Solids: The StormFiiter is comprised of a series of filter cartridges, each with a seven inch thick layer of the media through which stormwater passes. Sediments are filtered out on both the surface of the cartridge and the surfaces of granules throughout the media matrix_ As sediments are removed from stormwater runoff and accumulate on the surface of the filter, the permeability will decline thus requiring facility maintenance. Sediment removal will vary with particle size distribution and influent concentration, but removal has been as high as 95%. Heavy Metals: The CSF@ media also acts as a chemical filter to remove dissolved ionic pollutants such as heavy metals, including lead, copper, and zinc. The mechanism of cation exchange is provided by humic substances, which are a product of the aerobic biological activity during the composting process. Heavy metal removal rates vary from 65% to 95%. Oil & Grease: Removal of ail and grease (O&G) as well as some other organic compounds is facilitated by the high organic carbon content of the CSF® media. The system performs best when O&G loadings are less than 25 mg/l. Measured removal rates are as high as 85%. Detailed performance data are available upon request. Removal of other pollutants such as chlorinated hydrocarbons has been demonstrated_ However, in the case of specific target pollutants we recommend having a characterization study performed in our laboratory. Perlite Perlite is a naturally -occurring `puffed' volcanic ash. This lightweight material is commonly used as a water filtration media_ Although perlite is not chemically active, its highly porous nature, multicellular structure, and rough edges make it very effective for removal of fine particles. Perlite can be used as a standalone media or in conjunction with the pleated fabric insert and/or other available media. The primary pollutants targeted by Perlite are: Suspended solids: Perlite, with its many pores and rough edges, is an ideal media for trapping suspended solids. Laboratory and field testing have demonstrated that perlite is able to capture even fine silt and clay particles while maintaining a robust resistance to clogging by heavy sediment loads. Oil and grease: The perlite's extreme porosity and high surface area allow it to act like a sponge and physically capture free oils and greases as these pollutants flow across its surface. Independent studies have shown 80% removal of oil and grease at low concentrations typically associated with parking lot and roadway runoff. Zeol ite Zeolites are naturally -occurring minerals that have been used in a variety of applications to filter water. Stormwater Management uses a zeolite that has been demonstrated to be useful for removal of anions, as well as cations, from stormwater runoff. The zeolite can be used as a standalone media or combined with other media to target and remove site -specific pollutants. 0 STORMWATER MANAGEMENT updated 4/99 T3 Suspended Solids: The granular nature of the zeolite allows for removal of suspended solids as the stormwater percolates through the macro pores of the media. Microscopic channels within the individual zeolite granules also aid in the removal of silt and clay particles. Heavy Metals: Removal of soluble heavy metals, such as lead, copper and zinc ions, is facilitated by the cation exchange capacity (CEC) of the zeolite. With a GEC of about 60 meq/100 grams, the zeolite will release light cations, such as calcium and magnesium, and attach heavy metal ions such as lead, copper and zinc. The heavy metals are then bound to these sites and are not re-released into the stormwater at a later time. Nutrients: Stormwater Management now offers a modified zeolite that has the ability to remove anionic pollutants such as nitrates and ortho (soluble) phosphorus. The individual zeolite granules have been modified to reverse the surface charge (from negative charge to a positive charge), which electrostatically attracts negatively -charged ions. For ortho phosphorus, the maximum adsorption capacity is about 140 mg/kg. Pleated Fabric Inserts Stormwater Management's pleated fabric inserts are designed to be used as a standalone media or in conjunction with other types of media for more effective pollutant removal. The pleated fabric insert is used primarily for sediment (TSS) control. The insert fits inside the standard cartridge, leaving an annular space between the inside of the insert and the drainage tube. This space can be used for the addition of granular media to remove selected soluble pollutants_ For example, if TSS and soluble phosphorus are pollutants of concern, we may recommend combining the pleated fabric insert with the zeolite media. The pleated fabric inserts are constructed of durable polyester fabrics. They can be removed, washed with a hose and placed back into the filter cartridge. The inserts are designed to be reused many times. Other Media The StormFilter provides a high level of versatility and has been used with other media, such as granulated activated charcoal (GAC). Systems may also be placed in series. For example, the cartridges in the first system use Perlite to address the bulk solids loading, and the second system would use GAC to address soluble organics. Stormwater Management is continuously evaluating different types of media to remove very specific pollutants. If you have an "unusual" pollutant that needs to be removed, ask our applications engineers. SYSTEM HYDRAULICS The StormFilter is sized to treat the peak flow of a water quality design storm as it passes through the system. The peak flow is determined by calculations based on the contributing watershed hydrology and using a design storm magnitude. The design storm is usually based on the requirements set by the local regulatory agency. The particular size of a StormFilter is determined by the number of filter cartridges required to treat the peak water quality flow- © STORMWATER MANAGEMENT updated 4199 6 I Flow Spreader Inlet ` Precast Storm iFi fter Underdrnin Mzsnifold Figure 1 Energy Dissipater Ac.cema Doors Mounted Into 7rafTio-banning Lid --.. t Putlet The typical unit configuration in Figure 1 consists of an inlet bay, baffle, cartridge bay, an overflow baffle, and outlet bay. The inlet bay serves as a grit chamber and provides for flow transition into the cartridge bay. The flow spreader provides for the trapping of floatables, oils, and surface scum. Water enters the cartridge bay through the flow spreader and begins to pond. As shown in Figure 2, the water ponds, infiltrates through the media into the inner drainage tube and begins to raise the float_ Once the pending submerges the cartridges, the float will pull loose and generate a siphon effect which greatly increases the flow potential across the filter media. © STORMWATER MANAGEMENT updated 4199 AIR VENT �\ AIR REIJEF VANE SCP.E-Y GRAT UR MEDIA / FLOAT OUTEr SCRE&I rjPnOWL PLF,. TEO FA$F.IC INSEFT —' FLOOR PALL VAU.,'E a Figure 2. UNDEPOPMI'l MANIFOLD HOOD CENTER GP.AINAGEE TIJEE The siphon effect will continue until the water is drawn down to the lower lip of the hood at which time air is entrained and the siphon is lost. Water will continue to drain gravitationally until the ball reseats its0f and resets the system. Each cartridge is designed to treat a peak flow of 15 gpm (30 cartridgeslcfs). For example: a peak design stormwater flow rate of 150 gpm would require that 10 cartridges be used in the treatment vault. The cartridges connect into a pipe manifold that is cast into the floor of the vault. The StormFilter typically requires 2.3 feet of head differential between the invert of the inlet and the invert of the outlet. Because of the highly porous nature of the various media, the flow through a newly installed cartridge is restricted to 15 gpm using a flow control orifice located at the outlet of each manifold pipe. The orifice controls the flow from three to eight cartridges (i.e. 45 to 120 gpm). It is calibrated and adjusted such that, at design head, the maximum flow is throttled to the number of cartridges on line times 15 gpm per cartridge. The StormFilter is also designed with an inline overflow. The overflow operates when the inflow rate is greater than the infiltration capacity of the filter media. Depending on site characteristics, some systems are equipped with high and/or low flow bypasses. High flow bypasses are installed when the calculated peak storm evert generates a flow that overcomes the overflow capacity or design capacity of the system. This is important for the pre -cast systems. Base flow bypasses are sometimes installed to prevent continuous inflows caused by groundwater seepage, which usually does not require treatment. For more information, refer to the System Design section. 0 STORMWATER MANAGEMENT updated 4/99 J Barbee Mill Property Preliminary Technical Information Report Section V CONVEYANCE SYSTEM ANALYSIS & DESIGN A conceptual drainage plan design is shown the Preliminary Stormwater Plan. The drainage system will be analyzed with a backwater model and the pipes sized during the detailed engineering design. Note that all the pollution generating surfaces will be routed through filtration systems prior to being discharged to Lake Washington. Multiple drainage systems are proposed to minimize the required fall across the site. 7/11/00 Triad Associates Job #00-153 Page V-1 Barbee Mill Property Preliminary Technical Information Report Section VI SPECIAL REPORTS & STUDIES David Evans and Associates have previously prepared a wetland report, Wetland Determination Report on the Jag Development Property (revised May 1997), which is included in the Level II Site Plan Application. The report addresses five adjacent parcels of land, including the Barbee Mill site. One 6,151 sf category 3 wetland is identified adjacent to the Barbee Mill property (identified as Wetland H in the report). The wetland is located between the site and the adjacent Burlington Railroad Tracks. The approximate wetland location and required 25-foot buffer is shown on Conceptual Site Plan Exhibit (in the Exhibit Pockets). 7/11/00 Triad Associates Job #00-153 Page VI -I Barbee Mill Property Preliminary Technical Information Report Section VII OTHER PERMITS It is anticipated that multiply permits will be required for this site and will be applied as the design process continues. Permits that are expected to be required are-- * Level I Site Plan Approval from the City of Renton * Level II Site Plan Approval from the City of Renton * SEPA Threshold Determination from the City of Renton * Shoreline Substantial Development Permit from the City of Renton * Clearing and Grading Permits from the City of Renton * Building Permits from the City of Renton * Nationwide Permits (for marina) from the Army Corps of Engineer HPA from the Dept_ of Fish & Wildlife 7/11/00 Triad Associates Job #00-153 Page VII-1 Barbee Mill Property Preliminary Technical Information Report Section VIII ESC ANALYSIS & DESIGN All sites are required to provide Erosion and Sedimentation Control (ESC) measures to prevent erosion and transport of onsite soils to downstream drainage courses, facilities and property due to development (KCSWDM Core Requirement 5), This includes temporary measures implemented during construction and permanent measures to prevent erosion from the finished, developed site. A variety of Best Management Practices (BMPs) will be implemented on the detailed engineering plans. These BMPs will include surface stabilization (e.g. temporary and permanent planting, mulching and other cover methods as needed), perimeter protection (e_g_ silt fences), traffic area stabilization (e.g. construction entrance), sediment retention (e.g_ sediment ponds/traps), and surface water control (e.g. interceptor dikes and swales)_ ESC measures will be particularly important on this site due to the proximity to Lake Washington. The finished site should have a much lower sediment Ioading to Lake Washington due to the increased quality landscaping (with native species) and the addition of filtration systems (as described in the Section IV). 7/11/00 Triad Associates Job 900-153 Page VIII-1 Barbee Mill Property Preliminary Technical Information Report Section IX BOND QUANTITIES, FACILITY SUMMARIES, & DECLARATION OF COVENANT If required, bond quantities, facility summaries and declaration of covenant will be provided with the detailed engineering design or final plans, as required. 7/11/00 Triad Associates Job #00-153 Page IX -I Barbee Mill Property Preliminary Technical Information Report Section X OPERATIONS & MAINTENANCE MANUAL The operations and maintenance manual will be provided with the detailed engineering plans. 7/1 1/00 Triad Associates Job #00-153 Page X-1 Barbee Mill Property Preliminary Technical Information Report Exhibit Pockets LL44 01-173tK� Golder Associates Inc. 18300 NE Union HIII Road, Sulte 200 Redmond. WA 98052-3333 Telephone (425) 883-0777 Fax (425) 882-5498 REPORT TO BARBEE MILL COMPANY ON GEOTECHNICAL FEASIBILITY BARBEE MILL SITE DEVELOPMENT Prepared for: Barbee Mill Company P.O_ Box 359 Renton, WA 98057 Submitted by: Golder Associates Inc. Seattle, Washington (1914 j d4�� es G. johDfon Associate Engineering Geologist August 9, 2000 Reissued without changes; December 18, 2001 _. A ® 1 M DEVEt.OPMgN7 PLANNINGCITY Or PENNON DEC 1 1 2C 1 RECENED .$ - S W. Lo O.T.WAS', C q r ,y IEXPMEs 5/7.?/V3 I Charles W. Lockhart Principal OFFICES ACROSS ASIA, AUSiRALASIA, EUROPE, NORTH AMERICA, SOUTH AMERICA 003-1228 August 9, 2000 i 003-1228 TABLE OF CONTENTS Page No. 1. INTRODUCTION 1 1.1 Site Description 1 1.2 Project Description 1 2. PREVIOUS INVESTIGATIONS 2 3. SITE GEOLOGY 3 4. SUBSURFACE CONDITIONS 4 4.1 Soils 4 4.2 Groundwater 4 5. PRELIMINARY GEOTECHNICAL RECOMMENDATIONS 5 5.1 Preliminary Foundation Design 5 5.1.1 Building Support 5 5.1.2 Floor Slabs Support 5 5.2 Seismic Design 5 5.11 Liquefaction 5 5.2.2 Preliminary Seismic Design Criteria 6 5.3 Site Preparation 6 6. USE OF THIS REPORT 7 LIST OF FIGURES Figure 1 Vicinity Map Figure 2 Site Plan APPENDICES Appendix 1 Logs of Boreholes Golder Associates August 9, 2000 l 003-1228 1. INTRODUCTION Golder Associates Inc. (Golder) is pleased to present this report presenting feasibility - level geotechnical engineering recommendations for the Barbee Mill property located at 4101 Lake Washington Boulevard in Renton, Washington. Our scope of work included a review of the previous geotechnical investigations, feasibility- level engineering analysis, and the preparation of a geotechnical report. The report addresses the general guidelines required by the City of Renton for a geotechnical report. 1.1 Site Description The project site is located along the east shore of Lake Washington where May Creek empties into the lake, as indicated on Figure 1. The property is just under 23 acres in size and is wedge shaped. A set of railroad tracks and Lake Washington Boulevard run along the east property line, and vacant land borders the site to the north. The site topography slopes generally westward, from a high of about elevation 35 feet in the southeast to about elevation 20 to 21 feet along the lakefront. May Creek flows through the southeast portion of the site. The property is currently occupied by the Barbee Mill, a sawmill providing specialty cut wood. The mill property contains a bridge across May Creek along the main entrance road. There are about fifteen buildings on site and most of the area around the buildings is covered with asphalt paving. Log containment booms are located offshore. The mill is currently operational. 1.2 Project Description The proposed development concepts for the Barbee site include a combination of office, hoteVrestaurant and residential structures, with associated parking structures as well as at -grade parking. The building structures will be as high as seven (7) stories above grade. We understand that no below -grade construction is currently planned. Roadways will be constructed to access the buildings and parking areas, and landscaping will be introduced to complement the site development. A marina facility will be developed along the lakefront. Relatively minor site grading will be required to accommodate the site development. Generally, cuts and fills are less than five (5) feet in thickness. Golder Associates August 9, 2000 2 003-1228 2. PREVIOUS INVESTIGATIONS In preparing this report, we were provided with portions of a previous geotechnical report for the site vicinity prepared by Shannon and Wilson, Inc., dated February 1997, and boring loges from an environmental investigation carried out by Hart-Crowser, Inc. dated 9/98. A set of preliminary civil drawings of the proposed project development, prepared by Triad Associates, was also provided to assist in our understanding of the project development concepts. The most pertinent geotechnical data were the geotechnical borehole logs of two borings drilled on the Barbee site to a depth of 111 feet below ground surface and included in the Shannon and Wilson report. In addition, the text of their report referenced conditions on the adjacent properties to the north. The five (5) Hart-Crowser borings were shallow, ranging from a depth of about 9 to 21 feet. The locations of the borings drilled by the Shannon and Wilson and Hart Crowser are indicated on Figure 2 of this report. Copies of the logs of the borings are included in Appendix 1 of this report. Golder Associates August 9, 2000 3 003-1228 3. SITE GEOLOGY The Barbee site is located geologically in what is referred to as the Puget Sound lowland, which is a north -trending structural and topographic trough that extends from British Columbia to central western Washington. In general, the soil materials in this geologic feature are predominantly glacial materials deposited during several intercontinental glaciations in the region. Other significant geologic features in the near vicinity of the Barbee site, as reported in the Shannon and Wilson report, include the Mercer Island sunken forest and a splay of the Seattle Fault. The sunken forest is a large intact block of soil that reportedly slid from the upland of Mercer Island about 1,100 years ago during a strong earthquake. The mapped outline of this submerged soil mass extends about!/4 to %2 of the distance across Lake Washington between Mercer Island and the May Creek delta. The report also indicates that a southern splay of the Seattle Fault crosses in an east- northeast orientation less than a mile to the north of the center of the Barbee site. However, the report indicates that the closest formation that is cut by this fault is a tertiary rock outcrop of the Tukwila Formation, about three miles to the northeast, and that no Pleistocene or Holocene beds are known to be interrupted by this fault. Specific to the vicinity of the Barbee Mill site, the May Creek delta is the source of significant post -glacial sediment deposition. The creek is currently located on the south side of the delta, but has likely meandered across the breadth of the delta in the geologic past, depositing much of the near -surface soil materials which currently underlie the site. Golder Associates August 9, 2000 4 003-1228 4. SUBSURFACE CONDITIONS Subsurface conditions underlying the Barbee site have been inferred from two (2) borings put down on the site by Shannon and Wilson, and five (5) borings put down by Hart-Crowser. The locations of these borings are presented on Figure 2. The actual logs of the borings are presented in Appendix 1 of this report. 4.1 Soils Subsurface conditions underlying the site are generally uniform, and consist of surficial fill materials of up to about 15 feet in thickness, overlying a natural depositional sequence of delta and/or lacustrine sediments, which are in turn underlain by glacially deposited materials. In general, the natural delta and/or lacustrine sediments underlying the fill include soft organic silts and silty clays, which are interbedded with very loose, silty fine to medium sands. These sediments overlie more granular alluvial deposits which consist of layers and/or lenses of loose to medium dense gravelly, fine to coarse sands, and occasional silts, which are likely discontinuous and characteristic of this type of depositional environment. Localized areas of soft sediments may be present within the alluvium These alluvial sediments extend to depths of up to at least about 60 feet based on the boring logs. The alluvial soils in turn overlie glacial sediments consisting of outwash deposits or glacial till. At the Barbee site, there is an apparent layer of ablation till, which has similar grain size characteristics to lodgment till but has not been overridden by glacial ice, and therefore is not as dense. This ablation till layer ranges from 3 to 12 feet thick and is medium dense to very dense. Very dense lodgment till underlies the ablation till. Rock was not encountered in the two deep borings put down at the Barbee site. 4.2 Groundwater The surficial groundwater level at the site is most likely controlled by the water surface elevations in lake Washington and May Creep which runs along the southern portion of the project site. As such, we would assume that the groundwater surface throughout much of the site area would be at approximately elevation 20 feet or so (depths on the order of 3 to 5 feet below the existing ground surface). The two deep borings advanced on the Barbee property encountered artesian groundwater conditions at a depth of approximately 110 feet below the ground surface. Groundwater recharge for this deep aquifer system is expected to originate largely upon the recessional outwash capped Kennydale hill and within the May Creek Valley sediments. Golder Associates August 9, 2000 5 003-1228 5. PRELIMINARY GEOTECHNICAL RECOMMENDATIONS 5.1 Preliminary Foundation Design 5.1.1 Building Support For planning purposes, we recommend that the buildings contemplated for the Barbee development should be supported on deep foundations bearing in the medium dense to very dense glacial soils that underlie the project site. Foundation types could consist of drilled caissons, open-end or closed -end driven or vibrated steel pipe piles, concrete or timber displacement piles, or auger -cast piles. The actual type of pile, including material, length and installation methods will be based on the structural requirements for the buildings, and an economic analysis of the most cost-effective foundation support systems. Downdrag forces will need to be included in the design of piles. Placement of fill adjacent to the structures could consolidate the underlying compressible sediments, which, in turn, will result in downdrag forces on the piles. In addition, potential liquefaction of these soils, as discussed in section 5.2 of this report, could result in settlements and downdrag forces as well. Additional geotechnical engineering studies will be required in order to provide a better evaluation of the amount of downdrag force which will act on the piles. If the presence of contaminated sediments and groundwater is encountered on the site, special installation techniques may be required for the deep foundation system in order to minimize contaminant migration across the geologic strata during or after installation. As an example, techniques could include the use double casing through zones of contaminated soils or groundwater, or vibration installation techniques. This factor will also play a role in the selection of the appropriate foundation system for final design of the project. 5.1.2 Floor Slabs Support We recommend that the floor slabs for all buildings be structurally supported by the deep foundation system. This recommendation is provided because the underlying sediments at the site are susceptible to differential settlements due to loading and liquefaction potential. Garage floor slabs may not need to be structurally supported, dependent on the slab design and the tolerance for differential settlements. 5.2 Seismic Design 5.11 Liquefaction The fills and alluvial soils that underlie the site to depths of up to about 60 feet are very loose to medium dense, and potentially susceptible to liquefaction during an earthquake. Golder Associates August 9, 2000 6 003-1228 Liquefaction of these soils would result in a loss of shear strength of the soil or the capacity of these soils to adequately support structures supported on shallow foundations. Additionally, the potential development of liquefaction within these soils could result in vertical settlements, and/or lateral spreading of these soils near the shoreline area. The effects of liquefaction on the performance of the building structures can be mitigated by the use of a deep foundation system, which would transfer the building loads to the dense glacial soils beneath the potentially liquefiable alluvial deposits. The foundation system would be designed to withstand the design earthquake and the effects of liquefaction. Site improvements, such as containment walls, may be needed along the shoreline area to mitigate the hazard for lateral spreading. Without such mitigation measures, structures located along the shoreline may experience potentially damaging lateral deformations as a result of liquefaction due to earthquake loading. Detailed analysis of the potential for lateral spreading will depend on the subsurface topography along the Lakeshore, and the structural details of the shoreline development. These analyses can be carried out in subsequent phases of the project. 5.2.2 Preliminary Seismic Design Criteria The site would fall within Zone 3 (seismic zone factor z=0.30g) based on the Uniform Building Code (UBC,1997). Furthermore, based on the soils data on the borehole logs, we would classify the soil profile as SF, requiring a specific investigation and analysis in order to ascertain the ground response to earthquake events. This can be analyzed in subsequent phases of the work 5.3 Site Preparation It is our understanding that site fills on the order of 5 feet or less will be constructed to accommodate the site grading requirements. It is unlikely that this level of filling will cause significant settlements. However, as previously discussed, settlements could be induced as a result of soil liquefaction due to earthquake shaking. Therefore, we would recommend that precautions be taken to minimize the potential impacts of these ground settlements, such as an increased pavement section for roadways and parking areas, and the use of flexible utility connections. Golder Associates August 9, 2000 7 003-1228 6. USE OF THIS REPORT This geotechnical study has been prepared exclusively for the use of the Barbee Mill Company and their consultants for specific application to the Barbee Mill site development. No warranty, expressed or implied, is made. Our work did not include any subsurface investigations. Our work was based solely on data describing the site conditions that was carried out by others. We have relied on that information in the preparation of this report. Once the site development concepts are finalized, additional geotechnical investigations will need to be undertaken to determine the specific geotechnical conditions and provide final geotechnical design recommendations for the site development. In addition, our scope of work did not include any environmental screening or assessments. This work will be carried out by others. Golder Associates FIGURES Golder Associates F FIGURE 1 VICINITY MAP BARGEE MILL PROPERTY Golder Associates m) ........... O .. HG W-w HGMW-0f 7 CD srve•� 1 L EGEND Number and approximate location Hcm -123 of borings performed by Hart-Crowser, 9198 *� �+ Number and approximate location of borings performed by Shannon & Wilson, 3/97 O x Proposed building 0 100 200 FEE Reference: Original AutoCAD drawing provided by Triad Associates Job Number 00-153 7114100 FIGURE 2 SITE PLAN BARBEE MILL PROPERTY APPENDIX 1 LOGS OF BOREHOLES Golder Associates JUL-31-2000 15:07 CENTURYPACIFIC 206 689 7210 P.09/30 IMto 7rsn MATERIAL DESCRIPTION a e Standard Penetration Resistance t E :3 La (140 lb. weight, 305 drop) o ?r o A Blows per foot Surface Movation: Approx. 25 Feet 0 406 Asphalt and base. 03 Z6 4.0 Gray SAND., moist; Sr. Loose gray, fine to medlum sandy GRAVEL; moot, trace of wood fragments; 21 (FIII1 GW. 7.4 a z Loose, fine SAND; gray, slityr wet et feet; (FiU71 SM. r { 4= e� c 10 a # Stratified, loose, gray, fine to medium SAND and very soft, brown, slightly sandy 1ss SU and silty fine SAND; wet; (Fine eI 15 - Allu�tram} SPMII_ .. Very loose to loose, gray. slightly clayey. �� •� :: :: organic silty, fine SAND and fins sandy 20.o 20 :. SILT; wet: lenses of coarse sand and .� .. clayey silt; trace of organics; (Fine Iivvk=VEkipression Filling) • ......... SM/ML. 1e= 25 :: ; - ; :: ... Medium dense to dense, gray, trace silt to silty, sandy GRAVE., locally gravelly sand; wat; (Coarse Alluvium) GM-GW. 12T 30 ...... :.:. a4•Q I 1a= u= 35 ...... Very dense to medium dense, gray, clean .... to silty, fine to coarse SAND grading to slightly silty to silty, sandy GRAVEL; wet: G = :.: .... {Medium to Coarse Alluvium} SP-SMIGP-GM. 42.4 t ta= iJT L ::: :: ... Medium dense, gray, slightly silty, sandy GRAVEL, grading to gray, silty, sandy . : - .. . GRAVEL; wet; layers of gray, fine to 45 rnedium sand; (Medium to Coarse • Alluvium) GP -GM. E tsI s=.o m= so •:.. : :: :: Loose, brown, fine to medium SAND, traee of gravel, grading to silty SAND; wet •I ; .....: - - - ::. = = to moist; lenses of gray, slightly clayey silt sg,p r 21 55 : • End gray, slightly clayey, sandy silt; ' .. ; .... . (Medium Alluvium SP=SMIML. �� LK b 0 20 40 5 % Water Content Sample Nvt fieoavored ® Surface Seal X 2' D.D. Split Spoon Sample ® 'Annular Sealant Piestic limit 1--� 1Squid Limit Q 3` O.l). Tube NaWrsl Water Content Shelby sample ITT] piemmstm screen ♦� Grout !3 water I_+ai+t'I JAG Developmfutt Renton, Washington NOTES ,. GoatYaea. end aw i �� be ga" � °�'°� aetM►va► LOG' OF BORING SWB-7 2. Tim trk--1 m In the taxi of this report Is nee ary for a prapar urdenamnc v of the nature of eubsurfar a Meteriefe. 3. Water level, tf hecated drove, is for the data specified and may vary. December 1996 W-7443.03 4. Refer to KEY for aWaneboo of 'sprhars' and definitions. SHANNON & Wa.SON, 1NC. FIG. A-7 5. uSC fencer syn" based an visual dmitertipn. a.�owehftW «a EnWkQFWP5Md CaruK.ne. Street I of 2 JUL-31-2000 15:07 CENTURYPRCI1'IC MATERIAL DESCRIPTION Surface Elevation: Avnrox. 25 Feet {Lacustrine Deposit) ML. Medium dense to dense, gray, slightly silty to silty, fine to coarse SAND, trace of gam; molst (Ablation TIIQ SP-SM. Very dense, slightly oft, Coarse SAND, trace of gravel; wet; (Till) SP-SM. Very dense, oft fine SAND, trace of gravel; moist: increasing gravel at 85 fact; = Sig-SM. aura, gray, silty CLAY: moist; locaiij laminated (Glaclolacustrine deposit)) CL-M Very dense, silty, sandy GRAVEL grading to slightly silty, sandy GRAVEL; watt fractured rock at 110.5 feet; wood at 111 feet; artesian conditions at 110 feet; lice -Contact Deposit) GP -GM. COMPLETED 11 /20196 LEI;i±Nn 206 689 7210 P.10f30 o e Standard Penetration Resistance CL u 1140 lb. weight, 300 drop) y- 12 ?y A Blows per foot a n _ in an sample Not Recovered ® surface Seal S 2. O.D. spat Spoon Sample ® Annular Sedent �i 3. O.D. Shelby Tube 3ampla p'W=meter Screen ® Grout Water Level NOTES 1- Yha atrsdrtcadun line rsQrssant the apprsAmata bwmdarles batw. aai types, and the tronsWM may ho eredNal. . 2- The Sommsion in the text of this rspoK is nsaessery for a proper � of the nffwm of *vb*urfaas meterids. 3: Water lovot, if indicated above, is for tM data specified and msy very. 4. (der to KEY for sotphnation of -Symbols- cool ,,Wm tioni. S- Usc ist w wymbal based on viseal dsafico iwL 65 .... Sara• 70 :::..:: 75 .. ::::: 80 85 90 ... 95 100 :: ..... 105 _.., 115 ..... .. 0 to 40 15C • % Water Content Fleatic Limit V- 4--A Liquid Limit Natural Water Content JAG Diweiopmertt I Renton, Washington LOG OF@ORiNG SWB-7 December 1996, W-7443-03 sNANNON & WiLSON, INC. I FIG. A-7 c, o . , , er .,a rM&MMM" C&Nk*uar. sheet 2 of 2 JUL-31-2000 15:07 CENTURYPACIEIC 206 689 7210 P.11/7m MATERIAL DESCRIPTION �+ a o -o e c Standard Penetration Resistance •_ . 1 E r 0 40 lb, weight, 30' drop) ' o Blows per foot Surface Elevation: Approx. 22 Feet f� 20 6 Asphalt and base. 0.2 t ° z'° -l- t J,. : - .. .: • .... = _ ..: : : Dark brown SAND; molst; SP. � Gray SANG; and GRAVi,; moist; SPlGP. i 21 � Very loose to loose, gray, slightly silty, : ; gravelly SAND; moist; wet at 8 feet; scattered wood places; orgenlcs sons and silt chunks: locally trace of clay, (Fill) tt.o t 10 .. SP-SM/GP. a= ;` = = ::. ' Interbedded, loose to medium dense, pray. fine to medium SAND and brown, slightly °� t 5 = ' = ..... ' . ' = sandy, peaty, organic SILT; wet; lenses of wood fibers end peat: gravels noted at s= :S117.5 feet; (Medium Alluvium/Depresslon Filling) SP/OH. °= 20 :.: .... . , gray, silty, fine to medium SAND; I rganic lenses and partings; )Medium to= 25 ' ' ; ; ; • um) SP-SM/ML. 27.0 2s.o t 11 , gray. sandy, fine GRAVEL: wet; ar to subrounded; (Coarse Alluvium? :s= 30 ran 31.0m dense, gray, slightly gravelly, ly clayey, silty SAND; wet; organics; 34.0 141 35 .: : ..Alluvium) a .•m :. . ..: ., SM. 0■ dense, gray, fine to medlum trace of gravel; wet; (Medium■ ::uml SP. ©• te� 40 ......... Medium dense to dense, gray, sandy, fine s.o n= to coarse GRAVEL, local trace of; sill; wet, mud bubbling at 37 feet; (Coarse 4a.a uvlum) GW,° : - - - : ' ........ Stiff, brown. slightly clayey SILT; wet; (Lacustrine Deposit) ML. Jai dense Very to medium dense, pray. slightly clayey, trace to gravelly, siky SAND; moist; {ice -Contact DepasitslAblation Tllq SM. 50.0 20 55 ..... .. ::: Dense to very dense, gray, slightly silty to _ silty, f'irte to medium SAND; .wet; gravelly t ::..- ... CONTINUE NWr PAGE .... . LEGEND 0 20 44 60 Sample Not Recovered M3 Surfeae Seel � % Water Content 2 2' O.D. Split Spoon Semple Annular Sealant F'kwc Limit 1-4-1 Wuid Limit Natural Water Content Z 9" D.D. Shelby Tube S ernpk l� I'iamrnatar Screen ® Gaut _ g Water Level JAG Development Renton, Washington NOTES t toms orm6fiewiJon f; er be o ' b°'"'�"d°` b"""�' trr lt types, end the rrs�tian .OLOG OF BORING SWB-10 2. The dlemisslan in the text Of this repert is necessary for a proper undastsndWV of the nlawe of elxiudi mauwWv. s. water level, if indicated above, in for the date spodfied and may very. 1JeGfmber 1995 W-7443-03 4. Refer to KEY for expfonodan of 'Syrrhole' and deanWom. 5. use fetter SHANNON do WILSON, WC. FIG. A-� sYrnhol Ihasad an vistisl deasffiwsdon. c°oadnbd..r Fn.k,�,.,,re OWWA ■1s Sheet 1 of 2 JUL--31-2000 15:07 CENTURYPACIFIC 206 689 7210 P.12/3e MATERIAL DESCRIPTION ► $ I u Standard Penetratlon Resistance M CL E a M (140 th. weight, 30" drop) a : A Blows per foot Surface Elevation: Approx. 22 Feet at 64 to 66 feet, 75 to 77 feet, and 79 21 feet; (Glacial Outwash) SP-SM. n= 70 75 ,. At T- xs $0 = ... • • Very dense, pray, fine sandy SILT; moist; .... �13 scattered layers of gravel; artesian conditions at 85 feet: (TM) ML. as132.0 :..... .. _ Dense, gray, siiphtiy silty, fine to n+ediurn SAND: moist: layer of silt with trace of .:.. .::. ; - . . Gravel; gravel at 97 feet; strong artesian 85 conditions at 111 • feet; [Glacial Outwashl •i .. ' ' ' SP-SM. + _ 25 100 ....:0: . i 105 # 110 ....... ----. ..... 261 - BOTTOM OF BORING.....:: COMPLETED 'I 1I11198 1. GEND 0 20 40 60 • % Water Content Semple Not Rar�avored f21� surface goal Y 2" O.D. Split Spoon Sample ®; Annular Sealant Plastic Limit 1--" Liquid Limit X 3" O.b. Shelby Tube Sample Piiezamater Screen Natural Water Content ® Grove Y Water Level - JAG Development Renton, Washington NdTES I. The at.stific tiara lines raptaant the avppfoxkoste bmmdariea between set �. m-A the a.rr.inan may be aradual. LOG -OF BORING SWB-10 2, The 4amss9at in the text of dsis report is necessary tar a proper undo ttwWma of ttm nature of subsuMaoe trlrtetiafa• 3. water level, if indcseM above, is for the date opadfendDecember 1998 Waaa -03 d may vary. 4. Rarer to KEY for c*--tton of 'Symbols' and definitions. SHANNON & VI LSON, INC. FIG- A-9 5. USC latter ryrr� based on viaud ctasdriew", a"Ndn" end raNiw„�.uo G—ut" Sheet 2 of 2 JUL-31-2000 15;06 CENTURYPACIFIC 206 689 7210 P.07/33 Shamm & WMson, Inc. (S&VV). uses a sail aUssif=11on system modified from the Unified Sa CtassiRmtion (USC) System. Elemen% of the L1SC and ether definitions are provided on this and the following page. Soil dasaipt'w we (used on visual- mam ai procedures (ASTM D 24W93) finless otherwise rKAed. S&W CLASSINCATION OF SOIL CONSTITUENTS • iWOR cwwftuwb compose more than 50 perceM by WW9. of Ise son. Mellor wnstibersts are capitafted (SAND). War cormtihrents compose 12 to 50 percent of the salt WKI precede 11B major Corwauents (Oy SAND). Minor consti+msents pr*ceded by 'Ahttr compose 5 to 12 permd of Ise sW (srjgNta Silly SAND). • Trsca consdWants campoo 0 to 5 p8mant of the sd (alightty &My SAND. trace of gmmQ. MOISTURE CONTENT DEFINITIONS Dry Hof M01000, dusty, dry to Moist Dane bt4 no visible water Wet �bie free water. from below water ABBREVIATIONS AID At Time of Drilling Bev. eevatlon It feet HSA Hollow Stem Anger ID Inside tUrneter ur imhes is pounds Mon. I Mond cover N SUMS for last hun 64nch kwernents NA Not Appiicabfe or Not Avaibble OD Outaitfe DiarrwW OVA Organic Vapor Analyzer PID PhoWanizatfon DeiectAr PPm Pub Per mktlort PVC PotMgyl Chloride SS Split Spoon sampler SPT Slanderd PenetredonTest USG Unified sal CWelficatkm WU Water Level indicator GRAIN:SIZE DEFIIZIMMS BESCRItrtION' sh. 91Etr£9tZE FINES a Om (0t08 mm) SAND' • Fr a • 4200 - f40 (OA mW • MedlUM • t40 - r110 (2 mm) - Comsa - 010 - #4 (5 mrn) GRAVEL! • Fine • R4 - 3/4 Inch •Coarse • 314 - 3 Inches COBBLES 3 -12 inatos BOULDERS a 12 Inches Unless ottwrwtse noted, sand and gravel, when presant, mop from line to coarse in grain size. RELATIVE DENSIYY / CONSISTENCY CoaASE-GRIUNED SOBS RNE-QRArt'tlr0=NEsnrE SOILS N, SPT. RELATIVE N, SPT, RSL AnVE BLOWS1FT. DENSITY 81-OW$lFT. CONSISTENCY o - 4 Very kme 4 "It 4 -10 Lease 2 -4 soft 10 - 30 Medium derm 4-8 Madhrm stlff 30 - SO Dense U -15 Still Over 50 Very dartse 15 - 30 Very &W Over 30 Hared WELL AND OTHER SYMBOLS o Cernenr/Concrete - AS ftft or PVC Cep amBentonile Grout ® Cobbles sentonite saw FAI I/I`� SloUgfl g'Q Ash Silka Sand Bedrock go2` I.D.PVC Screen (0.0104neh Slot) JAG Development Renton, Washington SOIL CLASSIFICATION AND LOG KEY February 1997 ' W-7443-04 SHANNON do WIL.SON, INC. I FIG. A-1 Geole and Eslvirornrier►tsl Imr► Sheet t Of 2 JUL-31-2000 15:06 CENTURYPACIFIC 206 669 7210 P.09/30 UNIEIEp SOIL CLASSIFICATION SYSTE.0 MAJOR OPASK M$ 3 WRIAOISP TYPICAL DESCRIPTION � sa% Ctean Gran rrarrUbduraa, six Aneaj W114kaded Gawals, QIYI� LMla ar No Rrwa Poorb [dad t�rava� cvar-Sand Mures, Little or No Rnag lamwats wtth0 nraa 1 ) SKY Gravels. araveksarwi ll Mhduras Cuefse-Grained Solis ( a►� No. 200 slays) haclbn table ed on Nm l slow) clam Gravels, oravebswd-clay Mhdur" Sande cr nacre of camas AndAw ry cwaar, sand r than(50% L'% dnssl w.�cl�od Sonde, araysify sandrn We of No Rnes jLJss Ouarb�r mots Vie. GF�,��ij10 Poorly Graded Sand, Onavrily Sands6 LUe or No Flies 0 SM Sy sands, Sand-51It Midxes SC Clayey Sands, SUW relay Mbduais fhan 12% funs) lip Wft Sit or Law to Median - ML Plastift Rock Pfour, at Clayey Sft Sips and Gays Mqw n 50) dean Itrorganic With iv Plsway SN C 11 InorPwic Clays of Low to modkin PtetUy. Gmvellq Clays. Sandy CWy% SClaysan , tClays alt' Orgedc vL Orpnic Sft Clays of Pd*-G b*d Sons CFI Clays al Medbm 10 High Cy, sandy Fat Clay, Gravelty Fat Na sl0 and Clayc (lfgald In* s0 or miles) tno7gartifc ClaySilts MH inorganic seta. Micaceous or DYtornacaaus Fb*& Sands or Silty Sills, Ebsdc FA Cleat OH Orga* Clays of Medium to HO Piastf *, Omaric Sao 16gNy OWnic Sate Primarily organic matter, dark In color, and orgamic odor PT Peak Humuo, Swamp Soft with tdgh Grgaak Comteatt 009 D 4427-0) NOTES 1. Dual syrT bola (Gymbots separated by a hyphen. i.e., SP-SM, s{i * silty fine SAND) are used for sots with b0meen 5% and 12% or when the liquid runt and Plasticity index values plot in the CL-ML area of the ptasd* chart. Z Borderline symbols (syriftft separated by a slash, i.e., CtJAAL, silly CLAY/cteyey SILT: WSW. sandy GRAVEUgravey► SAND) kamted that the sbil may fall into one of two posslbfe basic groUP& I JAG Oeveiopment Renton, Washington SOIL CLASSIFICATION AND LOG KEY February 1997 W-7443-04 SHANNON & WILSON. INC. I FIG. A-i G0'"d�o0^ Sheet 2of2 AUG-01-2000 69= 3e HART CROWSER, I NC . Boring Log and Construction Data for Monit"Ing Nei HCHN-AD Geologic Log sample N O� 3 inches of ASPHALT over medium Cense, damp, drown, san GRAVEL. Very loose to medium dense, moist to Net, q gray, medium fine SAND with oumimal silt lenses and occasional wood fragments. 5--2 7 5-3 14 5-4 a 5-55 3 5-5 2 10 Very soft to soft, wet, Grown, sandy ✓organic SILT with sand lenses to 3 inches 5-7 I and wood. 5-B 2 5-9 3 j LOOS@ to nedLum dense, wet, gray, medium line SAND with thin 50t layers. 5-1d 9 s-u a S-1z 16 20 Bottom of Baring at 20.0 Feel. Completed 0/25198. 25 30 1_ Ref9e to Figure A-t for ex0lanalion Of desoriptions and symbols. 2. Sag descripticna and str4tum lines are interoretive and actual changes may ae granual. 7. Ground water level, if Indicait<0, IS al tree of dr%ling Ie7Ci or for date specified. Level May vary with time. 206 329 8964 P.04/09 Monitoring Well Design iff DTI} .I W. I �. r AU-1-01-2000 09:39 HART CROWSER, IHC. 206 329 2964 P.05/09 Badng Log and Construction Data for MoNtaft NW HCHN-2 Geologic !-Dg Monitoring well Design CaskV Stickup in Feel. -0.3 dF Ls� Sample N CN 3 inches of ASPHALT over meOWm dense, mpi$t, Drown, sandy -S'AA VGL- - — medium ciense, moisi, gray. medium fine SANG With trace graVelS anti wood. 2t No recovery. *S-z 34 Am Lvose to mecum dense, wet, gray. gravelly SAND witm cobbles. S-4 12 Ic grown, or an�c 51Li. Soltont of Boring at 10.0 Feet. `Urnoleteo MUDS. 20- 25- 30— I- Ftet@r to Figure A-1 for explanation of descriptions and SYMMIS. 2. SO Oescriplions ot%d stratum NnLst are interpretive HdM7CW"5M and actual changes may De gradual. 3. Ground water level, it ihd ated, is at time of drilUng (ATO) or for Cale specifieCk Level may vary with time. FAP" A-& G-01-2000 09:39 HART CROWSER, INC. Boring Log and Construction Dots for Monitoring Me# HCMN-3 Geologic Log w U. 0. Pi 15 20 sample N ASPhalt over loose, mo13t to wet, gravelly, medWm to Uibrte SAND with salty layers. Graae5 to non -gravelly with wood chips, Bolton of Boring at 9 Feet. I. Refer to Figure A-1 for explanation of descriptions WI IyMDOK 2. Soil descriptions and s1ralum lines are interpretive and actual changes may Ce gradual. 3. Ground walec level, it indicated, is at time of drilling IATO) or faf date specoheC. Level may vary with time. 206 329 8964 P.06/09 Monitoring Well Design C6SIMQ Stickup in :eet: -0.3 Am AW 1AWKNORMW J_IW_* go" F%WV A-0 AUG-01-2000 09:39 HART CROWSER. INC. �orir Lod and Construction Date for HOW Me# HCNN-4 Geologic Log Sample $-1 S-2 1. Ref or to;42w0 A -I for explanation of descriptivrss and symbols. 2. SOO aescriplions anCI strdtum lines are interpretive and actuai changes may be 9raduel. I GrounCl weter level, if indicated, is a) time of Orilling (ATp) or for date specified. Level may vary with time- N 14 14 206 329 8964 P.07/09 Monitoring Well design rf HAOUCRWIM FOM A AUG-01-2000 09:40 HART CROWSSR, INC. 206 329 8964 P.09/09 Bor#V Log and Construction Data for MoWtoriing No# HC11w-5D Georgic Log Monitoring Well Oesign �u u, Sample N o .l= 0 Loose, damn to wel. gray and brawn, non -silty to voty silty. medium to line SAND. I n +J Interbodded, stiff, wet, brown PEAT, gray SILT. and medium dense. gray, nedium SANG. 15 2 Dense to very dense, wet. gray, fine to McCium SAND_ 25 5-4 1 x t 17 5 -s 1)(1 74 Grades to me0vrn to coarse SAND with s-6 36 aavel, 9Ot1oM of Borinn�g at 20 Feet_ 30 Complete, U.M. 1. Refer to Figure A-1 for explanation of descrtplions and symbol. 2. Soil deficriplions and stratum tines are interpretive and actual changes may be gradual, 3. GroUrid water level, if Indicated, is at time of Grilling (ATD) or for date 5pecified Level may vary with time. D v FW40 A—M TOTAL P.139 ULM Of - 173 (1) THE TRAN5PO GROUP INITIAL TRANSPORTATION ANALYSIS for Barbee Mill Property Prepared for: Triad Associates August 8, 2000 INITIAL TRANSPORTATION ANALYSIS for Barbee Mill Property Prepared for: Triad Associates �' p �ISTSg SJ� IV AL TC•t1 August 8, 2000 f Ex RES 12 / 1.5 Prepared by: The Transpo Group, Inc. 117301181h Avenue NE, Suite 500 Kirkland, WA 98034-7120 (425) 821-3885 FAX: (425) 825-8434 INITIAL TRANSPORTATION ANALYSIS for Barbee Mill Properly r Prepared for: Triad Associates August 8, 2000 Prepared by: The Transpo Group, Inc. 117301181h Avenue NE, Suite 600 Kirkland, WA 98034-7120 (425) 821-3665 FAX (425) 825-8434 TABLE OF CONTENTS Page INTRODUCTION.................................................................................................... I Project Description..................................................................................... I EXISTING CONDITIONS... ....................................................................................4 PLANNED IMPROVEMENTS AND DEVELOPMENT..................................................5 PROJECT TRIP GENERATION...............................................................................6 PRELIMINARY TRAFFIC ASSESSMENT..................................................................8 SITEACCESS........................................................................................................9 SUMMARY... .................. ............................................................................. 10 FIGURES 1. Site Vicinity......................................................................................................2 2. Site Plan...........................................................................................................3 TABLES 1. Barbee Mill Redevelopment New Site Trip Generation........................................7 2. Net New Trip Generation...................................................................................7 Initial Transportation Analysis — Barbee Mill Property August 8, 2000 INTRODUCTION The following report summarizes the traffic characteristics associated with the proposed mixed -use development on the Barbee Mill property in Renton, Washington. An overview of the project, existing conditions, planned improvements and development, project trip generation, and traffic operational characteristics are provided in the following sections. This overview is intended to provide the City of Renton with an understanding of the project and associated transportation characteristics. Project Description The project site is located on the west side of Lake Washington Boulevard just south of the NE 44th Street interchange at 1-405 within the City of Renton. The project site location is shown in Figure 1. The site currently contains several buildings that are part of a sawmill that processes specialty cut lumber. The proposed project would remove all existing buildings, with the exception of one, and convert the site into a mixed -use development. The development proposal includes approximately 619 condominium units and 200,000 gsf of commercial space in a total of nine (9) buildings. The preliminary site plan is shown in Figure 2. Vehicle access would be provided via an extension of Hazelwood Lane from Lake Washington Boulevard. The extension would create a two-lane roadway into the site, with several cross -streets to provide access to the various buildings and public areas_ Pedestrian and other non -motorized access would be provided through a combination of sidewalks along the internal roadway network and dedicated pathways. Non -motorized and emergency access is proposed at the existing Barbee Mill driveway on Labe Washington Boulevard; this access point would be used for emergency purposes only. All parking would be provided within the site in mostly parking garages, with a minor amount of surface parking lot space. A total of 1,948 on -site parking stalls are proposed_ 1001002014pWiatstudyr O The Transpo Group, Inc. 2000 Page I MA0010020 ftoreligraphictodr Figure Z Ste Plan BarbeeMWPro" 0 W MiWoa¢ itowaotrt t rocO woom tndial Transportation Analysis — Barbee MY1 Property August 8, 2000 EXISTING CONDITIONS The site is served by Lake Washington Boulevard via Hazelwood Lane. Lake Washington Boulevard (LWB) has two travel lanes (one in each direction), with bicycle lanes on both sides and intermittent sidewalks as development has occurred. The roadway is classified as a collector arterial and the posted speed limit is 25 mph. It provides access between I-405, the Kennydale neighborhood, Gene Coulon Park, and Boeing Renton Plant to the south. Hazelwood Lane is a two-lane local roadway with gravel shoulders and a posted speed limit of 25 mph. The roadway serves as local access for residents to the north. Approximately 1/a mile north of Lake Washington Boulevard the Lake Washington public bike trail connects to Hazelwood Lane. Regional and local vehicle access for the Barbee Mill property is primarily served by the NE 441h Street interchange at I--405_ The interchange is in a partial diamond configuration with stop control on the southbound off -ramp and a traffic signal at the northbound ramps. The northbound on -ramp is a loop ramp, thus deviating from the diamond configuration. The on - ramps both have HOV lanes with ramp metering to provide priority to carpools and transit. The southbound ramp intersection is located approximately 130 feet east of the Hazelwood Lane/Lake Washington Boulevard intersection. NE 44th Street is classified as a collector arterial, with 3-lanes across 1-405 and widens to 5-lanes east of the interchange. 10010020f "Vnitialsludy r 9 The Transpo Group, Inc. 2000 Page 4 Initial Transportation Analysis — Barbee Mill Property August 8, 2000 PLANNED IMPROVEMENTS AND DEVELOPMENT The site is located in an area that is currently under significant review and consideration by the City of Renton and WSDCT, and by other private developers as part of several potential development proposals. To address growing transportation needs, the City is currently reviewing alternatives for interchange improvements. The concepts being evaluated are intended to "provide for and facilitate the inclusion of full multi -modal and intermodal improvements in capacity, access and connections." City staff indicated that an improved diamond interchange is currently the alternative most favored. Private development efforts within the area could potentially increase traffic on Lake Washington Boulevard and at the NE 4411, Street interchange significantly. In addition to the Barbee Mill property, two parcels to the north have also been discussed as future mixed -use developments. Port Quendall and the J_H. Baxter Company properties, when combined with Barbee Mill total 67 acres. Barbee Mill would potentially account for 10 percent of the commercial development and up to half of the residential development. It appears that the majority of vehicle access for these parcels would be located hake Washington Boulevard via ,Hazelwood Lane. The configuration of the interchange as well as potential development density in the area will effect the overall traffic operations within the area and the degree of Barbee Mill transportation impacts. WA002011*pVnifialstudy r © The Transpo Group, Inc. 2000 Page 5 Initial Transportation Analysis — Barbee Ml! Property August 8, 2000 PROJECT TRIP GENERATION Project trip generation was estimated using methodologies consistent with the ITE Trip Generation Manual, 6th Edition. The type of traffic associated with a large mixed -use development such as the Barbee proposal consists of new trips and captured trips. The combined effects of new and captured trips represent total project trip generation. A credit can also be applied to the project trip generation to account the existing land uses that will be removed or renovated to estimate net new traffic to the surrounding roadway system. The proposed development is expected to consist of 619 condominium units with a total of about 200,000 gsf of commercial space. The commercial space would consist of 112,000 gsf of office space, 50,000 gsf of retail space, 8,000 gsf of restaurant space, and a 30,000 gsf hotel. This specific breakdown of commercial uses was used to estimate project trip generation. Due to the mix of land uses and connectivity within the site, there is expected to be a share of trips that would be generated within the site and would not impact off -site roadways or site access points. These trips are characterized as "captured trips." The following three types of captured trips are expected to occur: (1) accounts for those residents that are expected to live and work on -site, which is expected to account for about 5 percent of total residents. (2) accounts for those residents that frequent the retail or restaurant uses on -site, which is expected to account for about 10 percent of residential trips. (3) those generated by office employees or patrons to and from the restaurant, retail, or hotel land uses. This component is expected to account for about 5 percent of the office trip generation. The share of captured trips is generally based on studies conducted and documented in ITE Trip Generation, and has been used as the basis of similar approved developments within the region. Table 1 summarizes the estimated site related trip generation. It summarizes the total and captured trip components, which are used to arrive at new project trip generation. 400100201IwpVnitialstudy r © The Transpo Group, Inc. 2000 Page 6 Initial Transportation Analysis — Barbee Mill Property August 8, 2000 Table 1. Barbee Mill Redevelopment New Site Trip Generation ITE Daily AM Peak Hour PM Peak Hour Land Use Type Size Land Use Rate Trips Rate Trips Rate Trips Condominium 619 DU 230 5.86 3,600 0.44 275 0.54 335 Res/Office Captures 5% -180 5% -14 5% -17 Res/Retail Captures 10% -360 100/0 -27 10% -33 Office 112,000 sf 710 11.01 1,250 1.56 175 1.49 165 Res1011ice Captures -180 -14 -17 Otfice/Retail Captures 5% -60 5% -9 5% -10 Retail 50,000 sf 814 40.67 2,050 6.41 320 4.93 245 Restaurant 8,000 sf 831 89.95 710 - - 7.49 60 Hotel 30,000 sf 310 8.23 250 0.56 15 0.61 20 Res/Refail Captures -360 -27 -33 Office%Retaif Captures -60 -9 -10 Total Trip Generation 7,860 785 825 Captured Trips 15% -1200 13% -100 14% -120 New Site Generated Trips 6,660 685 705 To estimate project impacts, it is necessary to credit those trips currently being generated by the project site. The site currently contains approximately 117,000 gsf of warehouse and office space. The type of facility and daily operations at the Barbee Mill most closely relates the Light. Industrial land use category defined in the ITE Trip Generution Manual. Table 2 summarizes the net new traffic generation, based on the difference between site generated traffic and estimated trip generation currently on -site. Table 2. Net New Trip Generation Description _ Daily AM Peak Hour PM Peak Hour New Site Generated Trips6,660 685 705 Existing Barbee Mill -820 -110 -115 Net New Trip Generation 5,840 575 590 i See Table 1 for description of trip generation for new site proposal 2 Based on ITE Land Use 110, Light industrial and 117,000 sf As shown in Table 2, the net increase in weekday traffic on the surrounding roadway system is expected to total 5,840 daily trips, with 575 occurring during the AM peak hour, and 590 during the PM peak hour. Of the weekday PM peak hour trips, approximately 62 percent, or 365 trips, would be entering trips (approaching the site) while approximately 38 percent, or 225 trips, would be exiting the site_ 10010020Awplindiaf study r 0 The Transpo Group, Inc. 2000 Page 7 Initial Transportation Analysis — Barbee Mill Property August 8, 2000 PRELIMINARY TRAFFIC ASSESSMENT A review of the estimated net new trip generation, likely travel patterns, the existing roadway system, and existing traffic volumes were conducted to generally assess conditions with the proposed development. Weekday PM peak hour traffic on Lake Washington Boulevard west of 1-405 ranges between 150 vehicles per hour (vph) in the north -eastbound direction and 450 vph in south - westbound direction. Project traffic is expected to primarily use the NE 44th Street interchange for access, with a smaller percentage of traffic utilizing Lake Washington Boulevard to the south. If a total of 80 percent of project traffic were assumed to travel via the NE 44th Street and 1-405, this would equate to approximately 180 PM peak hour trips in the north -eastbound direction (exiting the site) and 290 PM peak hour trips in the south - eastbound direction (exiting the site). The addition of project traffic would increase PM Peak hour volumes to 330 vph in the north -eastbound direction and 740 vph in the south - westbound direction. Based on the roadway cross-section, Lake Washington Boulevard has a theoretical volume capacity of 1,030 vph in each direction. Thus, the addition of project traffic alone could be accommodated by the existing roadway facility. Intersection operations at the I-405 ramps would likely degrade with the addition of project traffic. The study underway by the City of Renton is expected to account for the development potential along Lake Washington Boulevard, including the Barbee Mill property, when identifying future improvement needs. Financial contribution by Barbee Mill and other private development may be required in the form of proportionate share fees or a LID as a result of the study, since the interchange project is largely unfunded at this time. WOW0201Iwp4inj atstudyr 0 The Transpo Group, Inc. 2000 Page 8 Initial Transportation Analysis — Barbee Mill Property August 8, 2000 SITE ACCESS Vehicular access to/from the proposed Barbee Mill site is currently proposed via the Hazelwood Lane extension connecting into Lake Washington Boulevard just west of the I- 4O5/NE 44th Street interchange. The Barbee Mill property represents less than a third of potential new development to utilize the Hazelwood Lane/Lake Washington Boulevard intersection. If it were not in such close proximity to the interchange it would likely operate sufficiently as a widened, signalized intersection. The NE 44th Street interchange study will likely address the Hazelwood Lane/LWB intersection due to its proximity. Assuming a recommended and funded solution is identified by the City of Renton, project impacts are expected to able to be mitigated. Vehicular access to the site could benefit from a secondary or even shift in primary access to Lake Washington Boulevard in alignment with N 4Oth Street. While the City's comprehensive planning for this subarea recommends consolidated access for new development, a secondary access point would relieve congestion at the Hazelwood Lane/LWB intersection.. Depending on potential shared access with parcels to the north, this location could serve as a logical location for a second signalized access point. It would also improve access to the residents located on N 401h Street and developments east of Lake Washington Boulevard. Pedestrians and bicyclists are well served by the proposed site layout. Non -motorized access is provided at the proposed southerly emergency access. Connectivity to the north is also provided via the Hazelwood Lane extension_ No transit service is currently provided on Lake Washington Boulevard adjacent to the site_ 1001002014pVadjalstudyr 0 The Transpo Group, Inc. 2000 Page 9 Initial Transportation Analysis — Barbee Mill Property August 8, 2000 SUMMARY The proposed Barbee Mill development is expected to generate about 5,840 new daily trips to the surrounding roadway system and up to 590 new peak hour trips. The adjacent roadway appears to have sufficient capacity to accommodate the increased traffic volumes. Intersection points along Lake Washington Boulevard at Hazelwood Lane, the 1-405 ramps, and potentially N 40Lh Street will likely require intersection improvements (such as widening and/or signalization) to accommodate the increased demand. Intersection upgrades could improve site access operations while mitigating project impacts. Non -motorized travel is well served by the proposed site plan, the existing facilities, and planned facilities within the area. Transit service improvements could help reduce vehicle impacts. While not assumed in the project trip generation, it is expected that a development of this nature would generate some demand for transit service and ride sharing opportunities. W002014w*Aial study O The Transpo Group, Inc. 2000 Page 10 LDtA b%' 173 ( � ) WETLAND DETERMINATION REPORT ON THE JAG DEVELOPMENT PROPERTY Renton, Washington O� Cl7DypCM��lyy-�' ON VED Prepared for: Mr. Jim Spitze CNA ARCHITECTURE GROUP 777 - 1086 Avenue S.E., Suite 400 Bellevue, Washington 98004-5118 CAAX0015 Prepared by: DAVID EVANS AND ASSOCIATES, INC. 415 11Sth Avenue S.E. Bellevue, Washington 98004-6477 f: Revised May 1997 DAVID EVANS AND ASSOCIATES, WETLAND DETERMINATION REPORT ON THE JAG DEVELOPMENT PROPERTY Renton, Washington Prepared for: Mr. Jim Spitze CNA ARCHITECTURE GROUP 777 - 108"' Avenue S.E., Suite 400 Bellevue, Washington 98004-5118 CAAX0015 Prepared by: DAVID EVANS AND ASSOCIATES, INC. 415 118th Avenue S.E. Bellevue, Washington 98004-6477 Revised May 1997 EXECUTIVE SUMMARY David Evans and Associates, Inc. (DEA) conducted a wetland reconnaissance of the JAG Devel- opment Property in the City of Renton, King County, Washington on October 25, 1996 (DEA, 1996). Because evidence of jurisdictional wetland conditions was found, a wetland delineation was performed in February 1997 and is documented in this report. The subject property is located at 44th Street on Lake Washington in the City of Renton, King County, Washington (Section 29, Township 24N, Range 5E W.M.). The property is approximately 65 acres consisting of five parcels: the Barbee Mill parcel (about 20 acres) on the south; the Port Quendall parcel (about 20 acres) in the middle; the Baxter Mill parcel (about 17 acres) on the north; the "Pan -abode" parcel (about 6.3 acres) located east of the main site and east of Lake Washington Boulevard, and a two -acre eastern parcel between I-405 and the southbound off -ramp. At the time of this investigation, the Barbee Mill site was fully occupied by active sawmill operations and most of Port Quendall parcel was used as a log storage yard. The Pan -abode property was occupied by industrial uses. The Baxter Mill parcel was unused except for storage of several large piles of bark mulch. Eight jurisdictional wetlands were identified on the subject property using 1987 Corps of Engineers methodology as required by the City of Renton. Each wetland has been mapped and are summarized in the table below. All on -site wetlands are in previously disturbed areas and have formed in old fill materials or in excavated areas. All would be classified as Category 3 wetlands by the City of Renton because they meet the criteria of hydrologic alteration and soils alteration (Renton, 1992). Wetland Summary Table Wetland On -site Area in City of Renton Required Buffer (Parcel location) Acres (square feet) USMS' Classification Category (width in feet) A (Quendall) 0.195 palustrine forested 3 25 (9,527) B (Quendall) 0.374 palustrine forested 3 25 (16,284) C (Quendall) 0.171 palustrine scrub -shrub/ 3 25 (7,444) emergent/open water D (Baxter) 0,080 palustrine 3 25 (3,483) scrub -shrub E (Baxter) 0.230 palustrine scrub -shrub/ 3 25 (10,027) emergentlopen water F (East) 0.150 palustrine forested 3 25 (6,528) G (East) 0.015 palustrine emergent 3 25 (661) H (Barbee) 0.141 palustrine emergent 3 25 (6.151) Total area: 1.36 (59,105) 1United States Fish and Wildlife Service (Cowardin et al., 1979). h: Woe-areabralreslivpdocslcaaarlcaurRRl51toc01105, dae Wetland Determination Report JAG Development Property i Table of Contents EXECUTIVESUMMARY........................................................................................................... i i PREFACE.......................................................................................................................................I 1. INTRODUCTION....................................................................................................................2 2. METHODS...............................................................................................................................2 2.1 Purpose..........................................................................................2 2.2 Preliminary Research.....................................................................................................2 2.3 Site Investigation.............................................................................................................5 2.4 Wetland Function Assessment.......................................................................................5 3. RESULTS.................................................................................................................................6 3.1 Site History......................................................................................................................6 3.2 Vegetation........................................................................................................................7 3.3 Soils..................................................................................................................................7 3.4 Hydrology........................................................................................................................8 3.4.1 Overall Site Hydrology.........................................................................................8 3.4.2 Stream ................ .....---------------------------- .......................... ........................................ 8 3.5 Wetland Determination..................................................................................................9 3.6 Wetland Functions........................................................................................................10 4. REGULATORY IM.PLICATIONS......................................................................................11 4.1 Wetlands........................................................................................................................11 4.2 Streams...........................................................................................................................12 S. REFERENCES.......................................................................................................................13 h. Idoc-oreatnarreslivpdocstcaax I caas001 Sitoc0005. doe Wetland Determination Report JAG Development Property ii I APPENDICES Appendix A. Corps Certification Documents i Appendix B. Plant Indicator Status Categories Appendix C. Sample Plot Data Sheets 3 Appendix D. List of Plant Species f Appendix E_ Wetland Function Assessment Rating Forms LIST OF FIGURES Figure1: Vicinity Map....................................................................................................................3 Figure 2: Existing Wetlands............................................................................................................4 LIST OF TABLES Table is Wetland Summary ........................................................................................ .....9 Table 2: Functional Assessment Summary...................................................................................9 h: l doe -a reo l na l res h wpdocs l eaas l ca= 0015 V oc 0005. doc Wetland Determination Rcport JAG Development Property iii PREFACE This report has been prepared for the use of CNA Architecture Group and the project consultants and proponents. In preparing this report David Evans and Associates, Inc. (DEA) has used the site infonmation and proposed development plans as referenced herein. Findings reported herein are based on information gathered in the field at the time of investigation, DEA's understanding of the Corps of Engineers Wetland Delineation Manual (1987), and DEA's understanding of federal, state and local regulations governing wetland and stream areas. Prior to preliminary and final design or any construction, all appropriate regulatory agencies should be contacted to verify the findings of this report, and to obtain appropriate approvals and permits. The wetland boundaries, wetland and stream classifications and recommended buffers are DEA's best professional opinion based on the circumstances and site conditions at the time of our study. The final wetland boundary determination, classification of wetlands and streams, and the required buffers and setbacks are made by the appropriate federal, state and local jurisdiction. Two of the three wetland delineators for this project are certified by the Corps of Engineers for wetland delineation. Certification documentation is included in Appendix A. h: tdoc-areatnalreslwpdocskacu4cQar00151rpt0005.doe Wetland Determination Report JAG Development Property 1. INTRODUCTION David Evans and Associates, Inc. (DEA) conducted a wetland reconnaissance of the JAG Development Property in the City of Renton, King County, Washington on October 25, 1996 (DEA, 1996). Because evidence of jurisdictional wetland conditions was found, a wetland delineation was performed in February 1997 and is documented in this report. The subject property is located at 44th Street on Lake Washington in the City of Renton, King County, Washington (Section 29, Township 24N, Range 5E W.M.) (Figure 1). The property is approximately 65 acres consisting of five parcels: the Barbee Mill parcel (about 20 acres) on the south; the Port Quendall parcel (about 20 acres) in the middle; the Baxter Mill parcel (about 17 acres) on the north; the Pan -abode parcel (about 6.3 acres) located east of the main site and Lake Washington Boulevard, and a two -acre eastern parcel between 1-405 and the southbound off - ramp (Figure 2). At the time of this investigation, the Barbee Mill site was fully occupied by active sawmill operations and most of Port Quendall parcel was used as a log storage yard. The Baxter Mill parcel was unused except for storage of several large piles of bark mulch. 2. METHODS 2.1 PURPOSE The purposes of this study were: 1) to identify, delineate, and describe any wetlands on the subject property and 2) to evaluate the wetland functions of any wetland present. Performance of these tasks involved three interrelated steps: preliminary research, site investigation, and wetlands determination. 2.2 PRELIMINARY RESEARCH Published information about local environmental conditions was reviewed for evidence of wetlands on the subject land parcel. The main information sources reviewed included: • Soil Survey of King County Area, USDA Soil Conservation Service (SCS), 1973; • National Wetland Inventory (NWI), Renton Quadrangle, 1-24,000, USDI Fish and Wildlife Service, 1988; Renton Quadrangle (1:24,000), United States Geological Survey (USGS), 1950; • Hitchcock, C.L. and A. Cronquist. 1973. Flora of the Pacific Northwest. Seattle, Washington; • Reed, Jr., P.B. 1988. National List of Plant Species that Occur in Wetlands: 1988 Northwest (Region 9). Biological Report 88 (269). U.S_ Fish and Wildlife Service, Inland Freshwater Ecology Section. St. Petersburg, Florida. [Pp.86]; • Aerial photographs, Walker and Associates, Inc. 1936, 1946, 1956, 1974, 1985, 1990, 1995; h.4doc-arealnarreshvpdocsl aarlcaax00151rpl0005.doc Wetland Determination Report JAG Development Property 2 —e SE ST SITE ST MANY- I ok fit.. I 3m K Vw- 51 tw b9lu ISM 7'ST TN ST 7 j� mm 91ST MOW w =2z POW .31ST It TH- t iL LAKE 25111 irj hASHINGTONWs lipVE Pt $1 "-MST Z, 2 KT yy 1 A _7 Arm to IF. C4 re A)~ fl: Fm F fAMM7 rft IK rm -,RNff, S7 7 STD i st AIM ME L 7mm DAvvp wv#,Ns AND AssoOArm 0 SOURCE: ThMMS BROTHERS: 1995 J.A.G. DEVELOPMENT SITE %1� Figure I Vicinity Map • EIS Framework Plan, JAG Development Planned Action, City of Renton, Huckell/ Weinman Associates, Inc. 1996; • David Evans and Associates, Inc. 1994. Wetland and Habitat Reconnaissance on the Baxter Mill Property, Renton, Washington; • Terra Associates, Inc. Wetland Delineation Report for The Baxter Mill Property, 1993; and • King County 1990. King County Sensitive Areas Map Folio. 2.3 SITE INVESTIGATION On February 19, 20, 21, and 27, 1997, DEA biologists conducted a field investigation for the presence and extent of jurisdictional wetlands on the subject property. The vegetation, soils, and hydrology of the site were examined according to the 1987 Corps of Engineers Welland Delineation Manual and subsequent Corps guidance. Twelve 0.01 acre sampling plots were established in areas of homogenous vegetation. Plant species on the site were identified (Hitchcock and Cronquist, 1973) and vegetation was considered hydrophytic (adapted to wet conditions) when over 50% of the dominant plant species had an indicator status of facultative, facultative wetland, or obligate wetland (Appendix B). In accordance with the methodology, soil samples were taken at all sampling plots as well as other points on the site, and were examined for the following indicators of hydric conditions: thick organic.layers, gleying, low soil chroma (matrix chroma 1) or mottling (matrix chroma l or 2). Hydrology of the site was evaluated through observation of surface water, soil saturation, groundwater level, and evidence of drainage patterns. Areas in active industrial use such as the Quendall parcel log storage yards and the Barbee Mill operation were not examined because hydrophytic vegetation would not have had an opportunity to develop under this level of disturbance. Wetlands were defined as areas where vegetation, soils, and hydrology reflected hydric conditions. The boundaries of the wetlands on the site were marked with orange flagging, and were surveyed and mapped by Bush, Roed, and Hitchings, Inc. The area of each wetland was calculated during survey plotting. All wetland boundaries are subject to verification by agencies having jurisdiction. iKWAY ail—ITW.l i 7 Ilia* I [U►1t�Y� I alizo I Wetlands are known to perform significant functions in the ecosystem, some of which are of im- mediate value to human society. Although these functions are complex, interrelated, and difficult to quantify, several alternative methods have been developed to assess wetland functions for spe- cific wetlands. A semi -quantitative method was used for this project (Cooke, 1996). Eight cate- gories of wetland functions are defined in this method: flood/storm water control, base flow and ground water support, erosion/shoreline protection, water quality improvement, natural biological support, overall habitat functions, specific habitat functions, and cultural/socioeconomic functions. The methodology includes a form that is used for rating wetland functions. For each wetland, a given number of points for each function based on physical characteristics such as size, nearby land h: Woc-areolnalreslwpdocslcaarlcaaro0151rpr0005. dot Wetland Determination Report JAG Development Property S uses, vegetation types and densities, and drainage patterns can be assigned and recorded on the form. The methodology states that it is not intended to be used to assign an absolute value (i.e., high, medium, low) to a function present in a wetland or to an individual wetland. Rather, it is designed to "determine the presence and relative importance of functions within the wetland" or to "rank individual wetlands by function against other wetlands in the same drainage system" (Cooke, 1996). 3. RESULTS The NWI Renton Quadrangle indicates palustrine scrub -shrub and palustrine emergent wetlands along the Lake Washington shoreline in the central part of the property. In addition, May Creek is shown as a riverine unconsolidated bottom habitat type (USDI, 1988). The King County Sensitive Areas Map Folio indicates no wetlands on the property, but shows the on -site reach of May Creek as a Class I stream (King County, 1990). A 1993 investigation of the Baxter parcel found one wetland located along the eastern on -site railroad grade (Terra Associates, 1993). The 1994 DEA site reconnaissance identified several areas of potential wetland, each of which was examined and documented during the current study. Wetland data plots documented for the current investigation are included in Appendix C and located in Figure 2. A list of plant species observed on the site is presented in Appendix D. 3.1 SITE HISTORY The southern parcel of the property has been occupied by the Barbee Mill since before 1946. According to aerial photographs, it has been relatively unchanged since 1956. May Creek was relocated between 1936 and 1946, and it presently extends along the southeastern side of the property (Figure 2). Its general channel morphology has been tnchanged since at least 1974. The central Port Quendall parcel is an active log yard immediately north of the Barbee Mill opera- tion (Figure 2). Almost the entire parcel presently experiences continued disturbance from these activities. The site was used as a creosote refinery from 1917 through 1969. Thereafter the site was used primarily as a storage area for operations occurring on the Baxter parcel. A lagoon area, pres- ently divided into adjoining north and south lagoons, appears to have been created between 1968 and 1974 (Figure 2). The shoreline in this area has been relatively undisturbed since 1985. The northernmost Baxter Mill parcel was developed in 1955 as wood treating plant and storage yard, which was in operation until 1981. Aerial photographs confirm that by 1985 the site had been aban- doned_ At the time of the investigation, the site was used only for storage of large piles of bark mulch. The Pan -abode property was developed for industrial use between 1956 and 1968 according to available aerial photographs. At the time of this investigation, the entire parcel was occupied by the Pan -abode prefabricated house -building operation. The eastern two -acre parcel was modified during the construction of I-405. Ditches and/or stream channels are clearly evident in the 1956 and in 1968 aerial photographs. The channels h: Voc-arealnalresl4pdocstcaac1caax0015Vp10005.d0c Wetland Determination Report JAG Development Property 6 were rerouted to accommodate the sonthbound off -ramp. These channels now border the parcel on the east and the north. 3.2 VEGETATION The Barbee Mill parcel and much of the Port Quendall parcel are continually disturbed by active mill operations and storage and transport of logs, and include few areas of natural vegetation. Most of the vegetated on -site area of the Barbee Mill consisted of mown lawns along May Creek and along the railroad right-of-way at the eastern parcel boundary (Data Plots 10 and 11). The inactive portions of the Port Quendall parcel, as well as the entire Baxter parcel, contained significant areas of sparse vegetation. The Baxter parcel was almost devoid of vegetation in 1985 according to aerial photographs from that year. By 1996, vegetated areas were concentrated in the vicinity of the former tank farm, the Lake Washington shoreline, and eastern margin along the railroad grade. These areas were dominated by sapling- and seedling -size black cottonwood (Populus balsamifera), red alder (Alnus rubra), and willow (Salix spp.), as well as soft rush and reed canarygrass (Phalaris arundinacea) (Data Plots 3, 12 and 13). The shoreline areas included more hydrophytic plant species including hardhack (Spiraea douglasii), common cattail (Typha latifolia), and yellow flag iris (Iris pseudacorus) (Data Plots 1 and 2). Limited areas on the eastern and western margins of the property included more mature trees (Data Plots 1, 7, and 8)_ Himalayan blackberry formed patches throughout less recently disturbed portions of the site. Small depressions supported emergent species, including soft rush (Juncus effusus), reed canarygrass, sickle-Ieaved rush (Juncusfalcatus), and bentgrass (Agroslis sp.). The small eastern parcel was occupied by forest and scrub -shrub vegetation, dominated by black cottonwood and willow trees and thick shnib-layer growth of Himalayan blackberry (Rubus discolor) and Japanese knotweed (Polygonum cuspidatum) (Data Plots 4 and 5). The eastern parcel also included a small patch of herb -layer reed canarygrass (Data Plot 6). Most of the Pan -abode parcel was paved. Vegetation had begun to re -colonize the southern end of the property, and was dominated by Himalayan blackberry, black cottonwood seedlings, and reed canarygrass. 3.3 SOILS Most of the Port Quendall and Baxter parcels are mapped by the King County Area Soil Survey (1973) as Bellingham silt loam, a poorly drained soil that is listed as hydric. The northern portion of the Baxter parcel is listed as Seattle muck, a very poorly drained organic soil that is listed as hydric. Most of the Barbee Mill parcel is mapped as Nooksack silt loam, a well -drained soil that is not listed as hydric. Much of the property had been inundated by Lake Washington prior to the artificial lowering of the Lake by about 8 feet in 1916. All of these native soils, however, have been severely disturbed by past industrial operations and largely buried under three to 13 feet of old fill material (CH2M Hill, 1978). Aerial photos show that the entire subject property was gradually cleared, graded, and filled between about 1936 and 1974. h:1 dor-arealrtalreslwpdocskaaikn4zx00! 3 trpIUOUS. doe Wetland Determination Report JAG Development Property 7 During the present investigation, soils approximating the SCS descriptions were found in only a few shoreline areas on the Port Quendall parcel (Data Plots 1 and 2). These areas may have been beyond the edge of the most recent fill deposits. The remainder of the subject property was underlain to a depth of at least 18 inches by old fill materials including: compacted gravel (Data Plots 3, 7, 8, 12, 14, and 15), decayed concrete and asphalt (Data Plot 13), and loamy sand that is probably from May Creek dredge spoils (Data Plots 4, 7, 8,10, and 11). Silt loam and silty clay loam were found only in the east parcel (Data Plots 5 and 6)_ 3.4 HYDROLOGY 3.4.1 Overall Site Hydrology Surface and shallow subsurface hydrology on the subject property involves several different processes, including 1) ponding over impervious surfaces and compacted fill, 2) interaction with the Lake Washington water level, 3) groundwater flowing onto the property from the east, and 4) past excavation of ponds and ditches. Water was observed inundating much of the Port Quendall and Baxter Mill parcels after storm events in 1996/1997. ,In extensive areas of compacted fill, water appeared to pond above these materials rather than saturating them (Data Plots 3 and 13) or to saturate them from above to a depth of only a few inches (Data Plot 12). These conditions also prevailed in the unpaved portions of the Pan -abode parcel. Several shoreline areas were saturated to the surface because of their relation to the Lake Washing- ton water level (Data Plots I and 2). Significant groundwater flows onto the subject property from the east in several locations, typically in the vicinity of the adjoining eastern railroad grades (Data Plots 7, 8, and 11). Hydrology in the eastern parcel also appears to be related to this groundwater seepage (Data Plots 4 and 6). Lastly, several on -site areas that had been artificially excavated in the past were ponded several feet deep. Several of these had been excavated as ponds or lagoons during previous industrial operations, and others appeared to have been excavated more recently in order to drain the active log storage yards. The Gypsy Creek Sub -basin Drainage is a short stretch of open channel conveying stormwater flows westward_ It is fed by a culvert that enters the subject property under a railroad grade, and discharges into a pipe that extends under the Baxter site to discharge into Lake Washington. The Barbee Ditch is an excavated drainage ditch that discharges to May Creek on the Barbee Mill Parcel. 3.4.2 Stream May Creek flows through the Barbee Mill parcel to its mouth at Lake Washington. The on -site portion was realigned into its present channel between 1936 and 1946, and is now designated as a Class 1 stream by King County. The Washington State Catalog of Streams and Salmon Utilization lists this stream as South Lake Washington Drainage 90282 in Water Resource Inventory Area #08. May Creek is known to support stocks of coho, chinook, and sockeye salmon as well as resident fish species (Williams et al., 1975). h: ldoc-arealnalreslwpdocs4caaxkaaxOO 13 krp10003.doc Wetland Determination Report JAG Development Property 8 3.5 WETLAND DETERMINATION Eight jurisdictional wetlands were identified on the subject property. They were delineated between February 19 and February 27, 1997, and were verified by the Corps during an April 8, 1997 on -site inspection. Wetland locations are shown in Figure 2 and characterized in Tables 1 and 2. All on -site wetlands are in previously disturbed areas and have formed over old fill materials or in excavated areas. All would be classified as Category 3 wetlands by the City of Renton because they meet the criteria of hydrologic alteration and soils alteration (Renton, 1992). Table 1: Wetland Summary —i i'Vetlattd (parcel,o ton)4 s�' On site Area tot Acl•es (stutire feet) '. K...I f 1 W iA ttty "' USFWS Classificgftvh i Y of-lenft' .: Calgbr�{w " 3 Xte wre dF`n iee�`' A (Quendall) 0,195 palustrine forested 3 25 ................ (8,527) .................... - ................ .......... 1 (Quendall 0.374 p alustrine forested 3 - 25 (16,284) -..........................-........---------.....-..........................--.--.--.----------............................................................ ................. . C uendall .. 0.171 palustrine scrub -shrub/ .. .-.......... 3 ---------••---•-----••--................. 25 (7,444) emergenVopen water 6($axter) 0.080 palustrine 3 25 (3,483) scrub -shrub •..........................------------------------------- ........ ............................................. E (Baxter) ............................ 0.230 palustrine scrub -shrub/ --------------------•------------------ 3 -------•---•-----------------------------. 25 (10,027) emergent/open water .................. F (East) ..•--•--•...........-..-.....-...........-..-..-.....-.....-..-..........-..............-.............--•--•-.............-................................ 0.150 palustrine forested 3 ............................... .......-. 25 (6,528) -------- ........................................... G (East) •--------...-............-.............._...-...........................................................................................I-- 0.015 palustrine emergent 3 ............................................ 25 (661) ........................................ ...............-------------•-------------- -- ---------------------------------------- ............................. N (Barbee) ....... 0,141 palustrine emergent 3 ------------------------------------------.. 25 (6,151) Total area: 1.36 (59,105) I United States Fish and Wildlife Service (Cowardin et at., 1979). Table 2: Functional Assessment Summary `Ii Flood/storm water control 15 7 7 9 9 5 11 9 6 ........ ....................... g..---.................................. ---- Base flow and round water support ------------ ........ 15 ... ............ 6 .... ....... 6 ----------- 9 ------------ -- 9 ------------ -- 7 .......... -.... 7 ................ 7 ........... - 8 ...............................................------....--.... ..................-......---•----.--- Erosion/shoreline protection 9 --------...................... 5 ................. 5 NA .......... _... NA ... ......... .... 6 ............... NA ...-•--------- NA ................ NA .... ..... •-----•............ _............ ............... -................... Water quality improvement .... --...-...........--------------- NIA NIA --••------------ NIA ------- ----- •- NIA --------------- NIA •.............. NIA ..... .......... NIA ..... I ......... NIA ................ NIA Natural biological support 36 19 23 I8 15 22 15 13 16 ......habitat...........f.u---nc----ti......on............................_..-..--------- Overall 9 ----------- 3 ................ 4.......... .....3 ...............-..-..-..------. 3 4 ......- --------3 -------- -------- 3 3.......3 ..........._ -- - ---- -- -- .... -..-.............................-_........ Specific habitat functions 15 6 7 _....................... 8 6 ,.................................... 6 6 5 _ 5 -------- --- -- - ----...... ....... ..... - CuItural/socioeconomic function 21 6 -............._...._......................................-................ 6 7 7 7 7 7 7 Overall Function Points 121 52 58 54 49 57 49 44 45 I Maximum possible score for this function. h: Idoc-area4natreslwpdocslcaaxlcaax0015Vpt0005. doc Wetland Determination Report !AG Development Property 9 Wetlands A and B are located along the lakeshore. Although they have been altered in the past, as evidenced by the immature forested vegetation, they appear to occupy gaps between the Lake Washington shore and the main on -site fill deposits that cover the rest of the property. Wetland A (Data Plot 1) is entirely forested by immature red alder with an understory of Himalayan blackberry. Hydrophytic species including yellow -flag iris, reed canarygrass, and creeping buttercup occupy the herb layer. Wetland B (Data Plot 2) includes areas of red alder forest as well as scrub -shrub areas dominated by hardhack and Pacific willow. Wetland C is a remnant of an old industrial lagoon on the Quendall Parcel. It is primarily open water, but it also supports emergent vegetation dominated by common cattail and young black cottonwood saplings overhanging the water. Wetland D is centered on an old industrial settling pond and Wetland E encompasses "Baxter Cove" (Figure 2). Both include artificial excavations, but were determined to be wetlands because vigorous communities of hydrophytic vegetation have developed. Both wetlands contain dense growth of common cattail. Wetland D also includes a shrub layer of Pacific Willow and red -osier dogwood (Cornus stolonifera). Wetland E contains an open -water component and a shrub layer of Himalayan blackberry, red -osier dogwood, and red alder saplings. Wetlands F and G are located in the small eastern parcel of the property. Wetland F (Data Plot 4) is forested by red alder, black cottonwood, and Pacific willow, with a dense understory of Japanese knotweed (Polygonum cuspidatum) and Himalayan blackberry. Wetland G (Data Plot f) is largely a monotypic patch of reed canarygrass, with shrub coverage of red -osier dogwood and Himalayan blackberry around the margins. Wetland H is located near the Barbee Mill entrance and is represented by Plot I l_ Although a small group of red alder trees overhangs part of the wetland, it is essentially an emergent wetland that is maintained as a mown lawn. Dominant species include bentgrass (Agrostis stolonifera), red fescue (Festuca rubra), and reed canarygrass. 3.6 WETLAND FUNCTIONS The on -site wetlands were evaluated for eight functions: flood/storm water control, base flow and ground water support, erosion/shoreline protection, water duality improvement, natural biological support, overall habitat functions, specific habitat functions, and cultural/socioeconomic functions. Functional assessment for each wetland is summarized in Table 2. The scores indicated are relative to a maximum potential number of "points" under this method. They can be compared with the numbers in "max." column to determine functions that have very low point scores and may thus be potentially lacking. For functions that are present, point scores can be compared to rank on -site wetland functions. Evaluation forms for each wetland identify the characteristics that influence the assessment, and are included in Appendix E. For most functions, on -site wetlands varied only slightly. This is expected, because all on -site wetlands have been altered and disturbed by industrial activities, and have developed over artificial fill deposits. Weiland F is of relatively high value for flood/storm water control because it lies in a closed depression with a constrained outlet. However, this function is lacking in Wetland E h. ldoc-0reaWafre3l wpdocslcoaxlcaas00151rp10005.doc Welland Determination Report )AG Development Property 1 Q because it is open to the Lake Washington shoreline. Wetlands C and E are the highest value on - site wetlands for "base flow and ground water support", because they are permanently flooded depressions. However, there is relatively low potential for this function on the property because of its location at the lower end of its drainage basin. Wetlands A, B, and E are the only on -site wetlands with potential value for "erosion/shoreline protection" due to their locations on the shoreline of Lake Washington. Based on available information, there is little potential for "water quality improvement" functions in any on -site wetland due to soil contamination from past uses of the site. Wetlands B and E are the highest value on -site wetlands for "natural biological support." Both of these wetlands have low proportions of invasive plant species. In addition, Wetland B has relatively high levels of "vegetation structure" and potential "organic accumulation," and Wetland E includes three classes of wetland including open water. All on -site wetlands are lacking in "overall habitat function" because they are small, with low habitat diversity and narrow to non- existent buffers that leave them open to disturbance. Wetland C is the highest value on -site wet- land for "specific habitat functions." It includes moderate levels of potential invertebrate and amphibian habitat due to its shallow inundated emergent area, and observation of nesting Canada geese was evidence of bird habitat value. All on -site wetlands have low potential value for cul- tural and socioeconomic uses according to this assessment method, because they are privately owned with access limited by pollutant hazards and ongoing industrial activity, lack commercial resources such as fish populations, are not notable for aesthetic appearance, and lack recreational and educational opportunities. Overall, all wetlands are of relatively low duality. None attain even half of the maximum points available. 4. REGULATORY IMPLICATIONS 4.1 WETLANDS Several federal, state and local regulations apply to development proposals in and near wetlands. Agencies having jurisdiction overdevelopment activities that affect wetlands may include, but may not be limited to, the City of Renton, the Washington State Department of Ecology (WDOE), Washington State Department of Fish and Wildlife {WDFW), and the U.S. Army Corps of Engi- E veers (Corps). The City of Renton has guidelines for development in and near wetlands and for t mitigation for permitted wetland impacts resulting from development. The WDOE has review and approval authority for many Federal, State, and local permits. In addition, the WDFW administers the State Hydraulic Code, which is intended to protect fish life and its supporting habitat. The Corps regulates the discharge of fill material into jurisdictional wetlands. This determination report conducted by DEA is subject to verification and approval by these agencies. Detailed site design prior to verification by agencies is not advised. Pursuant to the Clean Water Act, and through the Section 404 permitting process, the Corps has been given the responsibility and authority to regulate the discharge of dredged and fill materials into waters of the United States including wetlands. Currently, Nationwide Permit 26 under Sec- tion 404 allows filling less than 0.33 acres of wetlands that are not within 100 feet of a stream having a channel over two feet wide. When filling such wetlands, the Corps must be notified within h,-ldoc-areaWaireslwoocskaaxkaaxOOI51rpr0005. doc Wetland Determination Report JAG Development Property 1 1 30 days after construction. Under Washington State regional conditions, fills between 0.33 acres and 2.0 acres, located over 100 feet from any stream channel over two feet wide, may be filled subject to a "pre -construction notification" involving submission of a site plan and wetland mitiga- tion plan. Any wetland fills totaling more than two acres, or any filling of wetlands within 100 feet of a stream channel over two feet wide, requires an individual permit. The individual permit proc- ess requires a full project alternatives analysis, and the project is typically modified to reduce im- pact. For all wetland filling totaling one acre or more, a separate water quality certification is required by the WDOE. The State Environmental Protection Act (SEPA) is implemented by local agencies and provides a process to analyze the environmental impacts of development. During SEPA environmental re- view, various agencies have the opportunity to review and comment on proposal. The City of Ren- ton will act as the lead SEPA agency for this project. City of Renton regulations define development parameters in and around wetlands, streams, steep slopes, shorelines, and other sensitive areas. The City reviews all development proposals and im- plements the appropriate restrictions outlined in the regulations. The on -site wetlands fall within the City classifications and require buffers as shown in Table 2. Renton regulations allow for fill- ing of some wetlands, but requires mitigation in the form of wetland creation or enhancement. 4.2 STREAMS May Creels is a Class 1 stream requiring a 100-foot buffer (50 feet along each bank) in the City of Renton. May Creels is also considered a "shoreline of the state" and falls within the Washington. Shorelines Management Act. h: l doc-area tnalreslwptocslcawcicaas00l51rp$0005. doc Wetland Determination Report JAG Development Property 12 S. REFERENCES Adamus, Paul R., E.J. Clarian Jr., D.R. Smith, R.E. Young, and ARA Inc., 1987. Washington, D.C., U.S. Army Corps of Engineers Environmental Laboratory. CH2M Hill, 1978, Preliminary Geotechnical Investigation, Port Quendall Development, Renton, Washington. Project S 12212.B0. Memorandum to Mr. Jeff Layton dated December 20, 1978. Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe, 1979. Classification of Wetlands and Deepwater Habitats of the United States. Office of Biological Services, Fish and Wildlife Service, U.S. Dept, of the Interior, FWS/OBS-79/31. David Evans and Associates (DEA), 1996. Wetland Reconnaissance on the JAG Development Property. Project CAAX0015, Memorandum to Mr. Jim Spitze dated November 4, 1996. Bellevue, Washington. Environmental Laboratory, 1987. Corps of Engineers Wetlands Delineation Manual. Technical Report Y-87-1, U.S. Army Engineer Waterways Experiment Station, Vicksburg, Mississippi. Hitchcock, C.L., and A. Cronquist, 1973_ Flora of the Pacific Northwest. University of Washington Press, Seattle, Washington. King County, 1990. King County Sensitive Areas Map Folio Reed, P.B. Jr., 1988_ National List of Plant Species That Occur in Wetlands: 1988 Northwest (Region 9). Biological report 88 (26.9), U.S. Fish and Wildlife Service, Inland Freshwater Ecology Section, St. Petersburg, Florida. pp. 86. Reppert, Richard T., Wayne Sigleo, Eugene Stal"v, Larry Messman, and Caldwell Myers, 1979. Wetland Values - Concepts and Methods for Wetlands Evaluation. Fort Belvoir, Virginia: U.S. Army Corps of Engineers Water Resources Institute. Terra Associates, 1993. Wetland Delineation Report for The Baxter Mill Property. Seattle, Washington. Thomas Brothers, 1995. The Thomas Guide - King, Pierce, and Snohomish Counties Street Guide and Directory. U.S.D.A. Soil Conservation Service, 1973. Soil Survey King County Area, Washington, D.C., U.S. Government Printing Office. U.S.D.I. Fish and Wildlife Service, 1987. National Wetlands Inventory Renton Quadrangle. U.S.G.S. 1950. Renton Quadrangle Map. h.,Woc-areal natresl wpdacsicaazicaax00151rpt0005.doc Wetland Determination Report JAG Development Property 13 Williams, RW, R.M. Laramie, and J.J. Ames 1975. A Catalog of Washington Streams and Salmon Utilization - Volume 1, Puget Sound. Washington Department of Fisheries. h: ldoc-areaWatrerlwpdoesL-oaxlcaan001 StrptOOOJ.doc Wetland Determination Report JAG Development Property 14 APPENDICES APPENDIX A CORPS CERTIFICATION DOCUMENTS DEPARTMENT OF THE ARMY SEATTLE DISTRICT. CORPS OF ENGINEERS P.O. Box 3755 SEATTLE. WASHINGTON 98i2A-ZZ33 Mmy TO NTEMTIOM OF U. S. ARMY CORPS OF ENGINEERS CERTIFIES' THAT MR. JEFFREY MEYER has successfully demonstrated to the U.S. Army Corps of Engineers (Corps), Seattle District, sufficient understanding of, and the capability to perform satisfactory wetland delineations consistent with, the Corps 1987 Wetland Delineation Manual and supplemental guidance. This verifies that wetland delineations performed by the certified wetland delineator named above will rgceive expedited consideration and acceptance by the certifying district, for purposes of the Carps' final determination of wetland jurisdiction pursuant to Section 404 of the Clean Water Act. THOMAS F. MUELLER Date Chief, Regulatory Branch Expires March 1994 Seattle District *This is a provisional certification for the purposes of the demonstration phase of the Corps wetland Delineator Certification Program and ►rill not be honored after March 1994. DEPARTMENT OF THE ARMY SEATTLE DISTRICT, CORPS OF ENGINEERS P.O. BOX 37755 SEATTLE, WASHINGTON 9AIZ4-ZZ53 "PL T To •TT[NTF0m DF Regulatory Branch JEFFREY MEYER DAVID EVANS & ASSOCIATES, INC 415 118TH AVENUE S.E. BELLEVUE, WA 98005-3553 Dear Participant: MAR 1 8 1994 MAR 21 1994 The purpose of this letter is to inform you that your provisional certification by the Seattle District, as part of the Corps' Wetland Delineator Certification- Program (WDCP), has been extended. The Corps initially anticipated implementing the WDCP nationwide in March 1994 at which time this provisional certification would have expired. Since that timeframe will not be met. your provisional certification will remain valid until a final WDCP is adopted, This provisional certification may then be renewed, revised, or replaced, depending on the final WDCP. You will be notified of what action you must take, if any. to remain a certified wetland delineator in Seattle District once the final WDCP is authorized. I would like to take this opportunity to thank you for your participation in the demonstration phase of the Corp's WDCP in the Seattle District. Your willingness to be involved in the development of the program is appreciated. Sincerely. Deborah J. Kn b Environmental Analyst w U.S. ARMY CORPS OF ENGINEERS CERTIFIES' THAT MR. JOHN MACLIN has successfully demonstrated to the U.S. Army Corps of Engineers (Corps), Seattle District, sufficient understanding of, and the capability to perform satisfactory wetland delineations consistent with, the Corps 1987 Wetland Delineation Manual and supplemental guidance. This verifies that wetland delineations performed by the certified wetland delineator named above will receive expedited consideration and acceptance by the certifying district, for purposes of the Corps` final determination of wetland jurisdiction pursuant to Section 404 of the Clean Water Act. I THOMA F. MUBLLER Chie Regulatory S ch Seattle District I Date This is a provisional certification for the purposes of the demonstration phase of the Corps Wetland Delineator Certification Program (WDCP) and will be honored until the final WDCP is implemented nationally. APPENDIX B PLANT INDICATOR STATUS CATEGORIES VEGETATION CLASSIFICATION SYSTEM Indicator Status of Plant definition Obligate Wetland (OBI.) Occurs almost always (estimated probability >99%) in wetlands under natural conditions, but may also occur rarely (estimated probability <1%) in non - wetlands Facultative Wetland Usually occur (estimated probability 67% to 99%) in (FACW) wetlands, but may also occur (estimated probability 1 % to 33%) in non -wetlands. Facultative (FAC) Plants with similar likelihood (estimated probability 33% to 67%) of occurring in wetlands or non - wetlands. Facultative Upland (FACU) Usually occur (estimated probability 67% to 99%) in non -wetlands, but also occur (estimated probability 1 % to 33%) in wetlands. Obligate Upland (UPL) Occurs almost always (estimated probability >99%) in non -wetlands under natural conditions. Data source: Reed, 1988. APPENDIX C SAMPLE PLOT DATA SHEETS Plot 1 Project Name: Field Investkator(s): Applicant/Owner. County: David Evans and Associates, Inc - INTERMEDIATE -LEVEL ONSITE DETERMINATION DATA SHEET JAG Development Site Job Number. CAAX0015 BCFIJDM Sample Plot: i CNA Group Dale: 212"7 King Stale Washington SOILS SeneslPhase: Nooksack all Loam Is the soil on the hydric soils list? No Sod Profile: 0-1- 10 YR 712 loam wl 10 YR 414 mottles 1-51 10 YR"loamy sand wl 10 YR 414 mottles 5-18- 5 GY 411 loamy send Other hydne sod indicators: VEGETATION Tree Layer Indicator Cover Mid- Herbaceous Layer Indicator Cover Mid - Scientific Name Status Class Point Scientific Name Status Class Point t Alnus rubra FAC 7 980 1 Irispseedaeorur OBL 4 38.0 2 2 Ranunculus rcpens FACW 2 10.5 3 3 Phalarisarundinaeea FACW 3 20.5 ' 4 4 5 S 6 ti Sum: 98.0 7 Shrub Layer 8 1 Rrrbro discolor FACU 5 53.0 Sum: 69.0 2 3 Percentage of Dominant Species 4 That are OBL,FACW, andlorFAC: 75.09E 5 Sum: 63.0 HYDROLOGY Surface inundated? No Surface water depth: Soil saturated? Yes Depth of free standing water in test pit? 10. Other field evidence of surface inundation or soil saturation: WETLAND DETERMINATION Is the hydrophytic vegetation criterion met? Yes Is the hydric soil criterion met? Yes Is the spec fic hydrology criterion met? Yes Is this plot located in a weltand? Yes Rationale: (in Welland A) vrzvt �...,„ off rAsrrrxis Plot 2 David Evans and Associates, Inc - INTERMEDIATE -LEVEL ONSITE DETERMINATION DATA SHEET Project Name: JAG Development Sife Job Number. CAAX0015 Field Investigalor(s): BCFfJDM Sample Plot: 2 AppllcanVOwner. CNA Group Date: 220/97 County: King Stale Washington Series/Phase: Sod Profile: SOILS Nooksack Silt Loam Is the soil on the hydric soils list? No 0-18+' 10 YR 211 muck Other hydric soil indicators: f i VEGETATION i Tree Layer Indicator Cover Mid- Herbaceous Layer Indicator Cover Mid - Scientific Name Status Class Point Scientific Name Status Class Point 1 1 Typha fatifolia OBL 5 63.0 ' 2 2 3 3 4 4 ! 5 5 i 6 6 Sum: 7 Shrub Layer a i f Sphwadouglasii FACW 3 20,5 Sum: 63,0 2 Sa1ix lasimdry FACW 5 63.0 ' 3 Percentage of Dominant Species 4 That are OBUACW, andforFAC: 100.0% 5 Sum: 83.5 i HYDROLOGY Surface inundated? Yes Surface water depth: 1' Soll saturated? Yes Depth of free standing water in lest pit? 0' Other field evldenoe of sudam inundation or soil saturalion: i WETLAND DETERMINATION Is the hydrophytic vegetation cnterian met? Yes Is the hydric sod criterion met? Yes Is the specific hydrology criterion met? Yes Is this plot located in a wetland? Yes I Rationale: (!rr Wetland B) i "247 OATASNTJQS fc�.w .wr Plds 1-1 Plot 3 David Evans and Associates, Inc. INTERMEDIATE -LEVEL ONSITE DETERMINATION DATA SHEET Project Name: JAG Development Site Job Number CAAX0015 Field Investigatorjs): BCF/JDM Sample Plot: 3 ApphcanuOwner. CNA Group Dale: 22"7 County. King State Washington SOILS Sedes/Phase: Belfingharn Siff Loam Is the soil on the hydric soils Est? Yes l iSoil Profile: Compacted gravelly Till i` f 4 Other hydric soft indicators: P VEGETATION i Tree Layer Indicator Cover Mid- Herbaceous layer indicator Cover Mid - Scientific Name Status Class Point Scieitifie Name Status Class Point t Pop dar bats=ifera FAC 6 85.5 1 Anew effuna FACW 6 85.5 ` 2 2 3 3 d 4 5 5 i fi 6 Sum: 55.5 7 Shrub Layer 8 t i Sum: 85.5 2 3 Percentage of Dominant Species d That are OBL,FACW. andlorFAC: f 00.0% i i 5 i Sum: 4 k HYDROLOGY i Surface inundated? Yes Surface water depth: 6' Sod saturated? No Depth of tree standing water in lest pit? 1 Other field evidence of surface inundation or soil saturation: i WETLAND DETERMINATION Is the hydrophytic vegetation criterion met? Yes Is the hydric soil criterion met? Assumed Is the specific hydrology criterion met? Yes Is this plot loraied in a wetland? no Rationale: Nof furisdkV0nal wellend as per on-sde inspection by Carps 4!&97 Yif/V7 G4rAWffA S Plot 4 ! David Evans and Associates, Inc. C INTERMEDIATE -LEVEL ONSITE DETERMINATION DATA SHEET I Project Name: JAG Development Site Job Number. CAAK0015 Field Investigator(s): BCF/JDM Sample P1oL 4 € Applicant/Owner: CNA Group Date: 2/2G-97 County. King Slate Washington I SOILS i SeriestPhase: BeO Ingham Silt Loam Is the soil on the hydric soils list? Yes i Soil Profile: 0 f" 10 YR 32 A loam } 6-18+' 2.5 Y 412 loamy sand w! 10 Yid 414 mottles l ! Other hydric soil indiralors: VEGETATION Tree Layer Indicator Cover Mid- Herbaceous Layer Indicator Cover Mid - Scientific Name Status Class Paint Scientific Name Status Class Pant I Alma rubra FAG 4 38.0 1 2 PopuRc balsamifera T FAC �4 2 3 Salix ldskuwd a FACW 38.0 3 4 4 5 5 6 6 Sum: 76LO 7 Shrub Layer 8 I Palygonum cwpidarunr FACU 6 85.5 Sum: 2 Rubus discolor FACU 4 36.0 ' 3 Percentage of Dominant Species 4 That are OBL,FACW, andlorFAC: 50.0% i 5 Sum: 12,15 HYDROLOGY i Surface inundated? No Surface water depth: Soil saturated? 9 Yes Depth of tree standing water in lest pit? 10, Other field evidence of surface inundation or soil saturation: wafer -stained leaves ' sediment deposits WETLAND DETERMINATION Is the hydmphytic vegetation criterion met? No Is the hydric soil criterion met? Yes Is the specific hydrology aslerion met? Yes Is this plot located in a wetland? Yes t2atlonale: (fn Welland F) ! Non-hydrophylic vegetation is esleblished among kxUcetors of larPq-duration hydrology. srrasr pnrwyrtans wor. r-r Plot 5 David Evans and Associates, Inc. INTERMEDIATE -LEVEL ONSITE DETERMINATION DATA SHEET Project Name: JAG Development Site Job Number. CAAX0015 Field lmrestigator(s): _ BCF/JDM Sample Plot: S _ ? Appticani/Owner. _ CNA Group Data_ 2/20/97 f County: King Slate Washington SOILS Series/Phase: Bellingham Sit! Loam 1s the soil on the hydric soils list? Yes Sod Profile: 0-16, 10 YR 32 sift loam i l + Other hydric soil indicators: 1 VEGETATION Tree Layer Indicator Cover Mid- Herbaceous Layer Indicator Cover Mid - Scientific Name Status Class' Point Scientific Name Status Class Point 1 Popefar babantiJera FAC 5 63.0 1 2 2 i 3 3 4 4 c 6 6 Sum: 63.0 7 Shrub Layer a E 7 Ruburdisco/ar FACU 7 98.0 Sum: 2 3 Percentage of Dominant Species 4 That are 08L,FACW, andiorFAC: 50.0% i 5 Sum: 98.0 I i HYDROLOGY I Surface inundated? No Surface water depth: Sod saturated? Ab Depth of free standing water in test pit? I Qther field evidence of surface inundation or soil saturation: WETLAND DETERMINATION Is the hydrophylic vegetation criterion met? Na 13 the hydric sal criterion met? NO Is the specific hydrology criterion met? No Is this plot located in a wetland? No Rationale: (North of Wefland F) 2navr Iw Prop rf 4I Plot 6 David Evans and Associates, Inc. INTERMEDIATE -LEVEL ONSITE DETERMINATION DATA SHEET Project Name: JAG Development Site Job Number. CAAX0015 Field Investigatols): i ECF/JDM Sample Plol: 6 AppliCe 11Ownef: CNA Group Date: 212"7 County: King State Washington i SOILS Series/Phase: Belftham Sift Loam is the soil on the hydric soils list? Yes Soil Profile: (M. 10 YR 312 sift loam 8-18" 5 Y W sill clay loam vdmottles �4 Other hydric soil indicators: VEGETATION i Tree Layer Indicator Cover Mid- Herbaceous Layer Indicator Cover Mid - Scientific Name Status Class Point Scientific Name Status Class Point t Phalarrs arwrdinacea FACW 6 85.5 ' 2 2 3 3 4 4 5 5 --- B ti Sum: 7 - Staub Layer 8 1 camas srolonifera FACW 3 20.5 i Sum: 85.5 2 Rubus discolor FACU 4 38.0 3 Percentage of Dominant Species i 4 That are OBL,FACW, andlorFAC: 66.7% 5 Sum: 58.5 HYDROLOGY Surface inundated? No Surface water depth: Soil saturated? Yes Depth of free standing water in lest pit? 14" Other field evidence of surface inundation or sail saturation: WETLAND DETERMINATION Is the hydrophytic vegetation criterion met? Yes Is the hydric soil criterion met? Yes Is the specific hydro" criterion met? Yes Is this plat located in a wetland? Yes Ralionale: (In Wetland G) srsxnr o47Asxrxus .c......»r Pp*ft 14 Plot T David Evans and Associates, Inc. INTERMEDIATE -LEVEL ONSITE DETERMINATION DATA SHEET Project Name: JAG Development Site Job Number. CAAX0015 Field Invesfigator(s): BCMlJDM Sample Plot 7 Applic antlOwner CIVA Group Date: 212W7 County: Ming StateWashington SOILS Series/Phase: Seattle Muck Is the soil on the hydric soils list? Yes Soil Profile: 0-8+' 5 GY 4/1 gravelly sand w/ 10 YR 314 mottles Other hydric soil Indicators: I VEGETATION i Tree Layer indicator Cover Mid- Herbaceous Layer Indicator Cover Mid - scientific Name status Class Point Scientific Name Status Class Point 1 Alma rubra FAC 3 20.5 1 hmcm effww FACW 3 20.5 ` 2 PopvhQ bal=mifera FAC 4 38.0 2 3 3 4 4 � 5 g 6 i Sum. 56.5 7 Shrub Layer 8 t Wir iWkniFa FACW 4 38.0 Sum: 20.5 2 Rubra dfreolar FACU 4 38.0 3 Percentage of Dominant Species 4 That are 0SUACK andlorFAC: 80.0% 5 Sum: 76.0 HYDROLOGY Surface inundated? Yes Surface water depth: Sall saturated? Yes Depth of Mm standing water In test pit? Other field evidence of surface inundation or sal saturation: i WETLAND DETERMINATION Is the hydrophytic vegetation criterion met? Yes Is the hydric soil criterion met? Yes Is the specific hydrology criterion met? Yes Is this plot located In a welland? no i Nationale: Not jurisdkiional wetland as per Corps on -site inspection 44W97 i 44IAT WITASNfXTS v.wr.i Prom H I Plot 8 t{ David Evans and Associates, Inc. f INTERMEDIATE -LEVEL ONSITE DETERMINATION DATA SHEET Proiect Name: _ JAG Pe_veopmenl Site Job Number CAAX0015 Field Investigator(s): BCF/JDM Sample Plot B ApplicantlOwner. CNA Group Date: 212Oi97 County: ling state Washington SOILS ° Series/Phase. Seattle Muck Is the soil on the hydric soils list? Yes i Soil Profile: GLIB' 2.5Y40loamysand Other hydric soil indicators: 1 VEGETATION Tree Layer i` Indicator Cover Mid- Herbaceous Layer Indicator Cover Mid - Scientific Name Status Class Point Scientific Name Status Class Point I t Popvlrubalatcnifcrn FAC 2 10.5 1 lunetycffitnu FACW 6 85.5 ' 2 Alnus rubra FAC 2 10.5 2 Piudarisarwrdinacra FACW 2 10,5 3 3 _. 4 4 5 5 fi r 6 •• l Sum: 21.0 7 Shrub Layer B f Rubra discolor FACIJ f 3.0 Sum: 960 2 3 Percentage of Dominant Species 4 _ That are OBL,FACW, andloWAC: 75.0% 5 Sum: 3.0 HYDROLOGY Surface inundated? Yes Surface water depth: Soil saturated? Yes Depth of free standing water in lest pit? 0' Other field evidence of surface Inundation or sod saturation: WETLAND DETERMINATION Is the hydrophytic vegetation criterion met? Yes Is ft hydric sail criterion met? Yes Is the specific hydrology criterion met? Yes Is this plot located in a wetland? no Rationale: not jurisdictional wetland as per Corps on-sde inspection 4WI frt rA� a+trAsrrrxis Plot 10 Projed Name: Field Investigator(s): ApplicantfOwner County: David Evans and Associates. Inc. INTERMEDIATE -LEVEL ONSITE DETERMINATION DATA SHEET JAG Development Site Job Number: CAAX0015 JDhi/JCM Sample Plot: CNA Group Date: King State Washington SOILS 10 2121197 SeriesfPhase: Nooksack Sift Loam Is the soil on the hydric soils list? No Soil Profile: 0-16+' YR 3�2 gravelly loamy sand wf faint 10 YR mottles below 12' Other hydric soil indicators: VEGETATION Tree Layer Indicator Cover Mid- Herbaceous Layer indicator Cover Mid - Scientific Name Status Class Point Scientific Name Status Class Point 1 Alnur rubra FAC 1 30 1 Fe3iuca rubra FAC 3 20.5 2 2 Agrosris srotorrrfem FAC 4 36.0 ' 3 3 Hypochoeris radicaro FACU 2 10.5 4 4 Phalara arurrdinacta FACW 4 38.0 ' 5 5 Sum: 3.0 7 Shrub Layer 8 R 1 Sum: 107,0 3 Percentage of Dominant Species 4 That are OSUACK andlorFAC: f00.0% 5 Sum: KYDROLOGY Surface inundated? No Surface water depth: Soil saturated? No Depth of free standing water in test pit? I Other field evidence of surface inundation of Solt saturation: WETLAND DETERMINATION Is the hydrophytic vegetation criterion met? Yes Is the hydric soil criterion met? Yes Is the specific hydrology criterion met? No Is this plant wmnxm*y a wetland? No Rationate: (Near Barbee entrance) ? No saturation dudnq very wet recent weather. f+f2Nr .....,. parasrrt xr.s KM�.fM Prom T61 It Plot 11 David Evans and Associates, Inc. INTERMEDIATE -LEVEL ONSITE DETERMINATION DATA SHEET Project Name: JAG Development Site Job Number. CAAx0015 Field lnvestigator(s): JDWJCM Sample Plot 11 Applicant/Owner: CNA Group Date: 2/21/97 County: King State Washingfon SOILS Series/Phase: Nooksack Sift Loam Is the sod on the hydric soils list? No Soil Profile: 0-6' 10 YR 32 gravefty loamy sand 6-18' 10 YR 3/1 grayefly loamy sand w! faint 10 YR 412 mottles Other hydric soil indicators: i VEGETATION Tree Layer Indicator Cover Mid- Herbaceous Layer indicator Cover Mid - Scientific Name Status Class i Point Scientific Name Status Class Point 1 A1nus rubra FAC 4 38.0 t Agrosrir srolnnifera FAC 4 38.0 ' 2 2 FE.viuca cobra FAC 4 38.0 3 3 Phalaris arundlnacea FACVV 4 38.0 ' 4 4 5 5 6 6 Sum: 38.0 7 Shrub Layer t3 1 Sum: 114.0 i 2 3 Percentage of Dominant Species 4 That are OBL,FACW, andiorFAC: 100.0% 5 Sum: HYDROLOGY Surface inundated? No Surface water depth: Soil saturated? Yes Depth of free standing water in test pit? Q' Other field evidence of surface inundation or soil saturation: I WETLAND DETERMINATION Is the hydrophytic vegetation criterion met? Yes Is the hydric sal criterion met? Yes Is the specft hydrology criterion met? - Yes Is this plant community, a wetland? Yes Rationale: (Near Alot 10) xrzvr ._.. DArAs►rrMs P10 It 12 David Evans and Associates, Inc. INTERMEDIATE -LEVEL ONSITE DETERMINATION DATA SHEET Project Name: JAG Develbpment Site Job Number CAAX0015 Field Investigator(s): JDM/JCM Sample Plot 12 Applicant/Owner. CNA Group Dale: 227i97 County: King State Washington REQ1�1 SerieslPhase: Seattle Muck Is the soil on the hyddc soils list? Yes Sod Profile: 0-1' 10 YR 212 sand loam 2-8. S5 BG sand foam W 2.5 Y"mottles 8-12' Hardpan U Other hydric soil indicators; VEGETATION Tree Layer indicator Cover Mid- Herbaceous Layer Indicator Covet Mid - Scientific Name Status Class Point Scientific Name Status Class Point t Popalus flarjam feria FAG 7 99.0 1 jWWW cffusus FACW 2 f a s ' 2 2 Nafew ferrvrur FAC 1 3.0 ' 3 3 4 4 5 5 � 6 6 Sum: 98.0 7 Shrub Layer e 1 Sum: 13.5 z 3 Percentage of Daninanl Species 4 That are OBL,FACW, andtorFAC: 100.0% 5 Sum: HYDROLOGY Surface inundated? No Surface water depth: Soil saturated? Yes Depth of free standing water in test pit? 5' Other field evidence of surface inundation or soil saturation: WETLAND DETERMINATION Is the hydrophytic vegetation criterion met? Yes Is the hydric sod criterion met? Yes Is the specific hydrology criterion met? Yes Is this plant community a welland? no Rationale: not lurisddional YmUend as per Corps inspection 4AW7 I i #/? PAT 13A TASNT_XLS warnw Fmft 12•03 Plat 93 David Evans and Associates, Inc. INTERMEDIATE -LEVEL ONSITE DETERMINATION DATA SHEET Project Name: JAG Development Site Job Number CAAX0015 Field Invesligalogs]: JDWJCM Sample PloL- 13 AppfiCanllOvmer: CNA Gmup Date: 2127R7 County: King slate Washington SerieslPhase: Seatfle Muck SOILS Is the soil on the hydric soils fist? Yes Soil Profile: 4 Old decayed concrete } Other hydric soft Indicators: VEGETATION Tree Layer Indicator Cover Mid- Herbaceous Layer Indicator Cover Mid - Scientific Name Status Class Point Scientific Name Status Class Point 1 Poputw balsamifera FAC 1 3.0 1 luncur effiow FACW 1 3.0 ' 2 2 Halts lamwta FAC 1 3.0 ' i 3 3 Agrosris sfolonrfera FAC 1 3.0 ' 4 4 5 5 6 6 _ T Sum: 3.0 7 E Shrub Layer a 1 Sum: 9.0 a 2 3 Percentage of Dominant Species 4 Thai are OBL,FACW, arrdlorFAC: 100.0% 5 Sum: HYDROLOGY ! Surface inundated? Approx. 20% of plot Surface water depth: i" Soft saturated? Depth of Tree standing water in test pit? Other field evidence of surface inundation or soil saturation: WETLAND DETERMINATION Is the hydrvphytic vegetation criterion met? Yes Is the hydric soli criterion met? No Is the speeft hydrology Criterion met? No Is this plant community a wetland? No Rationale: Waler patched on impervbus surface. Plants growing in cracks, typicaf of site- •nr�r ' VA rAsr+r_¢S A....� PW& r?-r] APPENDIX D LIST OF PLANT SPECIES Species Acer macrophyllum Agropyron repens Agrostis tenuis Alnus rubra Carex obnupta Cirsium arvense Comus stolonifera Dactylis glomerata Epilobium ciliatum Iris pseudacorus Juncus effusus Phalarls arundinacea Polygonum cuspidatum PolysUchum muniturn Populus balsamifera Pteridium aquilinum Ranunculus repens Rubus discolor Rubus lacinatus Rubus spectabilis Rubus vitifolius Rumex cnspus Salix lasiandra Sambucus racemosa Spiraea douglasii Tolmeia menziesii Typha latifolia List of Plant Species Common Name big leaf maple quackgrass colonial bentgrass red alder Slough sedge Canada thistle red -osier dogwood orchardgrass hairy willow -herb yellow flag iris soft rush reed canarygrass Japanese knotweed sword fern black cottonwood bracken fern creeping buttercup Himalayan blackberry evergreen blackberry salmonberry Pacific blackberry curly dock Pacific willow red elderberry hardhack pig -a -back plant common cattail Indicator Status FACU FACU UPL FAG OBL FACU FACW FACU FACW- OBL FACW FACW FACU UPL FAC FACU FACW FACU FACU FAC FACW FACW FACW+ FACU FACW FAC QBL APPENDIX E WETLAND FUNCTION ASSESSMENT RATING FORMS Wetland and Buffer Functions and Serni-quantitative Performance Assessment Wand # Staff �P Date 9' +cation S. T R Criteria Function Group 1 1 pt Gmup 2 2 pts Group 3 3 pty Flood/ 2� size < 5 acres st m 5-10 acres ,_.-, stre > 10 acres a headwalaM �0�'na�' Storm Water <` % o -3a rarescea cover X > 3p� ed oovor Control owes — semi-oonstrained outlet — advertbammed outlet located in lower 1/3 of lime drainage locled In middle 1 r3 of the drainage — tooted In upper 1 A of isms drainage points 7 (max 15) Base Flowf stze <5 acres — sire 5-10 acres — size > 10 acres rfveitoortakashmw%Wid mid-slopedwedand deer+gssfons,headwapambogs,11= ground Water �[ focawd In lower 1!3 of the drainage located In f kUe 1/3 of the drainage _ lowedhupMjaofthedrainage Support _vaWora4 boded or saturated seasonally or seml-pennanendy perm&w* boded or summed, or flooded or satiated i nhetmMndy exposed ?� no IOw-sensitive tlstm populations _ low flow-sensfte lists populations . — high low -se nsit3ve populations t -6 on -site or.downstmarn on -site or downstream MAIguous with sde In Ng* (max 15) permeable saata r o s i o n I — sparse grassoherbs or no veg alo g — sparse *oo0 or veg along OHM X dense wood or veg along OfiWM h o r e l i OHWM _ vvedaM extends 30 - 50 m tmm -1n e _ wetand wdends < 30 m from OHWM — wetland extends > 200 m from Protection OHWM r rrWaratetydevelopedshorWwor OHWM Y highly developed shoreline or sub atch ment — undeveloped shoreline or pom ant subeat rent y (max 9) ✓hater Quality — r'aPlo low MrouM site — rr+oderate Aawthrough site slow fiowM(Mi,7h site < 5o % veg cover 50 - 80 % cover > Sp % veg cover Improvement — upstream in b , km wetland is — s sass of basin upsnam from > 50% of basin upstream from urMveloped wetland is developed VMdwd is developed polm hoids < 25 % overhand nmon — holds 25.50 % overland rvnof _ holds > 50 % overland runoff (max 12) VA = Not App(e, NI1= No information availatfal i &e ,ominant Vegetation: A b Rv -F le P5 7N P R Wildlife: Wetland and Buffer Functions and Semi -quantitative Performance Assessment Naturals stze <s ages B i o l o i c a l ' ag tend. bw veg suvclt rq 9 seasonal "tam water Support - onehabtAW PAS POW PEM PSS F9 EST low plant diversity (e 6 species) poirgs 17 (max 30 Overall H.abltat Functio s points (ma)(9) Specific Habitat Functions points 6., (max Is) Cultural/ Socioeco- nomic points (Max 21) Notes: > 50 % Invasive species low primary podum" lour orgaft som miutatioc+ low organic export few habitat leatures 3 Mftsvery ditsturbea Waled yvm upE habitats sue < 5 aces �! low habitat aversky low sanctuaryor room low iwartebm habitat lour arltpintilan habitat low full habitat low mammal habitat low bird habitat x low educational oppalunMes �[ low aesthetic value ' lads commercial fisheries. agrkx#)jre, renewable resvurCeS i lacks historical of archeolOgiCal resources lads passive and active recreational opportunities privately owned rtat near open space sire 5 -10 acres �. 2level veg permanent surf`" water two habitat Ww PAB POW PEM PSS PFO EST moderate plant diversity (7-15 spades? 10 to 50 %Was" species moderate primary productively moderate organic aocumulation T, some habelat teatu es butters sigrWy disturbed . partially connected to upland habUM size 5-10 acres moderate habitat diversity moderate sanctuary or refuge moderate it erlebrate habitat ,Z moderate amphi5iarl habitat moderate Iish habitat moderate mammal habitat moderate bind hart moderate educational Opportunities moderam /aesthetic value moderate commercial fisheries, agriculture, rerKrwable re UMSS historical or anchtKOoglcal site some paW" and active reaeaidanai opporax WS privately t WXxt. same MA& some connec lon to open space size > 10 acr" -i hkjh veg stlixxtag open Walter habta llYPOS ols ti senmriler PAB ROW PBAPSS PFp E♦5T high Plant diversity. (> 15 species) h gtheprkrWy acies produaS,rely _aC — _ buflersnO1 weq conned to upland hat. rr _. stm > 10 acres high habKat diMr,;ty, high sarrduary or mkve . high Invertebrate haf iW high amphtnn habitat high 6sh habtat high mammal habdat — high bird Habitat high educational oppoMmities high aesthetic value T high commercial fisherim, agricvfiure, renewable resources Important historical or ar heologtcal site many passhoe and alive recre)atlanal opporW fits r. unrestricted public access clinxhyconneaed to open space Wetland and Buffer Functions and Semi -quantitative Performance Assessment !tland Staff 3 Date /3 ? 21 2fN nsr "ration S T R Criteria Function Group 1 1 pt Group 2 2 pts Group 3 3 pts Flood/ size < 5 acres size 5-10 acres _ SPZe > 10 acres Storm Water (, �-` `� or ial�share vvetlarnd _ mld-roped wetland depressk)(M hea jwaMM bMAats _ < 10 % lorested cover _ 10 - 30 % wrested a wff > 30 % io %M covet Control tC reed outer _ semi Con strained outlet W cukeMbermed outlet located in lower iia of the drainage _ lacked in rude w of T* drainage tasted In upper iA of Phe drainage mm (max Is) Base Flow! -4.r,*e <5 acres _ sire 5-10 arras stze > 10 aces rtm-m orlalmmore vretiand — mld-sloped wetland depesslons, headwaters, bogsAacg 'round Water b=ed in lower 1jjOf the drainage located in Riddie M of Me drainage _ tocaed In upper 14 of riedr.*Me Support , 1 ab flooded or saturated flooded seasonaly or sernt-permanently permanently flooded or sa4rated, or flooded or saurated Intermittently wposed no WW-S VX" fish Populations tow flow-Mnsitive AM populatianS . _ high Aorv�9er%A" populations pints L on -Site ordownstream on -site or downstream oontlguous wt h Ste in MgMy (max 15) pemteabte strata r o s i o n / SMM wasstleft or no veg Wong _ sparse wood or veg along OHWM dense wood or veg along OHWM - OHWM wetland extends 30 - 60 m from h o r e l I n e x wetland extends < 30 m Prom � O H W M _ wetland extends > 200 m from Protection OH WM highly developed slnoreine or _ moderately developed stnorerrne or O H W M subc�t undeveloped shorerne or I•y points sub=XhMM sL m (max 9) Pater Cual ity — rapid lbw tivaugh sire _ moderate Now through sae . slow flaw through sae ]Z < 5o % veg cover _ 50.60 % cover > 50 % veg cover Improvement _ upstream in Darin horn wetland Is s 50% of basin upstream from ! > W% of basin. upstream Prom mbel aped wetland is dewyloc d wetland is developed pokxs LQ ( holds < 25 % overland runoff _ holds 2S -!;a % oveond runoff holds > 50 % overland runoff (max 12) d1A - Not Applicable, M NNo information available )ominant Vegetation- Wildlife: Wetland and Buffer Functions and Semi -quantitative Performance Assessment Natural " sixe 45 acres ow Vag structtwe Biological = serer surface water Support — one habtal W PAS POW REM PSS PFO EST low plats dversty (< 6 species) pobts Z 3 (max 36) Overall Habitat Function points 7 (max 9) Specific Habitat Functions poirn (Max 15) Cultural/ Socioeco- nomic poire 6 (MU 21) Notes: > 50 % Washre specs — iow primary productivity -- low organic aocurnu4'rtiorr. low organic export lew habitat battxes IL bullets very disturbed LSOlated iron uptand habitats n sae c s acres low habitat aversity low Sa xKoy or rekxW low krvenDI) le habitat bw amphMn habitat low fish habitat low mammal habitat low bird habitat X low educational opportunt9es low aesthetic value lacks commercial fisheries. aq*: uitum. renewable re -sources — Licks historical or archeological resources We passhe and active PdWM r opporrirntias owned not near open space r size 5 -10 acres 2 ieveF veg permanent surtsoa water two tit lirpes PAS POW PEM4�DFOEST moderate plant diversity (7-1 S spy _ 10 io 50 % invasive species .X -ate pdmwy► pmducff^rtl► moderate organic: accurWagon krnrorgaft expw Some habtat ieattmas buffs stiotly disEurt+ed pmed o emociloupiartd habbis sae 5.10 acres � rn(derM habW CRWSty „_„ moderate sarmary or r eFuge moderate invertebrate hW4at modem amptAgan habitat _ mnderare lish habitat moderate mammal habitat moderate tirtf habtat moderate educational opportunides modem /aesthetic value moderate commerciat lshedes. agr5ctftre. renewable resources historical or a Thedogipf Ste Some Passive W4 acx" recreational opportunities _ privately owned sortie pubic. size > 10 acres ram v'eg Muctu e open waWpoft through Vxrmw habtattype6 PAS POW PEM PSS PFp ETr - high plant divw* (> 15 spec>es) < 10% krvastoe species � ar9arlb aMalulation OrgmtC WWt well carrteaed 10 upland Habitats — size > 10 acres — high habits *Mcay — high sanctuaryor refuge — high invertebrate habtat high amoblan habitat — high fish habitat — high mammal habitat high MU habitat high educational oppwu*m es _ high aestheW value high oommercial ftsheties, agricutt e. renewable Msourc es knportars hiMrical or arcimbgical site many passive and acWe recreatlonat opporantses unrestricted pubic access Mcoycor><tWW to Open Space n.. Wetland and Buffer Functions and Semi -quantitative Performance Assessment !tiand # Staff Date :ationT_—RO�J' 6— ------ --- - - Criteria Function Group 1 1 pt Group 2 2 pts Group 3 3 pts Flood/ sfie < 5 acres _ size 5-10 acres -� size > 1 o acres Storm Water _ r ire or laleshore wetland — mid -sloped wetland . regions, headwatw, togs.Aafs < 10 % bMsted cover _,., 10 - 30 % forested cover _ > 30 % brested cover Control — unoarufrained outlet — semi -constrained OWet 44� c,m"berr W outlet teased in lower 113 of the drainage — bc:ated in middle In of T* drainage _ boated it upper in Otte drainage points (max 15) Base Flow/ 'round e <5 acres orla�1Ore wetland — size 5-10 acres — mid -sloped wetland size > 10 acres —Y�epression,s, headwdtem eogs,aaM Water �� K b=W it lower 1A of the drainage ,., located in middle 1A of the drainage i1 upper 1A of the drainage Support — " flooded or saturated — seasonaly or semi mrTnanerwy Maaneruty koded or sa xamd or �no flooded or salura W intermeeruy exposed I Aow-sensitive Rsh populations _ low flow-sensitive fish populations _ high now-senS" populatlons poiw�5 on --sale or downstream on -site or downstream 0Mfiguous wtEhh site in holy (max 15) pern-teabie strata ros i o n / — sparse grass+1mbs or no veg along _ sparse wood or veg along OHM � dense wood or veg along OHM OHW M wetland extends 30 - 60 m hom i h O r e I i n e wetland odends < 30 m l rom — O H W M — wetland er4ends > 200 m trom r o t e c t l o OHWM _ moderately developed shoreline or OH W M �POM/ — higftly developed stwrWo or subcalchm M undeveloped stror�rre a suticatch7wt subcat:hmem (max 9) Nater Quality rapid lbw through site — moderate now through sae T slow now Mrough s¢a Improvement < 50 % veg Dover — 50 - 80 9b Dover �/ ? 80 % veg cover — upW�eam in basin from wetland is — s 50% of basin upstream from -se > 50% of basin upstream Iran LV urdeveloped wetland Is developed pedaM is dev+ebped poitgs bolas < 25 % overland runoit — holds 25 - 50 % overland runoff holds > 50 % overland nmoff (max 12) 'A - Not Applicable, NA = No information available ominant Vegetation: Wildlife: Civl�Qfi Natural Biological Support pc9nts (max 36) Overall Habitat Functions Points .27 (max 9) Specific Habitat Functio points V (max is) Cultural/ Socioeco- nomic MM (max 21) Wetland and Buffer Functions and Semi-quan itative Performance Assessment $tto C 5 acres ag tuft low veg strumn seasoner surface water _ one habitat type /PAS POW PEiu PSS PFO EST e* bw plant diversity (< 6 species) _ > 50 % invasive species low primary productivity low organic 6=xnuiati3n b, �ha0tak boxes iters very CISWrbed Wated fmom upland habitats site < 5 arcres low habitat diversity low w4tuary or reArge low Invertebrate habitat rw amphibian nabaat bw fish habitat low mammal habitat low bird habitat low educational opportunities yr low aesthetic value Tacks Commercial fisheries, agricultum renewable resources lacks historical or mcheabgiear re5otraes ]//Pwatelyowrw acics passive and active ecreational opportunities Z not near open space Notes: OLp :QVa%STkr?� k?46�,Al r.. size 5 -10 acres 2 level veg permanent surtace water two11 PAB PSS PFO EST m nit diversity (7-15 species) 010 50 % invasive Species noderate Vknary pmdacf VkY mooeraae organic accurmdallon bw Organic export some habitat features butters sightly Qtsttxbed pMW awiecwd to upland habitats size 5-10 acres moderate habiiaidiversty modarale sanauary or refuge � nvertebrate habitat Moderatee amphibian hatAat moderate fish habitat _ moderate mammal habta< V moderate bird habitat moderaite educational opportunMes nSOdBM iassmetic YaW moderate commercial fisheries. agriculture. renewable resourM historical or archeoioglcal site some passive and active recreational oppomint ies pdva * owned, some pubic to open space size > 10 acres No vW strt"re open water pouts through sunyner >_ 3 habitat types PAB POW PBA PSS PFQ EST — ,high plant dlverSty (> 15 species) j/ < 10% inraslve species high terry pnDojW ty high organic aca>r Mon high organic art many habitat batures buffs not dsitrbed wet OonneGM to upland hebk= size > 10 acm high habitat divemty _ hQhSM=ary0rnAW high invertebrate habitat high a rnphibian habitat high fish habitat high mernntlal habitat high bkU habitat high educational opporlury ies hgn ae5d7ebC vaiMfe high commercial fsherin agricbse. renewable resources important historical or art heabgical Ste many passive and active rec earional opportunities untestiaed pubic access . dreary ownected bit open space Wetland and Buffer Functions and Semi-quarditative Performance Assessment Aland # U staff I—PM 19 3fN 666 ration 51R_ Date Criteria Function Group 1 1 pt Group 2 2 pts Group 3 3 pts Flood / size 5-10 acres size 1 a saes Storm Water rlvertrne or lalaeshore wetland yZ — mfd sloped vvetland tarested depresshxm headwa em goes MAS < 10 % Witted cover — 10 - 30 % cover > 30 % brested cover Control unoortisrai,ad outlet — semFoonsnained outlet wt+rerub Mned outlet �{ grated in tower in of the drainage _ bcaaed In middle 113 of ttte drainage b=ed In upper I of Ole drainage gor>tS (max Is) Base Flow/ — size <a acres — sae 5.10 awes size ? 10 acres Aver ine or takeshore wetland _ mkk4opod wetland depre5sfais, heady C7ogs.Aars hound Water bead In bw9r In of life drainage — bcated in middle in of the drainaga bmted in upper 1A of Me drainage Support —vnVyW eooded or saturated _ seasonally or sw*pem7anendy pennaneruty hooded orsatunzoA or tloo0od orsamxated lnteenimendy exposed pF! no tbw-sanslove AM populations — low flow -sensitive t sh populations downstream high Aow*SertWm poµ Wons orl4e ordows�uearn orrsAe or Contiguous with $Re In highly (max Is) peanteable strata r o s 1 o n / — sew or no veg akM —sparsewood or veg along OHM dense wood or veg along QHVftA h o r e l i n e OHWM — wetland adends 30 - 60 m ham _ wetland evends < 30 m bm O H W M wetland odends > 200 m 4um I r o t e c t i o n OHW M _ moderately developed shoreline or OH W M htgrdlr developed shoreline or subcat rinim _ undevebped shoreline or Points A (max 9) sui Calich tent subcalchmM 1 Nater Quality — rapid now tl=uO site moderate now MUM site slow now through site I m r o v # < so % veg Cover 50 - 80 % cover s so % veg Cover P e m e n f upstream In basin vn wetland is — S 50% of basin upstream from M% of Davit. upstream tiom undeveloped wedand is developed ' -. v013'rd IS developed Mint — holds <25 % overland ninon — Bolds 25 - 50 % overland natalll holds > 60 % overtand ninon (max 12) A = Not Applicable, N11= No information available xninant Vegetation: A t-A L-A O 5r- Wildlife: Natural Biological Support Points-1-5 (max 36) Overall Habitat Functiol�s �,ts— (rriax 9) Specific Habitat Functions pests (nm t5) Cultural/ Socioeco- nomic points 7 (max 21) Notes: Wetland and Buffer Functions and Semi -quantitative Performance Assessment sire c 5 acres 119 lan4 low veg st uch" seasonal surface water �[ one habitat type PAB POW 13134 PSS PF0 EST low plant dhrersity► (< 6 species) > 50 % invasive species iawa�an►�r low organic a==Aa>ton. >ow« Few habl at leatur es buffers very c1sturbed �aared rn0m hags size a 5 acres low habkat diversity low sanctuary or refuge & low invertebrate habitat low amphrbw habitat low fish habitaat low mammal habitat k w hind habitat low edtxadonal opportunities. low aesdwW value tacks commercial fisheries, agriarlwre, renewable iesounces lacks historical or ar*otrx" resources lacks passive and active recreational opporturibees pdvatialy owned riot near open space size 5 - to acres 2 level veg perrimm t surface +rater _ two habitat types PAS POW PIRA PSS PFO EST _ moderate piaru divensty p-its species) 10 10 5o % invas" species ate ity moderm oWft — low Mark export _ some habta features _ buffers sfigtrny diSitnrbed pwtt* corrected to upland habtars size 5-10 acres moderate habiiat dversty moderate sanctuary or rekQe nwderate invertebrate habitat rrroderata amphbian habitat moderate Ifsh habtalt moderate mammal habitat moderate bind habiiat moderate educational opportunities moderate raeslhetic value moderate cornrnencW lisherim agria,lkm reviewable resources _ historical or anavX* gical Ste some passive and active rerreatlona l opportunities _ privately owne4 some PA*. some ox0ection to open space stie > to apes � ve9 �trr�rrs 4habWtVWater M s rgough sung PAB POW P94 PSS PFO EST .ham < 10 6 invasive shigh pdrnary species)ant diversity p. is Prod high 0FW* mA* ._M&W habitat 19atures wail00rWI0CIed to uplaW habitats — Size > to acre, high habitat diversity r high sanctuaryor Muge high Invertebrate trabtait high ampibian habitat ho Fish habitat high mammal habitat _- high bird habW high educaWnai oppaLjnWS high aestheticvatue ,- high commercial Gshedes, agriculture. renewable resources important historical or archeological site many passive and active recreational opportunWs unrestricted public aoaass Meaty connected to open space Wetland and Buffer Functions and Semi-quari itatire Performance Assessment etland Staff 5PM Date 9 -cation S 3' R Criteria Function Group 1 1 pt Croup 2 2 pts Group 3 3 pts Flood / Stie < 5 acres riv erine ortaleshore wetland _ stze 5-10 acres — mid-sloWwettand — size > 10 acres — depressions, headuratecs, bDV Vats Storm Water < 10 96 bresced cover — 14 - 30 % Oorested covet > 30 % brested cover Control unoxvwariedoutlet — senU<*nstrainea ormet a,lverUberrned outlet located 0 lower U3 of the drainage located in nicale In of lane a ainage _ bcZed in upper I Z of the drainage age (Max 15) Base Flow/ size 5 etas — size 5-10 acres stze > 10 acres =round Water dye" orlaiaeshorewetland _ mid-siopedwedwd — depress hoad �� _ band In lower U3 of the drainage _ _ bcated in middle 1A of the drainage located h upper to of the drakkW Support — wffpxaN sooded or saurated — seasonally or semilpermanerW permanently flooded or sal xwea or hoodedorsau rmed intermitter*emosed 7 -X no flaw-5er%lve IM pop0mions — low fiovwSensttltire RM populations. _ high &yw- 8rtsl " pop g=M poinlS on -sate ardownstream on -site or downstream contiguous with site In highly (max 15) permeabie strata : r o s i o n / ,..sparse Wasstwrbs or no %eg along _ _ spore wood or veg along OHwM _ dense wood or veg WON Olim OHW M wetland Wends 30 - 60 m from Shoreline _ weLW extends < 30 m from O H W M _ wetland extends > 200 m Wom Protection OH WM — moderately developed St7mkm or OH W M hW* developed avrefine or subcatrct-went — undeveloped shon*)e or ; Points ant subcatdlxnerm (max 9) Water O u a I I ty — raPld low thin site moderate low through site 2K slow lbw through $ite <5o % V" cover 50 - 80 %cover > 80 % veg cover Improvement _ upm9V in baste from wetland is — s 50% of basin up s rearn lawn > 50% of basin upstream from P*Z undeveloped holds < 25 % wetland MMOt wedand Is developed `: — holds 25 - 50 % overland runoff wedand is developed holds > 50 % overland runoff (max 12) /A - Not Applicable, W1= No iElformation available vminant Vegetation: �Fy LA CO ST RV Df- A L- RU Wildlife: Wetland and Buffer Functions and Semi -quantitative Performance Assessment Natural Biological Support stets (Max M Overall Habitat Functions P� (fT=9) d- size c 5 apes ag W. law veg stniatrre seasonal utace v+rater one habtat type PAB POW PEN! PSS PFO ESr low plant dversity (r 5 spades) a 50 % hvasive species low primary productk* tow organic acartwlation, lawn organic low habitat batures bufiersverydsturbed }� Isof Md tram trptand habitats y� size < 5 apes low habitat dversity low sanr My or rekrge stye 5 -10 apes 2 WM veg permanent surface water — two ha�biat types PAB POW PEM PSS PFO EST r moderaw plant dversd (7-15 species) 10 to 5o % invasive spades ' modem organic a=wxrhallan some babitat features biffem slightly disturbed patfdaey Connected to upland hams stze 5-10 acres moderate habitat dnrersky moderate sanx;tuary or refuge size > 10 acres en p°°is`'"acer ,'ftmw PASF@�FO EST high < 10% ktkart sag ? Ay high ocgautic no Pknw R acmXnftjon — high organic expOr nimW haft baftres buffers not dmxWd vM1 catneaed b upland habtats — sire 310 acres — high habitat amrsity — highsWaua(yorM*M specific low bmwbrate habitat moderate invertebrate habltat — high invertebrate ha U low a�� habitat moderate aniphWn habtat — high amphlbian habitat Habitat low fLSh habitat — rttoderata fFsh habitat _ high fESft habRaa Function � burr mammal habitat — moderate mammal habitat — high mammal habitat points T low bird habtat moderate gird habitat — high bird habitat (max Is) Cultural/ Socioeco- nomic po:nts7 (Max 21) Notes: lour educaWnal opportunities low aestiremic value tacks commercial fisheries. agriculture, renewable resources x — lacks historical or archeological 2C resources lacks passive and atcum reaeaUnnal opportunities privately owned — )L not near open space moderate educational opportunges rnlpdB m Ae5time0c value moderate commercial Ashenes. agrt uftw. renewable resources historical or arCheological sae some o&v; m and active privately awned, some pubic a0Qe3s some catnoc k n to Open space high educabonai oppo =6% high aesthetic value high commercial fisheries, agriculture. renewable resources important histaftal or ardteologW site many passm and active recreational opportunities urm3sMc ed pubic aooess _ drectlyca+neded to open space Wetland and Buffer Functions and Semi -quantitative Performance Assessment etlanl jl� r Staff TpAI Date - -3 ' -3 T - -;Z-9 14111 0-4 ,,cation S T R Function Flood/ Storm Water Control points 11 (max 15) Base Flow/ Round Water l Support ! poira , (max 15) rosionl Shoreline Protection pokns N/A (Max 9) r Water Quality Improvement poinitsz (max 12) A Group 1 1 pt I Group 2 stze < s acres dvwk* or lalceshore wetland _ t 10 % brested Cover _ unoatsaaiied outlet located in lower 1 r3 of Vv drainage X size = 5 acres riverine or Mdlteshore wetland TC-10cated In ewer 14 ct the drainage IV- mmporaly flooded or safiurated no flow sensitive 10 populations on -site or dowr%Zeam sparse grasst rbs or no veg along OHWM wredand moends < 30 m from OHWM highly developed shoreline or rapid tow through site < 50 % veg Cover _ upstream In basin tram wetland is tndl"eloped holds < 25 % overand runoff NIA — Not Applicable, N/1= No information available uominant Vegetation: Po l A Rv �p 6-V RV oL Criteria 2 pts I Group 3 size 5-10 acres mid -sloped wedand _ - 10 - 30 % brealed cover sen*cormalned outlet bcated in middle 14 of Me drainage size 5-10 awes mid -sloped wetland located in middle 1/3 of ffle drainage seasonally or seml-permanently flooded or sadxatea - low flow, -sensitive M populations - on-,Ae or downstream sparse wood or veg Clang OHWM vmtland extends 30 - 60 m from OHWM moderal* developed shoreline or subcatdvneru moderate flow it ough 540 50 - 80 % eater s 50% of basin upstream from wetland is developed holds 25 - 50 % overland runoff Wildlife: 3 pts — size > 10 acmes -( depressions, headwaters, bogs Rats .`( > 30 % Ibrested Dover ?� Culvertlbermed oWet located In upper 193 of the drainage ,size 10 acres hOadwMeM bogs W located in upper 1A of the d-aWge Permanently 1100d0d or smxaU4 or intermittent oVosed high flow-sensuve populations comfiguous with site in hlghfy permeable strata dense wood or veg WongOHWM - wetland edends > 200 m kom OHWM undeveloped shorefine or sum f , slow now dxough s4e > 60 % veg cover > W% of basin upstream from wedand is developed k holds > 50 % overland runoff El Natural Biological Support points —L5 (man 36) Overall Habitat Functions points .l (man 9) Specific Habitat Functions points-6 (max 15) Cultural/ Socloeco- nomic points Z (max 21) Notes: k�r- f: Wetland and Buffer Functions and Semi -quantitative Performance Assessmeru 5fte < 5 acres aq land, low veg svucnma �[ seasalal aw ace water one habitat type PAS POW PGA PS9(�q EST low punt dversky (< 0 species) _ > 50 % irvaslve species low primary productivity low organic a0axa radon low organic export low habitat balm buffiers very disturbed Isolated ram uparrd habitats e< 5 crones ,00WW t dver5ky bw sanctuaryor refuw X_ low Invertebrate habitat low amphibian hab[at low fish habitat tow mammal habitat .� low bird habitat ^ low educational oppommities _ low aeWmW vakm tacks commercial risheries. agku ltuM renewable resources lads NMNkN i or arctw*0cal resources We passive and active recreaticnai opportunities low rtct near open sl7ace sees -loam 2 level veg pertnarlent Wrtaoa water two habitat types PA13 POW PEM PSS PFO EST moderate pant aversity k7.15 spedso } 10 10 60 % invasive species moderate primary produC" moderate organic aoarr lotion loworganio export sarre habitat features buffers "aly cf5tt abed parmy oortnecl ed to upland stze 5-10 acres moderate habitat dversety — rrloderate sarrarrary a reAuge moderate lrtvertebrW habitat moderate ampMban hab[at rrKXXfat9 AM habitat moderate mammal habitat moderate bird habitat _ moderate educational opponurvdas rnlode M taesthetic value moderate commercial fisheries. agria M". renewable Mources hl5loricaf or archeological site some passive and active recreadmaf oppo[QYlws privately owned, some public some connection to open space — s€ze > 10 acres high veg strucil" stmnmer PAS POW PEM PSS PFO EST � 0%krwd ' 15�ec�a5) cies high primary prodtitgvty high agaft aOMXMAaOM high *vM* export many habitat ie buffers not *Mxt)ed wel connected to up[arrd habitats — size > 10 acres — hfghhakbitatdiversityr — high sanmaryormeXje high iwenebrdte habitat high amphWn habitat — high fish habitat — high mammal habitat high bird habitat high educabonal opportunities high aesthetic value high commercial fisheries, agria,lture, renewable resources Important historical or archeological site many passive and active recreational oppoMmIties unrestricted public access directly connected to open space Wetland and Buffer Functions and Semi -quantitative Performance Assessment ttland #_ — _ - . - Staff -E t7M Date -2i 3 ZQ 2,fy OS cation S T R_ Criteria Function Group 1 I pt Gxvup 2 2 pts Group 3 3 lts Flood/ -- sire < 5 acres = size 6-10 acres size > 10 awes Storm Water dvedne or fat -shore wetland _ m id -sloped wetland 1( depr ors, he� bogs,&= < 10 % brewed cow _ 10 - 30 % forested cover > 30 % Iorested cover Contra] unconstrained o let _ semfconsvained outlet aAet warw outlet based In iower 1 fd of Jv drainage _ located In middle 1 r3 of the drainage located in upper iA of O dralnVe Minis _qs. (max Is) Base Flow/ size <5 awes taloashore wetland _ stze 5-10 acres mld-sloped wetland size > 10 acres depressions, :round Water _ rtverirte or _ NM1wMeM �� boated lo lower 14 of the drainage boated in middle tr3 of Me ftinage _ located in upper 1A of the dr*UW Support al y saoded or satur' _ seam �y � rrnarternty permanently flooded or sat XWft or flooded ir>termimeraly exposed no Sow -sensitive fish populaton5 — low llow-sensl" fish populations downstream — high flow -senses populations pokm -Z on -site ordownsirearn otNs4e or caniguous with site In hig* (max 16) pem'teabie strata r o s i o n/ —sMw grassd"rbsor no veg — sparSe wood or veg along OHWM _ dense wood orveg along aJ h o r e i i n e OHWM — KeUand extends 30 - 60 m item iS _ wetland extends < 30 m torn O Hw M _ wetland eidends > 200 m tarn Protection OHWM mod&Wetydevelopedshoreline or OHWM — highlydevebped shoreline or sutx�trrterrt undeaebped shoreline or s�udment subcal;hment �� (max 9) Water Ou al i ty — r;ipid lt]w ttMOugh site moderate now through site slow lbw trough Ste <50 % veg cover _ 50 - 80 % oover �' > 60 % mg oover Improvement _ in basin ham wetland is S 50% of basin upstream frnni > 5046 of basin upstream tram unduyelotw wetland is developed `;. ,wwettand is developed poi n iz— adds < 25 %ovedand rtmofi — holds 25 - 50 % overland r mil holds > 50 % overland smolt (max 12) vtA - Not Applicable, N/I = No information available Dominant Vegetation: �U p� Wildlife: Wetland and Buffer Functions and Semi -quantitative Performance Assessment - Natural Biological Support pointsr 3 (Max 36) +� size s 5 acres ag lard. low vag strum" Yseasonal surAM crater onehabtat PAS POW MPSS PFQ EST low plant Oversity (�K 6 SPecles) > SO % Inva.5lve Spades bw pdm aryprodurlvity loworyanic accumulation low organic export lewhablat laatums buffers very disturbed isolated Aom upland habitats site 5.10 acres 2 lard veg permanent surface water two habitat types PAS POW PSA PSS PFO EST moderate plant day (7.15 spedwo 10 a sim 50 % InvaWecies 2 anoderaoe prImW pvduetivty — moderate organic accunauladon loworganla export ,r some habitat leatrues buffers 59g * disturbed bard* aarrneCW to upland habitats — size > 10 acres l" — high veg structure — open water ftugh ._ . habitat types srnrxnet PAO POW PEM PSS PFO SST high plant aver* P. i5 species) 10%invasive high orgartft: many habitat features bJ*rg not drsxbed wall connected to upland hates Overall size 15 acres size 5-10 acres _ size > 10 awes low habitat drvers4y i moderate habitat diversity _ high habitat dimsity Habitat T low sancluary or relate _ moderate sanctuary or nAVe „_ high sanctuary orr Functio�y5 tit (Max 9) Specific Habitat Functlo s fits (Max 15) Cultural/ Socioeco- nomic polnt7 (Max 21) e low krMM brats habitat low arrtphrbian habitat low tish habitat low mammal habitat low bird habtat low e*=tlonalopportuntti s low aesrtr W value lacks Commercial fisheries, agriaft". renewable resources lacy historical or arc heoiogical resourm X ta,ckS passive and;aaj,,* recreational oppomt nil*s pd+AYowied not near open space` Notes: � �� F/C t moderate invertebrate habitat moderate arrrphbtan hatrtat moderate AM habtat moderdte marraW habitat rtroderate bird habitat moderate educational oppomnnities moderate faesrhetic value — moderate commercial Ishertes. agrcuMme. renewable resources hisloiiGa[ or archeological sate some passive and active recreational opportunities privately owned, some pubk same cortnectlon to open sparse — high Invertebrate habitat high amphibian habtat — high rrsh habitat — high mammal habitat _, high bird habitat — Migh educational opportunOes — high aesthetic value — high commercial fist*des, ag Culture, fen&ffable resources important historical or arCtreobglcW Ste many jx s and adive recreational oppommoks unrestricted pubic access dinecity connected to open space Wetland and Buffer Functions and Semi -quantitative Performance Assessment retland # Zi Pwas e ocation S T R Staff �Eo Y" Date 3 ; f 7 Criteria Function Getup 1 1 pt Group 2 2 pts Gmup 3 3 pty Flood / J sire < 5 acres size 5-10 aces _ size > 10 acres Storm Water dver#ne orlakaOore wetland mid -sloped wetland _ depressto m headwaters, bogs.itats < 10 % formed cover _ 10 - 30 % lorested cover _ > 30 % forested cover Control unoatstraine4 outlet semiconsltra W oudec culverVbemed oudM located it lower 1 f3 of the drainage located in middle i M of the drainage — located in upper In of the drainage points (Max 15) Base Flow/ size <5 acres _ size 5-10 acres — size > 10 acres riverim or Wtesttore wetland Y mid sloped wetland — depressions, headrirad M bogs,ilats Ground Water bcmW in lows[ y{3 of the drainage _ located In middle 13 of the drainage _ located In upper I of the drAlags Support iC temper* flooded or saturated -_ seasonally or semi -permanently permanently noodled or sanmaoed, or flow fish hooded or saturated tow lbw-sensidve rash intermittent y exposed high lbw-sanWM �} no -sensitive populations _ poputations populations ort-site or downstream on -Site or downstream contiguous with Site in highly (max 1s) pemseable strata Erosion/ sparse grassilwts or no veg along _- - sparse wood or veg along OHWM _ dense wood or veg along OHWM OHWM wetland extends 30 - 60 m kom Shoreline _ _ w edw4 extends < 30 m from O H W M _ wetland extends > 200 m trom Protection OHWM _ moderately developed shoreline or OHWM _ highly developed dxx ekw or subcatdhment undeveloped shoreline or , po� submthment Sut calChment y (max 9) Water Quality — rapid ADW trough Ste moderate flow through site scow now through site < 50 % VW cover _ 50 - 80 % cover > 80 % veg cover Improvement uMeam in basin trwn wetland is _ s 50% of basin upstream from > saw of basin upstream from Undeveloped wetland is developed wetland is developed pokZ LO holds < 25 % overland runoff hobs 25 - 50 % overland runoff _ holds > 50 % overland runoff (max 12) !!A = Not Applicable, Nil = No information available )ominant Vegetation: p14 Rv r� io:— -41- Wildlife: Wetland and Buffer Functions and Semi -quantitative Performance Assessment Natural Biological Support points A (Max 36) Overall Habitat Functions point s -I (max 9) Specific Habitat Functions points -i (Max 15) Cultural/ Socioeco. nonlic points 2 (Max 21) Motes: &,ARBEr stze < 5 acres ag land. low veg slructure seasonal surface water — one hatliat PAO POW PSS PPO EST low plant versity (< 6 species) > 5o % irrasive species low primary productivity Iow organic a�rrrnetatlon �[ low organic export lew habitat features NAM very drshrrbed isolated from upland habitats size < 5 acres low habitat diversity low sanctuary or rehuge low invertebrate habitat low arnphrbtan habitat low lash habitat [ low mammal habitat low turd habitat e\_ low educational opportuniues low aesthetic value lacks commercial fisheries, agricudure, renewrable resources lacks historical or archeological resources We passive and active mmatbnal opportunities ply owned not near open space PIUQ C cL C DnIMZ TO 7-0 MAX C 04r W—A I stye 5 - to acres 2 level veg peMM*M surface water �.. two habtat types PAS POW PEN PSS PFO EST _ moderate Plant diversity (7-15 spesles) 10 to 50 % invasive species moderate pdmarY productivity moderate organic a0awAittlon low organic effort some hatAx leans butlers slightly disturbed �. pXd* =W*C ed to upland habtats st=e 5-10 acres moderate habitat diversity moderate sanctuary or AAM moderate lrwenabrats habitat moderate amph0w habtat moderate rash habitat — moderate mammal habitat — modem bird habitat Y moderate educational opportunities moderate laesrnetic value — moderate commercial tishenes. agriculture. renewable resources historical or audteoWgical site — some passive and active recreatlo oopportwOes privately owned, Some pubic — size ? 10 acres ~~ — high veg sdeteltre — open ha�ttyM ' bough surnrner PAB POW PEM PSS PFO M <high plant 10ske cr5�y► 15 Species)— igh primary — hhlgh Organic omamA io — high knit: export mi leaDires — buUM not dis rbed — wel connected to upland habkats . q _ . size > 1 o acmes high habitat diversity — high sanctuaryorreluga ' — high hveMbrate habitat — high amphMn habi ai — high fish haNat — high mammal habitat high bad habitat high educational opporpmities high aesaxfic value — high commercial fiShertes, agriculture. Mrmyable resources — important historical or arctwiogical s+te — many passhm and 8giv9 remationai opporernitles — unrestricted PLM aa= direWy cmneaed to open space