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HomeMy WebLinkAboutMisc'A0A Altmann QAve 1-kss c�icttcl_SA , ITC ento Divisio t July 6, 2010 AOA -3941 Jack Zhengin: West West Pacific Development 4957 Lakemont Blvd SE, C4-323 Bellevue, WA 98006 SUBJECT: Critical Areas Study for West Pacific Short Plat 16466 109th Ave. SE, Renton, WA (Parcel 008800-0495) Dear Jack: On May 26, 2010 1 conducted a wetland reconnaissance on the subject property utilizing the methodology outlined in the 1997 Washington State Wetlands Identification and Delineation Manual. The western portion of the property is currently developed with a single-family residence and associated yard. The central and eastern portions of the site are primarily forested and slope gently to moderately down from west to east. One Wetland (Wetland A) was identified and delineated in the eastern portion of the property (Figure 1). The on-site portion of the wetland is part of a larger wetland that extends off-site to the north and south. Vegetation within the on-site portion of the wetland at the time of the site visit consisted of a palustrine forested plant community that included red alder (Alnus rubra), willow (Salix sp.), Oregon ash (Fraxinus latifolia), red -osier dogwood (Cornus sericea), salmonberry (Rubes spectabilis), black twinberry (Lonicera involucrata), spirea (Spiraea douglasil), slough sedge (Carex obnupta), and mannagrass (Glyceria sp.). At the time of the field investigation, most of the on-site wetland contained several inches of ponded water. Soils throughout the non-ponded portions of the wetland were generally saturated to the surface. In addition, some sheet flow within the southeast portion of the wetland was observed draining south. Attachment A contains data sheets prepared for a representative location in both the wetland and upland. These data sheets document the vegetation, soils, and hydrology information that aided in the wetland boundary determination. -WO Jack Zheng July 6, 2010 Page 2 Wetland A appears to meet the criteria for a Category 2 wetland per RMC 4-3- 050M.1.a.ii.d and would require a standard 50 -foot buffer per RMC 4-3-050M.6.c. Proposed Buffer Averaging The project proposes to utilize wetland buffer averaging. Wetland buffer averaging may be allowed by the City of Renton if all of the following provisions of RMC 4-3- 050M.6.f are met: That the wetland contains variations in ecological sensitivity or there are existing physical improvements in or near the wetland and buffer; and The area in the vicinity of the proposed buffer reduction currently consists primarily of Himalayan blackberry (Rebus discolor), trash, and yard debris and does not provide any significant habitat value to the wetland. The area in the vicinity of the proposed buffer replacement is generally forested with a native plant community of red alder, big -leaf maple (Acer macrophyllum), hazelnut (Corylus cornuta), thimbleberry (Rubes parviflorus), sword fern (Polystichum munitum), and fringecup (Tellima grandiflora) . ii. That width averaging will not adversely impact the wetland function and values; and Since the proposed buffer reduction area is dominated by Himalayan blackberry, a non-native invasive species, and is not currently providing a significant habitat or water quality function, there should not be an adverse impact to any wetland functions. Furthermore, since the proposed buffer replacement area consists of a more diverse native plant community, there should be an overall increase in the habitat value of the buffer following averaging. iii. That the total area contained within the wetland buffer after averaging is no less than that contained within the required standard buffer prior to averaging, and Under the proposed buffer averaging plan, 428 s.f. of buffer area would be reduced and replaced with 467 s.f. of additional buffer area for a total buffer increase of 39 s.f.. iv. A site specific evaluation and documentation of buffer adequacy based upon The Science of Wetland Buffers and Its Implications for the Management of Wetlands, McMillan 2000, or similar approaches have been conducted. The proposed buffer standard is based on consideration of the best available science as described in WAC 365-195-905; or where there is an absence of valid scientific information, the steps in RMC 4-9-25OF are followed. Jack Zheng July 6, 2010 Page 3 The proposed buffer averaging plan would increase both the overall size and habitat value of the buffer over current conditions and is consistent with best available science. v. In no instance shall the buffer width be reduced by more than fifty percent (50%) of the standard buffer or be less than twenty five feet (25) wide. Greater buffer width reductions require review as a variance per subsection N3 of this Section and RMC 4-9-250B; and Under the proposed buffer averaging plan, the minimum buffer width would be 29 feet and would not be reduced by more than 50% of the standard buffer. vi. Buffer enhancement in the areas where the buffer is reduced shall be required on a case-by-case basis where appropriate to site conditions, wetland sensitivity, and proposed land development characteristics. Since the remaining buffer in the vicinity of the proposed buffer reduction consists of a native forest there should be no need for additional plantings. vii. Notification may be required pursuant to subsection F8 of this Section. Provision noted. If you have any questions regarding the wetland delineation or proposed buffer averaging plan, please give me a call. Sincerely, ALTMANN OLIVER ASSOCIATES, LLC John Altmann Ecologist Attachments 8mp U l -90-LO-1 IYV- I b5 E aas�nax If O -l- NOlJNVHGIVIII',L.�, 'NOI�Nyy1y�..,�i �dc�sP'-j alva �� IAV r 11. V O l 1 V 9� Au�wvid �VLq�uiuOn��V..]j {,r�S4LlE ISib!xri SLiFtfL SiLt�"11Cf Y�OBt, t'm'��K�:1 x�S xDSL{IJ 4 ON SV lV-1d -L?�OPG �I�I�'dc _LSM �O Y D1`I `SojPjo0SSV IPAIJO UUI?W�JV NV -],::4 GNie)lv��nI ����na ��n� I X EJos i��roxa xmvxa , Lr) o 1 I o It I I a u7 co O O m O co a 00 au{„zw d i o o�on o I ' . 00 "5z J \ i ! Z� I a IF �OFb_ I � ! a �~~els (Za ¢ 2 if m �Cr- LL.I f tr Q Z 0- O o u7 O I o cc 0 cc 0 Q � O L nw LD of �Ya m 1 I Q CJ a O ! oN z o w } a2a � � _ acr• �L 5 n Ld a a N >xCD / J � 9F, t'D l U f/ O f L o D I = O o uLni � I ` f= it � � u �"'r• c �¢� 3 arc: c; SL n ,i 10 i I 7S 3n AV H160T I d U l+ cn m / N0 • • =O� O C' L x°r7°uv; w�zc U � V � i m N n ,p � n n � • I y� Z z 0 LU U I d LS) Q 0.E: O Z LU pD T` ?� °LLJ o < S(j QE Q n oLL � z�� Wiz\ CL 0 z 0 LU U I L T` z W W W Zo ❑ W W Q LL LL IL LL ❑ z > CL a_ W 13) LLIk "'i I LLI OL z 0 LU U I Encompass ENGINEERING SURVEYINU TECHNICAL INFORMATION REPORT for West Pacific Short Plat August 13, 2010 ;0 N ONAL t 1A Encompass Engineering Job No. 10552 Prepared For Jack Zheng 4957 Lakemont Blvd SE, C4-323 Bellevue, WA 98006 Western Washington Division Eastern Washington Division 165 NE Juniper St., Ste 201, Issaquah, WA 98027 108 Last 2"d Street, Cle Elurn, WA 98922 Phone: (425) 392-0250 Fax: (425) 391-3055 Phone: (509) 674-7433 Fax: (509) 674-7419 www.EncompassES.net TABLE OF CONTENTS SECTION TITLE 1 PROJECT OVERVIEW 2 CONDITIONS AND REQUIREMENTS SUMMARY 3 OFFSITE ANALYSIS 4 FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN 5 CONVEYANCE SYSTEM ANALYSIS AND DESIGN 6 SPECIAL REPORTS AND STUDIES 7 OTHER PERMITS S ESC ANALYSIS AND DESIGN 9 BOND QUANTITIES, FACILITY SUMMARIES, AND DECLARATION OF COVENANT 10 OPERATIONS AND MAINTENANCE MANUAL, SECTION I PROJECT OVERVIEW King County Tax Parcel No. Street Address Project Overview 008800-0495 16466 109th Avenue SE This project involves the development of a 0.52 -acre parcel into two single-family lots. The site presently is occupied by a single residence that will remain—the majority of the remainder of the site is wooded. The east portion of the site is low, with wetlands. Per the SCS soils map, the site is underlain with Alderwood series soil, sandy loam over glacial till. Proposed Drainage Control Because this project involves little additional impervious surface construction, formal flow control is not being proposed. Because less than 2000 sq -ft of new driving surface will be constructed with the frontage improvements and joint driveway construction, runoff from these surfaces will be collected and piped directly into the existing public, 12" storm conveyance system along the west side of 109th Avenue SE—this storm system drains into the downstream system described above. Runoff from a new residence to be constructed on the new lot will provide dispersion BMP's to discharge to the onsite wetland. King County Department of Development and. Environmental Services TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 1 PROJECT OWNER AND PROJECT ENGINEER Project Owner & � Address _qq� LA L9M&0.7-,FL-W 07 Phone I-5C-LL-VL/&Cr= ct 9!;-6V45 Project Engineer Company St -CO SS C -A -Cr Address/PhonedL — 4� — Part 311i, --TYPE PERMIT, I;AP -L-ic ATION.r4--", 7 Subdivison - t,`6hort Subdivision Grading Commercial Other Part PROJECT LOCATION AND. DESCRIPTION Project Name M!; l iq Location Township 4 - Range S ... Nf-Section '- Part 4".'�OTH ER TIEV EVVS AND PERMITS; D FVV HPA Shoreline Management CO! 404 Rockery DOE Dam Safety Structural Vaults FEMA Floodplain Other GOEWetlands Q1 Z Part 5,, SITE 60MM-ONi-r.YrAND-'DFIAIf&dE"BASIN .-'..,-. Community Drainage Basin Part 6 -;'S ITE:,C-, HARACTE R I STI CS River Floodplain 111vetlands ---- Stream /seeps/S p rings Critical Stream Reach High Groundwater Table Depressions/Swales Groundwater Recharge Lake Other Steep Slopes Part 7 :SOILS Soil Type Slopes Additional Sheets Attached Erosion Potential Erosive Velcoties Part B:: DEVELOPMENTLIMITATIONS REFERENCE LIMITATIONISITE CONSTRAINT Ch. 4 — Downstream Anal sis� '� IAB CDPS Additional Sheets Attached Part 9 ,.ESC REQlJ1REMENTS.,.., y MINIMUM ESC REQUIREMENTS MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION AFTER CONSTRUCTION Sedimentation Facilities 4,.Stabilize Exposed Surface . V:Stabilized Construction Entrance move and Restore Temporary ESC Facilities VPerimeter Runoff Control Clean and Remove All Silt and Debris Clearing and Graing Restrictions Ensure Operation of Permanent Facilities Cover Practices Flag Limits of SAO and open space Construction Sequence preservation areas Other Other 'Part 10 SURFACE WATER SYSTEM . Brief Description of System Operation _ C. 6LIACT N %LUNG Facility Related Site Limitations y v t S f lEets e pow L Q r Reference Facility Limitation ;Part X 11 ', .STRUCTURAL ANALYSIS Cast in Place Vault Retaining Wall Rockery> 4' High Structural on Steep Slope Other Tract Other Part 13 . SIGNATURE OF.:PROFESSIONAL ENGI[VEER I or a civil engineer under my supervision my supervision have visited the site. Actual site conditions as observed were incorporated into this worksheet and the attachments, To the best of my knowledge the information provided here is accurate. 4._. - Si rted/Date _. Method of Analysis Grass Lined Tank Infiltration Channel Vault Depression Pipe System Cor�pens atianlMitigati Energy Dissapator Flow Dispersal on of Eliminated Site Open Channel Wetland Waiver Storage Dry Pond Stream Regional Wet Pond Detention Brief Description of System Operation _ C. 6LIACT N %LUNG Facility Related Site Limitations y v t S f lEets e pow L Q r Reference Facility Limitation ;Part X 11 ', .STRUCTURAL ANALYSIS Cast in Place Vault Retaining Wall Rockery> 4' High Structural on Steep Slope Other Tract Other Part 13 . SIGNATURE OF.:PROFESSIONAL ENGI[VEER I or a civil engineer under my supervision my supervision have visited the site. Actual site conditions as observed were incorporated into this worksheet and the attachments, To the best of my knowledge the information provided here is accurate. 4._. - Si rted/Date _. Address 16466 109th Ave BE Renton, WA 98055 Vicinity Map 1 � m r ' SE:szrSt SE 162nd St BE 182r4 v: -Ak Fred Np�lt�q CO jj wRit$a P. School F�:,i F`reshyYpris�n % I CiT7UYC�r T1s"-tfi!'M? � BE 184tb $.z i SE 464th St S !Px i 52MSt 3; { Q Sa 4€t!16 St > m p -per.'_ � 4•FCi iF �<f�LF� ' 1 sE 1aem4'' �tb�th�S3 SE 29th St r�-�.. � a: 5 SE iEclh PI cs K, r Fn m m r{p tpf RH�Irf;:A�ri's 5E 16th sl SE 1511th St SE 1fiBth 89 ro va SE 169th PI SE 160 E _ r 'r. -S ` .Fz^• 17Y#&' 'Rt ............... . ......... ... ... ., ..,..,... 02010 Google Sap data (D20 Google - Vicinity Map w — EAP 109TH AVENUF S.E. Fxry�o.aa' IT K 9z m�min �ti _r � ovv {p w µ J V10. i n u onm m L O 0 J p O m� w� �otiq G1 2 nim 17 DOrI� z � o - NCIR`ITi F4 $a pz�-f Site Plan 75.00' �9 7 1 = 40 IL IyEh7!!� r Park in3?1. ran A,i I> I� I� 13 P. " ,;r,lf l�o.�'se � I yy � ^- �� __�,�sta r.�) - • a �t 1 h �s�:� F �* � i a J j •� 5 �-, ��� � ' =_ --rte�(' �.• - ;t. •\ � f � - n .,. � ->>-`" •'�•'-; i� � =".- � I .ate, :121;459 �1�', !/./�` ��L•" i4 - -- - �i __ IIS � II_ — J�� � .1' �`�d � ., I } � %/ M „�i:i �r"HM, �� �� -r`� I I � IL A j N' ��! P �I iT 1 , t Ill i <r £, I. I , i! ,li '1 -- i �I �� •� � I II� , i°- ! I L ;, i. SCS Still Ma SECTION 2 CONDITIONS AND REQUIRMENTS SUMMARY SECTION 3 OFFSITE ANALYSIS a Encompass ENGINEERING & SURVEYING l DOWNSTREAM DRAINAGE REPORT fo r West Pacific Short Plat August 11, 2010. �- Encompass Engineering Job No. 10552 Prepared For .lack Zheng 4957 Lakemont Blvd SE, C4-323 Bellevue, WA 98006 Western Washington Division 165 NE Juniper St., Ste 201, Issaquah, WA 98027 Phone: (425) 392-0250 Fax: (425) 391-3055 www.F,ncompassES.net Eastern Washington Division 108 East 2"4 Street, Cle Elum, WA 98922 Phone: (509) 674-7433 Fax: (509) 674-7419 King CountyTax Parcel No Street Address Project Overview 008800-0495 16466 109th Avenue SE This project involves the development of a 0.52 -acre parcel into two single-family lots. The site presently is occupied by a single residence that will remain—the majority of the remainder of the site is wooded. The east portion of the site is low, with wetlands. Per the SCS soils map, the site is underlain with Alderwood series soil, sandy loam over glacial till. Upstream Drainage Little if any runoff flows onto the site from upstream properties. Downstream Drainage Runoff from the site sheet flows west to the onsite wetland. This wetland drains south (A), then east through a 2' deep, flat channel (B) about 150' east of the southeast corner of the site where the flows enter into a 12" pipe (C). Flows continue east through the 12" pipe another 150' to the roadside ditch along the west side of 110th Avenue SE. Flows head south through said ditch (D), through a couple of 12" driveway culverts, cross 110th though another culvert (E), then into an 18" pipe flowing south (F). This 18" pipe discharges into a wooded ravine about 400' downstream from the site (G). The flows in the ravine channel continue to drain south, crossing under SE 168th Street (H), about 750' downstream from the site. South of 1681h, the channel is about 4' wide, shallow, then the ravine fans out (I), becoming a wetland. At a little past i/4 mile downstream from the site, the (lows drain into a large wetland lake (J). There were no obvious drainage problems in the downstream drainageway. Proposed Drainage Control Because this project involves little additional impervious surface construction, formal flow control is not being proposed. Because less than 2000 sq -fl of new driving surface will be constructed with the frontage improvements and joint driveway construction, runoff from these surfaces will be collected and piped directly into the existing public, 12" storm conveyance system along the west side of 109th Avenue SE—this storm system drains into the downstream system described above. Runoff from a new residence to be constructed on the new lot will provide dispersion BMP's to discharge to the onsite wetland. b m to Fi'ffiia C qr l ti — — — — — N07'43'74 E 109TH AVENUE S.F., yo azo 'S X. EOP 'Fx. aa�Nc W o m { 75. �'• TNP aaoayw,go �wWN m� mwm T� m N9O ,gy�o Ali W M ,, ❑ - , Ra 1 - .. i 4374 E- 75.00 '. Yo d A g � w m g..��mti' ' W CCo� Jtf Q V= ymlbilm Dp � � W O �T 1 2 �M mtrm N mN � �p - fft - O za Ory U r v o p mZ > m`� �mA� 0 z -a c� vm� �3 c Y�: ;'I NORTH ot�J Site Plan 75.00' 40' Sat ^a3'r4 "w 1 —I� ,� 4V'��` • � i .I��. .. 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Lq OCIL x X L —V X 9 X '1Z VIL L 4 o'lz X.4 'A L1'6zL 0 7x X V;'O�L x x 9C'9e.Lx XL 3l,6z[ � \z"� OtTcl, xy x q i 6L'OZ L SECTION 4 FLOW CONTROL AND NATER QUALITY FACILITY :►: _ 11.11 r ��liT� SECTION 5 CONVEYANCE SYSTEM ANALYSIS AND DESIGN SECTION 6 SPECIAL REPORTS AND STUDIES Altmann Oliver Associates, LLC AOA I'0 Box ")-8 CjIim 11. 11',A wmi i I [1llifx^ ( 12,) d;,;.11„V, kr ( 12')j )[K; j+,I1VIT-ol11)It: IItai �l:llllklll & July 6, 2010 AOA -3941 Jack Zheng West Pacific Development 4957 Lakemont Blvd SE, C4-323 Bellevue, WA 98006 SUBJECT: Critical Areas Study for West Pacific Short Plat 16466 109th Ave. SE, Renton, WA (Parcel 008800-0495) Dear Jack: On May 26, 2010 1 conducted a wetland reconnaissance on the subject property utilizing the methodology outlined in the 1997 Washington State Wetlands Identification and Delineation Manual. The western portion of the property is currently developed with a single-family residence and associated yard. The central and eastern portions of the site are primarily forested and slope gently to moderately down from west to east. One Wetland (Wetland A) was identified and delineated in the eastern portion of the property (Figure 1)_ The on-site portion of the wetland is part of a larger wetland that extends off-site to the north and south, Vegetation within the on-site portion of the wetland at the time of the site visit consisted of a palustrine forested plant community that included red alder (Alnus rubra), willow (Salix sp.), Oregon ash (Fraxinus latifolia), red -osier dogwood (Cornus sericea), salmonberry (Rebus spectabilis), black twinberry (Lonicera involucrata), spirea (Spiraea douglash), slough sedge (Carex obnupta), and mannagrass (Glyceria sp.). At the time of the field investigation, most of the on-site wetland contained several inches of ponded water. Soils throughout the non-ponded portions of the wetland were generally saturated to the surface. In addition, some sheet flow within the southeast portion of the wetland was observed draining south. Attachment A contains data sheets prepared for a representative location in both the wetland and upland. These data sheets document the vegetation, soils, and hydrology information that aided in the wetland boundary determination. Jack Zheng July 6, 2010 Page 2 Wetland A appears to meet the criteria for a Category 2 wetland per RMC 4-3- 050M.1.a.ii.d and would require a standard 50 -foot buffer per RMC 4-3-050M.6.c. Proposed Buffer Averaging The project proposes to utilize wetland buffer averaging. Wetland buffer averaging may be allowed by the City of Renton if all of the following provisions of RMC 4-3- 050M.6.f are met: That the wetland contains variations in ecological sensitivity or there are existing physical improvements in or near the wetland and buffer; and The area in the vicinity of the proposed buffer reduction currently consists primarily of Himalayan blackberry (Rebus discolor), trash, and yard debris and does not provide any significant habitat value to the wetland. The area in the vicinity of the proposed buffer replacement is generally forested with a native plant community of red alder, big -leaf maple (Acer macrophyllum), hazelnut (Corylus cornuta), thimbleberry (Rubes perviflorus), sword fern (Polystichum munitum), and fringecup (Tellima grandiflora). ii. That width averaging will not adversely impact the wetland function and values; and Since the proposed buffer reduction area is dominated by Himalayan blackberry, a non-native invasive species, and is not currently providing a significant habitat or water quality function, there should not be an adverse impact to any wetland functions. Furthermore, since the proposed buffer replacement area consists of a more diverse native plant community, there should be an overall increase in the habitat value of the buffer following averaging. iii. That the total area contained within the wetland buffer after averaging is no less than that contained within the required standard buffer prior to averaging; and Under the proposed buffer averaging plan, 428 s.f. of buffer area would be reduced and replaced with 467 st of additional buffer area for a total buffer increase of 39 s.f.. iv. A site specific evaluation and documentation of buffer adequacy based upon The Science of Wetland Buffers and its implications for the Management of Wetlands, McMillan 2000, or similar approaches have been conducted. The proposed buffer standard is based on consideration of the best available science as described in WAC 365-995-905; or where there is an absence of valid scientific information, the steps in RMC 4-9-25OF are followed. Jack Zheng July 6, 2010 Page 3 The proposed buffer averaging plan would increase both the overall size and habitat value of the buffer over current conditions and is consistent with best available science. v. In no instance shall the buffer width be reduced by more than fifty percent (505,o') of the standard buffer or be less than twenty five feet (25) wide. Greater buffer width reductions require review as a variance per subsection N3 of this Section and RMC 4-9-25OB; and Under the proposed buffer averaging plan, the minimum buffer width would be 29 feet and would not be reduced by more than 50% of the standard buffer. vi. Buffer enhancement in the areas where the buffer is reduced shall be required on a case-by-case basis where appropriate to site conditions, wetland sensitivity, and proposed land development characteristics. Since the remaining buffer in the vicinity of the proposed buffer reduction consists of a native forest there should be no need for additional plantings. vii. Notification may be required pursuant to subsection FS of this Section. Provision noted. If you have any questions regarding the wetland delineation or proposed buffer averaging plan, please give me a call. Sincerely, ALTMANN OLIVER ASSOCIATES, LLC . L John Altmann Ecologist Attachments ATTACHMENT A DATA SHEETS -T P 3l, j '- 10 f tMp I Lal t --T UA r•l 17 A k A -"-f �. DATA FORM ROU-nNE ONSITE DETERMINATION METHOt31 Field Investigator(sj: L< -T 0.4,,S Da1B; S-�(P - t o Project/Sita: 'rOA Slate; LAJq County-, 15 1 J Applicant/Owner; lel ini UR Plant Community 4/14ama: _ Note: K a more detailed site description is necessary, use the back of data form or a field notebook. Do normal environmental conditions exist at the plant community? _ - - - r `- _ _ _ _ _ , _ Yes 9 No _- - (if. no, explain on bacik) Has the vegetation, soils, and/or hydrology bean significantly disturbed? `fes... -- ----- _.....Nb- --........ yes, exp arrr on b a ) VEGETATION Indicator Indicator Dominant Plant Species Status Stratum Darninant Plant Species Slalus Stratum 1. Aln�rs rub n ,. +-Ar~ -T- 11. 2, e -t: n 145IaE Cul -r g. CocnJ ertces t;�tA 4, =M.rs �c F461 i s r -k C•! $ 14. 5. E 7. 17. 8. 18. g. 19. 10. i}0. Percent of dominant species that are O8L, FACW, and/or -FAC I DQ ''C' fs the hydrophytic vegaiallon criterion +net? Yss x No Rationale; TES SOILS Series/phase; Subgroup:2 Is the sail on the hydric soils f€st7 Yes _ No Undetermined Is the soil a Hlstosof? Yes _ - No Hisl€c_ p -$;don present? Yes No x_ Is the soil: h+WIfed? Yes No x_ Gfayed? Yes No x Matr€x Color; _ Mottle Calors: Other hydric soil indicators: Is the hydric soil criterion met? Yes X No Rationale: LOVA G f ozo,%& HYDROLOGY +r Is the ground surface fnundaled? Yes X No Surface water depth: I Is the soil saturated? Yes No Depth to free-standing water In p€t(sofl probe hole: List other field evidence of surface inundation or soil saturallon. Is the wetland hydrology criterion mel? Yes _ No Rationale- Osap.gklt4-A .f t1R15DICTIOHAL DETERMINATION AND. RATIONALE Is the plant community a watiand? Yes x No Rationale for`jurisdictianal declsfon: Lk- 3 s-Entre&tAMir I This data form can ba used for the Hydric Soil Assessment Procedure and the Plant CommunAy Assessrrrenl Procedure. _ 2Classftation according to'Soil Taxonomy.' 4 #,2. -, 1n' 1r..s i C-�- V'Q�A,,J9 A—`f w. DATA FO R M ROUTINE ONSITE DETERMINATION METHODZ Fleld lnvestigalor(s): _AI -T t A a-1� Date, lo Project/She.-- State: � r County; Applicant/Ownar: ?- EW -r l oz Plani Community vName: Note; 9 a more detailed site description is necessary, use'the back of data form or a field notebook. Do normal environmental conditions exist at the plant community? - Yes -A _ No , (If no, explain on back) Has the vegetation, soils, and/or hydrology been significantly disturbed? -- - _- -- ........... ..... .... X I y - - as o es, ax Iain -on- 6ac1c VEGETATION SOILS Saries/phase: Subgroup:2 Is the soil on the hydric soils list? Yes No Undetermined Is the soil a Histosol? Yes- No. K Hislic apipedon present? Yes No K Is the soil: k4ottlad? Yes No _X Gleyed? Yes No. Matrlx Color: 10 14L V3 Matila Colors: Other hydric soil Indfcators: Is the hydric soil criterion met? Yes No �c _ Rationale: HYDROLOGY Is the ground surface Inundated? Yes No Y, Surface water depth: Is the soil saturated? Yes No CX Depth 10 free-standing water In pVsoll probe hofs: List other field evidance of surface Inundation or soil saturation, Is the wetland hydrology criterion met? Yes No X Rationale: OUQ OP- f-4NI OCC Orr wAbi.16 r, J -1v4 JURISDICT10NAL DETERMINATiON AND, RATIONALE Is the plant community a wetland? Yes NO- CX Rationale for'jurlsd[Wonal decision; This data form can ba used for the Hydric Soil Assessment Procedure and the Plant Common ty Assessment Procedure. 2GlassO--alion according Io'SoilTaxonomy,' B-2 Indicalor Indicator dominant Plant Species Status Stratum Dominant Plant Speclas stalus Stralum 1. A In n robe-, _ T 11. 2. CvW-is c cr�kC �'11C j 512. 3. t� 1�+r �� C sus" wf1 CO ST 13. ----- - 4. - AVC�j 5 14. - - - 5.+ Js errs r ^ u S .._..._ Wit~ B. 7. 17. 8. is. 9, 19. 10. 20, Percent of dominant species that are OBL. FACW, and/or -FAC z0°It. Is the hydrophytic vagetation criterion mat? Yes No -X Nationale; SOILS Saries/phase: Subgroup:2 Is the soil on the hydric soils list? Yes No Undetermined Is the soil a Histosol? Yes- No. K Hislic apipedon present? Yes No K Is the soil: k4ottlad? Yes No _X Gleyed? Yes No. Matrlx Color: 10 14L V3 Matila Colors: Other hydric soil Indfcators: Is the hydric soil criterion met? Yes No �c _ Rationale: HYDROLOGY Is the ground surface Inundated? Yes No Y, Surface water depth: Is the soil saturated? Yes No CX Depth 10 free-standing water In pVsoll probe hofs: List other field evidance of surface Inundation or soil saturation, Is the wetland hydrology criterion met? Yes No X Rationale: OUQ OP- f-4NI OCC Orr wAbi.16 r, J -1v4 JURISDICT10NAL DETERMINATiON AND, RATIONALE Is the plant community a wetland? Yes NO- CX Rationale for'jurlsd[Wonal decision; This data form can ba used for the Hydric Soil Assessment Procedure and the Plant Common ty Assessment Procedure. 2GlassO--alion according Io'SoilTaxonomy,' B-2 0 FA i 4 A S N `n -n z M rn z d rn Altmann Oliver Associates, LLC I AOA FIOURF I: BUFFER AVFRAOINO PLAN WF5T PACIFIC, 5HORT FLAT 64456 IOQTH AVE. 5E RENTON, WA5WK&TON PARCEL a0O8800-04g5 DPA" 1/1 SECTION 7 OTHER PERMITS SECTION 8 ESC ANALYSIS AND DESIGN SECTION 9 BOND QUANTITIES, FACILITY SUMMARIES, AND DECLARATION OF COVENANT SECTION 10 OPERATIONS AND MAINTENANCE MANUAL