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HomeMy WebLinkAboutItem 26 PSE_Talbot_SW basin memo_2016_1104_combinedTechnical Memorandum K:\project\31900\31983H\ProjectDocs\Reports\Stormwater pond tech memo\PSE_Talbot_SW pond memo_2016_1104.docx 11241Willows Road NE Suite 200 Redmond, WA 98052 Phone (425) 822-4446 Fax (425) 827-9577 Otak was hired by Puget Sound Energy (PSE) to evaluate the existing stormwater basin at the Talbot Hill Substation for the presence/absence of wetlands and assess potential regulatory jurisdiction. The U.S. Army Corps of Engineers (USACE) regulates wetlands under Section 404 of the Clean Water Act (CWA), and the City of Renton (Renton) regulates wetlands under Section 4-3- 050 (Critical Areas Regulations) of the Renton Municipal Code (RMC). The existing stormwater basin is proposed to be regraded and expanded to support drainage and facility improvements at the substation. This technical memorandum summarizes the findings of the background research and field survey, and addresses regulatory jurisdiction of the stormwater basin and expansion area regarding wetlands and other aquatic habitats. The Talbot Hill Substation is located in the City of Renton, King County, Washington. A map of the review area (Figure 1), ground level photographs, and wetland determination data forms are included as attachments. The review area included the project area (proposed limit of disturbance) plus 200 feet to assess potential impacts to aquatic resources beyond the project area boundaries. No jurisdictional wetlands or other aquatic resources were observed in the review area as documented in this technical memorandum. Methods Methods for determining the presence/absence of wetlands in the project area included a review of available published information and a field investigation by an Otak biologist. The review area for this study included the project area shown on Figure 1 plus 200-feet in accordance with RMC Chapter 4-3-050-F.2(e)i. To: Jeff McMeekin Puget Sound Energy From: Jeff Gray, Senior Wetland Biologist Copies: File Date: November 4, 2016 Subject: Regulatory assessment of existing stormwater basin at the PSE Talbot Hill Substation - Renton, Washington Project No.: 31983.H Jeff McMeekin, Puget Sound Energy Page 2 Talbot Hill Substation – Stormwater Basin Review Memo November 4, 2016 K:\project\31900\31983H\ProjectDocs\Reports\Stormwater pond tech memo\PSE_Talbot_SW pond memo_2016_1104.docx 1. Background Review Available published information was reviewed prior to the field effort to identify any previously documented wetlands, streams, or other site characteristics (e.g., vegetation community patterns, topography, soils, or water courses) that would indicate the presence of wetlands within and around the project area. These maps are typically used as guidance, and do not supersede conditions in the field. The following sources were reviewed as part of this effort: • RMC Chapter 4-3-050 (Critical Areas Regulations). • King County iMap, accessed at http://www.kingcounty.gov/operations/GIS/Maps/iMAP.aspx on October 28, 2016. • Renton’s COR Maps - GIS mapping data, accessed at http://rp.rentonwa.gov/SilverlightPublic/Viewer.html?Viewer=COR-Maps • Renton’s Surface Water Classifications and Wetlands Map, accessed at http://rentonwa.gov/uploadedFiles/Government/FIT/GIS/PDF_Files/WaterClass%20and% 20Wetlands_22x34_reduced.pdf • Renton’s Surface Water Network Map, accessed at http://rentonwa.gov/uploadedFiles/Government/FIT/GIS/PDF_Files/Surfacewater%20Net work(1).pdf • Washington State Department of Fish and Wildlife (WDFW) Salmonscape mapping data, accessed at http://apps.wdfw.wa.gov/salmonscape/map.html • WDFW Priority Habitat and Species (PHS) mapping data, accessed at http://apps.wdfw.wa.gov/phsontheweb/ • Washington Department of Natural Resources (WDNR) Forest Practices Application Mapping Tool, accessed at https://fortress.wa.gov/dnr/protectiongis/fpamt/default.aspx • National Wetland Inventory (NWI) mapping data, accessed at https://www.fws.gov/wetlands/data/mapper.html • Natural Resources Conservation Service (NRCS) Web Soils Survey mapping data, accessed at http://websoilsurvey.sc.egov.usda.gov/App/HomePage.htm • Washington Department of Natural Resources (WDNR) Natural Heritage Program data, accessed at http://file.dnr.wa.gov/publications/amp_nh_trs.pdf; and, • Aerial photo of the vicinity using public web-based mapping service (Google Earth Pro) on October 28, 2016. Soil units mapped within the review area include: 1) Alderwood gravelly sandy loam, 8 to 15 percent slopes, and 2) Arents, Alderwood material, 6 to 15 percent slopes (Table 1-1). The majority (approximately 95%) of the study area is mapped as Alderwood gravelly sandy loam. Neither of the two soil units mapped in the review area are listed as hydric by NRCS. Both soil units are classified as moderately well drained. Jeff McMeekin, Puget Sound Energy Page 3 Talbot Hill Substation – Stormwater Basin Review Memo November 4, 2016 K:\project\31900\31983H\ProjectDocs\Reports\Stormwater pond tech memo\PSE_Talbot_SW pond memo_2016_1104.docx NWI wetlands are not mapped in the review area, and Renton does not indicate any surface waters (streams or wetlands) occurring within the review area. No streams or wetlands are mapped in the review area or vicinity by WDNR, WDFW, and King County online resources listed above. The project is located at approximately 410 feet above mean sea level on the top of a ridge that separates the Lower Cedar River watershed [Water Resource Inventory (WRIA) 8: Cedar- Sammamish] and the Lower Duwamish River watershed (WRIA 9: Duwamish-Green). 2. Field Investigation In accordance with federal, state, and local requirements, the review area was surveyed in the field for the presence of wetlands using the three-parameter approach detailed in the Corps of Engineers Wetlands Delineation Manual (USACE, 1987), and the Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Western Mountains, Valleys, and Coast Region (Version 2.0) (USACE, 2010). Following routine methodology, data on vegetation, soils, and hydrology were recorded on USACE wetland determination data forms at four data points to document site conditions. Data point locations are shown on Figure 1. Data points were located in the field at topographic low points (i.e., depressions) in the review area where wetlands would most likely occur. Soils Hydric soils are defined as soils that are saturated, flooded, or ponded long enough during the growing season to develop anaerobic conditions in the upper part of the soil profile (USACE 2010). Soil samples were obtained at representative data points by digging a pit to a depth of at least 18 inches to determine the presence or absence of hydric soil indicators using the Field Indicators of Hydric Soils In the United States, Version 7.0 (NRCS 2010). Soil colors were evaluated against a Munsell® soil color chart (Gretag/Macbeth 2000) to distinguish hydric from non-hydric soils. Hydrology Wetland hydrologic conditions are considered present if, during the growing season, an area has 14 or more consecutive days of flooding or ponding; or a water table 12 inches or less below the soil surface, during the growing season at a minimum frequency of 5 years in 10, depending on soil and plant community conditions (USACE 2010). Primary and secondary wetland hydrology indicators were also used to evaluate the presence or absence of wetland hydrology at each data point. Vegetation Representative vegetation communities were documented at four data points during the field survey to determine the presence or absence of hydrophytic vegetation indicators. At each data point, three strata were inventoried, including trees within a 30-foot diameter plot, shrubs within a 15-foot diameter plot, and non-woody herbaceous plants within a 5-foot diameter plot. Plant species in each stratum were identified and the percent cover recorded. Each species was listed following the Jeff McMeekin, Puget Sound Energy Page 4 Talbot Hill Substation – Stormwater Basin Review Memo November 4, 2016 K:\project\31900\31983H\ProjectDocs\Reports\Stormwater pond tech memo\PSE_Talbot_SW pond memo_2016_1104.docx scientific nomenclature given in the United States Department of Agriculture (USDA) PLANTS database (NRCS 2016). The wetland indicator status for each species was assigned using the 2016 National Wetland Plant List for the Western Mountains, Valleys & Coast Region (Lichvar et al. 2016). Findings - Existing Conditions No federally or locally regulated wetlands or streams or their buffers are located within the review area. Four data points were recorded at topographical low areas to document upland habitats as shown on Figure 1. The following includes a description of the existing conditions of the existing stormwater basin and proposed expansion area. The existing stormwater basin was originally constructed in the 1990’s, and is now overgrown with vegetation dominated by Himalayan blackberry (Rubus armeniacus) with a few black cottonwood (Populus trichocarpa) trees. The upland vegetation community on the side slopes and basin edges consists of red alder (Alnus rubra), big leaf maple (Acer macrophyllum), beaked hazelnut (Corylus cornuta), Himalayan blackberry, and swordfern (Ploystichum munitum). The basin soils were dry to a depth of 18 inches at the time of the site visit, and had 10YR 3/2 and 10YR 3/3 dominant matrices with no redoximorphic features. Data points #1 and #2 document the upland site conditions in the basin. The stormwater basin is a linear depression located on the south side of the fenced-in substation between the substation and a gravel access road. A perched discharge/inlet pipe is located on the north side of the stormwater basin that was originally intended to drain the substation yard, but no flows were observed or appeared to have occurred recently. The stormwater basin did not appear to be functioning as there was no observable evidence that it is currently receiving or discharging stormwater. There was a record amount of rainfall for the month of October 2016, but there were no signs of prolonged inundation (e.g., stained leaves) or flow paths (e.g., scour, gravel sorting, erosion) to or from the inlet and outlet pipes. No herbaceous plants were observed due to the dense Himalayan blackberry cover and leaf litter. Per the land survey for the project, there is an outlet pipe from the stormwater basin that discharges to the southside of the access road within a transmission line right of way (ROW). The pipe outfalls into an isolated depression that was likely used as a gravel pit to construct the access road embankment. This pipe was not found in the field. Vegetation in the depression is dominated by reed canarygrass (Phalaris arundinacea). Soils were dry to a depth of 20 inches at the time of the site visit, and had 10YR 3/2 and 10YR 4/3 dominant matrices with no redoximorphic features. Data point #3 documents the upland site conditions at the topographical low point in the vicinity of the surveyed outfall location. Jeff McMeekin, Puget Sound Energy Page 5 Talbot Hill Substation – Stormwater Basin Review Memo November 4, 2016 K:\project\31900\31983H\ProjectDocs\Reports\Stormwater pond tech memo\PSE_Talbot_SW pond memo_2016_1104.docx The proposed expansion area northeast of the existing stormwater basin includes upland forest habitat with a canopy of big leaf maple and Douglas-fir (Psuedotsuga menziesii) trees. The understory consisted of salal (Gaultheria shallon), vine maple (Acer circinatum), snowberry (Symphoricarpos ablus), beaked hazelnut and swordfern. Soils were dry to a depth of 20 inches at the time of the site visit, and had 10YR 3/2 and 10YR 3/3 dominant matrices with no redoximorphic features. Data point #4 documents the upland site conditions in the proposed expansion area. No wetlands or other aquatic resources were observed within 200 feet of the project area. A large Himalayan blackberry field abuts the project area to the north and east, and a transmission line ROW parallels the project area to the south beyond the gravel access road. Upland forest vegetation in and near the ROW includes big leaf maple, red alder, beaked hazelnut, orchard grass (Dactylis glomerata), reed canarygrass, and bentgrass (Agrostis sp.). No areas of surface ponding or saturated/muddy soils were observed within the ROW. A linear patch of upland forest slopes downhill away from and west of the project area near the gated entrance. The fenced-in Talbot Hill Substation yard is located north and west of the project area. Additionally, no habitat conservation areas as defined at RMC Chapter 4-3-050-G.6 (Habitat Conservation Areas) are located within the review area, and no WDFW-listed Priority Habitats and Species are mapped in the review area. Regulatory Assessment of Proposed Action and Summary No wetlands or other aquatic resources regulated by the USACE under Section 404 of the CWA and by Renton under RMC Section 4-3-050 (Critical Areas Regulations) are located in the project area. The existing stormwater basin did not meet the definition of a regulatory wetland, and is therefore not regulated as such. No wetlands were observed in the project area or within 200 feet, and buffers from wetlands off-property therefore likely do not extend into the project area. Additionally, a review of available published information (Renton’s COR GIS Maps, King County iMap, NWI, WDNR online resources, WDFW PHS maps, and NRCS soils map) did not indicate the presence of wetlands or other aquatic resources in the review area. PSE Talbot Substation - Wetlands Presence/Absence Study Review area limits and data point locations. Legend 100 m N➤➤N © 2016 Google © 2016 Google © 2016 Google Ground Level Photographs of Project Area Puget Sound Energy Talbot Hill Substation 1 November 4, 2016 Stormwater Facility Review Memo Photo 1: View facing south of Data Point #1 in the abandoned stormwater basin overgrown with Himalayan blackberry (Rubus armeniacus). The inlet pipe is shown at the bottom-center of the photo. Photo 2: Photo of upland forest habitat at Data Point #2 in the abandoned stormwater basin. Ground Level Photographs of Project Area Puget Sound Energy Talbot Hill Substation 2 November 4, 2016 Stormwater Facility Review Memo Photo 3: View facing east of the meadow at Data Point #3 within the transmission line ROW. Photo 4: View facing south of upland forest habitat at Data Point #4 in the proposed stormwater basin expansion area. US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 WETLAND DETERMINATION DATA FORM – Western Mountains, Valleys, and Coast Region VEGETATION – Use scientific names of plants Tree Stratum (Plot size: 30' diameter) Absolute % Cover Dominant Species? Indicator Status Dominance Test Worksheet: 1. - Number of Dominant Species That Are OBL, FACW, or FAC: 1 (A) 2. 3. Total Number of Dominant Species Across All Strata: 1 (B) 4. 50% = , 20% = = Total Cover Percent of Dominant Species That Are OBL, FACW, or FAC: 100 (A/B) Sapling/Shrub Stratum (Plot size: 15' diameter) 1. Rubus armeniacus 90 yes FAC Prevalence Index worksheet: 2. Corylus cornuta 10 no FACU Total % Cover of: Multiply by: 3. OBL species x1 = 4. FACW species x2 = 5. FAC species x3 = 50% = 50, 20% = 20 100 = Total Cover FACU species x4 = Herb Stratum (Plot size: 5' diameter) UPL species x5 = 1. - Column Totals: (A) (B) 2. Prevalence Index = B/A = 3. Hydrophytic Vegetation Indicators: 4. 1 – Rapid Test for Hydrophytic Vegetation 5. 2 - Dominance Test is >50% 6. 3 - Prevalence Index is <3.01 7. 4 - Morphological Adaptations1 (Provide supporting data in Remarks or on a separate sheet) 8. 9. 5 - Wetland Non-Vascular Plants1 10. Problematic Hydrophytic Vegetation1 (Explain) 11. 1Indicators of hydric soil and wetland hydrology must be present, unless disturbed or problematic. 50% = , 20% = = Total Cover Woody Vine Stratum (Plot size: 10' diameter) 1. - Hydrophytic Vegetation Present? Yes No 2. 50% = , 20% = = Total Cover % Bare Ground in Herb Stratum 100 Remarks: No hydrophytic vegetation indicator present. 100% bare ground due in herbaceous layer due to dense blackberry cover. Project Site: PSE - Talbot Hill Substation City/County: Renton/King Sampling Date: 11/1/16 Applicant/Owner: PSE State: WA Sampling Point: 1 Investigator(s): Jeff Gray Section, Township, Range: S20, T23 N, R5 E Landform (hillslope, terrace, etc.): depression Local relief (concave, convex, none): concave Slope (%): 0-2 Subregion (LRR): A Lat: - Long: - Datum: - Soil Map Unit Name: Alderwood gravelly sandy loam, 8 to 15 percent slopes NWI classification: None Are climatic / hydrologic conditions on the site typical for this time of year? Yes No (If no, explain in Remarks.) Are Vegetation , Soil , or Hydrology , significantly disturbed? Are “Normal Circumstances” present? Yes No Are Vegetation , Soil , or Hydrology , naturally problematic? (If needed, explain any answers in Remarks.) SUMMARY OF FINDINGS – Attach site map showing sampling point locations, transects, important features, etc. Hydrophytic Vegetation Present? Yes No Is the Sampled Area within a Wetland? Yes No Hydric Soil Present? Yes No Wetland Hydrology Present? Yes No Remarks: Not all three wetland indicators present. Data point located near outfall pipe at lowest point in abandoned stormwater basin. US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 SOIL Sampling Point: 1 Profile Description: (Describe to the depth needed to document the indicator or confirm the absence of indicators.) Depth Matrix Redox Features (inches) Color (moist) % Color (moist) % Type1 Loc2 Texture Remarks 0-18 10YR 3/2 90 loam gravels; dry 10YR 3/3 10 1Type: C= Concentration, D=Depletion, RM=Reduced Matrix, CS=Covered or Coated Sand Grains. 2Location: PL=Pore Lining, M=Matrix Hydric Soil Indicators: (Applicable to all LRRs, unless otherwise noted.) Indicators for Problematic Hydric Soils3: Histosol (A1) Sandy Redox (S5) 2 cm Muck (A10) Histic Epipedon (A2) Stripped Matrix (S6) Red Parent Material (TF2) Black Histic (A3) Loamy Mucky Mineral (F1) (except MLRA 1) Very Shallow Dark Surface (TF12) Hydrogen Sulfide (A4) Loamy Gleyed Matrix (F2) Other (Explain in Remarks) Depleted Below Dark Surface (A11) Depleted Matrix (F3) 3Indicators of hydrophytic vegetation and wetland hydrology must be present, unless disturbed or problematic. Thick Dark Surface (A12) Redox Dark Surface (F6) Sandy Mucky Mineral (S1) Depleted Dark Surface (F7) Sandy Gleyed Matrix (S4) Redox Depressions (F8) Restrictive Layer (if present): Hydric Soils Present? Yes No Type: Depth (inches): Remarks: No hydric soil indicators present. HYDROLOGY Wetland Hydrology Indicators: Primary Indicators (minimum of one required; check all that apply) Secondary Indicators (2 or more required) Surface Water (A1) Water-Stained Leaves (B9) Water-Stained Leaves (B9) High Water Table (A2) (except MLRA 1, 2, 4A, and 4B) (MLRA 1, 2, 4A, and 4B) Saturation (A3) Salt Crust (B11) Drainage Patterns (B10) Water Marks (B1) Aquatic Invertebrates (B13) Dry-Season Water Table (C2) Sediment Deposits (B2) Hydrogen Sulfide Odor (C1) Saturation Visible on Aerial Imagery (C9) Drift Deposits (B3) Oxidized Rhizospheres along Living Roots (C3) Geomorphic Position (D2) Algal Mat or Crust (B4) Presence of Reduced Iron (C4) Shallow Aquitard (D3) Iron Deposits (B5) Recent Iron Reduction in Tilled Soils (C6) FAC-Neutral Test (D5) Surface Soil Cracks (B6) Stunted or Stresses Plants (D1) (LRR A) Raised Ant Mounds (D6) (LRR A) Inundation Visible on Aerial Imagery (B7) Other (Explain in Remarks) Frost-Heave Hummocks (D7) Sparsely Vegetated Concave Surface (B8) Field Observations: Surface Water Present? Yes No Depth (inches): Wetland Hydrology Present? Yes No Water Table Present? Yes No Depth (inches): Saturation Present? (includes capillary fringe) Yes No Depth (inches): Describe Recorded Data (stream gauge, monitoring well, aerial photos, previous inspections), if available: Remarks: No primary indicators of wetland hydrology present. Area dry despite record rainfall for month of October 2016. Project Site: PSE - Talbot Hill Substation US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 WETLAND DETERMINATION DATA FORM – Western Mountains, Valleys, and Coast Region VEGETATION – Use scientific names of plants Tree Stratum (Plot size: 30' diameter) Absolute % Cover Dominant Species? Indicator Status Dominance Test Worksheet: 1. Acer macrophyllum 35 yes FACU Number of Dominant Species That Are OBL, FACW, or FAC: 1 (A) 2. Populus trichocarpa 7 no FAC 3. Pseudotsuga menziesii 25 yes FACU Total Number of Dominant Species Across All Strata: 5 (B) 4. 50% = 33.5, 20% = 13.4 67 = Total Cover Percent of Dominant Species That Are OBL, FACW, or FAC: 20 (A/B) Sapling/Shrub Stratum (Plot size: 15' diameter) 1. Rubus armeniacus 15 yes FAC Prevalence Index worksheet: 2. Corylus cornuta 15 yes FACU Total % Cover of: Multiply by: 3. OBL species x1 = 4. FACW species x2 = 5. FAC species x3 = 50% = 15, 20% = 6 30 = Total Cover FACU species x4 = Herb Stratum (Plot size: 5' diameter) UPL species x5 = 1. Polystichum munitum 10 yes FACU Column Totals: (A) (B) 2. Prevalence Index = B/A = 3. Hydrophytic Vegetation Indicators: 4. 1 – Rapid Test for Hydrophytic Vegetation 5. 2 - Dominance Test is >50% 6. 3 - Prevalence Index is <3.01 7. 4 - Morphological Adaptations1 (Provide supporting data in Remarks or on a separate sheet) 8. 9. 5 - Wetland Non-Vascular Plants1 10. Problematic Hydrophytic Vegetation1 (Explain) 11. 1Indicators of hydric soil and wetland hydrology must be present, unless disturbed or problematic. 50% = 5, 20% = 2 10 = Total Cover Woody Vine Stratum (Plot size: 10' diameter) 1. - Hydrophytic Vegetation Present? Yes No 2. 50% = , 20% = = Total Cover % Bare Ground in Herb Stratum 90 (leaf litter, rocks) Remarks: No hydrophytic vegetation indicator present. Project Site: PSE - Talbot Hill Substation City/County: Renton/King Sampling Date: 11/1/16 Applicant/Owner: PSE State: WA Sampling Point: 2 Investigator(s): Jeff Gray Section, Township, Range: S20, T23 N, R5 E Landform (hillslope, terrace, etc.): depression Local relief (concave, convex, none): concave Slope (%): 2-5 Subregion (LRR): A Lat: - Long: - Datum: - Soil Map Unit Name: Alderwood gravelly sandy loam, 8 to 15 percent slopes NWI classification: None Are climatic / hydrologic conditions on the site typical for this time of year? Yes No (If no, explain in Remarks.) Are Vegetation , Soil , or Hydrology , significantly disturbed? Are “Normal Circumstances” present? Yes No Are Vegetation , Soil , or Hydrology , naturally problematic? (If needed, explain any answers in Remarks.) SUMMARY OF FINDINGS – Attach site map showing sampling point locations, transects, important features, etc. Hydrophytic Vegetation Present? Yes No Is the Sampled Area within a Wetland? Yes No Hydric Soil Present? Yes No Wetland Hydrology Present? Yes No Remarks: Not all three wetland indicators present. Data point located near outfall pipe at eastern edge of abandoned stormwater basin. US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 SOIL Sampling Point: 2 Profile Description: (Describe to the depth needed to document the indicator or confirm the absence of indicators.) Depth Matrix Redox Features (inches) Color (moist) % Color (moist) % Type1 Loc2 Texture Remarks 0-16 10YR 2/2 100 loam gravels; dry 16-20+ 10YR 3/3 100 loam gravels; dry 1Type: C= Concentration, D=Depletion, RM=Reduced Matrix, CS=Covered or Coated Sand Grains. 2Location: PL=Pore Lining, M=Matrix Hydric Soil Indicators: (Applicable to all LRRs, unless otherwise noted.) Indicators for Problematic Hydric Soils3: Histosol (A1) Sandy Redox (S5) 2 cm Muck (A10) Histic Epipedon (A2) Stripped Matrix (S6) Red Parent Material (TF2) Black Histic (A3) Loamy Mucky Mineral (F1) (except MLRA 1) Very Shallow Dark Surface (TF12) Hydrogen Sulfide (A4) Loamy Gleyed Matrix (F2) Other (Explain in Remarks) Depleted Below Dark Surface (A11) Depleted Matrix (F3) 3Indicators of hydrophytic vegetation and wetland hydrology must be present, unless disturbed or problematic. Thick Dark Surface (A12) Redox Dark Surface (F6) Sandy Mucky Mineral (S1) Depleted Dark Surface (F7) Sandy Gleyed Matrix (S4) Redox Depressions (F8) Restrictive Layer (if present): Hydric Soils Present? Yes No Type: Depth (inches): Remarks: No hydric soil indicators present. HYDROLOGY Wetland Hydrology Indicators: Primary Indicators (minimum of one required; check all that apply) Secondary Indicators (2 or more required) Surface Water (A1) Water-Stained Leaves (B9) Water-Stained Leaves (B9) High Water Table (A2) (except MLRA 1, 2, 4A, and 4B) (MLRA 1, 2, 4A, and 4B) Saturation (A3) Salt Crust (B11) Drainage Patterns (B10) Water Marks (B1) Aquatic Invertebrates (B13) Dry-Season Water Table (C2) Sediment Deposits (B2) Hydrogen Sulfide Odor (C1) Saturation Visible on Aerial Imagery (C9) Drift Deposits (B3) Oxidized Rhizospheres along Living Roots (C3) Geomorphic Position (D2) Algal Mat or Crust (B4) Presence of Reduced Iron (C4) Shallow Aquitard (D3) Iron Deposits (B5) Recent Iron Reduction in Tilled Soils (C6) FAC-Neutral Test (D5) Surface Soil Cracks (B6) Stunted or Stresses Plants (D1) (LRR A) Raised Ant Mounds (D6) (LRR A) Inundation Visible on Aerial Imagery (B7) Other (Explain in Remarks) Frost-Heave Hummocks (D7) Sparsely Vegetated Concave Surface (B8) Field Observations: Surface Water Present? Yes No Depth (inches): Wetland Hydrology Present? Yes No Water Table Present? Yes No Depth (inches): Saturation Present? (includes capillary fringe) Yes No Depth (inches): Describe Recorded Data (stream gauge, monitoring well, aerial photos, previous inspections), if available: Remarks: No primary indicators of wetland hydrology present. Area dry despite record rainfall for month of October 2016. Project Site: PSE - Talbot Hill Substation US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 WETLAND DETERMINATION DATA FORM – Western Mountains, Valleys, and Coast Region VEGETATION – Use scientific names of plants Tree Stratum (Plot size: 30' diameter) Absolute % Cover Dominant Species? Indicator Status Dominance Test Worksheet: 1. - Number of Dominant Species That Are OBL, FACW, or FAC: 2 (A) 2. 3. Total Number of Dominant Species Across All Strata: 2 (B) 4. 50% = , 20% = = Total Cover Percent of Dominant Species That Are OBL, FACW, or FAC: 100 (A/B) Sapling/Shrub Stratum (Plot size: 15' diameter) 1. Rubus armeniacus 10 yes FAC Prevalence Index worksheet: 2. Total % Cover of: Multiply by: 3. OBL species x1 = 4. FACW species x2 = 5. FAC species x3 = 50% = 5, 20% = 2 10 = Total Cover FACU species x4 = Herb Stratum (Plot size: 5' diameter) UPL species x5 = 1. Phalaris arundinacea 86 yes FACW Column Totals: (A) (B) 2. Agrostis capillaris 3 no FAC Prevalence Index = B/A = 3. Dactylis glomerata 8 no FACU Hydrophytic Vegetation Indicators: 4. Cirsium arvense 3 no FAC 1 – Rapid Test for Hydrophytic Vegetation 5. 2 - Dominance Test is >50% 6. 3 - Prevalence Index is <3.01 7. 4 - Morphological Adaptations1 (Provide supporting data in Remarks or on a separate sheet) 8. 9. 5 - Wetland Non-Vascular Plants1 10. Problematic Hydrophytic Vegetation1 (Explain) 11. 1Indicators of hydric soil and wetland hydrology must be present, unless disturbed or problematic. 50% = 50, 20% = 20 100 = Total Cover Woody Vine Stratum (Plot size: 10' diameter) 1. - Hydrophytic Vegetation Present? Yes No 2. 50% = , 20% = = Total Cover % Bare Ground in Herb Stratum 0 Remarks: No hydrophytic vegetation indicator present. Project Site: PSE - Talbot Hill Substation City/County: Renton/King Sampling Date: 11/1/16 Applicant/Owner: PSE State: WA Sampling Point: 3 Investigator(s): Jeff Gray Section, Township, Range: S20, T23 N, R5 E Landform (hillslope, terrace, etc.): depression Local relief (concave, convex, none): concave Slope (%): 2-5 Subregion (LRR): A Lat: - Long: - Datum: - Soil Map Unit Name: Alderwood gravelly sandy loam, 8 to 15 percent slopes NWI classification: None Are climatic / hydrologic conditions on the site typical for this time of year? Yes No (If no, explain in Remarks.) Are Vegetation , Soil , or Hydrology , significantly disturbed? Are “Normal Circumstances” present? Yes No Are Vegetation , Soil , or Hydrology , naturally problematic? (If needed, explain any answers in Remarks.) SUMMARY OF FINDINGS – Attach site map showing sampling point locations, transects, important features, etc. Hydrophytic Vegetation Present? Yes No Is the Sampled Area within a Wetland? Yes No Hydric Soil Present? Yes No Wetland Hydrology Present? Yes No Remarks: Not all three wetland indicators present. Data point located in depression south of access road south of abandoned stormwater basin. US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 SOIL Sampling Point: 3 Profile Description: (Describe to the depth needed to document the indicator or confirm the absence of indicators.) Depth Matrix Redox Features (inches) Color (moist) % Color (moist) % Type1 Loc2 Texture Remarks 0-16 10YR 3/2 100 loam gravels; dry 16-20+ 10YR 4/3 100 loam dry 1Type: C= Concentration, D=Depletion, RM=Reduced Matrix, CS=Covered or Coated Sand Grains. 2Location: PL=Pore Lining, M=Matrix Hydric Soil Indicators: (Applicable to all LRRs, unless otherwise noted.) Indicators for Problematic Hydric Soils3: Histosol (A1) Sandy Redox (S5) 2 cm Muck (A10) Histic Epipedon (A2) Stripped Matrix (S6) Red Parent Material (TF2) Black Histic (A3) Loamy Mucky Mineral (F1) (except MLRA 1) Very Shallow Dark Surface (TF12) Hydrogen Sulfide (A4) Loamy Gleyed Matrix (F2) Other (Explain in Remarks) Depleted Below Dark Surface (A11) Depleted Matrix (F3) 3Indicators of hydrophytic vegetation and wetland hydrology must be present, unless disturbed or problematic. Thick Dark Surface (A12) Redox Dark Surface (F6) Sandy Mucky Mineral (S1) Depleted Dark Surface (F7) Sandy Gleyed Matrix (S4) Redox Depressions (F8) Restrictive Layer (if present): Hydric Soils Present? Yes No Type: Depth (inches): Remarks: No hydric soil indicators present. HYDROLOGY Wetland Hydrology Indicators: Primary Indicators (minimum of one required; check all that apply) Secondary Indicators (2 or more required) Surface Water (A1) Water-Stained Leaves (B9) Water-Stained Leaves (B9) High Water Table (A2) (except MLRA 1, 2, 4A, and 4B) (MLRA 1, 2, 4A, and 4B) Saturation (A3) Salt Crust (B11) Drainage Patterns (B10) Water Marks (B1) Aquatic Invertebrates (B13) Dry-Season Water Table (C2) Sediment Deposits (B2) Hydrogen Sulfide Odor (C1) Saturation Visible on Aerial Imagery (C9) Drift Deposits (B3) Oxidized Rhizospheres along Living Roots (C3) Geomorphic Position (D2) Algal Mat or Crust (B4) Presence of Reduced Iron (C4) Shallow Aquitard (D3) Iron Deposits (B5) Recent Iron Reduction in Tilled Soils (C6) FAC-Neutral Test (D5) Surface Soil Cracks (B6) Stunted or Stresses Plants (D1) (LRR A) Raised Ant Mounds (D6) (LRR A) Inundation Visible on Aerial Imagery (B7) Other (Explain in Remarks) Frost-Heave Hummocks (D7) Sparsely Vegetated Concave Surface (B8) Field Observations: Surface Water Present? Yes No Depth (inches): Wetland Hydrology Present? Yes No Water Table Present? Yes No Depth (inches): Saturation Present? (includes capillary fringe) Yes No Depth (inches): Describe Recorded Data (stream gauge, monitoring well, aerial photos, previous inspections), if available: Remarks: No primary indicators of wetland hydrology present. Area dry despite record rainfall for month of October 2016. Project Site: PSE - Talbot Hill Substation US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 WETLAND DETERMINATION DATA FORM – Western Mountains, Valleys, and Coast Region VEGETATION – Use scientific names of plants Tree Stratum (Plot size: 30' diameter) Absolute % Cover Dominant Species? Indicator Status Dominance Test Worksheet: 1. Acer macrophyllum 40 yes FACU Number of Dominant Species That Are OBL, FACW, or FAC: 0 (A) 2. Pseudotsuga menziesii 30 yes FACU 3. Total Number of Dominant Species Across All Strata: 4 (B) 4. 50% = 35, 20% = 14 70 = Total Cover Percent of Dominant Species That Are OBL, FACW, or FAC: 0 (A/B) Sapling/Shrub Stratum (Plot size: 15' diameter) 1. Gaultheria shallon 30 yes FACU Prevalence Index worksheet: 2. Corylus cornuta 10 no FACU Total % Cover of: Multiply by: 3. Acer circinatum 10 no FAC OBL species x1 = 4. Oemleria cerasiformis 5 no FACU FACW species x2 = 5. FAC species x3 = 50% = 27.5, 20% = 11 55 = Total Cover FACU species x4 = Herb Stratum (Plot size: 5' diameter) UPL species x5 = 1. Polystichum munitum 15 yes FACU Column Totals: (A) (B) 2. Prevalence Index = B/A = 3. Hydrophytic Vegetation Indicators: 4. 1 – Rapid Test for Hydrophytic Vegetation 5. 2 - Dominance Test is >50% 6. 3 - Prevalence Index is <3.01 7. 4 - Morphological Adaptations1 (Provide supporting data in Remarks or on a separate sheet) 8. 9. 5 - Wetland Non-Vascular Plants1 10. Problematic Hydrophytic Vegetation1 (Explain) 11. 1Indicators of hydric soil and wetland hydrology must be present, unless disturbed or problematic. 50% = 7.5, 20% = 3 15 = Total Cover Woody Vine Stratum (Plot size: 10' diameter) 1. - Hydrophytic Vegetation Present? Yes No 2. 50% = , 20% = = Total Cover % Bare Ground in Herb Stratum 85 (leaf litter) Remarks: No hydrophytic vegetation indicator present. Project Site: PSE - Talbot Hill Substation City/County: Renton/King Sampling Date: 11/1/16 Applicant/Owner: PSE State: WA Sampling Point: 4 Investigator(s): Jeff Gray Section, Township, Range: S20, T23 N, R5 E Landform (hillslope, terrace, etc.): depression Local relief (concave, convex, none): concave Slope (%): 2-5 Subregion (LRR): A Lat: - Long: - Datum: - Soil Map Unit Name: Alderwood gravelly sandy loam, 8 to 15 percent slopes NWI classification: None Are climatic / hydrologic conditions on the site typical for this time of year? Yes No (If no, explain in Remarks.) Are Vegetation , Soil , or Hydrology , significantly disturbed? Are “Normal Circumstances” present? Yes No Are Vegetation , Soil , or Hydrology , naturally problematic? (If needed, explain any answers in Remarks.) SUMMARY OF FINDINGS – Attach site map showing sampling point locations, transects, important features, etc. Hydrophytic Vegetation Present? Yes No Is the Sampled Area within a Wetland? Yes No Hydric Soil Present? Yes No Wetland Hydrology Present? Yes No Remarks: Not all three wetland indicators present. Data point located in proposed expansion area northeast of existing stormwater basin. US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 SOIL Sampling Point: 4 Profile Description: (Describe to the depth needed to document the indicator or confirm the absence of indicators.) Depth Matrix Redox Features (inches) Color (moist) % Color (moist) % Type1 Loc2 Texture Remarks 0-16 10YR 3/2 100 loam gravels; dry 16-20+ 10YR 3/3 100 loam gravels; dry 1Type: C= Concentration, D=Depletion, RM=Reduced Matrix, CS=Covered or Coated Sand Grains. 2Location: PL=Pore Lining, M=Matrix Hydric Soil Indicators: (Applicable to all LRRs, unless otherwise noted.) Indicators for Problematic Hydric Soils3: Histosol (A1) Sandy Redox (S5) 2 cm Muck (A10) Histic Epipedon (A2) Stripped Matrix (S6) Red Parent Material (TF2) Black Histic (A3) Loamy Mucky Mineral (F1) (except MLRA 1) Very Shallow Dark Surface (TF12) Hydrogen Sulfide (A4) Loamy Gleyed Matrix (F2) Other (Explain in Remarks) Depleted Below Dark Surface (A11) Depleted Matrix (F3) 3Indicators of hydrophytic vegetation and wetland hydrology must be present, unless disturbed or problematic. Thick Dark Surface (A12) Redox Dark Surface (F6) Sandy Mucky Mineral (S1) Depleted Dark Surface (F7) Sandy Gleyed Matrix (S4) Redox Depressions (F8) Restrictive Layer (if present): Hydric Soils Present? Yes No Type: Depth (inches): Remarks: No hydric soil indicators present. HYDROLOGY Wetland Hydrology Indicators: Primary Indicators (minimum of one required; check all that apply) Secondary Indicators (2 or more required) Surface Water (A1) Water-Stained Leaves (B9) Water-Stained Leaves (B9) High Water Table (A2) (except MLRA 1, 2, 4A, and 4B) (MLRA 1, 2, 4A, and 4B) Saturation (A3) Salt Crust (B11) Drainage Patterns (B10) Water Marks (B1) Aquatic Invertebrates (B13) Dry-Season Water Table (C2) Sediment Deposits (B2) Hydrogen Sulfide Odor (C1) Saturation Visible on Aerial Imagery (C9) Drift Deposits (B3) Oxidized Rhizospheres along Living Roots (C3) Geomorphic Position (D2) Algal Mat or Crust (B4) Presence of Reduced Iron (C4) Shallow Aquitard (D3) Iron Deposits (B5) Recent Iron Reduction in Tilled Soils (C6) FAC-Neutral Test (D5) Surface Soil Cracks (B6) Stunted or Stresses Plants (D1) (LRR A) Raised Ant Mounds (D6) (LRR A) Inundation Visible on Aerial Imagery (B7) Other (Explain in Remarks) Frost-Heave Hummocks (D7) Sparsely Vegetated Concave Surface (B8) Field Observations: Surface Water Present? Yes No Depth (inches): Wetland Hydrology Present? Yes No Water Table Present? Yes No Depth (inches): Saturation Present? (includes capillary fringe) Yes No Depth (inches): Describe Recorded Data (stream gauge, monitoring well, aerial photos, previous inspections), if available: Remarks: No indicators of wetland hydrology present. Area dry despite record rainfall for month of October 2016. Project Site: PSE - Talbot Hill Substation