MEMORANDUM. Mike Merryfield, Art Brass Plating, Inc. Jeremy Porter, P.E. and Doug Hillman, LHG

Transcription

1 December 1, 2005 MEMORANDUM Project No.: To: cc: From: Re: Mike Merryfield, Art Brass Plating, Inc. Bill Joyce, alter Joyce Ziker Jeremy Porter, P.E. and Doug Hillman, LHG Follow-up ite Investigation Results Art Brass Plating, Inc Third Avenue outh, eattle, Washington This memorandum presents the results of our follow-up subsurface investigation conducted at the Art Brass Plating, Inc. (Art Brass) facility located at 5516 Third Avenue outh and in the surrounding Georgetown neighborhood in eattle, Washington. The site location is shown on Figure 1. The location of the site in the surrounding neighborhood is shown on Figure 2 with the exploration locations. In a preliminary soil and groundwater investigation conducted in June 2005, we identified trichloroethene (TCE) and related constituents in soil, soil gas, and groundwater beneath the Art Brass facility and in areas of former degreasing operations. pecific goals of this followup work were as follows: Confirm the groundwater concentrations detected in the preliminary investigation and estimate local groundwater flow direction by installing four monitoring wells on the Art Brass Plating property; Evaluate the vertical extent of chemical occurrences; and Conduct neighborhood-area groundwater sampling to evaluate the horizontal extent of chemical occurrences downgradient of the facility. The first objective was accomplished by installing four monitoring wells on the Art Brass property downgradient of the degreasing operations. The second and third objectives were achieved by soil probe borings advanced in the neighborhood area. Results of this investigation indicate that the contamination is confined to the shallow groundwater near the water table and immediately downgradient of the facility. A discussion of the results and an updated site conceptual model are provided below. Field Investigation Field investigations consisted of hollow-stem auger drilling for monitoring well installation and probe drilling to further assess horizontal and vertical extent of TCE distribution. Monitoring wells were installed downgradient of the former degreaser located towards the central portion of the shop and the vapor degreaser located in the western section of the shop. 811 First Avenue, uite 480 eattle, WA Tel: (206) Fax: (206)

2 MEMORANDUM December 1, 2005 Project No Two additional wells were installed downgradient of the degreaser just beyond the footprint of the Art Brass building. oil probes were advanced in the neighborhood area along Findlay treet and 2 nd and 3 rd Avenues outh. Monitoring Wells On October 5, 2005, Aspect Consulting installed four monitoring wells using a limited-access hollow stem auger rig operated by Holt Drilling of Puyallup, Washington. Wells were installed to an approximate depth of 14 feet and screened from 4 to 14 feet in depth (across the water table). Well installation logs are provided in Attachment A. Well MW-1 is located less than 10 feet downgradient of the current degreaser and well MW-3 is approximately 30 feet further downgradient. Well MW-2 is located about 10 feet downgradient of the former degreaser and well MW-4 is 50 feet further downgradient. Well locations are illustrated on Figure 2. Wells MW-1, MW-3, and MW-4 are located adjacent to previous soil borings therefore no soil samples were collected during well installation. The location of MW-2 was not associated with a previous boring therefore soil samples were collected at 2.5-foot intervals to characterize subsurface conditions. oils were logged, and screened with a photoionization detector (PID) for the presence of volatile organic chemicals (VOCs). Three soil samples from MW-2 were selected for chemical analysis for VOCs on the basis of field observations and PID readings. oil samples were collected by EPA Method 5035A and field-preserved in methanol and submitted to Advanced Analytical Laboratory (AAL) for analysis of VOCs by EPA Method 8260B. Monitoring wells were developed on October 6, 2005 and were sampled on October 18, 2005 using low-flow techniques. Field parameters monitored include ph, temperature, dissolved oxygen, conductivity, and redox potential. Four groundwater samples were submitted to AAL for analysis of VOCs by EPA Method 8260B. The top-of-casing elevations of each well were surveyed in to estimate the direction of groundwater flow at the site. Top-ofcasing elevations were tied into nearby PC water table wells, 138-WT and 136-WT. Water levels were measured at the Art Brass wells and the PC wells on October 7, Neighborhood Area Groundwater Assessment After the local groundwater flow direction was estimated from monitoring well data, we advanced nine soil borings along public right-of-ways downgradient of the facility. Borings were advanced on October 11, 2005 using a direct-push rig operated by Geo-Tech Explorations of Portland, Oregon. Boring locations are shown on Figure 2. The probe sampling effort consisted of: Groundwater samples collected from each boring at the identified top of the water table (approximately 7 to 8 feet deep). Two deeper borings (PO-2 and PO-3) located downgradient of borings P-1 and P-3, respectively. oil samples were collected at continuous intervals, logged, and screened with a PID for the presence of VOCs. ample intervals for potential analysis were selected on the basis of PID readings, the location of groundwater and the presence of Page 2

3 MEMORANDUM December 1, 2005 Project No contacts between coarse- and fine-grained materials. Groundwater and corresponding soil samples were collected above low-permeability layers, if present, and at a minimum frequency of every 15 feet in depth below the water table. The borings were advanced to a depth of 42 and 45 feet, for PO-2 and PO-3, respectively. ix soil samples were submitted to AAL for analysis of VOCs by EPA Method 8260B. oil samples from borings PO-2 and PO-3 were collected for chemical analysis using EPA Method 5035A techniques. oil boring logs are provided in Attachment A. Groundwater samples were collected from each boring using a temporary 4-foot-long screen placed near the top of the water table (as observed at time of drilling). Additional deeper groundwater samples were collected from boring PO-2 at depths of 22 to 26 feet and 39 to 42 feet and from boring PO-3 at depths of 23 to 27 feet and 41 to 45 feet. Groundwater samples were collected by purging with a peristaltic pump to reduce turbidity and sampling using low-flow sampling techniques. Thirteen groundwater samples were submitted to AAL for analysis of VOCs by EPA Method 8260B and total suspended solids by EPA Method ite Geology and Hydrogeology Most of the Art Brass site is covered by the concrete building foundation slab, approximately 6 inches thick. The parking area in the south-central portion of the site and the storage area in the northwest corner are paved with asphalt. Neighborhood roads are paved with asphalt; however, the parking strips on either side of the right-of-ways are often soil and gravel. oils in the neighborhood area generally consist of an upper layer of sand or gravelly sand, typically 1 to 4 feet thick, that is underlain by varying layers of sand, silty sand and sandy silt to approximately 8 to 11 feet in depth. Below 8 to 11 feet in depth, soils consisted of fine-tomedium sands with occasional silt interbeds. As indicated by two borings, the lithology changes back to a silty sand and sandy silt at a depth of 22 to 23 feet. A generalized geologic cross section for the site is provided on Figure 3. Groundwater was encountered at depths between 6.5 and 8 feet at borings located in the vicinity of the Art Brass facility. The depth to water at boring PO-9 was 11 feet; however, it is located approximately 400 feet downgradient of the Art Brass facility. Heaving sands have generally been encountered at depths below 12 feet. The estimated flow direction of shallow groundwater in the area is to the west-southwest, as shown on Figure 4. This flow direction is estimated using the on-site monitoring wells in addition to PC water table wells 138-WT and 136-WT. Analytical Results Analytical results for chemicals detected at the site are summarized in Table 1 for soil, Table 2 for groundwater samples collected from soil probes, and Table 3 for groundwater samples collected from monitoring wells. Occurrences are compared to MTCA Method A (when available) and Method B cleanup levels for unrestricted use of groundwater for preliminary screening purposes only. Inhalation Pathway Interim Measure Action Levels (IPIMALs) Page 3

4 MEMORANDUM December 1, 2005 Project No established for the PC Georgetown cleanup are provided for comparison purposes only (PTC 2003). Laboratory certificates of analysis are provided in Attachment B. Detected occurrences are discussed below. oil Results Non-Chlorinated VOCs. Non-chlorinated VOCs were not detected in soil. Chlorinated VOCs. Only two chlorinated VOCs TCE and cis-1,2-dichloroethene (cis- DCE) were detected in soil. oils collected for analysis were located adjacent to the former degreaser (MW-2) and downgradient of both degreasers within the Findlay treet right-ofway (PO-2 and PO-3). Detected occurrences of both these analytes correlated spatially with their occurrence in groundwater. Detected concentrations ranged as follows: TCE was detected in soil both above and below the water table in boring MW-2 with concentrations ranging from 32 to 1,600 ug/kg, with the higher concentration at the water table. Downgradient of the facility at borings PO-2 and PO-3, concentrations ranged from 640 to 94 ug/kg for the soils near the water table. TCE was not detected in soil below 20 feet. cis-dce was detected in soil at boring MW-2 near the water table 100 ug/kg. Downgradient of the facility, cis-dce was detected near the water table at one location (PO-2), at 76 ug/kg. Groundwater Results Non-Chlorinated VOCs. Non-chlorinated VOCs were not detected in groundwater. Chlorinated VOCs. Eight chlorinated VOCs were detected in groundwater at the site. Three of these chloroethane, 1,1-dichloroethane, 1,2-dichloroethane were detected in the samples collected from borings PO-2 and PO-3 at concentrations well below the MTCA Method B cleanup levels. Chlorinated ethanes have not been detected at the Art Brass site but have been detected at low levels in the greater Georgetown neighborhood. The other five detected chlorinated VOCs consist of TCE and biodegradation products of TCE: cis-dce, trans-1,2-dichloroethene (trans-dce), 1,1-dichloroethene (1,1-DCE), and vinyl chloride. Occurrences of chlorinated ethenes in groundwater at the water table and in deeper groundwater are described below: hallow Groundwater TCE concentrations in groundwater at the water table ranged from 1,000 to 4,200 ug/l in borings and monitoring wells located within 80 feet downgradient of the facility (PO-2, PO-3, PO-6, PO-7, MW-3, and MW-4). TCE concentrations detected greater than 80 feet downgradient of the facility ranged from 230 ug/l to non-detect. As noted in the previous investigation, the highest concentrations were detected close to and in the downgradient direction of the vapor degreaser locations. Occurrences of TCE in shallow groundwater are shown on Figure 4 relative to occurrences detected in the vicinity during the PC off-site investigations. Page 4

5 MEMORANDUM December 1, 2005 Project No cis-dce concentrations in groundwater generally correlated with the detected TCE concentrations. Concentrations immediately downgradient of the property boundary ranged from 59 to 1,100 ug/l, and concentrations 80 feet further downgradient ranged from non-detect to 80 ug/l (at PO-4). Concentrations from monitoring wells MW-1 and MW-2 on the property were 650 and 31 ug/l, respectively. trans-dce concentrations in groundwater were much lower than cis-dce concentrations, ranging from non-detect to 9.7 ug/l. 1,1-DCE was generally not detected except at two locations (PO-2 and PO-6) at a maximum concentration of 1.5 ug/l. Vinyl chloride was detected at three soil probe borings (PO-2, PO-3, and PO-6) and two monitoring wells (MW-3 and MW-4) at concentrations between 0.23 and 1.4 ug/l. Previous groundwater investigations in the area conducted by PC detected vinyl chloride beneath 4 th Avenue outh, in the upgradient direction from the site, at concentrations up to 12 ug/l (boring M13). Deep Groundwater In the two deep borings, PO-2 and PO-3, a total of four groundwater samples were collected below the water table, two samples collected between 22 and 27 feet deep and two from 39 to 45 feet deep. The screen interval from the 22 to 27 foot was placed above geologic contact were the lithology changed from a sand to a sandy silt to silty sand. ince no geologic contact was observed below this point, the deeper screened intervals from 39 to 45 feet were set about 15 feet below the previous interval. Detected concentrations at these two intervals ranged as follows: 22 to 27 feet deep: Concentrations of TCE and cis-dce from this interval were less than the concentrations detected at the water table in the same borings. TCE was only detected in boring PO-3 at a concentration of 6.1 ug/l. Biodegradation products cis- DCE, 1,1-DCE and vinyl chloride were detected in boring PO-2 at concentrations of 42, 1.6, and 50 ug/l, respectively. Vinyl chloride and 1,1-DCE were detected in PO-3 at concentrations of 18 and 4.2 ug/l, respectively. 39 to 45 feet deep: No VOCs were detected in the groundwater samples collected below 39 feet. Updated Conceptual ite Model Based on the data collected to date in the Georgetown neighborhood, we have a reasonable understanding of the extent of contamination in the surrounding neighborhood of the Art Brass facility. PC has conducted several investigations in the Georgetown area as part of their off-site characterization and IPIM program. Aspect Consulting has now completed two investigation programs in June and October 2005 at the Art Brass facility and in the surrounding area. Investigations in the vicinity of Art Brass indicate that low-level concentrations of VOCs are present in groundwater in the Georgetown area. Data collected along the upgradient property Page 5

6 MEMORANDUM December 1, 2005 Project No boundary both by Aspect Consulting and PC suggest that off-site sources located upgradient of Art Brass (e.g., PC, the former cleaners on 4 th Avenue outh, or former manufacturing facilities) may have resulted in low concentrations of TCE, cis-dce, and vinyl chloride in site soil and groundwater. TCE has been detected at the Art Brass facility in groundwater, soil, and soil vapor. Higher concentrations of TCE and cis-dce have been detected on site near areas where TCE was historically used for degreasing, suggesting that a historical release of TCE likely occurred at the facility. Groundwater samples collected from neighborhood area soil borings indicate the horizontal extent of contamination is limited to about a half-block radius from the intersection of outh Findlay treet and 3 rd Avenue outh. Deeper borings located downgradient of Art Brass indicate that the vertical extent of contamination is limited as groundwater samples from about 40 feet deep were non-detect for VOCs. Furthermore groundwater concentrations of TCE and associated biodegradation products below the water table zone are within the same order of magnitude as concentrations reported for the greater Georgetown plume as delineated by PC (PC 2004). These results suggest that impacts to groundwater at the Art Brass facility are generally confined to shallow groundwater near the water table. Upcoming Investigation Work The next planned step is to prepare a preliminary analysis of remedial alternatives to address TCE occurrences at the Art Brass facility. In this analysis we will also identify data needs for selecting and implementing an on-site remedial action. Because TCE concentrations in groundwater upgradient of facilities located at 215, 220, and 313 outh Findlay treet exceed IPIMALs set by Ecology for the PC Georgetown site, we are currently evaluating the potential for subsurface vapors from the groundwater plume to impact these facilities, and the potential need to apply interim mitigation actions. Page 6

7 MEMORANDUM December 1, 2005 Project No References Pioneer Technologies Corp., IPIM Technical Memorandum 4: Tier I and Tier 2 Evaluations of 1 st Quarter 2003 Groundwater Data, Phillips ervices Corporation, Georgetown Facility, eattle, Washington. Prepared far Phillips ervices. Dated June PC, Addendum III to the Final Comprehensive Remedial Investigation Report: Revised ection 9, Phillips ervices Corporation, Georgetown Facility, eattle, Washington. Prepared in coordination with Geomatrix. Dated eptember 24, Attachments: Table 1 Analytical Results for oil amples Table 2 Analytical Results for Groundwater amples from Direct-Push Borings Table 3 Analytical Results for Groundwater from Monitoring Wells Figure 1 ite Vicinity Map Figure 2 Neighborhood ite Plan with Exploration Locations Figure 3 Generalized Geologic Cross ection A-A with TCE Concentrations in Groundwater Figure 4 Occurrence of TCE in Groundwater Attachment A Boring Logs and Well Construction Details Attachment B Laboratory Data Quality Evaluation and Laboratory Certificates of Analysis Advanced Analytical Laboratory V:\ Art Brass Plating\Followup Investigation Data Memo.doc Page 7

8 Table 1 - Analytical Results for oil amples Location MW-2 PO-2 PO-3 Cuttings ample Number Comp1 MTCA Depth to Water (ATD) in Feet creening ample Depth in Feet 2.5 to to 9 15 to to to to to to to 45 Level ample Date 10/5/ /5/ /5/ /11/ /11/ /11/ /11/ /11/ /11/ /11/2005 (ee Note 1) VOCs by EPA Method 8260B (Detected Constituents Only) Chlorinated VOCs in ug/kg cis-1,2-dichloroethene 50 U J U 50 U 50 U 50 U 50 U 50 U 400 Trichloroethene 32 1, U 20 U U 20 U Notes: (1) MTCA Method A for unrestricted use (when available) and Method B cleanup levels for protection of groundwater supplied for preliminary screening purposes only. bold indicates analyte detected above screening level U = not detected at indicated detection limit V:\ Art Brass Plating\Followup Investigation Data Tables.xls - Table 1 soil

9 Table 2 - Analytical Results for Groundwater amples from Direct-Push Borings Location PO-1 PO-2 1 PO-2 2 PO-2 3 PO-3 1 PO-3 2 PO-3 3 PO-4 PO-5 PO-6 PO-7 PO-8 PO-9 MTCA Groundwater Groundwater Depth to Water (ATD) in Feet creening IPIMAL 2 IPIMAL 2 Depth of creen in Feet 7 to 11 7 to to to 42 7 to to to 45 8 to 12 8 to 12 7 to 11 7 to 11 7 to to 15 Level (Commercial) (Residential) ample Date 10/11/ /11/ /11/ /11/ /11/ /11/ /11/ /11/ /11/ /11/ /11/ /11/ /11/2005 (ee Note 1) VOCs by EPA Method 8260B (Detected Constituents Only) Chlorinated VOCs in ug/l Vinyl Chloride 0.2 U U U 0.2 U 0.2 U U 0.2 U 0.2 U Chloroethane 0.5 U 0.5 U U 0.5 U 1 U 1 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U ,1-Dichloroethene 0.5 U U 0.5 U 1 U 1 U 0.5 U 0.5 U U 0.5 U 0.5 U trans-1,2-dichloroethene 0.5 U U 1 U U 1 U 0.5 U 0.5 U U 0.5 U ,1-Dichloroethane 0.5 U 0.5 U 29 1 U U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U cis-1,2-dichloroethene 0.5 U U U U U ,2-Dichloroethane 0.5 U 0.5 U U 0.5 U 1 U 1 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U 0.5 U Trichloroethene ,800 1 U 1 U 1, U U 1,400 1, U Conventional Parameters T in mg/l ,000 1, Field Parameters Temperature in C pecific Conductivity in μ/cm ph Dissolved Oxygen in mg/l ORP Notes: (1) MTCA Method A (when available) and Method B cleanup levels for unrestricted use of groundwater supplied for preliminary screening purposes only. (2) IPIMALs are inhalation pathway interim measure action level established for the PC Georgetown cleanup. These are provided for comparison purposes only. bold indicates analyte detected above creening Levels as defined in Note 1. U = not detected at indicated detection limit -- indicates parameter not measured V:\ Art Brass Plating\Followup Investigation Data Tables.xls - Table 2 Probe_GWData

10 Table 3 - Analytical Results for Groundwater from Monitoring Wells MTCA Location MW-1 MW-2 MW-3 MW-4 creening Groundwater Depth of creen in Feet 3.75 to to 14 4 to 14 4 to 14 Level IPIMAL 2 ample Date 10/18/ /18/ /18/ /18/2005 (ee Note 1) (Commercial) VOCs by EPA Method 8260B (Detected Constituents Only) Chlorinated VOCs in ug/l Vinyl Chloride 0.2 U 0.2 U ,1-Dichloroethene 1.0 U 1.0 U trans-1,2-dichloroethene 1.0 U 1.0 U ,1-Dichloroethane 1.0 U 1.0 U U cis-1,2-dichloroethene 1, , Trichloroethene 2, ,200 3, Field Measurements Depth to Water in Feet TOC Elevation in Feet Groundwater Elevation in Feet Temperature in C pecific Conductivity in μ/cm ph Dissolved Oxygen in mg/l ORP Notes: (1) MTCA Method A (when available) and Method B cleanup levels for unrestricted use of groundwater supplied for preliminary screening purposes only. (2) IPIMALs are inhalation pathway interim measure action level established for the PC Georgetown cleanup. These are provided for comparison purposes only. (3) Monitoring well elevation based on NAVD88. bold indicates analyte detected above creening Levels defined in Note 1. U = not detected at indicated detection limit V:\ Art Brass Plating\Followup Investigation Data Tables.xls - Table 3 MW_GWData

11 N Feet ite Vicinity Map DATE: July 2005 DEIGNED BY: JJP 179 Madrone Lane North Bainbridge Island, WA (206) First Avenue #480 eattle, WA (206) Art Brass Plating eattle, Washington DRAWN BY: JR REVIED BY: PROJECT NO FIGURE NO. 1 Q:\Art Brass Plating\ Initial Report\ dwg ite Location

12 . LUCILE T Legend Approximate Property Boundary Catch Basin P15 ewer Line (Combined) O19 P17 PO nd Ave. Western Duplicating 200. Orcas treet Office Building 225. Lucile treet Dresser-Rand ALLEY 214F-GW Findlay treet Office Building PO-5 PO-4 PO-3 ALLEY 222. Orcas treet Quality Press 217. Findlay treet Warehouse 226. Orcas treet PO-7 PO-6 (D) Warehouse 217F 3RD AVE P Lucile treet N15 L18 P-12 MW-1 (P-9) P Orcas treet MW-4 (P-1) 307. Lucile treet P-6 ALLEY 313. Findlay treet Warehouse ALLEY P Orcas treet Warehouse P-5 P-8. FINDLAY T PO Lucile treet th Ave Orcas treet P-4 P rd Ave.. Art Brass Plating P-7 Parking 318. Orcas treet Office Building A A' 220-GW1 Note: ewer lines on. Lucile treet and west of 3rd Avenue not shown. MW-3 Proposed by PC PO-8 PO-2 (D) MW-2 Current Degreaser Former Degreaser 179 Madrone Lane North Bainbridge Island, WA (206) First Avenue #480 eattle, WA (206) th Ave. Restaurant th Ave. Auto Body hop ubway th Ave th Ave th Ave th Avenue treet Marco Polo Tavern 4TH AVE L14 M13 Neighborhood ite Plan with Exploration Locations Art Brass Plating eattle, Washington A N15 P-3 Vapor Degreaser Location Corrugated Metal Pipe (ewer Retention) oil Boring Location -Approximate (PC Off-ite Investiogations ) oil Boring (Aspect 2005) D = Deep ample MW-1 Monitoring Well (Aspect 2005) A' Note: Monitoring wells MW-1 and MW-4 were installed at the locations at P-9 and P-1, respectively. Cross ection DATE: November 2005 DEIGNED BY: DRAWN BY: REVIED BY: N Feet DLC JR PROJECT NO FIGURE NO. 2 Q:\Art Brass Plating\ Art Brass\ Exploration\ dwg

13 A House Warehouse Warehouse Art Brass Building A' PO-9 (8' E) PO-4 (35' NW) PO-3 (7' E) PO-6 (41' NW) PO-2 (46' E) MW-3 (26' NW) MW-1 (30' NW) MW-4 (38' E) MW-2 (8' NW) P-11 (12' NW) P-5 (40' NW) P-13 (25' E) P-4 (5' NW) M13 (57' NW) 20 ilty AND to andy ILT? 230 Gravelly AND 1,000 1,400 1,800 Gravelly AND 4,200 2,800 3, ilty AND to andy ILT 40 <1 <1?? <0.5 0 Fine to Medium AND Fine to Medium AND? 6.1 <1? <1-10 ilty AND to andy ILT -20 Legend Approximate Groundwater Elevation During 10/11/05 Drilling Based on ATD Permanent Well creen Interval with Groundwater ample Result Temporary creen Interval with Grab Groundwater ample Result Note: TCE concentration in µg/l. Bold values indicate sample collected from permanent monitoring well. Red indicates analyte detected above MTCA screening level. Green indicates analyte detected below MTCA screening level. <1 < Vertical Feet Horizontal Feet 179 Madrone Lane North Bainbridge Island, WA (206) First Avenue #480 eattle, WA (206) Generalized Geologic Cross ection A-A' with TCE Concentrations in Groundwater Art Brass Plating eattle, Washington DATE: DEIGNED BY: DRAWN BY: REVIED BY: November 2005 DLC JR PROJECT NO FIGURE NO. 3 Q:\Art Brass Plating\ Art Brass\ Exploration\ dwg

14 . LUCILE T Legend Approximate Property Boundary 8.5 Catch Basin P15 <1 M ewer Line (Combined) Vapor Degreaser Location Corrugated Metal Pipe (ewer Retention) N15 P-3 oil Boring Location -Approximate (PC Off-ite Investiogations ) oil Boring (Aspect 2005) D = Deep ample P ALLEY 1,200 PO PO-6 214F-GW1 1,400 <0.05 < PO-5 PO-4 1,000 PO-3 (D) 3RD AVE 4,200 MW-3 P-3 2,800 MW-1 (P-9) 2,800 (1,400) P-2 66 P MW-4 (P-1) PO-2 (D) 1, P-6 P-5 ALLEY MW-2 53 Current Degreaser 3,900 (5,700) 320 P-11 P Former Degreaser. FINDLAY T 0.93 PO-1 <1 P-4 <1 P-13 P-7 <1 4TH AVE <1 L14 MW-1 Monitoring Well (Aspect 2005) 2,800 Concentration in µ/l. Red indicates analyte detected above MTCA screening level. Green indicates analyte detected below MTCA screening level. Note: Monitoring wells MW-1 and MW-4 were installed at the locations at P-9 and P-1, respectively. 8.0 Groundwater Elevation Contour (Aspect, October 7, 2005) Note: Only data from water table aquifer are included. 217F 1,590 N15 46 ALLEY PO-9 <0.5 O19 < GW1 <0.05 Note: ewer lines on. Lucile treet and west of 3rd Avenue not shown. Proposed by PC PO L18 <0.05 ALLEY 179 Madrone Lane North Bainbridge Island, WA (206) First Avenue #480 eattle, WA (206) Occurrence of TCE in Groundwater Art Brass Plating eattle, Washington DATE: November 2005 DEIGNED BY: DRAWN BY: REVIED BY: N Feet DLC JR PROJECT NO FIGURE NO. 4 Q:\Art Brass Plating\ Art Brass\ Exploration\ dwg

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