7301 EVERGREEN WAY EVERETT CHEVROLET 2017-03-01

2.0 SITE IDENTIFICATION AND DESCRIPTION 2.1 Site Description The Site is located at 7300 Evergreen Way and consists of an approximate 4-acre irregularly-shaped piece of land located in a mixed commercial and residential area of Everett, Snohomish County, Washington. The Site appears to consist of two parcel numbers (208507-002-038-00 and 003939-001-005-01), recorded with Snohomish County with the address "7301 Evergreen Way". The Site Location is presented on Figure 1. Improvements to the Site include a 19,200 square-foot main building (Building 1), a 16,600 square-foot storage/parts warehouse (Building 2), a 385 square-foot used car sales building (Building 3), and asphalt paved exterior surfaces. A Site Plan is presented on Figure 2. The Site is currently inactive, but was recently utilized by Everett Chevrolet as a new and used car showroom and automobile service department. Supporting operations included vehicle washing and servicing, and sales and administrative activities. The MTCA site is defined as all current and historical affected areas from the petroleum release associated with the Site. The MTCA site boundary is presented on Figure 2. The MTCA site is contained within the Site boundary and does not extend to any adjacent parcels. 2.2 Site Background Total Petroleum Hydrocarbons (TPH) in the motor oil range (TPHo) were released into soil within the vicinity of several former in-ground hydraulic lifts (six in Building 1 and two in Building 2) sometime prior to 1994. A total of eight groundwater monitoring wells (MW-1 through MW-8), 57 soil borings, and 24 confirmatory soil samples have been completed at the Site to date. A total of nine environmental investigations related to this release were completed at the Site and summarized as part of the RI/FS report. All in-ground hydraulic lifts have either been removed, or drained and permanently decommissioned, and the majority of the impacted soil associated with the in-ground hydraulic lifts was excavated in 1999 (approximately 458 tons). Some impacted soil was left in-place at that time because of the proximity to building foundations and structures. A summary of the soil analytical data compared to the MTCA Method A Cleanup Levels for protection of groundwater as a drinking water resource and MTCA Method A Direct Contact Cleanup levels for protection of human health are presented in Table 1. The extent of petroleum hydrocarbon-impacted soil has been defined at the Site in comparison to MTCA Method A screening levels. Isoconcentration contours indicating TPHo concentrations exceeding the MTCA Method A Cleanup Level for protection of groundwater (2,000 milligrams per kilogram [mg/kg]) is presented on Figures 3 and 4. Residual TPHo impacts exceeding the MTCA Method A screening levels are present in soil beneath the northwest portion of Building 1 within the Quick Lube Service Bays, in the southeast portion of Building 1 within the Shop Service Bays, and in the southern portion of Building 2 within the Parts Warehouse. Residual TPHo soil impacts are limited to areas beneath existing buildings, beneath concrete slab, in small isolated areas surrounding the footing of the former in-ground hydraulic lifts. All residual soil impacts are associated with former in-ground hydraulic lifts; all in-ground lifts which were previously present at the Site have been removed or drained and permanently decommissioned. Groundwater at the Site was encountered at depths ranging from 1.61 feet (ft) below ground surface (bgs) to 18.47 ft bgs during monitoring well sampling conducted by IT in August 1999 and EEC in 2011. Impacted soil has been identified between 5 and 14 ft bgs; therefore all soil impacts have been in 017386-174(123) 2 THIS DOCUMENT IS PRINTED ON RECYCLED PAPER Encore Environmental Consortium,LLC