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<br /> December 29, 2016 | Page 1 File No. 0504-119-00 <br />1.0 INTRODUCTION <br />This report describes soil and groundwater assessment activities conducted at the Kittitas County Lower <br />Shop site located at 505 West 14th Avenue in Ellensburg, Washington (herein referred to as “site”). The <br />approximate site location is shown in the attached Vicinity Map, Figure 1. <br />Site environmental activities are managed by the Washington State Department of Ecology (Ecology). This <br />report describes field activities, observations and chemical analytical results associated with soil and <br />groundwater samples collected at the site. The purpose of the assessment activities described herein was <br />to identify if remnant soil and groundwater contamination associated with former underground storage tank <br />(UST) operation was present beneath the site. Ecology will use the assessment results to conduct a Site <br />Hazard Assessment (SHA), if necessary, or close the site. <br />2.0 SITE DESCRIPTION AND BACKGROUND <br />The county shop is located in a residential area of Ellensburg, Washington. The approximate site location <br />is shown in the Vicinity Map, Figure 1. The site is bounded by 15th Avenue to the north, 14th Avenue to the <br />south, residential property to the west and Okanogan Street to the east. Four maintenance or shop buildings <br />and a yard are located on the unpaved site. <br />In May 1990, Kittitas County removed three USTs from the site just north of the office building. Evidence <br />of a petroleum release was not recorded during UST removal actions; however, analytical testing was not <br />performed. TerraGraphics completed a Phase II environmental site assessment in July 2013, and <br />encountered petroleum-impacted soil near the former UST basin in three borings. The approximate <br />locations of the former USTs and borings are shown in the Site Plan, Figure 2. The soil samples collected <br />at about 5 feet below ground surface (bgs) from the three 2013 borings exceeded the Model Toxics Control <br />Act (MTCA) Method A cleanup levels for gasoline-range petroleum hydrocarbons (GRPH), total xylenes, <br />ethylbenzene, and naphthalene. <br />3.0 SCOPE OF SERVICES <br />The scope of services included the following: <br />1. Prepared a Master Work Plan that included a Sampling and Analysis Plan (SAP), Quality Assurance <br />Project Plan (QAPP), and Health and Safety Plan (HASP). <br />2. Coordinated underground utility locating using the one-call system and Utilities Plus, a private utility <br />locator. Per state regulations, the proposed boring locations were marked prior to initiating the locate <br />request. <br />3. Coordinated subcontractors (drillers, locators and waste disposal contractors) and provided project <br />management services. <br />4. Conducted field assessment activities including the following: <br />a. Observing Environmental West Explorations, Inc. (Environmental West) drill seven soil <br />borings (B-1 through B-7) using direct-push drilling techniques. Temporary well screens