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<br />Lexington-Broadway Stormwater Imp. Phase 1 7 Scope of Services <br />and the City would be responsible for payment for this work through a separate agreement <br />with HWA. <br />A. During drilling of the geotechnical borings, screen soils for organic vapors by headspace <br />analysis using a photoionization detector (PID), a water sheen test, and visual and <br />olfactory methods (i.e., stained, or discolored soils and/or adverse odors). If field <br />indications of contamination are detected, HWA will collect at least one soil sample from <br />each suspect contaminated boring location. <br />B. Groundwater samples would also be collected from suspect contaminated boring <br />locations via temporary or permanent wells installed during drilling activities. If HWA <br />intends to collect groundwater samples from any permanent wells, the drillers will <br />develop the wells following construction of the well. Soil and groundwater samples will <br />be collected following HWA and regulatory agency standard operating procedures. <br />C. If suspect contaminated soil and/or groundwater samples are collected, the samples <br />collected will be submitted to a Washington State Department of Ecology (Ecology)- <br />accredited, third-party analytical laboratory (Onsite Environmental of Redmond, <br />Washington). For each suspect boring, the soil samples with the highest level of organic <br />vapors and/or most discernible visual/olfactory contamination will be selected for <br />chemical analysis. Field staff will deliver samples to the analytical laboratory within 48 <br />hours of sampling. HWA will employ full chain-of-custody procedures to allow tracking <br />and handling of the samples. HWA will select one soil sample and one groundwater <br />sample (if encountered) per suspect boring (maximum of six soil samples and six <br />groundwater samples) for chemical laboratory analysis of the following: <br />i. Petroleum hydrocarbons–gasoline via Ecology test method NWTPH-Gx <br />ii. Petroleum hydrocarbons–diesel, oil via Ecology test method NWTPH-Dx <br />iii. Benzene, toluene, ethylbenzene, and xylenes (BTEX) via U.S. Environmental <br />Protection Agency (EPA) Test Method EPA 8260D <br />iv. Carcinogenic polycyclic aromatic hydrocarbons (cPAHs) via EPA Test Method EPA <br />8270E/SIM <br />v. Resource Conservation and Recovery Act (RCRA) 8 metals (Ag, As, Ba, Cd, Cr, Hg, <br />Pb, and Se) via EPA Test Method EPA 6010/7000 <br />vi. Toxicity Characteristic Leaching Procedure (TCLP) via EPA Test Method EPA <br />1211/6010D <br />D. Because of the limited information regarding historical uses and potential contaminants <br />of concern in the vicinity of the proposed stormwater treatment facility, chemical <br />laboratory analysis of the environmental soil and/or groundwater samples submitted is <br />based on general disposal facility requirements, which may vary based on the disposal <br />facility. Samples will be submitted for standard laboratory turnaround time, which is <br />approximately 7 to 10 business days. Follow-up analyses, based on initial analytical <br />results (i.e., TCLP follow-up analysis) may result in a total standard turnaround time of <br />up to 3 weeks.