The City of South Tucson conducted a Phase II Environmental Site Assessment ESA at the City of South Tucson Public Works Yard, an operating municipal vehicle maintenance and storage facility, located at 1601 S. 5th Avenue in South Tucson, Arizona. The purpose of the Phase II ESA was to further investigate the following recognized environmental condition REC at the site as documented in a Phase I Environmental Site Assessment dated February 17, 2007: � There are no standard records associated with the two reported underground storage tanks USTs at the facility that have been decommissioned and that are no longer being used. These USTs should be removed and soil and/or groundwater should be investigated in accordance with applicable local, state, and federal rules and regulations. The two USTs consist of one 2,500-gallon capacity UST formerly used to store diesel fuel and one 4,500-gallon capacity UST formerly used to store gasoline fuel. In order to adequately assess whether leaks or spills from the UST system potentially impacted site soil, the USTs were removed. A subcontractor removed concrete overlying the USTs, excavatd soil overlying the USTs and associated piping, and removed the USTs and associated product piping from March 4, 2010 through March 9, 2010. Site sampling activities were conducted by Allwyn Environmental on March 9, 2010. The following samples were collected: � Nine samples from soil beneath the diesel fuel UST, dispenser, and product piping and fittings � Seven samples from soil beneath the gasoline fuel UST, dispenser, and product piping, and fittings � Three samples from the excavated soil stockpile Samples collected from the diesel fuel UST system were analyzed for total petroleum hydrocarbons TPH using EPA Method 8015AZ and polynuclear aromatic hydrocarbons PAHs using EPA Method 8310. Samples collected from the gasoline fuel system were analyzed for TPH using EPA Method 8015AZ and benzene, toluene, ethylbenzene, and xylenes BTEX using EPA Method 8260B. Samples collected from the soil stockpile were analyzed for BTEX, TPH, and PAHs. Naphthalene was present in soil at a concentration above the applicable analytical laboratory method detection limits MDLs of 0.020 milligrams per kilogram mg/kg in one sample collected from the diesel fuel system TK1-3. Ethylbenzene and total xylenes were present in soil at concentrations above the applicable analytical laboratory MDLs of 0.050 mg/kg and 0.15 mg/kg, respectively, in one sample collected from the gasoline fuel system TK2-4. Naphthalene, ethylbenzene, xylenes, and C10 � C22 hydrocarbons were present in soil at concentrations above the applicable analytical laboratory MDLs of 0.020 mg/kg, 0.050 mg/kg, 0.15 mg/kg, and 30 mg/kg, respectively, in one soil stockpile sample SS2. No other PAH, TPH, or BTEX analyte was present in this sample above the MDL in any other samples. No constituents were present in soil at concentrations above the applicable State of Arizona non-residential or residential Soil Remediation Levels SRLs. Based on the results of the Phase II ESA and the results and conclusions in the Phase I ESA, the portion of the site associated with the diesel fuel and gasoline fuel UST systems have been adequately characterized and no further assessment is recommended for these portions of the site.
Former Use: The subject property has been either vacant and undeveloped since sometime between 1988 and 1994 aerial photograph review and property owner interview, after which time it has been used for the City of South Tucson�s Public Works administration, maintenance, and storage.