Laserfiche WebLink
Eoauno(G.Baown Jn. <br /> MC oitPfOgnalnJE: <br /> Water Boards <br /> Central Valley Regional Water Quality Control Board <br /> 23 May 2017 <br /> Satinder Singh Dilawri Aman Business Enterprise Inc. <br /> Vicinity Inc. 801 N. Granda Drive #14A <br /> 420 W. Yosemite Avenue Madera, CA 93637 <br /> Manteca, CA 95337 <br /> Harjit Songh Et AI Fassel &Amal Elder <br /> 1675 Paseo Laguna Seco 4880 Peach Avenue <br /> Livermore, CA 94550 Manteca, CA 95337 <br /> RAINWATER CAR WASH, 420 YOSEMITE AVENUE, MANTECA, SAN JOAQUIN <br /> COUNTY, CASE#390835 <br /> Central Valley Regional Water Quality Control Board (Central Valley Water Board) staff have <br /> reviewed the Site Assessment Report(Report) dated 15 March 2017, submitted on your <br /> behalf by Advanced GeoEnvironmental Inc. (AGE), for the Rainwater Car Wash (Rainwater) <br /> property at 420 West Yosemite Avenue in Manteca (Site). <br /> To define the lateral and vertical extent of downgradient petroleum hydrocarbon impact to <br /> groundwater, AGE advanced four(4) borings (P11, P12, P14, P15) to 115 feet below ground <br /> surface (bgs) in January 2017. AGE collected grab groundwater samples from each boring <br /> at approximately 30, 60, 90, and 115 feet bgs. <br /> Based on a combination of September 2016 monitoring well data and the January 2017 grab <br /> sampling, it appears that the extent of total petroleum hydrocarbons as gasoline (TPHg) and <br /> benzene are adequately defined. Additionally, the extent of methyl tert butyl ether (MTBE) <br /> appears to be defined to the south, east, and west. However, AGE detected MTBE in <br /> samples collected from borings P12 and P14, the furthest downgradient sampling points to <br /> date, at all sampled depths. AGE detected up to 120 ug/L at 60 feet bgs in boring P12 and <br /> up to 210 ug/L at 115 feet in boring P14. The maximum MTBE concentration of 1,800 <br /> micrograms per liter (ug/L) was reported in P15 at 65 feet bgs. As such, the downgradient <br /> extent of MTBE remains undefined. <br /> Central Valley Water Board staff have the following comments on the status of the <br /> assessment and cleanup of the petroleum release from the Site: <br /> 1. In the Report, AGE recommends submitting a Work Plan to advance two (2) additional <br /> deep borings: one approximately 270 feet northwest of P12 and one approximately 270 <br /> feet north of P14. As the extent of MTBE remains undefined, Central Valley Water Board <br /> staff concur with this recommendation. <br /> i <br /> KFRL E. LONGLEY SCD, P.E.. CHAIR I PAMELA C. CREEOON P.E., BCEE, EXECUTIVE OFFICER <br /> 111120 Sun Conter Crivc p200,RancM10 COfUOVR.CA 05610 � www.waterboartls.ca.gov/cent191vallay j <br /> <i P¢crcEo vnr[n <br />