SITE INFORMATION AND CORRESPONDENCE

Home Browse Search

RECER&D :.fir. EuMuxu G.opwBPuwx Jrv. a, - wFnnoP a A\L.eaaLA FEB 0 6 2014 .. P M` Water Boards ONM 6NViPOHM6NihL PPniECi,Ox ENVIRONMENTAL HEALTH Central Valley Regional Water Quality Control Board 5 February 2014 George Betker 2306 Jackie Court Oakdale, CA 95361 NOTICE OF INTENT, FORMER JM EQUIPMENT, 1245 WEST CHARTER WAY, STOCKTON, SAN JOAQUIN COUNTY On 14 January 2014, Ground Zero Analysis, Inc. (GZA) submitted a Notice of Intent (NOI) and supporting technical information (work plans and reports) to operate under Waste Discharge Requirements of General Order R5-2008-0149 (General Order) on your behalf for your site at 1245 West Charter Way in Stockton. The Not describes the proposed injection of hydrogen peroxide into groundwater from an injection system consisting of seven injection wells screened from 15 feet below ground surface ('bgs) to 25' bgs. The injection system has been designed to oxidize petroleum hydrocarbon contaminants, including methyl tertiary butyl ether (MTBE), in groundwater found between 11- 17 feet below ground surface. The Former JM Equipment conducted a pilot study in 2011 and 2012 using hydrogen peroxide injections showing this cleanup technology was successful at reducing concentrations of petroleum hydrocarbons in groundwater at this Site. Central Valley Water Board staff requested on 22 January 2014 that the NOI be modified to include a revised Contingency Plan to conduct active remediation to address potential adverse impacts caused by the injections, if detected. On 28 January 2014, GZA submitted a revised NOI by email. Excerpts from the revised NOI are italicized in the following paragraphs and our comments to the revisions follow. 1. "Hexavalent chromium concentrations in treatment zone observation wells OW-1, OW-2, OW-3, MW- 5 and MW-9 were reported to range from 0.072 Ng/L (OW-2) to 15 Ng/L (OW-3). Well OW-2 received hydrogen peroxide infection, while well OW-3 was used as a control well and did not receive any remediation during the Phase l pilot test." The pilot study results submitted in the 29 June 2012 monitoring report indicate IW-2 received the injections and OW-2 was the paired observation well. Injecting an oxidant into an observation well is, not allowed since the pilot study results would be skewed to show that the oxidant decreased concentrations only in the observation well, which may not translate to the surrounding aquifer. Did you mean OW-2 was used to observe the IW-2 injections? If so, please provide correction or clarification in a revised NOI. 2. "in summary, GZA recommends that the background hexavalent chromium concentration for the Site be set at 15 Ng/L." KARL E. LONCLEY SCD, P.E., CHAIR I PAMELA C. CREEDON P.E., BCEE, CMEOOTIVE OrrID[R 11020 Sun Center Drive#200,Rancho Cordova,CA 86870 1 www.waterboards.ca.gov/centralvalley L+P[GYGLPC PMEP