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MW •0,
<br /> West Clay Properties Page 2 of 2
<br /> 639 West Clay Street September 20, 2013
<br /> Stockton, California 95206
<br /> • Operation of the in-situ ozone sparge (IOS) remediation system for approximately twelve
<br /> to eighteen months;
<br /> • Evaluation of the IOS system during the first month of operation by weekly monitoring
<br /> the pressure delivered to each sparge point, and measuring dissolved oxygen (DO),
<br /> oxidation reduction potential (ORP), hydraulic effects, chemical reactions, and
<br /> contamination reduction at monitoring wells MW-1, MW-2, MW-29 and possibly
<br /> extraction well EW-2; groundwater collected during the four sampling events within the
<br /> first month of operating the IOS system will be analyzed for TPH-g, BTEX, MTBE, ETBE,
<br /> DIPE, TAME, TBA, volatile organic compounds (VOCs), total dissolved solids (TDS),
<br /> general minerals and California Assessment Manual (CAM) 17 metals listed in the work
<br /> plan, hexavalent chromium (Cr+6), chromium III, manganese, iron, dissolved iron,
<br /> bromide, bromate, chloride, phosphate, nitrate, nitrite, sulfate, total hardness, chemical
<br /> oxygen demand, and total organic carbon; thereafter, with the exception of Cr+6, VOCs,
<br /> TDS and general minerals, the above-listed parameters will be collected monthly for a
<br /> minimum period of six months;
<br /> • Termination of the remediation system if harmful byproducts are detected and reported
<br /> at elevated concentrations within the first month of operation of the IOS system; and
<br /> continuation of monitoring for harmful byproducts until concentrations return to near
<br /> background levels;
<br /> • Submittal of a remedial action report following the first month of operating the IOS
<br /> system; and submittal of quarterly reports thereafter.
<br /> The EHD approves the work plan as submitted. Submit a Well and Boring Permit Application,
<br /> Master File Record form, permit/inspection fees and complete the installation of the IOS system
<br /> by 31 December 2013. Notify the EHD of pending fieldwork at least two weeks prior to the
<br /> event.
<br /> If you have any questions concerning this letter, please contact Vicki McCartney at (209) 468-
<br /> 9852, or by email at vmccartney(c slcehd.com.
<br /> Sincerely,
<br /> Victoria L. McCartney, RELi HS Nuel C. Henderson, Jr., PG
<br /> Senior Registered Environmental Hea Specialist Engineering Geologist
<br /> c: Mr. William R. Little, PG, Advanced GeoEnvironmental, Inc., 837 Shaw Road,
<br /> Stockton, California 95215
<br /> Mr. James L.L. Barton, PG, California Regional Water Quality Control Board Central
<br /> Valley Region, 11020 Sun Center Drive, Suite 200, Rancho Cordova, California 95670
<br />
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