SITE INFORMATION AND CORRESPONDENCE

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Treadwell&RDID Ms. Amy Terrell California Regional Water Quality Control Board 12 May 2010 Page 2 on-site on 6 April to observe destruction activities. On 5 April, WWT excavated around the well casing to a depth of approximately 4.5 feet, stockpiled the excavated soil next to the excavation, and cut the casing off 6 inches above the base of the excavation. On 6 April, WWT placed 2-inch diameter PVC tremie pipe down to approximately 82 feet bgs. Detonating cord was placed in the hole to 83 feet bgs with booster charges placed every 10 feet starting at 20 feet bgs. Prior to detonation of charges, a 10.3 sack mix (188-lbs sand to 94-lbs Type I or II Portland cement and 7-gallons water) sand-cement was pumped down the tremie pipe, filling the well to the top. Water displaced during grouting was placed in a drum onsite. After the charges were detonated, the grout slurry dropped approximately 10 feet. The well was then filled with grout to 6-inches above the top of the well casing, and the grout was allowed to set overnight. On 7 April, WWT backfilled the 4.5-foot deep excavation with stockpiled soil that was previously excavated from around the well casing. Wastes were left on-site as requested by Ripon Farm Services personnel. T&R will submit a Well Completion Report to the State of California Department of Water Resources, and SJCEH. If you have questions regarding the contents of this report, please contact Jeremy Gekov at (510) 874-4500, ext 527 or Patrick Hubbard at (925) 381-5381. Sincerely yours, ��P`GFO�� TREADWELL & ROLLO, INC. Jeremy C. Gekov OE ubbard, PG Senior Staff Geologist Principal Geologist 48430103.OAK Enclosures: Figure 1 — Site Location Map Figure 2 — Site Plan Attachment—Well Destruction Permit cc: Mr. Bud Den Ouden, Ripon Farm Services LLC Ms. Adrienne Ellsaesser, SJCEH