SITE INFORMATION AND CORRESPONDENCE

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Mr. Verrill Norwood -2- 6 August 1996 Stormwater Collection Pond The stormwater pond is not lined as stated, and there are currently no requirements for discharge to this pond. The Standard Industrial Code (SIC) for the All Pure facility is category 28, which requires All Pure to have a stormwater permit for any discharges of stormwater to surface water. To continue operating without a stormwater permit All Pure must show there is no chance of an overflow from the stormwater pond to nearby surface water during a 100-year storm event. Mr. Tim Vickers, Plant Manager, informed me during my 20 March 1996 visit to the site, that the stormwater pond also receives water containing water softener. The sample I collected from this pond on that day had low levels of trihalomethanes. If water other than stormwater is to continue being discharged to this unlined pond, All Pure must submit a Report of Waste Discharge and obtain Waste Discharge Requirements. SCOPE OF WORK Task 1 - Management of Free Liquids, Liners, and Sediments After the free liquids have evaporated from the impoundments and before the liners are removed, the condition of the pond liners should be documented with photographs and the photographs included in the report of soil sample results. Task 3 - Soil Sampling The proposal for soil sampling does not provide adequate details on the sampling procedures. Details must be provided on the sampling equipment, diameter of the boreholes, precautions used to prevent cross-contamination of samples, method of cuttings disposal, and method of sample preservation. The proposal to collect one soil sample from the bottom of each pond is acceptable, but depending on the depth of the pond bottoms and the depth to ground water, the proposal to sample only at depths of two to three feet below the bottoms of the ponds may not determine the vertical extent of soil contamination. As my 9 May 1996 letter stated, soil samples should be collected at a minimum of five-foot intervals and at significant changes in lithology from the ground surface to the water table. This vertical profiling should be conducted at all sample locations, both within and outside of the impoundments. As my letter also stated, soil gas samples should be collected from each pond with an active soil gas sampler. All Pure must propose sampling locations, sampling methods, and analytical methods, and provide details about the equipment to be used and the detection limits to be achieved. The work plan states that the small lined pond closed in 1994 was backfilled with native soil. If the source of the fill material used to fill this pond cannot be identified, a soil sample needs to be collected from within the fill as well as below the fill.