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Project No 014-95262 Page No 10 apparently laterally continuous sandy zone from approximately 30 to 35 feet bgs, no CPT soundings were conducted at the locations proposed for samples KHP-7, KHP-8, and KHP-9 located in the southern portion of the protect site The sandier zone at this depth was apparently present at these locations also This conclusion is based on a sunilar ease of groundwater sample collection at these sites as compared with sites at which CPT soundings clearly delineated the sandier unit 7.4 Hydropunch (or Equivalent) Water. Samnluie 7.4.1 Samphng Methods J Based upon the soil profile information provided by the CPT soundings, depth discrete water samples were collected from favorable (sandier) soil units An initial attempt at location HP-6 to collect a a water sample from a depth of 24 feet bgs. using the Hydropunch II sampling tool resulted in no water entering the sample chamber After review of CPT logs, another attempt was made by pushing the Hydropunch to a depth of 33 5 feet bgs Recovery of groundwater into the sample chamber after bailing was very slow resulting in a minimal sample volume being collected i It was anticipated that the very fine nature of the soil was causing blockage of the Hydropunch screen Therefore as an alternative method, a sacrificial tip was placed on standard drill rod and pushed Soto the target depth The rod was pulled back releasing the tip and forming a cavity into which groundwater could collect A bailer was then lowered down the hollow rods to collect water samples as with the standard Hydropunch 11 method This alternate method was used at all subsequent groundwater sampling locations Recovery of groundwater increased but this alternate sampling method also resulted in substantial amounts of sediment being collected with groundwater in the sample bottles 7.4.2 Groundwater Chennstry Analytical data from groundwater samples collected using direct push methods are presented in Table 3 This data is also presented on Figure 5, which shows concentrations of detected constituents at each of the sample locations Samples were collected from depths ranging from 33 5 to 41 feet bgs and averaged 37 5 feet bgs Samples were analyzed for one or more of the following constituents, depending on the area investigated, electroconductiviry (EC), chloride (Cl), nitrate (NO3) ammonia (NH3), phosphate (PO4), sulfate (SO4), pH, TPH-D, total recoverable petroleum hydrocarbons (TRPH), and volatile organic compounds (VOCs) One sample (KHA-9) was also analyzed for semi-volatile compounds Please refer to Table 3 for the specific analytical methods used Sample KHP-2, assumed to represent background conditions, exhibited moderate EC and chloride, low nitrate and phosphate, non detected ammonia, moderate sulfate and an alkaline pH TPH-D was KRAZAN&ASSOCIATES, INC Offices Serving the Western United States vszss vsx