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' Test Boring Results_ Robmhood Imgation Well Replacement ' Cle<1nup and Abatement Order No 5-00-707 EAI Project No 1232 3.0 TEST BARING The test boring for the RIW replacement well was drilled by Clark Well, Inc located in Stockton, California A permit for the test boring (#SR0024478) was obtained from the PHS- EHD The test boring was drilled using a mud rotary drill rig with an eight inch bit to a total depth of approximately 415 feet below grade surface (bgs) Drilling of the test boring commenced on November 14, 2000 and reached total depth on November 16, 2000 The well was logged on November 16, 2000 by Dewey Data (formerly Geo-Data Logging Services) Well logging consisted of Spontaneous Potential (SP), Lateral, and Resistivity logs (see Appendix B) Deflections observed on the SP log are related to electrochemical and ' electrokinetic effects taking place between drilling mud and formation For an SP deflection to exist, it is required that there be a minimum permeability which will allow ion migration between mud and formation Both the Lateral and Resistivity logs measure formation resistivity The electrode spacing on the Lateral log was 6 feet while the electrode spacing on the Resistivity log was 2 5 feet Thus, the Lateral log measured formation resistivity further ' from the well bore (deeper in the formation) than did the Resistivity log 3.1: Ground Water Sampling Ground water samples over selected intervals were obtained for analytical testing to determine if the encountered ground water was suitable for irrigation purposes Ground water samples were obtained by lowering a 3-inch steel pipe to the desired depth A 10-foot slotted section was attached to the bottom of the 3-inch pipe At the desired depth, a gravel pack was placed around the screened interval and a bentonite seal placed on top of the gravel pack An airlift ' system was then used to "pump" water from the formation until the formation water was relatively free of settleable material The airlift system was then removed and a submersible pump was placed across the screened interval A ground water sample for analytical testing was then obtained from the submersible pump On November 21 and 22, 2000, using the above described method, ground water samples were ' obtained from depths of approximately 350 feet bgs and 280 feet bgs An attempt to obtain a ground water sample from a depth of approximately 220 feet bgs was unsuccessful, as it appears that the well had caved in at this depth The ground water samples were logged on ' chain of custody record forms and delivered to FGL Environmental laboratory for analytical testing 3.2 Analytical Testing The water samples were analytically tested for the following chemical constituents (1) total petroleum hydrocarbons as gasoline (TPH-G) by modified EPA Method 8015, (2) volatile organic compounds (VOCs) including fuel oxygenates by EPA Method 8260B, and (3) carbonate, bicarbonate, chloride, sulfate, nitrate, calcium, magnesium, sodium, electrical econductivity, pH and boron, i e , general irrigation parameters The results of the testing are SAB 1232TESTBDRING -4- ENVIRONMENTAL AUDIT, INC.(, 1