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of sand appropriate to the screen size will be placed in the annular space across the entire screened interval, and will extend approximately two feet above the top of the screen for the well A bentonite seal will extend two feet above the sand pack The monitoring well will be completed with neat cement from the bentonite seal to ground surface The well casing will be topped with a locking cap The wellhead will be contained in a watertight well box, either traffic rated and flush mounted or in a "stove-pipe" arrangement The boring logs will show well construction details The well will be developed after completion The development procedure for the well will consist of pumping or bailing water from the well until the water is visibly clear, the well goes dry, or until a maximum of ten casing volumes have been removed The wells will the be sampled with a disposable bailer Groundwater samples will be placed in 40 milliliter hydrochloric acid preserved VOAs Groundwater samples will be placed on ice for transport to the laboratory accompanied by chain-of-custody docu- mentation The well casing will be surveyed to the nearest 0 01 feet in elevation to a known benchmark Organic Vapor Procedures Soil samples collected at 5-foot depth intervals during drilling will be analyzed in the field . for ionizable organic compounds using a photo-ionization detector (PID) with a 10 2 eV lamp or an organic vapor meter (OVM) The test procedure will involve measunng approximately 30 grams from an undisturbed soil sample, placing this subsample in a sealed container (either a zip-lock bag or a masonjar) The container will be warmed for approximately 20 minutes (in the sun), then the head-space within will be tested for total organic vapor, measured in parts per million as benzene (ppm, volume/volume) The instrument will be calibrated prior to drilling using a 100-ppm isobutylene standard (in air) and a sensitivity factor of 55, which relates the photo-ionization potential of benzene to that of isobutylene at 100 ppm The results of the field testing will be noted on the boring logs PID and OVM readings are useful for indicating relative levels of contamination, but cannot be used to evaluate hydrocarbon levels with the confidence of laboratory analyses Laboratory Procedures Groundwater samples collected will be analyzed for the presence of total petroleum hydrocarbons calculated as diesel (TPHd), total petroleum hydrocarbons calculated as gasoline (TPHg), benzene, toluene ethylbenzene, and xylenes (BTEX), and the fuel oxygenates methyl tertiary butyl ether (MtBE), ethyl tertiary butyl ether (EtBE), di-isopropyl ether (DIPE), tertiary amyl methyl ether (TAME), tertiary butanol (TBA), ethylene I IChcvron1986321Reports\WP R-1,2,3,4 install doc A-2 l 1/2 t/00