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Tow Mr. Shawn Kelley Page 3 f December 8, 1999 i The boreholes will be drilled with truck mounted hollow stem augle or rest push drilling equipment. All drilling equipment and sampling tools will be cleaned prior to'artivfng and before leaving the site. The sample devices will be advanced to the desired sampling depth interval, and a drive split spoon sampler will be driven into undisturbed soil. The sampler will then be retrieved and dissembled, and the soil filled brass finerx if retained for chemical analysis, will be sealed with Teflon®paper and plastic end caps, labeled, logged onto chain-of-custody forms and place in a chilled ice chest. Following soil sampling each bore hole will be prepared for reconnaissance groundwater sampling using temporary'/. inch PVC well casings. The boreholes will be logged using the Unified Soil Classification System under the supervision of a registered geologist using the attached Geoscience protocols Wright has developed for drilling, sealing, temporary well construction, well construction and sampling. Additional litho logic information will be collected to describe the subsurface geology. The samples will�be collected at minimum five-foot - intervals, at intervals of obvious contamination (field screened by vapor pid meter) and at stratigraphic features of interest. Borehole depths are anticipated to lie about 15-feet deep for this J 1 Creconnaissance. Reconnaissance Groundwater Samolim! Each borehole will be purged using calculated welUolumes.based upan the depth to water in each casing Depth to groundwater meas-ure �-rents will be made to the nearest one-one hundredth of one foot from e existing grade, and also checked for the presence of separate phase pioduct. The groundwater sample will be carefully collected with a clean bailer and poured into the appropriate laboratory prepared container with minimum cavitation. Each water sample will be labeled, logged onto a chain-of-custody fort, and placed in a chilled ice chest for transportation to a state certified',laboratory for analyses as indicated below. Upon completion of the borehole drilling and collection of information, the boreholes will be backfilled with gout, placed from the bottom to top of the borehole The paved surface will be patched wit gri�uick setting concrete or asphalt,to match existing. In addition, the borehole stratigraphic and chemical analytical data will be reviewed to ascertain the need for and positioning of groundwater monitoring wells. Should groundwater-monitoring wells be required then the following well installation procedures would be used Chemical Analysis Up to six (6) capillary fringe soil samples, six(6)vadose zone soil samples, one (I) aquitard.sample and six(6) groundwater samples will be analyzed at a State certified analytical laboratory from the exploratory borings. These samples will be tested for the following: Total Petroleum Hydrocarbons as Gasoline (TPHG)Diesel (TPHD),Benzene(B). Toluene(T'),Ethyl-benzene(E)and Xylene(X),Methyl-tert-butyl- ether (MTBE) and fuel Oxygenates, 1.2 Dichloroethane and Ethylene Dibromide using EPA Methods 3510/8015, 8020,and 8260. The analyses will be run on a normal turnaround 1 �oPePHASE TWO r itorin Well Installation T monitoring wells will be installed using the six exploratory boreholes data to locate time wells for lon term plume monitoring. The wells will be cased with Schedule 40 PVC casing threaded together; ues will not be used. The slotted interval will be a 0.020-inch slot and the annular space around the slots will be backfilled with2-size sand. Previous experience has shown this to be a reliable well design in fine grained and stmt' ed depositional environments. Final well design will be modified to the site- specific conditions encountered in the borehole during drilling. Once the aquifer strata have been defined,