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logs. A physical description of the encountered soil characteristics (i.e. moisture content, consistency, odor, color, etc.) and soil type as a function of depth are indicated on the boring logs. In addition, the sample recovery and sampler penetration are also noted on the boring logs. The sampled soils are classified in accordance with the USCS. STANDARD PROCEDURE FOR WELL CONSTRUCTION Wells are constructed by inserting or tremmieing well materials through the annulus of the hollow stem auger. In general, the wells are constructed with 5 to 20 feet of screen, with schedule 40 PVC blank casing to ground surface. The well screen consists of 0.010-inch slot PVC casing that is filter packed with Lonestar 2/12 sand or equivalent. Where shallow groundwater is encountered or perched water dictates otherwise, the screen is adjusted, as appropriate, to maintain a proper seal at the surface (minimum three feet) and to avoid penetrating low permeable horizons or aquicludes. All wells are installed in accordance with the conditions of the well construction permit issued by the regulatory agency exercising jurisdiction over the project site. Once the borehole has been drilled to the desired depth, approximately six inches of filter sand are tremmied to the bottom of the boring. The well screen and blank well casing are then inserted through the annulus of the hollow stem augers. The well screen is sand-packed by tremmieing the appropriate filter sand through the annulus between the casing and augers while slowly retracting the augers. During this operation, the depth of the sand pack in the auger is continuously sounded to make sure that the sand remains in the auger annulus during auger retraction to avoid short-circuiting the well. The sand pack is tremmied to approximately two feet above the top of screen. Following construction of the sand pack, a three to four-foot thick bentonite seal is tremmied over the sand and hydrated in place. The remainder of the borehole is backfilled with bentonite grout, pellets, or chips. The wellhead is then capped with a locking cap and secured with a lock to protect the well from surface water intrusion and vandalism. The wellhead is further protected from damage with traffic a rated well box in paved areas or locking steel riser in undeveloped areas. The protective boxes or risers are set in concrete. The details of well construction are recorded on well construction logs. STANDARD PROCEDURE FOR DIRECT-PUSH DRILLING Prior to drilling, boring locations were marked with white paint and cleared for underground utilities through Underground Service Alert (USA). In addition, the first five feet of each borehole was air knifed or hand- augured to evaluate the presence of underground structures or utilities. Once pre-drilling efforts to identify subsurface structures was complete, pre-cleaned drill rods were advanced using a drill rig for the purpose of collecting samples and evaluating subsurface conditions. Upon completion of drilling and sampling, the drill rods were retracted, and the boreholes were backfilled with cement grout. In areas where the borehole penetrated asphalt or concrete, the borehole was capped with an equivalent thickness of asphalt or concrete patch to match finished grade. During the drilling process, a physical description of the encountered soil characteristics (i.e. moisture content, consistency, odor, color, etc.), drilling difficulty, and soil type as a function of depth was described on boring logs. The soil cuttings were classified in accordance with the Unified Soil Classification System (USCS).