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<br />EEC Project No. 1082030 <br />ASCI - Turnpike Reservoir <br />May 5, 2008 <br />Page 7 <br />Earth Engineering Consultants, Inc. <br />term groundwater monitoring. We understand the Turnpike Pit was previously a sand and <br />gravel mined pit and would conform to the requirements contained in "The General <br />Guidelines For Substitute Water Supply Plans For Sand and Gravel Pits Submitted To The <br />State Engineer Pursuant To SB 89-120 & SB 93-260 Section 3.0 Performance Standards." <br />The piezometers will be located outside the configuration of the lined reservoir to allow for <br />monitoring of groundwater levels, as a mechanism to evaluate the equilibrium of <br />groundwater on the outside portion of the reservoir versus water levels within the reservoir. <br />The piezometers/groundwater monitoring wells would be cased with 2-inch nominal <br />diameter Schedule 40, flush-threaded PVC pipe. The lower approximate 10-feet of the pipe <br />will consist of 0.020-inch slotted screen, while the upper portion, to approximate surface <br />grade elevations, will consist of 2-inch diameter Schedule 40, flush-threaded riser PVC pipe. <br />The piezometers will be backfilled with 10-20 silica sand to just above the top of the well <br />screen along with a bentonite clay seal placed above the silica sand. The remainder of each <br />monitoring well's annulus will be backfilled with on-site auger cuttings and/or non-shrink <br />grout. For protection purposes, a 4-inch by 4-inch by 4-foot length steel above ground well <br />cover device encased in a concrete apron will be provided for each piezometer/groundwater <br />monitoring well. <br />ANALYSIS AND RECOMMENDATIONS <br />Moisture Density Relationship-Standard Proctor Density <br />The existing in-situ dry densities for the overburden soils and the underlying bedrock stratum <br />generally ranged from 98 to 110 pounds per cubic (pcf), with a median of about 105 pcf. <br />Moisture contents typically ranged from 5 to 25 percent with a median of about 15 percent. <br />These dry densities and moisture contents correspond to consistency of medium stiff to stiff <br />materials, which are consistent with the penetration resistance blow counts, (SPT) indicated <br />on the boring logs included in the Appendix. EEC also performed standard Proctor density <br />(ASTM Specification D698) tests on composite samples of overburden materials and the <br />underlying bedrock collected during our field exploration.