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New Hope Soil Suitability June 26,2008 File No.2836-001.01 Page 3 disposal systems, and the construction of a new residence on each of the eight properties created. We also would expect that homes to be sited relatively near the Mokelumne, and given current regulations, leach field systems likely will be elevated to some degree. 4.0 GROUNDWATER INFORMATION We used a hand auger to assess the groundwater level at two locations in conjunction with our percolation testing. We engaged groundwater at a depth of 7'-6" along the unpaved driveway about 1,000 feet southerly of the southeasterly corner of the pear orchard, and at a depth of 5'-9" near the location of percolation test #5 (approximate middle of the property about 300 feet westerly of the easterly property line). Groundwater is thought to flow northwesterly within the general area of the site. There are wells at both described residences. We understand that wells in the general vicinity draw from a depth on the order of 50 feet. Water samples were obtained from the hose bib nearest each on site well. Each hose bib was _ purged for at least ten minutes prior to sampling. Six 40 nil VOC vials and one eight ounce nalgene container of water were obtained on February 27, 2008 from each hose bib using normal sampling protocol. Later than day, all samples were shipped to BSK Analytical Laboratories in Fresno under chain of custody. The contents of the nalgene bottles were tested for nitrates (NO3), and VOC vials for DBCP (Dibromochloropropane) and Ethylenedibromide. All analytes / were determined non-detect, indicating there is no nitrate or DBCP contamination of the d groundwater obtained from the wells. Chain of custody documentation is presented on the attached Exhibits 1 through 3, and the test data are attached as Exhibits 4 and 5. 5.0 SOIL PROFILE INFORMATION Each percolation test hole was logged by an Engineer from this office. The soils encountered in each hole are shown on the data sheets together with the data for each test. In general, the typical soil profile consists of clayey silty sand and sandy silt (SM/ML) extending from the ground surfaced to the maximum three foot depth of each test hole. The holes generally exhibited ,. increased granularity with depth, although we noted that predominately clayey soils were encountered in about the lower foot at percolation test sites 3 and 6. The soils encountered below depths of about five feet in our observation well holes were predominately sandy. We would expect predominately sandy soils to extend to significant depths. Owing to the predominately sandy nature of the soils at depth, and the fact that free groundwater generally is found within the sands, it is probable that leach field elements will need elevated slightly to provide for minimum clearance between the sands (probable groundwater location) and the points of discharge. In as much as the each property will be large, it should be possible to find areas of each site where stratification is most favorable to separation between the point of discharge and the depths of predominately sandy soils (likely the free groundwater level). V