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feet below existing grade. Estimates of soils density were based on the resistance of the hand auger probes. Soil classifications were determined in accordance with the American Society for Testing and Materials (ASTM) procedures by examining the hand auger probe cuttings. An assessment of the site grading and drainage was made. The building site appears to be poorly drained. The lot appears flat. Grading work will be needed to provide positive drainage away from the building. Water was encountered at a depth of 2 1/2 feet below existing grade. We understand there will be a minimum of 3 feet elevation difference between the lowest floor and groundwater level. We recommend that the soils below the footings and column pads be excavated one foot below footing grade and replaced with free drainage course stabilizing aggregate (3/4 inch to 1 1/2 inches rock) Based on the results of our visual observation, it appears that the groundwater may have an impact on below grade walls on the site. However, we recommend that an exterior perimeter foundation drain be installed. The foundation drain should consist of a 4 inch diameter perforated flexible "sock-type" p.v.c. pipe surrounded by rock and wrapped in filter fabric. We recommend that the drain discharge by gravity at a maximum of 5% slope from the house to daylight. An interior sump pump could also be used to discharge water from the foundation drain. Roof downspouts should be extended to outfall past the backfill. In addition, the below grade walls should be damp proofed with bituminous material, 6-mil poly, or approved damp-proofing material from the top of the footings to the ground level. A minimum of 4 inches of clean, washed sand should be placed beneath the floor slab to prevent capillary rise of moisture. The finished exterior wall backfill should be placed so that any surface water will drain away from the house at a slope of 5%. SUMMARY Based upon the result of our observation, it appears that groundwater may have an impact on below grade walls on this site. However, site grading, damp proofing, and exterior foundation drains are required to alleviate any potential problems. It should be noted that standard penetration test borings with power equipment were not taken to evaluate the soils at depth. However, visible soils and the results of the hand auger probes indicate that the risk of detrimental settlement due to unsupportive soils at depth is minimal. In our opinion, it is reasonable that this risk be assumed by the owner. It should also be noted that fluctuations in the level of the groundwater can occur due to Report of Observation L T.T.Project #06-158 May 18,2006 Page 2