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rs r (§4.2) Any of the above land use could create environmental concerns that may be discovered in the future. Environmental concerns within the Delta would primarily be from the over-application of fertilizers and pesticides. (§3.1, 3.2,3.3) This Study specifically addresses the septic system that will serve the new residential structure Unit #4, as directed by EHD. Therefore, Sections §3.1, 3.2, 3.3, 3.4, 3.5,3.6 are not applicable. (§3.4) As referenced, the subject property is in an area designated as "High Water Table"by EHD's map denoting the various soil types and septic system requirements throughout San Joaquin County. Consequently, only leachlines or filter beds are allowed to be installed in this area of the County. (§ 5.1 and 6.0) SOIL PROFILE AND PERCOLATION TESTING (§ 5.4) The proposed area for the primary and reserve replacement leachfield areas consists of soil material imported from various locations on Mandeville Island. Soil material was imported to raise the elevation of this area for the storage of tractors, farming equipment and implements, along with associated buildings to prevent flooding. It was stated by Mr. Clint Womack of C.C.R.C. Farms that he has never seen this "raised area" flood in the eight years he has been farm manager for the company. As evidenced in the attached photographic plates, the proposed leachfield area is four-to-five feet higher than the surrounding farmland. The exact elevational difference was not determined by Chesney Consulting or Quartaroli and Associates because the main issue concerning EHD is the depth to groundwater, which is discussed below. (§ 5.2, 5.3, and 5.4) A Log of Boring using the Unified Soil Classification System (USCS) as observed in the 24 and 42-inch deep perc test borings is found on the EHD PERCOLATION TEST DATA SHEETS. Generally, the soils show a highly compacted silty, fine sandy soil, on the surface and'down to 24 inches, then a consistent silty fine-to-medium sandy soil from approximately 30 inches down to 42 inches. Below six feet is a highly organic, peat soil as observed in the backhoe test pit excavated to determine underlying soil morphology and the static water table depth. (§6.1) Percolation testing was conducted near the center of the proposed leachfield area, as illustrated in the photographs. The photographs also illustrate various pieces of equipment and other discarded items from farming operations. Most of these items are on pallets. Typically, heavy equipment(e.g., forklifts, etc.)were used to deposit discarded items in this "boneyard" area. This unquestionably contributed to the observed soil compaction that was evident in the backhoe test pit, the shallow 24-inch deep pere test results, and the infiltration test results. (§ 6.2, 6.3 and 6.5) On February 13, at 0900 hrs, one shallow perc test boring of 24 inches and 42 inches in depth were hand-drilled. It was anticipated that a pressurized filter bed may have to be installed for effluent disposal. This 24-inch deep boring represented percolation which would occur at the soil-effluent interface under a filter bed. The 42-inch test boring was representative of the maximum leachline trench depth allowed by EHD. Page -3- Chesney Consulting