SU0004494 SSNL - Laserfiche WebLink

Home Browse Search

r Richland Communities Inc. 5943.5.001.03 1481 West Manila Road,PA-04-266 (MS) September 9,2004 SEPTIC FIELD SOIL SUTTABILTTY STUDY Page 3 located to the northwest of the residence at 1481 Manila Drive (Figure 2). The water sample was collected directly from af ua cet outside of the shed From the well head, water passed through a pressure tank before being pumped through the faucet located outside the shed. The water sample was collected in pre-cleaned laboratory containers supplied by the testing laboratory. No purging of the water system was performed. Following sample recovery, the r sample containers were labeled and placed in an ice cooled chest for transport under documented chain of custody to Sequoia Analytical inacramento, California for analysis of 1,2-Dibromo-3-chloropropane (DBCP) and Nitrate as N 3. The result of the laboratory analyses did not reveal detectable concentraa iMM 5T BCP and Nitrate as NO3 above the laboratory detection limits of 0.01 ug/L and 1 mg/L, respectively. The laboratory detection limits are below the EPA Region 9 Preliminary Remedial Goals for tap water. The Sequoia Analytical laboratory results are attached as Appendix C. Percolation Test Preparation Two 12-inch-diameter percolation test holes (one per parcel) were drilled to a depth of 36 inches below the existing ground surface at the locations shown on Figure 2. Following drilling, the sides of the holes were scraped to remove smear from the drilling process and loose material was removed from the bottom of each hole. Preparation of the percolation test hole began by placing two inches of pea-sized gravel in the bottom of each hole. A four-inch-diameter perforated drain pipe was then placed in the hole and was surrounded by approximately two feet of 3/4-inch diameter drain rock. Water was added to the hole up to the ground surface (36 inches) and _ allowed to pre-soak overnight. Per Mr. Justin Hess (San Joaquin County Environmental Health Specialist), due to shallow groundwater at the site, no deep percolation tests were required. ` Percolation Testing The percolation tests were performed at the property on August 25 2004. Upon completion of the overnight presoak, The holes were refilled with water to a level approximately 6 inches above the gravel base at the bottom of the pipe. The water level was measured every 10 minutes for a 30-minute period. After the 30-minute period the water level was reset to approximately 6 inches above the gravel base. Since six inches of water did not all percolate in the first 30 minutes in either location, the measurement interval was increased to 30 minutes and the process was repeated for four hours. The last stabilized .. measurement was performed under the observation of Mr. Ray Borges, a San Joaquin County Environmental Health Specialist and was used to determine the peicoRion rate of 7.6 minutes per inch (mpi) for Test Hole #1 located on Parcel 1 and 12.5 mpi for Tes :a located on Parcel 2. The completed San Joaquin County percolation test rate Form lc (EHD 42-02-003 revised 5/7/02) is attached as Appendix D. r r