Laserfiche WebLink
GEOTECHNICAL <br /> NEIL O. ANDERSON ENVIRONMENTAL <br /> A N D A S S O C I A T E S INSPECTIONS ! TESTING <br /> LABORATORY SERVICES <br /> POOL ENGINEERING <br /> January 17,2006 r � P�j '/ I G N <br /> E <br /> NOA Project Number.E05089A U u JAN 8 2006 006 <br /> Dolores Lim ENVIRONMENT HEALTH <br /> 38746 Cherry Lane Road PERMIlTjSERVICES <br /> Fremont,CA 94536 <br /> Subject. Soil Suitability Study <br /> San Joaquin County EHD Reference No.s:PA-0400791 and SR0043522 <br /> 23403 Hansen Road <br /> Tracy,CA 95304 - <br /> Dear Mrs.Lim, <br /> Our office recently received a letter dated December 12,2005 from the San Joaquin County Environmental <br /> Health Department Regarding the above referenced Soil Suitability Study. According to the EHD,the study <br /> has "some deficiencies and is incomplete." A copy of the EHD letter is attached. In the checklist-comments <br /> section of the letter,EHD staff indicated the following: <br /> Address the 76.5 PPM NO,well water sample, the groundwater being equal or less than 10 feet, and the <br /> fad percolation rate suggesting the possibility of an Alternative Engineered Septic System deagn. Also <br /> discuss the pos ibi#i v of requiring an engineered or alternative septic system to mitigate further degradation of <br /> groundwater with respect to nitrate contamination. <br /> I discussed these issues with your husband on January 17,2005. We agreed that an addendum letter should <br /> be submitted to the EHD proposing a modified filter bed septic system. Details regarding the system follow <br /> later in this letter. This approach may satisfy some of their concerns. The other issue is the high level of <br /> nitrates in the well water. We also discussed the elevated nitrate level found in drinking water as a potential <br /> health risk. I suggest that you contact EHD to discuss any possible repair technology or replacement options <br /> for the well. Being a potential health risk,you may wish to use bottled water for drinking. <br /> The remainder of the letter addresses the EHD concerns. A copy of this letter will be sent directly to the <br /> appropriate EHD Staff for their review and approval. <br /> Regarding the 76.5 mg/L-NO3well water sample: <br /> A high level of nitrate in ground water from an onsite well indicates two potential issues. The first issue is <br /> the suitability of the water quality from the well for drinking and the second issue is that whether the aquifer <br /> has elevated levels of nitrogen. Both issues were addressed in the report See sections 4.2,4.4 and 7.0. <br /> Regarding the "fast"Percolation Rate: <br /> The percolation rates observed during the test were found to be 3.6 and 9.6 minutes per inch. In the EHD <br /> Conditions For Approval Letter,the percolation test should be performed according to the Manual of Septic <br /> Tank Practice(U.S. Department of Health Services, 1967). Please note that the Manual of Septic Tank <br /> LODI ■ SACRAMENTO ■ MODESTO ■ RENO <br /> ENVIRONMENTAL DIVISION 902 Industrial Way,Lodi,California 95240 ■209.367.3701 0 209.369.4228 fax ■w .noanderson.com <br />