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NOW § 3.4 Description of all past off-site potential and/or known above and below ground sources of contamination identified in the area of the project site that has or may impact the project site includes: Information conveyed by the March 8, 2007 Envisions Program Documents illustrating no listings on or in proximity to the subject property. The closest Leaking Underground Storage Tank is on Yosemite Boulevard, 2000 feet to the west,which can be considered crossgradient to the subject property. In addition, the Envisions Program Documents show that Mr. Davis has an Underground Storage Tank at his main RV sales facility approximately one-fourth mile to the west from the property on Yosemite Boulevard. This can also be considered crossgradient to the property. These tanks and any leaking contents could not affect the property due to the distances involved. Agricultural spray drift (non-target) from the nearest agricultural production land affecting the property could be a possibility, since agricultural production still occurs to the east and to the south. The region has been, and continues to be intensely farmed, so nitrate contamination to the underlying groundwater from nitrogen fertilization is always a possibility. The science of pesticide residues in soil, air, surface water and groundwater is extremely complex and variable. Environmental models that attempt to predict pesticide behavior and transport in the environment are beyond the scope of this investigation. Pesticides with long half-lives that may have been used or drifted onto the property decades ago,primarily DDT, may be of an extremely slight concern. DDT was used extensively / throughout the agricultural fields of the San Joaquin Valley and degradates of DDT can be found in nearly all these soils. Previous Exposure Assessments made on typical San Joaquin Valley soils suggest an extremely low probability of adverse health effects from soil DDT/DDD and DDE concentrations (if the concentrations even exist). The environmental fate data are presented below for DDT, and its degradates DDD and DDE. DDT. Common name:Agritan,Anofex,Azotox,et al. Half-lives in the environment: Air: 17.7 -177 h. Surface water: 73.9 h for a pond 1 in deep.Degradation half-life of about 10 yr-average from loss rates determined in Lake Michigan. Groundwater: 16 d to 31.3 yr. Sediment: 3 to 5 yr Soil: 2-15.6 yrs based on observed rates of biodegradation in aerobic soils under field conditions. Avg.half life of-12 yrs in 3 different soils for -50 ppm in soil.(conversion of p,p'-DDT to p,p'-DDE). Environmental Fate Rate Constants or Half-Lives: Volatilization: Half-life of 3.7 d for water depth of 1 m,from soil w/h-1 of 578 h Oxidation:Photooxidation half-life of 168-8400 h in water, 17.7-177 h in air Hydrolysis: Estimated first-order half life of 22 yr Biodegradation:Aqueous aerobic half-life of 2-15.6 yrs Page -5- Chesney Consulting