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The predominate wind direction through the region is to the east-southeast. West- northwest, or upgradient wind shed is composed of agricultural production land including row crops and some orchards. Agrichemicals must not be applied during windy conditions, thus ensuring that the likelihood of impact to the property from unintended pesticide drift is somewhat unlikely, but still a possibility. Although DDT was b "e to 2, its presence in San Joaquin Valley soils is indicative of its long half-lif f 15.6 years. )Consequently,there may be extremely small concentrations o DDT, and it egradates in the subject property soils from farming operations that ma aken place on the property decades ago. Any minute residual pesticide concentrations are inconsequential in my professional opinion. 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 m 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 It 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 DDE. Common name: DDE(p,p'-DDE;o,p'-DDE),product of DDT degradation. Half-lives in the environment: Air:Atmos.transformation lifetime est.to be< 1 d. Surface water: Hydrolytic half-life of >120 yr,est. half-life>300 d in lakes. Groundwater:N/A Sediment:N/A Soil: Field half life of 1000 d Biota: Elimination half-life of 340 d(rainbow trout),300 d for birds. Environmental Fate Rate Constants or Half-Lives: Volatilization:N/A Oxidation:N/A Hydrolysis:>120 yr DDD. Common name: DDD,TDE(tetrachlorodiphenylethane),product of DDT deg. Half-lives in the environment: Air: 17.7-177 h Surface water:2-15.6 yr. Groundwater: 1680-270,000 h based on anaerobic soil study data Sediment:N/A Soil: Field half life of 2-15.6 yrs based on observed rates of biodeg. of DDT Biota: 119 hr in mussels. Environmental Fate Rate Constants or Half-Lives: Volatilization:Aquatic approx. 1 mo.Oxidation: Aquatic half-life approx.22 yr Page -5-