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An important concern associated with the environmental assessment of agricultural properties is the issue of buried pesticide containers. It was an occasional practice to dispose of containers by this method many years ago. To detect these types of underground artifacts is difficult even with the use of ground penetrating radar or other types of non-intrusive, subsurface analyses. The land surface did not exhibit visual indicators for buried containers such as surfacing of product residue, soil mounding or soil depressions. The static groundwater is found approximately eight feet under the property. This is considered a comparatively shallow groundwater elevation. Shallow groundwater can be easily impacted from pesticides or nitrogen in the form of nitrates. However,the on-site soils consist of a medium to high clay content soil which can attenuate agrichemical contamination in comparison to a sandy soil. The groundwater directional flow is probably towards the Tom Paine Slough and the Delta to the north. To evaluate agrichemical residues as a nonpoint source of potential contamination, pesticide records from the previous two years were obtained. The science of pesticide residues in soil, air, surface water and groundwater is extremely complex and variable. Environmental models which attempt to predict pesticide behavior and transport in the environment are beyond the scope of this investigation. It has been clearly evident over the last four decades that the riskibenefit ratio regarding pesticides has been overwhelming benefit and comparatively low risk to the United States population, as a whole. Environmental fate data for the following pesticides which were applied to the subject property was obtained from the Illustrated Handbook of Physical-Chemical Properties and Environmental Fate for Organic Pesticide Chemicals: Dual. Common name: Metachlor. Half lives in the environment: Groundwater: degradation time 500-1000 days (d). Soil: Half-lives in clay loam are 15-38 d. Phytolysis: Under optimum exposure conditions to natural sunlight, half life is approx. 8 d. Sevin. Common name: Carbaryl. Half-lives in the environment: Air: 12.6 hrs. Surface water: 3.2-200 hrs. Groundwater: 3.2-1440 hrs. Soil: 97-251 hrs in dry soil, 4458- 4688 hrs in saturated soil. Dimethoate. Half-lives in the environment: Air: 0.469-4.69 hrs. Surface water: 264-1344 hrs. Groundwater: 528-2688 hrs. Soil: 264-888 hrs. Orthene. Common name: Acephate. Half-lives in the environment: Soil: selected field half-life of 3.0 d. Hydrolysis: half-life of 60 hrs 4 va!!ey Ag Pfsearck