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F t concern associated with the environmental assessment of open properties is the ed pesticide containers or discarded items. It was an occasional practice to dispose of r discarded items by this method many years ago. To detect these types of artifacts is difficult even with the use of ground penetrating radar or other types of e, subsurface analyses. The land surface did not exhibit visual indicators for buried containers such as surfacing of product residue, soil mounding, or localized soil depressions. It is unlikely anything was buried, particularly in the cropland of the subject property since it has always been farmed and the water table is very high. It is usually only after a contaminant plume has impacted a domestic well that underground containers are discovered. If buried items are discovered at any time, the Environmental Health Department must be contacted immediately. Two electrical transformers are found on a pole next to the residential structure. It appears to be a newer type of transformer; therefore, it probably does not contain polychloride biphenyl (PCB) laden oil. The transformers do not show any sign of leakage. If these transformers were to leak or explode, it would be the responsibility of the transformer owner(P.G. & E) to mitigate any environmental contamination. From previous soil suitability studies and other soil and groundwater investigations in this locale, l� s. it is known that there can be high concentrations of nitrate in the underlying water table and l drinking water aquifers. High nitrate concentrations in the groundwater in this region are attributable to agricultural fertilizer inputs, and organic matter decay that has occurred in the Delta region for centuries, impacting the notably shallow groundwater. PUBLIC ENVIRONMENTAL RECORD/DATA SOURCES Static groundwater is found approximately 5 feet under the property. This is based upon water in the adjacent unlined irrigation laterals. The 1999 Lines of Equal Depth to Groundwater map and the 1999 Lines of Equal Elevation of Groundwater do not illustrate the groundwater depth or directional flow for the Delta region. From recent groundwater studies done at a nearby dairy, it is known that the groundwater directional flow is to the east and southeast. A groundwater depth of 5 feet or less, can be considered a very shallow groundwater elevation which can be readily impacted from point source hazardous materials releases, agrichemicals such as pesticides/ herbicides, or nitrates from fertilizers. However,the degree of impact from agrichemicals can be mitigated when there are intervening layers of clay soil down to the static water table depth. The Delta area obviously has heavy peatland soils, as discussed below, that may impede agrichemical impact and possibly promote denitrification. There are no records of underground storage tanks(USTs) at the subject property address. This is illustrated on the attached GeoTracker Site Map,which shows no Underground Storage Tanks (USTs)or Leaking Underground Storage Tanks (LUSTS)tanks near the site. Underground Storage Tank and LUST sites are shown approximately 2.5 miles to the east of the property. EHD LOP/NON LOP Sites List indicate two sites that are more than two miles to the west: Terminous Market, 13889 West Highway 12 and Tower Park Marina, 14900 West Highway 12. These tank sites can be considered downgradient and upgradient, respectively, and impossible to impact the subject property. Potential environmental impacts from past, present or future facilities within a one mile radius is unknown at this time,but highly unlikely. Page -3- Ch mq Consulting