SU0006112 SSCRPT - Laserfiche WebLink

Home Browse Search

Fro ALUATION OF PAST AND CURRENT SOURCES OF NTAMINATION IDENTIFIED AT OR NEAR THE SITE ANDCOMMENDATIONS FOR FURTHER ACTION d §4.1 Evaluation of each potential and/or known source of contamination identified in the above Sections have been discussed in the respective Sections to facilitate the transfer of information to the reader. Recommendations are proposed in Section 5.0,below. ✓Based upon the State Water Resources Control Board- GeoTracker System, there are no records of under ground (UST) storage tanks or Leaking Underground Storage Tanks(LUSTs)near the subject property. This is illustrated on the attached GeoTracker Site Map,which shows the nearest LUST to be in the town of Lockeford, eight miles to the southwest. -/The Inactive UST Facility Inventory List and the Underground Storage Tank Site Mitigation Database List,both from EHD, are found in Appendix B. The Lists show that there is no listing for the Olson Ranch, or the property address. Potential environmental impacts from past,present or future facilities within a one mile radius of the property are unknown at this time,but unlikely. ✓The on-site irrigation well has a fertigation system. Fertigation is the precise method of dosing fertilizer in prescribed amounts through irrigation(hence the term"fertigation") applications so that fertilizer is applied accurately, corresponding with crop requirements. A backflow prevention device is on the irrigation well piping system. Appendix C lists certified backflow prevention devise testers that can verify this backflow prevention device. /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. However,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). ince the subject property is located outside of what would be considered agricultural farmland during the time that DDT was used, it is unlikely it exists in the property soils. Nevertheless,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 detemrined in Lake Michigan. Groundwater: 16 d to 31.3 yr. Sediment:3 to 5 yr Page-5- Chesney Consulting