Laserfiche WebLink
NOA Drywell Closure and Investigation Work Plan <br /> Page 6 of 16 <br /> March 18, 2014 <br /> Revised March 20, 2014 <br /> 3.3 Health and Safety Plan <br /> ' Please see the site-specific Health and Safety Plan for sampling and well destruction activities, <br /> included as Appendix B. <br /> 4.0 SAMPLING AND ANALYSIS PLAN <br /> 4.1 Sampling Objectives <br /> The objective of the groundwater and soil sampling around the drywells at the subject property <br /> is to confirm the presence or absence of contamination as a result of the industrial use of the <br /> drywells. NOA will collect the groundwater and soil samples under the supervision of NONs <br /> California Registered Professional Geologist and the San Joaquin County Environmental Health <br /> Department. Soil and groundwater sampling will be performed concurrent with overdrilling <br /> activities. Each drywell will be overdrilled, sampled, and grouted separately. One (1) drywell will <br /> be completely overdrilled, sampled and grouted prior to the start of well closure and sampling <br /> ' activities for the other well. <br /> NOA proposes to collect all soil and groundwater samples under the direct supervision and <br /> oversight of EHD. Samples will be picked up by the analytical laboratory directly; all laboratory <br /> correspondence and results will be sent exclusively to EHD. <br /> 4.2 Sampling Locations and Depths <br /> 4.2.1 Groundwater <br /> Release to the drywell was terminated on March 6, 2014. Groundwater in the drywells has <br /> consistently dropped since this event; groundwater is currently below the vertical extent of the <br /> drywells. It is anticipated that on-site groundwater levels will drop to approximately seventy <br /> (70) feet bgs by the sampling event. <br /> Groundwater samples will be collected from the two (2) drywells. Since groundwater is below <br /> sampling depths in the drywells, groundwater samples will be collected once drilling and soil <br /> sampling activities reach groundwater. <br /> Six (6) groundwater samples will be collected from each of the two (2) drywells. One (1) <br /> additional sample will be collected from one (1) of the drywells for Replicate Samples Quality <br /> Assurance/Quality Control purposes. A total of thirteen (13) groundwater samples will be <br /> collected. The drywell and sampling locations are shown on Plates 5 and 6. <br /> 4.2.2 Soil <br /> If present, one (1) sediment/sludge sample will be collected from the Concrete Cure Room floor <br /> drain at the approximate vertical extent, one and one-half (1.5) feet bgs. The pipe drainage line <br /> is a contained system and there is no reason to suspect leakage. Therefore, no soil samples will <br /> be collected beneath the vertical extent of the drain. <br /> 902 Industrial Way•Lodi,CA 95240-209.367.3701 •Fax 209.369.4228 02014 Neil O.Anderson&Associates,Inc <br />