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D.3 Groundwater Sampling Plan ' Quarterly groundwater sample collection and handling procedures shall utilize the following protocols. ' (i) A "Well Purging and Sample Log" shall be completed for each sampling site. An example log is included in Appendix C. ' (ii) Upon arrival at the site, the water level in the well shall be measured by electronic sounding or steel tape and recorded to the nearest 0.01 feet. ' The sounder or tape shall be cleaned with dilute bleach solution prior to each use to minimize coliform contamination. (iii) Multi-meter probes shall be calibrated at each site using appropriate standards. Preliminary measurements of specific conductance are made to select the calibration standard closest to the specific conductance of the well water (within 125 to 1,500 µS/cm, depending on the well water conductance). ' (iv) When well yield permits, wells shall be purged and sampled using a submersible pump and dedicated plastic tubing at each well. The submersible pump shall be triple-rinsed with de-ionized water between ' wells. A minimum of three well casing volumes shall be evacuated from each well prior to collecting the sample; the casing volume is calculated from the depth to water and casing diameter and depth. Field parameters (pH, specific conductance, temperature, dissolved oxygen, and oxidation- reduction potential) shall be monitored using a multi-meter and flow cell during purging (i.e., at the beginning and then following each casing volume). Stabilization of these parameters indicates the collected water is representative of groundwater. ' (v) If well yield is insufficient to produce three-casing volumes in a reasonable time, the well shall be evacuated and then sampled after recovery. (vi) When conditions allow, purge water shall be spread on land surrounding the well or an approved land application area. Otherwise, purge water shall be collected in a tank or drum and transported for spreading at the ' nearest land application area. Discharge to stormwater drains or surface water features is not acceptable. (vii) Following the collection of all other samples, the submersible pump shall be removed and the sample for total coliform analysis collected using a new disposable bailer. (viii) Samples to be analyzed for dissolved constituents are filtered in the field using 0.45-pm capsule filters. The capsule filters are certified to meet EPA D-5 -