Laserfiche WebLink
i 1 <br /> CLEARWATER <br /> G R O U P <br /> Ertairanrrt crttai Scroices <br /> Before sampling, the wells were purged until water quality parameters had stabilized <br /> Stabilization occurred after approximately three wet casing volumes had been removed Prior to <br /> purging, the wells were checked for the presence of light non-aqueous-phase liquids (LNAPL), <br /> which were not detected in the wells Stabilization measurements of purged groundwater <br /> temperature, conductivity, and pH were made and recorded for each well prior to sample <br /> collection <br /> Following purging, each well was allowed to recharge to at least 80% of its static water level <br /> prior to sampling Groundwater samples were obtained from each well using disposable <br /> polyethylene bailers and decanted into clean laboratory supplied bottles Samples were labeled, <br /> documented on a chain-of-custody form, and placed on ice in a cooler for transport to the project <br /> laboratory Groundwater samples were analyzed by Kiff Analytical Labs, located in Davis <br /> California, a California State-certified laboratory, for concentrations of TPHg, BTEX and MTBE <br /> by EPA Method 8260B All field work was conducted in accordance with Clearwater's <br /> Groundwater Monitoring and Sampling Field Procedures and Natural Attenuation Processes <br /> and Recommended Monitoring Guidelines included in this report as Appendix A <br /> Dissolved Oxygen, ORP, Total and Ferrous Iron Field Testing <br /> Following well purging, Clearwater monitored dissolved oxygen (DO), and oxidation-reduction <br /> potential (ORP) using pre-cleaned down-well probes, and collected water samples for in-the- <br /> field iron testing (total iron, and ferrous iron) using portable iron test kits Dissolved oxygen <br /> concentrations ranged from 0 1 mg/L in MW-2 to 15 mg/L in MW-8 Oxidation-reduction <br /> potential ranged from —8 millivolts in MW-8 to 20 millivolts in MW-3 Total iron <br /> concentrations ranged from 0 0 mg/L to 13 mg/L in MW-4 and MW-7 Ferrous iron (Fe+2) is <br /> in the "reduced" state, and ranged from 0 0 mg/L in MW-2 to 1 1 mg/L in MW-5B Refer to <br /> Table 4 for the DO, ORP, Total iron, and ferrous iron data <br /> ZB178C/3rdQtr 2004 Monitoring Rpt 5 October 8,2004 <br />