ARCHIVED REPORTS XR0012566 - Laserfiche WebLink

Home Browse Search

c I KLEINFELDER measure total ionizable compounds in parts per million by volume (ppmv) relative to a - calibration standard. Each sample was screened in the field,and the OVA readings were recorded on the boring log. OVA readings ranged from 0 to greater than 1000 ppmv. The highest readings were encountered in boring 13-10/MW-1 near the ground hater surface. A summary of the OVA readings is presented in Table 1. Based on the OVA readings, soil lithology, and depth in the borehole, soil samples 67511 z.nd 67521, collected at 31 feet from B-10 and B-11, -- respectively, were selected for quantitative analysis of purgeable TPH and BTEX. Additionally, three soil samples 67510, 67519, and 67535 were submitted for permeability - anaIysis by Yourgdahl and Asso-ciates, in El Dorado Hills,California. For the protection of the field crew, the OVA was also used to ;Measure the total ionizable concentration in the breathing zone prior to and during the drilling of the borings. No corsistent readings were notee in the breathing zone while drilling borings B-10 through B-12. High OVA readings 1-rere measured directly over the boring; however, windy conditions quickly dissipated the volatile organics away from the breathing zone. 3.3 I11Ci.',,TORING WELL INSTALLATION , Upon completion of the drilling, soil borings B-10 through B-12 were converted into monitoring wells MW-1 through MW-3, respectively (Plates 2 and 3). Table 2 summarizes the monitoring well construction details for the three monitoring wells which are also illustrated in the boring logs (Appendix A). Installation and construction details, and decontamination procedures are presented in Kleinfelder's field procedures (Appendix B). 3.4 MONITORING WELL DEVELOPMENT AND SAMPLING 'On February 21, 1991, the three monitoring wells (MW-1, MW-2, and MW-3) were developed to remove sediment laden water from the well, set the filter pack, and increase the effective hydraulic radius of the well. The well development and sampling procedures are explained in Appendix B, Kleinfelder Field Procedures. The well development Purge Characterization Logs are contained in Appendix D. After the monitoring wells were developed, they were allowed to equilibriate for approximately 48 hours. On February 21, 1991, monitoring wells MW-1, MW-2,and MW-3 F18.91-62 5 Copyright 1991 Kleinfelder, Inc.