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i <br /> I <br /> i <br /> 2. ASBESTOS SAMPLING PROCEDURE <br /> I <br /> Sampling procedures followed the National Institute for Occupational Safety and Health <br /> (NIOSH) ASBESTOS by TEM: METHOD. 7402 (reference method, Appendix A of the Air <br /> Monitoring Plan). Each sampling station consisted of a sampling pump (with a built-in <br /> rotameter), filter cassette, connective tubing, mounting materials, and a flag (Figure 3). The <br /> filters used in this procedure had 0.45 micrometers (µm) mixed cellulose ester membranes, <br /> 25 millimeter diameters, and were encased in conductive cassettes. The sampling pumps used in <br /> this procedure were GilAir-5 Constant Flow Air Sampling Pumps with a flow capacity of 1 to 5 <br /> liters per minute (L/min). The built-in calibrators on the GilAir-5 pumps were not accurate <br /> enough for sampling requirements. Therefore a bubble meter calibrator was used to determine <br /> calibrated values for each pump. The calibrator could then offer a "real" pretest value and <br /> provide a basis for determining a "calibrated" value on each individual pump rotameter. As <br /> directed in the reference method and assuming an insignificant amount of non-asbestos dust, <br /> each pump was calibrated to a volumetric air flow rate of 2 L/min before the sampling period. <br /> Sampling was conducted on July 26, 2007 and completed within one day. The field notes/data <br /> are presented in Appendix B. Sampling was performed during normal weather and operating <br /> conditions. A statement verifying normal operations is presented in Appendix C. During the <br /> eight-hour sampling period, Shaw personnel visually checked the sampling pumps on an hourly <br /> basis for fluctuations in the flow rate and corrected and recorded any deviations of more than <br /> 5 percent from the initial value. After sampling was completed, each pump was retested with the <br /> calibrator to find a "real post-test value. Ideally this value would have been the same as the <br /> pretest value of 2 L/min, but results were as low as 1.8 L/min. The pretest and post-test values <br /> were averaged over the total sample time, and the average value was used to calculate a total <br /> volume for each sample cassette. <br /> All samples were packaged, sealed, labeled, and stored in secured locations per the reference <br /> method. The samples were then shipped to the approved analytical laboratory within 24 hours. <br /> N:\UsersUobn WeberTor%wd IandfilMsbestoaMbestos Report Final.doc Rev.0,10/2/07 <br /> 119185 2 <br />