1988-04-11_PERMIT FILE - C1981008A (21)

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Surface Water Quality Sample Handling, Preservation, and Analysis Surface water quality samples are collected by grab sampling or using a depth integrated sampler. Table 15-4 indicates the sample type, preservative, and bottle type necessary for analysis of the particular constituents shown. Raw and/or raw acidified water samples are taken from the sampling site and placed into specially prepared sample bottles. Portions of the raw samples to be field-filtered are forced through a 0.45 micron membrane using a skougstad type plastic barrel filter. The water samples are chilled by packing in ice and taken as rapidly as possible to Peabody's present contract laboratory (ACZ Laboratories, Steamboat Springs, Colorado). Laboratory procedures are consistent with those outlined in the U.S. Environmental Protection Agency's Manual Methods for Chemical Analysis of Water and Wastes (1983). All surface water samples are field tested for pH, temperature, and conductivity at the time they are collected. On an annual basis field equipment is tested for accuracy. The field equipment used for sampling conductivity, salinity and temperature at the Nucla Mine and the Nucla East mining area (YSI conductivity meter) was last tested for accuracy on December 10, 1987. The testing was performed by comparing the Nucla conductivity meter against an identical (previously calibrated) meter used for similar measurements at Peabody's Seneca Mine in northern Colorado. Both meters were used to measure the conductivity and temperature of tap water. The Seneca meter measured the water as 380 umhos at 10°C, while the Nucla meter registered readings of 360 umhos at 10°C. Temperature readings for both meters were identical, and the Nucla conductivity meter measured the conductivity of the water within 5.3 percent of the Seneca meter. The Seneca conductivity meter was calibrated on July 31, 1987. The calibration was performed by measuring the conductivity of a 0.01 demal potassium chloride (KC1) solution at 210C (YSI, 1979). Based on the conductivity table for this solution at 210C (YSI, 1979), the theoretical conductivity should be 1300 umhos. The Seneca meter registered a conductivity of 1300 umhos at 21°C for the prepared solution, which indicated accurate calibration of the Seneca conductivity meter. The pH meter used to measure field-determined pH values at the Nucla Mine and Nucla East mining area is calibrated by performing two point calibrations prior to each daily round of monitoring activities and one point calibration prior to each measurement using buffer solutions of known pH values obtained from outside laboratories. Three buffer solutions 15-7 Revised 04/11/88