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<br /> <br />by tl~e Colorado Department: oC Natural Resources (1984) and are listed in 'f'able <br />2. 'L'he Ilealth Department of the Colorado Department of Natural Resources was . <br />contacted and ttte ISS leave not changed since the F Seam adequacy responses were <br />submitted. In addition to the ISS, GPILRB leas stipulated t}iat water quality in <br />the Clorth Fork be protected against salinity increases such that the <br />conductivity is less than 0.7 millimhos and the SAR of North Forlc water be <br />maintained below 3. <br />Selected water quality data obtained by tl~e U.S. Geological Survey and <br />West Elk Coal Company (WECC) were reviewed to estimate the water quality of the <br />North Fork during low flow periods. Tlie data reviewed consisted of 15 sainpl.ing <br />events conducted by the USGS during the October 1981 - September 1982 water <br />year and quarterly sampling conducted by WECC. Data generate<i since subinit:tal <br />of t1~e F Seam Adequacy Responses is provided in Attaclunent 1. of this report. <br />AL1 data reviewed are summarized in Table 2. The lowesC flow volume in Clie <br />Nortl~ Fork normally occurs during the months of October t.hrougl~ February. <br />Water quality data obtained for the remaining months during, wliicl~ flow are <br />generally in excess of 10(1 cfs and were not reviewed Cor the purpose of this <br />analysis, nor are they pre<;ented in Table 2. , <br />LEACIIAT'E TESTING RESULTS <br />Leacliate tests were ccnducted on core chip samples from 6 drill Boles that <br />Y T <br />provide representative samples of B seam refuse materials. Drill hole ~'~~_ <br />~ r ~ <br />locations are shown in Figure 1. Core chips were taken from various elevations ~ ~ ~ QQ~' <br />along the length of bore hole Dll-3 corresponding to the different lithologies ~'~ Se C- <br />~. 4. a ~ v <br />present, for a total of 23 samples. Individual leachate tests were performed on h ~ ~ h~~. <br />each of these 23 samples wl~iclr represent the refuse generated by the access v-"~ ~ ~ •7 <br />slopes and ventilation shaft. 1'I~e tests were performed by ACZ, Inc., Laboratory ^ %', <br />Division, of Steamboat Springs, Colorado and tl~e results are provided in 1'1 <br />Attachment 2. Eleven composite samples from the roof and floor materials from <br />D11-3, SOM-40A, SOM-41, SOM-42, SOM-44 and SOM-C721{ were tested to represent the <br />roof and floor refuse, with tl~e results also provided in Atte~climent 2. "['lie <br />[ests were conducted by cr~rsl~ing tl~e core chip samples to the -~20 mesh si::e, <br />shaking for 30 minutes in distilled water in a one to five ratio by weight, ~~nd <br />4 <br />