2001-12-11_PERMIT FILE - C1981012A (2)

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_, `' COMMERCIAL TESTING & ENGINEERING CO. • -~ GENERAL OFf10 ES. ::! NORiN LA SALLE STREET. CNI(;AG O. RUN0~5 60601 AREA CODE Ott T36~E01 ~~ Reply to c• Instrumental Analysis Division Phone: 303-2789521 490 Orrhard Street December 3, 1980 Golden, CO 80401 ltr. Jack Gillespie 1,~:•,:_, i.:~,~~_ -~_, CF & I Steel Corporation iii%~'='-;~,1[j•;%~' „'; n. tl L. ~..~ P.O. Box 316 I ~ _ _ . I' . Pueblo, Colorado 81002 ~ -~':~' "- l~'' ;. ~; RE: IAD 97-F207-032-03 r1J'1~IAIG ~t oA.47~`/1 P.O. M26144 Release ;R26679 APJALYTICAL REPORT Three water samples were received for analyses on October 2, 1900. These samples were given our identification IAD X97-F207-032-03. - . All of the samples were analyzed for both dissolved (non-preserved in the field, then laboratory filtered ~vith a 0.45 um filter and then nitric acid preserved) and total (non-filtered and nitric acid preserved in the field), metals. Some discrepancies may be noted when comparing dissolved and total petals data. It should be kept in mind that as values approach she detection limit for any determination, the results may become inconclusive. This fact is based on instrumental conditions alone regardless of other analy- tical or sampling problems; i.e., contamination at the time of sampling, or contamination or loss during digestion, etc. The detection limit is defined as twice the standard deviation of the noise level. Results may be reported with 66`a confidence, by definition, at one standard deviation of the detection limit. In practical application, results approaching the detection limit are only good (at 959 confidence level) to plus or minus two (2) times the detection limit. Samples with deviations that are found to exceed this (betvreen totals and dissolved metals) are re?repared and reanalyzed in an attempt *_o eliminate analytical errors. If data still differs by more than twice the detection limit, problems other than analy- tical exist. Attention should then be directed to sampling and/or preser- vation procedures or other involved aspects. The same problems will arise if the detection limit is lowered by the use of alternative analytical methods. The same amount of material will exist in the sample, but the amount of deviation from that value is lowered. All samples for dissolved metals to be analyzed by atomic absor?tion ~•;ere first given a light acid digestion (to be sure 0.45 um filtered metals . - . are in solution). All samples to be analyzed for total metals by atomic - absorption were subjected to a rigorous digestion in hydrochloric and '_'•.;.,. nitric acids and, if there was sediment undissolved, filtered before •4A `~~` A \ . `~ • -- analysis. ~;', ., - .%,`N - ~.; uu wag. u, . u+.wen.... .c . c~u uuon. «v . u.++ao+e «v . cs[vn.no o~ ~ mnvu co. cos pen co ...e nor+,en. ... wren a • ~mou,eo eo +v