Laserfiche WebLink
iii iiuiiiiiiiiiiii ~ ~. <br />STATE ~ COLORADO <br />MINED LAND RECLAMATION DIVISION of ~o<o <br />Depanmeni of Natural Resources ti`` ~ - '~ <br />NT3:r :I.~ 90 <br />1313 Sherman St., Room 215 ~ ` <~ , <br />Denver, CO 80203 ' • <br />303 866-3567 •. 6 <br />FAx 303 8328106 <br />Roy Romer, <br />Governor <br />DATE: December 23, 1991 Freo R. soma. <br />Division Drtecmr <br />T0: Susan Morrison ,(~ (~ <br />FROM: Margot Anderson `~~--\~n kll,t~~~ <br />RE: 1990 Annual Hydrologic t Review, <br />Edna Mine, File No. C-80-001 <br />I have reviewed the 1990 Annual Hydrologic Report prepared by the Pittsubrgh <br />and Midway Coal Mining Company for the Edna Mne. I have the following <br />comments: <br />1. The variations 1n the orthophosphate data plots are due to a <br />decimal placement error during transfer of data from raw lab <br />pages to plotting database. <br />2. The elevation of manganese for the September and October 1983 <br />groundwater sample data and a lesser increase for May through <br />July 1986 appear to be due to unusual mobilization of this <br />constituent on an occassional basis. There is a tentatively <br />identified trend 1n the increased levels from upstream to <br />downstream over both two-month periods. <br />3. The May 1984 spike in surface water sample data for manganese <br />appears to be a decimal placement error or the result of a lab <br />error. <br />4. High specific conductance levels for the October 1990 measurements <br />is believed to have resulted from a calibration or scale error of <br />the instrument used as it is present for all surface water samples <br />and there is no corresponding elevation of any other constituent or <br />total dissolved solids (TDS). <br />5. The higher levels of constituents for WR-1 are consistent with a <br />spoils monitoring site. <br />6. The sampling and analysis meets the requirements of Rule 4.05.13 <br />and of the monitoring plan. <br />7. The data falls within the historical ranges with the exception of <br />those mentioned above. <br />8. The data from the 1990 sampling and measurements are within the <br />projections of the Probable Hydrologic Consequences (PHC). <br />MA/eke <br />0233E <br />