|
Letter to Bryce Romig -3- November 6 1995
<br /> Ground Water Monitoring Program
<br /> It is stated in the technical revision application that detection limits
<br /> and lab analysis will follow protocols identified in "EPA Test Methods for
<br /> Evaluating Solid Waste - Physical/Chemical Methods (SW-846) ". This is
<br /> acceptable to the Division with the understanding that analytical methods
<br /> selected have detection limits sLfficiently low to be protective of
<br /> potential beneficial ground water uses, which in all three affected basins
<br /> at the Climax Mine are surface water quality protection.
<br /> Tenmile Creek Valley
<br /> In the technical revision application, a ground water point of compliance
<br /> is proposed at monitoring well GWM #2 . This is acceptable to the
<br /> Division, however, your proposal that numeric protection levels for GWM
<br /> #2 be established as the Colorado Basic Ground Water Standards must be
<br /> reconsidered. It is the Division's view that when the existing or
<br /> potential beneficial use of ground water is to recharge surface water,
<br /> that a numeric protection level necessary to prevent the exceedance of
<br /> surface water quality standards should be established. An exception to
<br /> this view-point would occur, in accordance with the Mineral Rules and
<br /> Regulations, where ambient ground water quality exceeds values for
<br /> protection of existing and reasonably potential future uses of ground
<br /> water, but such is not the case at GWM #2. Numeric protection levels
<br /> equal to receiving stream standards for segment 13 of the Blue River Basin
<br /> would be established for the following parameters: CN-, Cl, SO4, As, Cd,
<br /> CrIII, CrVI, Cu, Fe, Pb, Mn, Hg, Ni, Se, Ag, and Zn. In addition, numeric
<br /> protection levels for Mo would be established based on ambient quality.
<br /> Please provide your proposal for a numeric protection level for Mo at GWM
<br /> #2 based on a statistical analysis of the available data.
<br /> The Division concurs with your proposal to monitor for pH, Total Dissolved
<br /> Solids, static water level, Cd, Cu, Fe, Pb, Mn, Mo, Zn, and CN-. In
<br /> addition, the samples should be analyzed for hardness, Cl, SO4, As, CrIII,
<br /> CrIV, Hg, Ni, Se, and Ag. If, after 4 sampling episodes, any of these
<br /> additional parameters prove to be undetectable, they could be dropped from
<br /> the list.
<br /> The Division further concurs with your proposal to report routine ground
<br /> water sampling results with the Annual Reclamation Report. Ground water
<br /> quality data should be presented with a correlative table of the
<br /> appropriate receiving stream standard for comparison. For hardness based
<br /> standards, hardness to be used in equations should be determined in
<br /> accordance with Water Quality Control Commission Regulations.
<br /> It is stated in your proposed monitoring plan that if numeric protection
<br /> levels established for GWM #2 are exceeded, the well will be purged and
<br /> sampled again to verify the exceedance. It is further stated that in the
<br /> event of an exceedance, sampling frequency will be increased to quarterly,
<br /> and that the results will be reported to the Division upon analysis of
<br />
|