Laserfiche WebLink
.= ~ • • iii iiiiiiiiniiiiii <br />STATE OF COLORADO <br />DIVISION OF MINERALS AND GEOLOGY <br />Deparlmenl of Natural Resources <br />1313 Sherman 51., Room 215 <br />Dem-er, CO 80203 <br />{'hone: 1703) 866-356% <br />FAX. (303) 83[ 8106 <br />Date: September 27, 1993 <br />To: Steve Shuey <br />From: Kent Gorham '~ln~' <br />Re: RN-02, Minor Revision Application, Hydrology Responses <br />pF Cp~O <br />~6A <br />Nc ~~ <br />" ~, <br />r <br />~ ~B)6 ~ <br />Roy Romer <br />Governor <br />nnichael B. Long <br />Division Direcbr <br />Surface water monitoring discharge (flow) measurements utilize a known culvert size, <br />flow depth and velocity determined by floating an object a known distance. Is this <br />technique at all surface stations or at a few? I would not recommend this technique <br />where it is necessary to have accurate discharge measurements. Where possible, a <br />Parshall flume should be used. <br />2. The operator does not indicate that each groundwater well is bailed or evacuated prior <br />to sampling. This technique should be standard practice for each well prior to sampling. <br />The operator was asked to clarify how metals on their currently approved sample <br />parameter list would be analyzed (i.e., dissolved, total, total recoverablel. The operator <br />took this opportunity to "shorten" their list, thereby dropping many parameters. My <br />comments are as follows: <br />a- Surface water iron needs to be total and dissolved. <br />b) Surface water manganese should be total, not dissolved. <br />c) Groundwater manganese should also include total manganese. <br />d) The operator seems confused for the reason that water samples are <br />tested for particular parameters. He gives the lack of a particular <br />parameter in the baseline sample as justification for not including it in <br />future sampling analysis. Sampling is done to ensure that particular <br />constituents do not "show up" in a concentration that is anomalously <br />high compared to previous samples. I agree that the sample list and <br />potentially their monitoring plan needs an overhaul, but due to the lack <br />of consistent AHR review in the recent past and sketchy or questionable <br />permit information, it is outside the context of this revision to address <br />the overall monitoring plan, <br />I would recommend that, if other questions are answered adequately, this minor revision be <br />approved with the condition that the operator submit within 90 days a technical revision to <br />