2008-12-18_REPORT - C1982056 - Laserfiche WebLink

Home Browse Search

Requiie- Requirement Requirement ment complied Comment citation with ? (yes / no) The mine discharges surface runoff and pumped mine water to the following stream segments in Region 12 of the Yampa River basin: Segment 13c, Trout Creek above Fish Creek Segment 13b, Foidel Creek Segment 13a, Trout Creek below Fish Creek CWQCC lists numeric standards for the segments in its regulation 3.7.0. Historical E. Instream CWQCC regulation monitoring data from the stream segments indicate the iron numeric standard is frequently Numeric 3 3 0 yes exceeded and the lead and manganese standards are occasionally exceeded. Premining Standards . . data indicate these exceedances are probably unrelated to mining. Monitoring data in the AHR indicate the mine's discharges did not cause exceedances of instream standards in the stream segments. Table 48 of the report indicates that in March 2007 the 250 mg/1 sulfate standard was exceeded on lower Trout Creek at site 1005, but data from Sites 305 (Fish Creek), 900 (Foidel Creek), and 301 (Trout Creek) indicate the exceedance was not caused by the mine. The Wadge overburden and the Twentymile Sandstone are the two aquifers most likely to be affected by mining. If the workings are developed to the maximum extent approved, the F. Basic Standards monitoring locations of both formations will be upgradient from mine workings. The (Interim CWQC regulation following wells serve as the Foidel Creek Mine's ground water points of compliance: Narrative .6 41.S.C yes 97013TM (Twentymile sandstone), 008-77-58 (Wadge overburden), 008-AU3 (Fish Creek Standard) for alluvium), and 008-AT-1 (Trout Creek alluvium). The mine's annual hydrology reports Ground Water contain long-term data from these wells. These data show the Foidel Creek mine is in compliance with the Basic Standards for Ground Water at the ground water points of compliance. All sampling frequencies were met, with the exception of the July quality sample for Trout Creek sites 301, 69, and 1005. Page 11 of the 2007 report explains that these samples G. Sampling Exhibit 14 of were collected, but the operator submitted the wrong parameter list to the lab. The frequency at CDRMS mining See operator's representative explained by phone that closer attention will be given in the surface water permit C-82-056 comment future to the summer Trout Creek lab analysis schedule which differs from the schedule monitoring sites for all other streams. Missing the July quality samples at these three sites in 2007 (and in 2006) does not impair the Division's ability to verify compliance because data are available from June and August. H. Parameters to be Exhibit 14 of See sampled at surface water CDRMS mining comment sites permit C-82-056 on G Page 2