Laserfiche WebLink
ro <br />The United States Geological Survey (LTSGS) monitored the flow of the Middle Fork of the Purgatoire at <br />Stonewal( (07124050), approximately four miles upstream from the New Elk Mine, from May 1978 to <br />September 1981. The Purgatoire River at Madrid (07124200), approximately 15 miles downstream of the <br />Golden Eagle Mine, has been monitored since 1972. The size of the drainage area above the Stonewall station <br />is 52.1 square miles (mi2). There are some diversions for ircigation above the station. Recorded dischazges <br />during the three-and-a-half year period ranged from 2.8 cfs to 522 cfs (USGS, Water Resources Division, <br />1982). The size of the drainage area above the Madrid station is 505 miZ. There are diversions for ircigation <br />for about 6,000 acres upstream of the Madrid station. The average annual discharge between 1972 and 1995 at <br />Madrid was 71.4 cfs and the average annual runoff was 51,740 ac ft (Crowfoot et al, 1996). The annual runoff <br />in the Purgatoire is dominated by snowmelt, with peak flows occurcing in May and June. Summer and fall <br />thunderstorms generally produce smaller peaks of short duration. <br />1.2 MONITORING PROGRAM <br />Monitoring programs have been conducted since February 1984 to assess the effects of past, present, and <br />future mining operations on surface and groundwater quality and quantiTy. These programs provide <br />information to Basin and to regulatory agencies such as the Colorado Division of Minerals and Geology <br />(CDMG). CDMG programs are designed to monitor past and present, and to anticipate future, effects of <br />mining and reclamation activities on the hydrologic regime of the area. <br />The monitoring program has undergone several revisions. The revisions have resulted from data review by <br />Basin and CDMG. The monitoring program of springs and seeps is presented in Appendix B. As a result of <br />site reclamation and Phase II bond release, the monitoring program was reduced (Technical Revision 53) to <br />those stations and parameters presented in Tables 1.2-1 and 1.2-2. <br />The following are descriptions of the current sampling stations, their locations, and their purpose. These <br />stations are shown in Maps 7A and 7B, Regional Hydrology (see Permit Document). <br />Springs and Seeps <br />The spring and seep monitoring program samples field parameters on springs within a 2 r/s mile radius of the <br />underground workings once annually during the late summer of the year, to ensure that geohydrologic changes <br />associated with the mine do not diminish the water quantity or quality of springs. Fourteen springs are included <br />in the monitoring program (see Appendix B). <br />Surface Water (streams and rivers) <br />Alt surface water stations have been eliminated from the monitoring program <br />292-2002 AH Report (Mar.03.03)_rev2 4 <br />