Abandoned and Inactive Mines
The data below represent everything available in the MBMG Abandoned and Inactive Mines (AIM) database.
| AIM Id | Name | Alternate Name | District | County |
|---|---|---|---|---|
| PK008467 | MCLAREN TAILINGS | COOKE CITY | PARK |
| MRDS | AMLI | MILS | Latitude | Longitude | Datum |
|---|---|---|---|---|---|
| 34-004 | 45.0214 | -109.9236 |
| Township | Range | Section | QSection | UTM Northing | UTM Easting | UTM Zone | UTM Datum |
|---|---|---|---|---|---|---|---|
| 09S | 14E | 25 | ADCA |
| Average Elevation | Elev Units | Land Owner | 250K Quad | 100K Quad | 24K Quad |
|---|---|---|---|---|---|
| 7670 | F | BILLINGS | RED LODGE | COOKE CITY |
| Property Type | Update Date | Who Updated |
|---|---|---|
| MILL | 12/16/1997 | MDK |
| Information |
|---|
|
Agency: NF Region District: R1 Ranger District: GARDINER Forest Service Tract: Watershed Code: 10070001 Forest or Resource Area: GALLATIN Owner: M Impact: Report: The McLaren tailings are considered to be a part of the New World mining district and plot on the Cooke City 7.5-min. quadrangle. Some Cooke City residences are within 1,000 ft of the site and most of the population of Cooke City lives within ¾-mi of the tailings. The site is easily accessible by vehicle and by hiking; it is within 500 ft south of Highway 212. The tailings are found on the Cooke City 7.5-min. quadrangle in ADCA sec. 25, T09S, R14E at an elevation of 7,640 to 7,680 ft. They are primarily on private land but extend onto GNF-administered land. GCM Services Inc. (Gray, 1998) conducted a historical study of the Republic Mill and the Cooke City area in general for the Montana Department of Environmental Quality in 1998. They summarized some of the history and origin of the McLaren tailings. The McLaren Gold Mines Company processed ore from the New Year's Gift Mine at the site east of Cooke City beginning in 1934. After a brief period of control from 1938 to 1940 by Newmont Mining Corporation, McLaren again produced metals from the McLaren properties until 1953. The last time the tailings dam failed was in 1950; it was reinforced in 1990 (Montana Standard, August 13, 2000). Recorded production included 60,000 oz gold, 17,000 oz silver, and 4 million lb copper from the McLaren mine and mill. Production of the McLaren Gold Mines Company came between the years of 1940 and 1952, with the peak year being 1949 when it processed 39,139 tons of ore. One mill burned down October 28, 1942 (Parsons and others, 1962?). Another mill was closed and the equipment was liquidated in 1953. The mill processed ore by flotation. Ore minerals (in order of their magnitude) included pyrite, chalcopyrite, covellite, bornite, and chalcocite. Chalcopyrite was of primary importance (Griswold, 1947) with non-ore minerals consisting of copper oxides, native copper, and iron oxides (including magnetite). Gangue materials included monzonite, siliceous limestone, and quartz.Although the area has been partially reclaimed there are still concerns as to the stability of the impoundment. One upstream water sample (SMTS10H) on GNF-administered land and one downstream (SMTS20H), taken within the floodplain, were collected at the site on 08/25/99. The first sample was taken upstream from any recognizable tailings and the downstream sample was taken approximately 50 ft upstream from the confluence of Miller Creek with Soda Butte Creek. More samples were not collected because of the private land position. No soil samples were taken because of the private land position. Pioneer Technical Services (1995) reported on the soil analyses at this site. They found that arsenic, copper, cadmium, and iron in the waste rock were at least three times background. Tailings had elevated levels of cadmium, iron, copper, and mercury. They estimated the volume of tailings at 370,000 cubic yards and waste at 8,000 cubic yards. The flow at the upstream site was approximately 1 cfs (448 gpm). The bed was slightly iron stained. The pH upstream of the tailings was 7.62 and the SC was 239 mhos. Downstream of the tailings, the pH was 7.67 and the SC was 312 mhos. The creek bed was bright orange, extremely iron stained at the downstream site. Most of the streambed up to the highwater mark was coated with iron oxides. The flow at the downstream site was 1.25 cfs or 561 gpm. The only exceedence was in manganese which exceeded the secondary MCL. Pioneer Technical Services (1995) noted an observed release of iron in Soda Butte Creek, but the downstream sample did not exceed any MCL's at that time. Sparse to moderate vegetation, mostly grasses, grew on the reclaimed tailings. The edges of some of the waste were eroding and, so, were not vegetated. The trees growing along the banks of Soda Butte Creek appeared healthy. The McLaren tailings have been, and continue to be, a visible source of concern considering their close proximity to Soda Butte Creek and Yellowstone National Park. They were stabilized and recontoured after the fires of 1988 (Metesh and others, 1999), some question exists of their long-term stability. They do not, however, appear to presently contribute a large amount of metals to Soda Butte Creek. No structures remained at this site. The original mill has been destroyed. The tailings on GNF-administered land showed evidence of being actively eroded. They had rills and deep gullies on the east side of the site. These could be hazardous to ATV's or other vehicles. Safety may be an issue because of the close proximity of these tailings to Cooke City. There was evidence of recreational use. |
| Sample Id | Sampler | pH | SC | Date | TempC | Flow Rate | Flow Units | Flow Method | Source | Ind No | Veg | Stain | Salt | Sulf | Turb | Location Related to Stream | Stream | Sedimention | Photos Available? | Photo Numbers | Remarks |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| SMTS10H | PAH | 7.62 | 239 | 8/25/1999 | 9 | 1 | CFS | EST | STREAM | NO | N | Y | N | N | UP | SODA BUTTE CREEK | SLIGHT | Y | 78-15 | UPSTREAM OF MCLAREN TAILINGS | |
| SMTS20H | PAH | 7.67 | 312 | 8/25/1999 | 10.4 | 1.25 | CFS | ESTIMATED | STREAM | ST | Y | Y | Y | DOWN | SODA BUTTE CREEK | SLIGHT | Y | 78-18 | CLOUDY WITH IRON PRECIPITATE ON STREAM BED |
| Information |
|---|
|
Mill Tailings: Y Adit Discharge: N Metal Leaching: Y Water Erosion: Y Residence: Y Hazardous Materials: N Open Adit: N Visit: Y Comments: PART OF NEW WORLD MINING DISTRICT RESPONSE AND RESTORATION PROJECT |
End of report. Retrieved 5/4/2024 9:18:51 PM.
The preceding materials represent the contents of the databases at the Montana Bureau of Mines and Geology at the time and date of the retrieval. The information is considered unpublished and is subject to correction and review on a daily basis. The Bureau warrants the accurate transmission of the data to the original end user at the time and date of the retrieval. Retransmission of the data to other users is discouraged and the Bureau claims no responsibility if the material is retransmitted. There may be data in the request area that are not recorded at the Bureau.