HYDRO30347

• Permit No: C1981013
• IBM Index Class Name: Hydrology
• Doc Name: COAL INSPECTION REPORT
• Permit Index Doc Type: OTHER SURFACE WATER
• Media Type: D
• Archive: No

The mine recently encountered a significant source of ground water while driving
development entries at the Golden Eagle Mine. The water quickly began flowing in
the workings at a rate of several hundred gallons per minute and flooded a small
section of the underground workings. Operations in this area had to shut down until
the water could be pooped out. The source of the water is still being investigated
but appears to be a fault in communication with a large sandstone unit and/or the
Purgatore River. The operator met with MLRD in January, 1967 to discuss the issue
and an agreement was reached which would allow the operator to pump this water to
the sediment ponds on a short term basis and to the mine discharge ponds on a long
term basis. MLRD was not initially informed that the operator intended to use a
chemical additive to this mine water in order to aid in removing suspended solids.
The approved permit does not include the use of a chemical treatment system.
On March 10, 1988 we were informed in a letter that the operator had been adding a
chemical flocculant for several months. Nalco Coagulant No. 8873 had been used but
recently it was said that the operator changed to Nalco Coagulant No. 8852. The
safety sheets on the product indicated the following Toxicology Information:
Acute Oral Toxicity: LD50 = 4,699 mg/kg
Acute Dermal Toxicity: LD50 = 2,000 mg/kg
Skin Irritation: Mildly Irritating
96 hour LC50 (Bluegill Sunfish) with a 95$ confidence limit = 0.8 - 1.1 ppm
96 hour LC50 (Rainbow Trout) with a 95g confidence limit = 0.41-5.5 ppm
96 hour no effect concentration (Trout) = 0.18 ppm
While the material is noted as being harmful to fish (presumably affecting the
gills) the product is USEPA approved for use as a coagulation aid in treatment of
drinking water in doses up to 50 ppm. As the mine is in close proximity to a
perennial stream with a diverse aquatic community and there are alluvial wells used
by the public downstream, failure to obtain approval to use the chemical treatment
system represents a very serious situation.
The operator was negligent in not informing the Division about the mine water
treatment problem and in not seeking approval prior to its use. However, the
seriousness of the mine inflow problems and the fact that some underground mining
had to be ceased due to flooded workings understandably contributed to the
operator's haste in changing the mine water treatmenrt system.
Inspection
Asa result of the report to the Division by Sandy Marek of the Dept. of Health on
3/8/88 of a fish kill in the Purgatore River below the Golden Eagle Mine, the
scheduled monthly inspection of the mine was moved forward to Friday, March 11, 1988
and combined with an examination of the river within and downstream of the mine
permit area.
Prior to beginning the actual inspection of the mine facilities, portions of the
Purgatorie River were examined at Weston, Colorado and between Weston and the Golden
Eagle Mine. During these examinations, live trout were seen in the river at Weston
which is situated approximately 3 1/2 miles downstream from the mine entrance;
numerous dead trout were seen in and along the river at points approximately two to
two and one-half miles downstream from the mine.