REV94461

• Permit No: C1981041
• IBM Index Class Name: Revision
• Doc Date: 3/7/1997
• Doc Name: ROADSIDE PORTALS PN C-81-041 TR MINE WATER POND 12
• From: DMG
• To: DAN MATHEWS
• Type & Sequence: TR22
• Media Type: D
• Archive: No

~~I ~I~~I~~~~~~~~~I~
999
STATE OF COLORADO
DIVISION OF MINERALS AND GEOLOGY
Depanmenl of Natural Resources
131 3 Sherman 51., Room 21 5
Denver, Colorado 80203
Phone: [phone]
FAX: (3071 B12-8106
DATE:
TO:
FROM:
RE:
March 7, 1997
Dan Mathews ~
Erica Crosby ~~
Roadside Portal Mine (C-81-041)
TR- ;Mine Water Pond #] 2
II~~~
DEPARTMENT OF
NATURAL
RESOURCES
Roy Romer
Governor
lames S Lochhead
Executive Dveaor
Michael 8. Long
Division Direcror
Dan, per your request I reviewed the technical Revision submitted by Powderhorn Coal Company
to add Mine Water Pond #12. I have [he following questions that should be addressed by the
operator;
1. Prior [o construction of Mine Water Pond #12, Powderhorn needs to obtain approval
from the Colorado Department of Health, Water Quality Control Division. The NPDES permit
needs to be revised to include Pond #12 as a mine water discharge point. The flocculant and
sulfuric acid to be added into the pond also need to be approved in the NPDES permit. Please
provide the Division with a copy of the revised NPDES permit to discharge mine water from
Pond #12, as well as approval of the flocculant and sulfuric acid to be used in the pond.
2. Please inform [he Division how Powderhorn will determine when and what quantity of
flocculant and sulfuric acid will be added to Pond #12.
3. Please inform the Division as to how Powderhorn predicted the amount of mine water
discharge leading into Pond #12. What is this number based on, and what will be done if more
inflow is encountered?
The SPCC needs to be updated to reference the sulfuric acid stored at the mine. Please
provide the Division with a copy of this plan.
5. On page 13-7, Powderhom states, " ... as an added precaution, the emergency spillway
dumps into Pond 5 which will allow additional settling capacity below the primary spillway of
Pond 5." The operator needs to demonstrate that Pond #5 will be able to store and/or treat the
additional mine water from Pond #12. The NPDES permit will also need to be revised to allow
mine water discharge and use of floculants in Pond #5. Please provide the Division with designs
demonstrating that sediment pond #5 can safely store or treat the mine water from Pond #12.