2011-08-18_HYDROLOGY - M1977306

• Permit No: M1977306
• IBM Index Class Name: HYDROLOGY
• Doc Date: 8/18/2011
• Doc Name: Colorado Discharge Permit System
• From: Water Quality Control Division
• To: Cotter Corporation
• Email Name: GRM
• Media Type: D
• Archive: No

COLORADO DEPARTMENT OF PUBLIC HEALTH AND ENVIRONMENT, Water Quality Control Division
Rationale — Page 7, Permit No. C00036251
definition of process water and storm water at non -coal mining sites (02/15/1993) that was
developed for the purpose of defining what sources are subject to Federal effluent limitation
guidelines. This determination has been made consistent with that Division policy.
All Federal Effluent Limitation Guidelines (ELG) under 40 CFR 440.32, titled Ore Mining and
Dressing Point Source Category; Subpart C — Uranium, Radium and Vanadium Ores
subcategory, and all applicable State standards, have been applied to as effective immediately.
Consistent with the requirements of the Clean Water Act and 40 CFR 125.3, compliance
schedules are not allowed for effluent limits based on technology based standards established in
accordance with Federal requirements. In the 1970s and 1980s, EPA provided some opportunity
for additional time to come into compliance with these types of effluent limitations, but now the
compliance deadlines have passed.
The limitations that apply are found in Table VI -1.
Table VI-1 — Federal Standards (40 CFR 440.32 & 33). (All limitations are expressed as mg/1
unless otherwise specified)
Limitations
Parameter 30 -Day Avg. Concentration Daily Max. Concentration
Total Suspended Solids 20 30
Dissolved Radium -226 pCi /1 3 10
Total Radium -226 pCl/1 10 30
Total Uranium 2 4
COD 100 200
Total Zinc 0.5 1.0
pH, s.u. 6.0 to 9.0
i. Total Suspended Solids - The TSS concentrations from the Federal standards above are the
most stringent effluent limits and are therefore applied. These limitations are the same as those
contained in the previous permit and are imposed effective immediately, for Outfalls 001A,
OO1B, 002A, and 002B.
ii. Dissolved Radium -226 — A Federal ELG exists for dissolved radium 226. The limitations
are 3 pCi /l for 30 -day average and 10 pCi/1 for daily maximum. These limitations are the same
as those contained in the previous permit and are imposed effective immediately, for Outfalls
OO1A, OO1B, 002A, 002B and 002C.
iii. Total Radium -226 - A Federal ELG exists for total radium 226. The limitations are 10 pCi /1,
for 30 -day average and 30 pCi /1 for daily maximum. These limitations are the same as those
contained in the previous permit and are imposed effective immediately, for Outfalls 001A,
OO1B, 002A, 002B and 002C.
iv. Total Uranium - The RP analysis discussed below resulted in no RP for outfall 002A,
however, the Federal ELG limits of 2000/40001.1g/1 for 30 -day average /daily maximum for total