HYDRO25324

• Permit No: M1988112
• IBM Index Class Name: Hydrology
• Doc Date: 12/22/2000
• Doc Name: MEMO NOTICE OF ISSUANCE OF THE PERMIT FOR BATTLE MTN GOLD CO-0045675
• From: CDPHE
• To: ATTENDEES AT THE PUBLIC MEETING ON THE BATTLE MTN PERMIT CO-0045675
• Media Type: D
• Archive: No

Page 1
COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division
Rationale -Page 17 Pertnlt No. CO-0045675
discharge point 002 will be submitted separately !rom the monthly DMR reports (or discharge point 001.
Results obtained from the monitoring conducted (or discharge point 002 will be presented in the quarterly BMP
report. This report will be due by the 28'" day of the month following the end of the calendar quarter.
For purposes of the Colorado Discharge Permit System, the permittee will be required to submit
documentation regarding any significant changes to the above descnbed system, as well as the monitoring
data as descnbed previously.
VI. TERMS AND CONDITIONS OF PERMIT
A. Determinatlon of ERluent Llmliatlons (Cont.)
3. Calculation o(Water Quality Based Effluent Limitations: Amass balance equation was used to determine the
effluent limitations that would not violate the allowable in-stream concentrations defined by the water quality
standards (except in the case of pH, where the limitations are set directly from stream standards or effluent
regulations without using a mass balance approach). The mass balance equation is:
M,Q,- M,Q,
M~ _
Q=
Where:
Q, = Upstream low flow (1E3 or 30E3) from Part III.B.2
Q= = Average daily effluent flow (design capacity)
Q, = Combined downstream flow (Q, + Q~
M, = Upstream background pollutant concentretion from 111.8.1 and Table VI-3
M: = Unknown; Maximum allowable effluent pollutant concentration
M, = Maximum downstream allowable pollutant concentration (stream standard or antidegradation-
based
standard)
Because o/the mathematical relationship between flow, pollutant concentration and pollutant mass,
concentretion limitations calculated using this method implicitly limit instream pollutant mass to the maximum
allowable level. Also, only flow and concentration limitations need to be specked in the pennrt. Mass
limRations are not required. A summary of the mass balance calculations is shown and discussed in Section
VI.A.4, as well as in Table VI-3.
4. Discussion of Effluent Limitations
a) eggulations for Effluent Limitations: The Regulations for Effluent Limitations (Regulation No. 62), apply to the
conventional pollutants. For this facility, the limitations for Total Suspended Solids and Oil & Grease are
based on this regulation.
b) Federal Effluent Guidelines and Standards: Federal guidelines that are applicable for the Copper, Lead, Zinc,
Gold, Silver, and MGybdenum Ores Subcategory of the Ore Mining and Dressing Point Source Category
are from 40 CFR Part 440.102 and 440.103. These federal technology-based effluent limitations
represent the tlegree of reduction attainable by the application of the best practicable control techndogy
currently available (BPT), and the application of the best available technology economically achievable
(BAT), respectively. However, these federal technokx,/y-based effluent limitations are only applicable for
active mining facilities.
Under the Federal definition, as descnbed in 40 CFR 440.132, an Active mining area- is a place where
work or other activity related to the extraction, removal, or recovery o(metal ore is being conducted,
except, with respect to surface mines, any area of land on or in which grading has been completed to
return the earth to desired contour and reGamation work has begun. Reclamation work has been initiated
at the BMR/ San Luis Mine, and according to this definition, it is not considered to be an Active mining
area.
However, if should also be noted that the proposed metals limitations for this permit which have been