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In TRIM
<br />COLORADO DEPARTMENT OF PUBLIC HEALTH AND ENVIRONMENT, Water Quality Control Division
<br />Fact Sheet- Page 12, Permit No. C00000906
<br />VII. DISCUSSION OF NUMERIC EFFLUENT LIMITATIONS
<br />The following discussion applies to outfalls 001, 007, 008, and 010.
<br />A. Regulatory Basis for Limitations
<br />1. Technology Based Limitations
<br />a. Federal Effluent Limitation Guidelines - The federal guidelines that apply to outfalls 001, 007, 008, and
<br />010, are found under 40 CFR 434, titled Coal Mining, Point Source Category, Alkaline Drainage, Coal
<br />Preparation Plants and Coal Preparation Plant Associated Areas and Western Alkaline Coal Mining. The
<br />specific subparts currently applicable to these discharges follow, and applicable limitations are found in
<br />Table VII -1:
<br />Subpart B -Coal Preparation Plants and Associated Areas, which applies to "discharges from coal
<br />preparation plants and coal preparation plant associated areas..."(Outfalls 007 Et 008);
<br />Subpart D -Alkaline Mine Draining, which applies to "alkaline mine drainage from an active mining
<br />area resulting from the mining of coal...," (Outfalls 001 and 010); and
<br />Subpart F, which contains the alternate limitation provisions for precipitation events (Outfalls 001,
<br />007 Et 008).
<br />The federal guidelines applicable to outfalls 004, 011, and 012 (Subpart H) are discussed in Section VIII of
<br />this fact sheet.
<br />Table VII -1 - Federal Standards 40 CFR Part 434
<br />" These parameters subject to Burden of Proof Requirements see next section
<br />"* Best Available Technology - applies to best existing performance of treatment technology
<br />*" New Source Performance Standards - applies to a coal mine constructed after 5/4/84, or construction of a new shaft,
<br />slope, or drift.
<br />i. Alternate Limitation Burden of Proof Requirements: In conformance with 40 CFR 434.63, the
<br />permittee has the burden of proof when requesting relief from total suspended solids (TSS), total
<br />iron and/or settleable solids limitations, as appropriate. Relief shall be granted only when
<br />necessary and shall not be granted when the permittee has control over the discharge. The
<br />permittee should endeavor to meet the primary limitations whenever possible. Relief is not
<br />available for mine drainage from underground workings of underground mines that are not
<br />commingled with discharges eligible for alternate limitations (i.e., surface runoff). This is the case
<br />for outfall 001. In addition, relief is not available for mine drainage that is not subject to a
<br />treatment system/facility prior to discharge as contemplated in the US EPA Development Document
<br />for Effluent Limitations Guidelines and Standards for the Coal Minine Point Source Cateeorv.
<br />October 1982; i.e., relief is not available to outfall 010. Thus, the alternate limitations apply to
<br />outfalls 007 and 008 only.
<br />For rainfall, to waive TSS and total iron limitations, it is necessary to prove that the discharge
<br />occurred during the precipitation event, or within 48 hours after measurable precipitation has
<br />Limitations
<br />Parameter
<br />30 Day Avg
<br />Concentration
<br />Daily Max. Concentration
<br />pH, s.u. (minimum - maximum)
<br />6.0-9.0
<br />Total Suspended Solids, mg/l *
<br />35
<br />70
<br />Total Iron, mg/I.
<br />BAT**
<br />3.5
<br />7.0
<br />NSPS***
<br />3.0
<br />6.0
<br />Settleable Solids, ml/[*
<br />N/A
<br />0.5
<br />" These parameters subject to Burden of Proof Requirements see next section
<br />"* Best Available Technology - applies to best existing performance of treatment technology
<br />*" New Source Performance Standards - applies to a coal mine constructed after 5/4/84, or construction of a new shaft,
<br />slope, or drift.
<br />i. Alternate Limitation Burden of Proof Requirements: In conformance with 40 CFR 434.63, the
<br />permittee has the burden of proof when requesting relief from total suspended solids (TSS), total
<br />iron and/or settleable solids limitations, as appropriate. Relief shall be granted only when
<br />necessary and shall not be granted when the permittee has control over the discharge. The
<br />permittee should endeavor to meet the primary limitations whenever possible. Relief is not
<br />available for mine drainage from underground workings of underground mines that are not
<br />commingled with discharges eligible for alternate limitations (i.e., surface runoff). This is the case
<br />for outfall 001. In addition, relief is not available for mine drainage that is not subject to a
<br />treatment system/facility prior to discharge as contemplated in the US EPA Development Document
<br />for Effluent Limitations Guidelines and Standards for the Coal Minine Point Source Cateeorv.
<br />October 1982; i.e., relief is not available to outfall 010. Thus, the alternate limitations apply to
<br />outfalls 007 and 008 only.
<br />For rainfall, to waive TSS and total iron limitations, it is necessary to prove that the discharge
<br />occurred during the precipitation event, or within 48 hours after measurable precipitation has
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