2008-09-15_PERMIT FILE - C1992081

• Permit No: C1992081
• IBM Index Class Name: Permit File
• Doc Date: 9/15/2008
• Doc Name: CDPS Permit
• Section_Exhibit Name: Tab 13 Appendix 13-1
• Media Type: D
• Archive: No

COLORADO DEPARTMENT OF PUBLIC HEALTHAND ENVIRONMENT, Water Quality Control Division
Rationale, Page 3, COG-0850000 Coal Mining General Permit
Table Ill-2a: Effluent Limitations and Monitoring Requirements -Alkaline Drainage, Coal Preparation Plants and Coal
Preparation Plant Associated Areas and Western Alkaline Coalll~Iining (additional requirements apply to Western
Coal Mining, See Section III.A.3 of this rationale)
Limitations
Parameter 30-Day 7-Day Daily Rationale Monitoring Sample
Avg. Avg. Max. Frequency Type
______________________________________General Permit Requirements----_~_____________________________~_
Flow, MGD Report NA Report Discharge Evaluation Continuous / a
Instantaneous
pH, s.u. N/A NA 6.5-9.0 Water Quality Standards Weekly
Oil and Grease, mg/l N/A NA 10 State Effluent Regulations Weekly
___________________________~FederalEffluentLimitation Guidelin es---______________~_____ ~__w___
Total Suspended Solids, nig/! 3S NA 70 Federal ELG Weekly
Totallron, mg/1
Existing Sources (before 5/4/84) 3.S NA 7.0 Federal ELG Weekly
New Sources (after 5/4/84). 3.0 NA 6.0
Settleable Solids, n:l/1 Report NA 0.5 Federal ELG Weekly
______________________W_____ ______Site Specific Limitations-----__ ---_______w_______w________ _______~_
Total Dissolved Solids, mgR * Report NA Report Salinity Regulations Quarterly a
Total Phosphorus (as P), mg/1 ** Report NA Various Control Regulations Monthly
Total Recoverable Iron, ug/1 ***
Other Polliitants of Concern
Whole Effluent Toxicity (WET)
Chronic
Acute
1000 NA NA Water Quality Standards
Various NA Various Water Quality Standards
Stat Diff and IC2S > IWC State Permit Limitations
LCSO > 100% State Permit Limitations
Weekly
Weekly
Quarterly
Recorder /
In-situ a
Grab
Visual 3
Grab
Grab
Grab
Grab
Grab
Grab
Grab
3 Grab/Test
Grab
Footnotes 1-4, *, and **, See Footnotes under Table III-1
*** This limitation will apply and will substitute jor the 30-day average total iron limit based upon the ELG, when a total recoverable iron standard is applicable to the
stream segment.
Alternate Limitations For Alkaline Mine Drainage, Coal Preparation and Associated Areas and Western Alkaline Coal
Mining -Table III-2b contains limitations for any discharge or increase in the volume of a discharge from an above ound
alkaline mine (or an underground alkaline mine where the effluent is commingled with other categorical wastewater prior to
discharge), caused by precipitation within any 24-hour period less than or equal to the 10-year, 24-hoitr precipitation event
(or snowmelt of equivalent volume) may substitute the following limitations for these specific parameters only, subject to
burden of proof requirements described in Part I.B.4 of the permit.
Table III-2b: Alternate Effluent Limitations and Monitoring Requirements -Alkaline Drainage, Coal Preparation Plants and
Coal Preparation Plant Associated Areas and Western Alkaline Coal Mining (additional requirements apply to
Western Coal Mining, See Section III.A.3 of this rationale)
Limitations ., _
Parameter .. 30- 7-Day Dail
y Rationale Monitoriti
g Sam le
P
Day Avg. 'Max.
_, Frequency l TYPe
Avg
_______________~_____________FederalEffluentLimitation Guidelines---_______________ ______________
Total Suspended Solids, mg/! Report NA Report Federal ELG Weekly Grab
Totallron, mg/1
Existing Sources (before 5/4/84) Report NA Report Federal ELG Weekly Grab
New Sources (after 5/4/84) Report NA Report
Alternate Limitations For Alkaline Mine Drainage, Coal Preparation and Associated Areas, and Western Alkaline Coal
Mining -Table III-2c contains limitations for any discharge or increase in the volume of a discharge from an above ground
alkaline mine (or an underground alkaline mine where the efflicent is commingled with other categorical wastewater prior to
discharge), caused by precipitation within any 24-hour period greater than the 10-year, 24-hour precipitation event (or
snowmelt of equivalent volume) may substitute the following limitations for these specific parameters only, subject to burden
ofproof requirements described in Part I.B.4 of the permit.