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HomeMy WebLinkAboutWell Permit 0042757COLORADO 4210 East 11th Avenue Denver, Colorado 80220-3716 Phone (303) 320-8333 Telefax Numbers: Main Building/Denver (303) 322.9076 Ptarmigan Place/Denver (303) 320-1529 First National Bank Building/Denver (303) 355-6559 Grand Junction Office (303) 248-7198 Pueblo Office DEPARTMENT (719) 543-8441 OFAHEALTH ROY ROMER Governor JOEL KOHN Interim Executive Director April 23, 1992 R. E. Lawrence, Project Director P.O. Box 9136 Albuquerque, NM 87119 CERTIFIED MAIL NO: P 784 032 533 RE: Final Permit, Colorado Wastewater Discharge Permit System Number: CO— 0042757 - M -K FERGUSON COMPANY Gentlemen: Bproig,- i I/ ,9 MAY Q 1992 6F GAHFh LU OUN7-y Enclosed please find a copy of the permit which was issued under the Colorado Water Quality Control Act. Your discharge permit requires that specific actions be performed at designated times. You are legally obligated to comply with all terms and conditions of your permit. It is especially important to note the "EFFECTIVE DATE OF PERMIT", not the date signed, located in the lower right hand corner of page 1, of your permit. It is illegal to discharge per the conditions of this permit until that date. Please read the permit and if you have any questions contact this office at 331-4590. Sincerely, Robert J. Shukle, Chief Permits and Enforcement Section. Water Quality Control Division cc: Permits Section, Environmental Protection Agency Regional Council of Government Local County Health Department District Engineer, Field Support Section, WQCD Stan. May, Field Support Section, WQCD Ginny Torrez, Permits and Enforcement Section, WQCD Anne Ihlenfeldt, Permits and Enforcement Section, WQCD Permit Drafters, Permits and Enforcement Section, WQCD RJS/lg Enclosure pnutd o I rc:,cGd p yv • 6' COLORADO DEPARTMENT OF HEALTH Water Quality Control Division 4210 East llth Avenue Denver, Colorado 80220 SUMMARY OF RATIONALE M -K FERGUSON COMPANY URANIUM MILL TAILINGS REMEDIAL ACTION AT RIFLE ESTES DISPOSAL SITE PERMIT NUMBER: CO -0042757, GARFIELD COUNTY I. TYPE OF PERMIT: II. FACILITY INFORMATION: A. Facility Type and Fee Category: B. SIC Nos.: C. Legal Contact: D. Facility Contacts: CONTENTS TYPE FACILITY INFORMATION RECEIVING STREAM FACILITY DESCRIPTION PERFORMANCE HISTORY TERMS.AND CONDITIONS REFERENCES CHANGES FOLLOWING PUBLIC New PAGE 1 1 2 5 11 11 28 NOTICE 28 Category 3, Subcategory 8 - Hardrock Mining - Milling with Discharge from 50,000 gallons per day or greater - Current fee $3090/year per CRS 25-8-502 1629 - Reclamation Projects Construction 1094 - Former Uranium Mill (Tailings Disposal) Mr. R. E. Lawrence, Project Director P.O. Box 9136 2309 Renard Place, S.E., #300 Albuquerque, New Mexico 87119 (800)+443-4379 or (505)+766-3227 Randy Withee, Project Site Manager P.O. Box 151 24230 Highways 6 and 24 Rifle, CO 81650 (303)+625-4618 Sharon Arp U.S. Department of Energy P.O. Box 5400 5301 Central Avenue, N.E., Suite 1700 Albuquerque, New Mexico 87115 (505)+845-5668 COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 2. Permit No. C0-0042757 E. Facility Location: The Rifle Estes Gulch disposal site is located in the SW 1/4 of Sec. 14, T5S, R93W, approximately 5 miles north of Rifle on the State Highway 13, as shown in figures 1 and 2 of the permit. F. Discharge Points: G. Discharge Flows: III. RECEIVING STREAM: 001 - the effluent pipe from the wastewater treatment plant at the Rifle Estes Gulch Disposal Site, and prior to entering Estes Gulch, as shown in figures 1 and 3 of the permit. 002 - the emergency spillway structure from the retention'pond at the Rifle Estes Gulch Disposal Site, and prior to entering Estes Gulch, as shown in figures 1 and 3 of the permit. 001: 0.0864 MGD, or 60 gpm (portable wastewater treatment plant average design capacity) 1.95 MGD (1354 gpm; projected maximum daily flow) 002: 0.0283 MGD average flow during the ten months of projected discharge; 0 - 0.0488 MGD (projected monthly average flow range) 1.95 MCD (1354 gpm; projected maximum daily flow) A. Identification, Classification and Standards 1. Identification: The M -K Ferguson Rifle Estes Disposal Site outfalls will be discharging to Estes Gulch (segment 4), which goes to Government Creek, and then to the Colorado River (segment 1), Lower Colorado River Basin (Region 11). The distance from the discharges to the Colorado River is approximately 4 miles. 2. Classifications: Segment 4 is classified for the following existing uses: Recreation, Class 2; Aquatic Life, Class 2 (Cold); Agriculture. The downstream segment 1 is classified for the following existing uses: High Quality, Class 2; Recreation, Class 1; Aquatic Life, Class 1 (Cold); Agriculture; Water Supply. Numeric Standards: The complete list of standards which have been assigned in accordance with the above classification can be found in 3.7.0, Classifications and Numeric Standards for the Lower Colorado River Basin (5 CCR 1002-8), as amended February 4, 1991. The standards in segment 4 which have been reviewed with respect to this facility's discharge include those indicated on the next page. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 3. Permit No. C0-0042757 3. Numeric Standards: (Continued) Segment 4 (Estes Gulch and Government Physical and Biological pH Inorganic Boron Cyanide, free Metals Arsenic (acute) - 0.1 mg/1 Cadmium (chronic) - 0.01 mg/1 Chromium, tri (ch)- 0.1 mg/1 Chromium, hex (ch)- 0.1 mg/1 Copper (chronic) - 0.2 mg/1 Segment 1 (Colorado River): Physical and Biological pH Inorganic Ammonia (NH3), unionized Boron Chloride (C1) Cyanide, free Nitrate (NO3) Nitrite (NO2) Sulfate as SO4 Sulfide as H2S, undis. Metals Arsenic (acute) _ Cadmium (chronic) _ Cadmium (acute) _ Chromium, tri (ac) - Chromium, hex (ch)= Chromium, hex (ac) - Copper (chronic) - Copper (acute) Iron, total (ch) _ Iron, dis. (ch) Lead (chronic) Creek): - 6.5 - 9.0 s.u. - 0.75 mg/1 - 0.2 mg/1 Lead (chronic) - 0.1 mg/1 Nickel (chronic) - 0.2 mg/1 Selenium (chron) - 0.02 mg/1 Zinc (chronic) - 2.0 mg/1 - 6.5 - 9.0 s.u. - 0.02 0.75 - 250.0 0.005 10.0 = 0.05 = 250.0 0.002 mg/1 mg/1 mg/1 mg/1 mg/1 mg/1 mg/1 mg/1 0.05 mg/1 Lead (acute) = 0.05 mg/1 0.0022 mg/1* Manganese (tot) = 1.0 mg/1 0.0105 mg/1* Manganese (dis) - 0.05 mg/1 0.05 mg/1 Mercury (chr.) = 0.00001 mg/1 0.011 mg/1 Nickel (chronic) = 0.19 mg/1* 0.016 mg/1 Nickel (acute) = 1.8 mg/1* 0.025 mg/1* Selenium (acute) - 0.01 mg/1 0.040 mg/1* Silver (chronic) = 0.00034 mg/1* 1.0 mg/1 Silver (acute) = 0.0091 mg/1* 0.3 mg/1 Zinc (chronic) = 0.063 mg/1* 0.013 mg/1* Zinc (acute) = 0.22 mg/1* The calculated dissolved standards (indicated by * above) are based upon hardness dependent equations specified in 3.7.0, Classifications and Numeric Standards for the Lower Colorado River Basin (5 CCR 1002-8). A total hardness value of 239 mg/1 as CaCO3 was used, which is the mean of data from WQCD Station No. 000047, the Colorado River at New Castle. The actual data and calculations are in the permit file and are available upon request. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 4. Permit No. C0-0042757 B. Receiving Water Data 1. Stream Low Flow: The flows which will be used to calculate effluent limitations are acute flows, those that occur for one day every three years (1E3), or chronic, those that occur for thirty days every three years (30E3). The low flows for both Estes Gulch and Government Creek are based upon indications of intermittent flow in topographic maps, as well as visual assessments that there has been no water in these streams at certain times of the year. The flows have been determined by the Water Quality Control Division and are as follows: Type Flow Acute (1E3) 0.0 cfs (0.0 MGD) Chronic (30E3) 0.0 cfs (0.0 MGD) The low flows for the Colorado River at Rifle are the same as what were determined for the M -K Ferguson Company Rifle Processing Sites permit (Permit No. C0-0042552), which are as follows: Type Flow Acute (1E3) Chronic (30E3) • 1200 cfs (776 MGD) 1400 cfs (905 MGD) 2. Impacts on Downstream Water Supplies and Other Downstream Classified Uses: According to information in the permit application, no surface water is used at the Estes Gulch Disposal site, nor along Government Creek or Thirty-two Mile Gulch in the vicinity of the site. Closer to the City of Rifle, surface water from Government Creek is used for irrigation. The potential for future development of surface water in the region is low and demand is not expected to change. Six private wells have been identified within a two-mile radius of the Estes Gulch Disposal site (see figure 1 of the permit). All are located in alluvial aquifers adjacent to Rifle Creek, Government Creek, or their tributaries. There are no functioning private wells in the Wasatch Formation. No groundwater is used at the Estes Gulch site nor in its immediate vicinity. According to the permittee, the potential for future use of the groundwater at Estes Gulch is low. The U.S. Department of Energy has concluded that the upper 300 feet of the Wasatch Formation cannot sustain pumping rates necessary to supply water for domestic or agricultural use. Unproven water resources may exist at greater depths, but it probably would be uneconomical to develop these supplies. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 5. Permit No. C0-0042757 2. Impacts on Downstream Water Supplies and Other Downstream Classified Uses: (Continued) In addition, as indicated in the M -K Ferguson Company Rifle Processing Sites permit application (Permit No. CO -0042552), there are no identified domestic users of Colorado River water for 20 miles downstream of the City of Rifle. Although there are no known public water supply intakes on the Colorado River downstream of this discharge, segment 1 is classified for drinking water use. With compliance of permit limitations, this facility's discharges should not impact downstream classified water uses in segments 4 and/or 1. IV. Facility Description A. Industry Description M -K Ferguson Company is the remedial action contractor for the Uranium Mill Tailings Remedial Action (UMTRA) project. This UMTRA project at the Rifle Estes Gulch Disposal site was mandated by the Uranium Mill Tailings Raditation Control. Act of 1978 (Public Law 95-604). The UMTRA project is being administered by the U.S. Department of Energy (DOE) Albuquerque operation office. The cleanup at the former Old and New Rifle processing sites, which involves disposal at the Estes Gulch site, is being conducted under the terms of a cooperative agreement between DOE and the State of Colorado. This facility involves a remedial action cleanup of tailings and other contaminated material (soil and debris contaminated with tailings produced by this cleanup) from the former Old Rifle and New Rifle processing sites, with disposal to the Rifle Estes Gulch Disposal site. Maps and facility diagrams of the Rifle Estes Gulch Disposal site are shown in figures 1, 2, and 3 of the permit. Two phases of construction are involved in this overall project. During Phase 1 at the two processing sites, buildings and mill facilities were demolished and added to the tailings pile, some wind blown tailings were moved to the tailings pile, the drainage ditches and retention basin were built, and the access road, fences, decontamination facilities, and on-site construction facilities were constructed. During Phase 2, the disposal site and access road will be prepared and the mill tailings and contaminated material will be removed from the processing sites and placed into an engineered embankment at the disposal site. At this time, Phase 1 activities have been completed and some of the Phase 2 activities have been done. The project lifetime for the Rifle processing and disposal sites remedial activity is estimated to be approximately 3 to 4 years. Moving of mill tailings material is estimated to begin in the Spring of 1992 (April or May) by truck transport to the Rifle Estes Gulch Disposal site. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 6. Permit No. C0-0042757 A. Industry Description (Continued) The source of wastewater to be collected at the Rifle Estes Gulch Disposal site for treatment includes only stormwater runoff. No groundwater is expected to be encountered during the construction and excavation. As previously indicated, the U.S. Department of Energy has concluded that the upper 300 feet of the Wasatch Formation cannot sustain pumping rates necessary to supply water for domestic or agricultural use; thus, no groundwater is expected to be encountered during construction. In addition, the underlying aquifer below the site is over 1000 feet deep; thus, this groundwater should not be encountered either. Discharges of the stormwater source from the retention basin have been projected on a seasonal basis, and were indicated as follows in the permit application. Other months were indicated as periods of no discharge. However, the initial amounts and the actual times of discharges may be different from the original projections. The following gives an estimated indication of the possible amounts and frequency of discharge at the disposal site. Predicted Estes Gulch Disposal Site Outflow from Retention Basin: First Year - March April Second Year - March April May June July August 635,000 gallons (or 0.0205 MGD 332,000 gallons 1,513,000 gallons (or 0.0488 MCD 1,211,000 gallons 868,000 gallons 652,983 gallons 345,000 gallons 100,000 gallons of treated discharge monthly average) discharge (0.0111 MGD) to be discharged monthly average) discharge (0.0404 discharge (0.0289 discharge (0.0218 discharge (0.0111 discharge (0.0323 Third Year - March 1,513,000 gallons discharge Fourth Year - March 1,513,000 gallons discharge MGD) MGD) MGD) MGD) MGD) (0.0488 MGD) (0.0488 MGD) The total estimated discharge is. 8,682,983 gallons for ten months of discharge, which equates to an average flow of 0.0233 MGD during the months of discharge, assuming that discharges would occur continually each day of the ten months. However, the actual total time of discharge may be less than this assumption. This permit is only for the discharge of precipitation and stormwater surface runoff at the site: If toe drainage waters should contribute to the retention basin wastewater at the disposal site, this permit does not include this type of contaminant wastewater source, and an amendment would be necessary before this source could be discharged. Refer to the requirements in Part I.B.11 of the permit which address notification requirements and prior demonstration of compliance requirements in the case where toe drainage from the disposal cell (or other potentially contaminated sources) should contribute to and be part of the wastewater in the retention pond. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 7. Permit No. CO -0042757 A. Industry Description (Continued) If contaminated tailings water and/or disposal toe seepage water are contributed to and are part of the wastewater in the disposal retention basin, then (as discussed in the previous paragraph) this permit would need to be amended. However, this type of impact will probably not occur, since most of the discharges should be from uncontaminated stormwater runoff (above the 10 -year, 24-hour event) at the site. Initially, it is anticipated that the permittee will place any contaminated tailings water collected from the toe drainage system of the disposal cell back into the retention basin prior to the time when stormwater is collected and stored in the retention basin. However, this toe drainage collection wastewater is expected to drain down to the Wasatch Formation ground water, and will not be contained or discharged from the retention basin or the treatment system at the disposal site. If it is found that these contaminated toe drainage collection wastewaters should remain in the retention basin and impact the stored waters there, then the permittee plans to have this water transported for treatment to the Rifle processing wastewater treatment plant. During the construction and use of the Estes Gulch Disposal site, stormwater runoff will be managed to minimize the impact of any off-site surface drainage. Collection ditches and interceptor ditches will be constructed to route stormwater runoff either away from the disposal site or to the retention basin. The retention basin and drainage ditches are to be lined with a high density polyethylene (HDPE) liner. The liner is specified to have a nominal thickness of 40 mils, to have a puncture resistance of 130 lbs. minimum, and to conform to the requirements of the National Science Foundation Standard 54 for flexible membrane liners. The wastewater recirculation pond is located next to the truck and equipment wash decontamination pad. The wastewater recirculation pond has no discharge; this wastewater is recycled (truck wash water goes back to the recirculation pond), or else might be used for land application only on contaminated areas in the site. Sanitary waste from wash sinks, toilets, shower water, and/or employee wash water will probably be collected in portable chemical toilets or a septic tank for off-site disposal. Thus, this wastewater will not enter the retention pond or the recirculation pond. See the following section (Wastewater Treatment Description) for a discussion of the retention pond, recirculation pond, and wastewater treatment plant. Selected on-site monitoring wells not located in the areas of excavation will be left in place throughout and following the remedial action program for assessment in attaining the specified groundwater standards which are required in the Remedial Action Plan (RAP). Monitoring well locations are shown in the RAP. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 8. Permit No. C0-0042757 A. Industry Description (Continued) According to information submitted with the permit application, diesel fuel for equipment will be stored in an above -ground storage tank with a capacity that will be later determined by the sub -contractor. Also, there may be some storage of chemicals used for treatment at the wastewater treatment plant, including: ferrous sulfate, calcium hydroxide (lime), sulfuric acid, barium chloride, and possibly sodium hypochlorite and polymer(s), if needed. B. Wastewater Treatment Description At the Rifle Estes Gulch Disposal site, the contributing sources of wastewater will go to the wastewater retention basin, and then to a portable wastewater treatment plant if necessary. The retention basin, which has a total capacity of 6,419,000 gallons (excluding freeboard), has been designed for containment of stormwater runoff from the 10 -year, 24-hour storm event, plus the sediment that will accumulate over the construction period. The retention basin will be lined with 40 mil thick high density polyethylene liner. Under times of no -discharge for the retention basin (which is anticipated for many months of the operation; see the previous discussion on page 6 of this rationale for the estimated periods of discharge), evaporation in the retention basin and land application on contaminated areas will occur. When discharges occur from the retention basin at the disposal site, sedimentation and chemical precipitation with flocculants would probably first be utilized for in -pond treatment. At the Estes Gulch disposal site, water from the recirculation pond and/or the retention basin may be used as a supplementary source for dust control within the boundaries of the processing site only in contaminated areas. Application will be by a sprinkler system or by water truck with a spray bar. The water will be sprayed under controlled conditions to prevent drift and to ensure that any runoff will return to the basin(s). Effluent quality of the retention basin will be evaluated for the need to utilize additional treatment with a wastewater treatment plant.. At the Rifle disposal site, either an existing portable wastewater treatment facility may be used, or alternative treatment plans might be utilized. The portable WWTP that was used at Durango would probably be utilized; the capacity of this WWTP is 60 gpm or 0.0864 MGD. One possible alternative treatment plan is that any wastewater with higher concentrations of concern from the retention basin might be hauled to the Rifle processing site WWTP for treatment. Figure 3 of the permit shows the disposal site and the location of the retention basin and the WWTP pad. Figure 4 of the permit shows the mobile wastewater treatment plant (WWTP) process diagram. Further details of the treatment processes can be found in the permit file. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 9. Permit No. CO -0042757 B. Wastewater Treatment Description (Continued) The first trailer of the mobile wastewater treatment plant contains equipment for precipitation of metals by adjusting the pH with lime and sulfuric acid. The second trailer contains membrane filters (ultrafiltration) for removal of precipitated solids. A four bed ion exchange unit, which is installed in the third trailer, may be used to remove other substances that are not amenable to precipitation. The flow of wastewater is from trailer 1 to 2, then (if needed) to trailer 3, and then out through discharge point 001. The estimated effluent concentrations and design specifications for the portable water treatment plant which was used in Durango is indicated in Table 1 of Amendment No. 4 rationale of the Durango M -K Ferguson Company permit (permit number C0-0041548). Experience at other UMTRA sites has demonstrated that the concentrations of heavy metals and radionuclides can be reduced to acceptable levels by using a chemical precipitation and filtration wastewater treatment plant. The initial step in the treatment of the wastewater involves acidifying the incoming stream to a pH of 4 to 5 s.u. This acidification serves two purposes. First, it decomposes the soluble hexavalent uranyl carbonate complex present in the water into carbon dioxide and insoluble oxides of uranium. Secondly, it provides the proper chemical environment for the precipitation of arsenic. Following the acidification, ferrous sulfate solution is metered into the stream. The ferrous sulfate acts as a coagulant to assist in the precipitation of arsenic and selenium by co -precipitation with the ferrous oxhvdroxide. Barium chloride is also added into the first reaction tank to treat radium. Lime is added into the first or second reaction tank to increase the pH for enhancing precipitation of metals and radioactive parameters. The precipitates are removed from the system as a thin slurry in a membrane ultrafiltration system. Eventually, this slurry is taken to the disposal cell. The pH of the residual solution from the ultrafiltration system is lowered to the allowable range and then discharged. Since 1984 treatment plants have been operated at UMTRA Project sites at Canonsburg, Pennsylvania, Lakeview, Oregon, Salt Lake City, Utah, and Durango, Colorado. According to the permittee, these previously used treatment plants have successfully utilized two major process steps for treatment at other sites to meet effluent limits to a level consistent with all State and EPA NPDES discharge requirements: Chemical Pre-treatment - The chemical pretreatment was designed for precipitation of selenium, arsenic, radium, uranium, silver, copper, iron, lead, and nickel. Ultrafiltration - Removal of the precipitated solids was accomplished by membrane filtration. This was followed by permeate neutralization to meet the required effluent pH. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 10. Permit No. C0-0042757 B. Wastewater Treatment Description (Continued) In addition to the constituents listed on the previous page, chemical treatment is designed to remove zinc and manganese. However, in addition to treatment for metals and radionuclides, treatment for ammonia and total dissolved solids (TDS) may be necessary if higher contaminated sources are introduced into the retention basin which would impact the wastewater discharge. Thus M -K Ferguson Company may need to consider implementing treatment alternatives for reduction of total ammonia and TDS levels to meet the numeric permit limits for the disposal site. If there is only a discharge of precipitation and uncontaminated stormwater runoff, then treatment for ammonia and TDS will probably not be necessary. However, acute toxicity due to TDS and/or other parameters should still be considered with respect to additional treatment if WET toxicity should occur in the discharges. At the time of permit application, neither a general class of polymers nor a specific polymer had been selected for use in the wastewater treatment plant. The permittee should submit information, including Materials Safety Data Sheets, for the polymers once a final choice is made. Polymers should be chosen which are not toxic to humans or aquatic life at the levels used. The Division reserves the right to include additional requirements because of the polymer used. Sludge and spent resin from treatment operations will be disposed with the tailings in the licensed encapsulation area (landfill disposal area at the Estes Gulch site). The solids that form the sludge come from the WWTP and from the retention basin from both the Rifle processing and disposal sites. The sludge is comprised of silt and solids from the retention basin, metal hydroxide precipitates, and barium sulfate -radium sulfate coprecipitate. The wastewater treatment system will contain numerous monitoring and control points. The proposed methods of effluent flow measurement, as indicated in the permit application, include a turbine meter from the wastewater treatment plant (zero to 75 gpm measurement capacity for outfall 001), and either a broad -crested weir (for lower flows of zero to 79 cfs capacity) or pump capacity (for higher flows of 200 - 800 gpm) from the retention basin (for outfall 002). The wastewater treatment plant will be operated under the supervision of a certified Class B Industrial Wastewater Treatment Plant operator. According to the permittee in the permit application, the names and the certification numbers of operators will be submitted to the Water Quality Control Division after they are selected by the subcontracter. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 11. Permit No. C0-0042757 V. PERFORMANCE HISTORY A. Monitoring Data 1. Discharge Monitoring Reports and Previous Monitoring Data: This is a new facility, thus no treated effluent monitoring data is available. However, the permittee has submitted some information regarding groundwater at the disposal site, as well as groundwater quality data from the processing site. This includes a discussion relating to the groundwater at the disposal site (see under "Industry Description", page 6 of this rationale). Also, the permittee has submitted the average water quality of shallow groundwater at both Rifle processing sites with the individual groundwater well monitoring data in the processing site vicinity that was sampled during October 1987. This information is summarized in the permit application in the Rifle processing sites permit file. The untreated groundwater monitoring data in the permit application indicated levels above this permit's limitations for Total Ammonia in the wells at the New Rifle Processing Site, and levels above this permit's limitations for Total Arsenic and Total Zinc in a few wells at both processing sites. Thus, if contaminated waters from the tailings at the disposal site should impact the retention basin and the discharges from the disposal site, treatment may be necessary for the disposal site to meet permit limits. 2. State Sampling: There are no state sampling results available for this facility. VI. TERMS AND CONDITIONS OF PERMIT A. Effluent Limitations In developing suitable effluent limitations, the Division must review all applicable standards and regulations and apply that which is more stringent. This review includes, but is not limited to, the water quality standard based effluent limitations, federal guidelines and standards (40 CFR Subchapter N), State Effluent Regulations (10.1.0) and Best Professional Judgement limitations. Such a review has been done for this facility. The following limits in Table VI -1 will apply and are discussed in the following section. Table VI -1 -- Effluent Limits for Discharge Points 001 and 002 Parameter Limit Rationale Flow, MGD 0.0864 (001) a/ Average WWTP Design Capacity Report (002) J Flow Assessment Total Suspended Solids, mg/1 20/30 J Best Professional Judgement A/ - 30 -Day Average J - 30 -Day Average/Daily Maximum COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 12. Permit No. C0-0042757 Table VI -1 -- Effluent Limits for Discharge Points 001 and 002 (Continued) Parameter Limit Rationale COD, mg/1 500 B0D5, mg/1 Report Oil and Grease, mg/1 10 pH, s.u. 6.5 - 9.0 Total Residual Chlorine, mg/1 0.5 Total Dissolved Solids, mg/1 515 Total Ammonia, mg/1 as N 320 Total Arsenic, mg/1 0.1/1.0 Total Zinc, mg/1 0.5/1.0 Dissolved Radium 226, pCi/1 3.0/10.0 Total Radium 226 + 228, pCi/1 5.0/30 Total Natural Uranium, mg/1 2.0/4.0 WET - Acute Toxicity IWC -100% / 50% Best Professional Judgement State Effluent Regulations State Effluent Regulations Water Quality Standards State Effluent Regulations State Salinity Regulations Water Quality Standards Water Qual. Stds/ BPJ Best Professional Judgement Best Professional Judgement Best Professional Judgement Water Qual. Stds/ BPJ State Discharge Regulations A/ - 30 -Day Average J - 30 -Day Average/Daily Maximum 2/ - Daily Maximum BPJ — Best Professional Judgement J - Minimum - Maximum A/ - 30 -Day Average/7-Day Average J - See footnote a/ in the permit 1. Water Quality Standard Based Effluent Limitations: A mass balance equation was used to determine the effluent concentrations for those parameters which must be evaluated for this permit and which have assigned water quality standards as specified in segment 4 (Estes Gulch; Government Creek) and segment 1 (Colorado River) of the Colorado River (except in the case of pH, where the limits are set directly from stream standards). The mass balance equation is: Where: Qi Q2 M2 = M3Q3 - M1Q1, Q2 = Upstream low flows from Part III.B.1 = Effluent flow from Part II.G for the total average flows from discharge points 001 and 002 at the disposal site to evaluate segment 4 WQS-based calculations for Estes Gulch or Q2 — Effluent flow for the total average flows from the WWTP discharges for outfalls 001 or 003 from the Rifle processing sites, and outfall 001 from the Rifle disposal site to evaluate segment 1 WQS-based calculations for the Colorado River Q3 — Combined downstream flow (Q1 + Q2) M1 — Upstream background pollutant concentration M2 Unknown; effluent pollutant concentration M3 — Water Quality Standard COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 13. Permit No. C0-0042757 1. Water Quality Standard Based Effluent Limitations: (Continued) A summary of the mass balance calculations are shown in Table VI -2 and discussed on the following pages. The values for Q1, Q2 and Q3 are the same in all of the calculations for water quality limited parameters and are: a) For mass balance equation evaluations involving segment 4 (Estes Gulch and/or Government Creek): Chronic Q1 Q2 Q3 Flow Values 0.0 cfs (or 0.0 MGD) 0.18 cfs (0.115 MGD) 0.18 cfs (0.115 MGD) Acute Flow Values Ql : 0.0 cfs (or 0.0 MGD) Q2 : 0.18 cfs (0.115 MGD) Q2 : 0.18 cfs (0.115 MGD) b) For mass balance equation evaluations involving segment 1 (the Colorado River): Chronic Flow Values Qi: 1400 cfs (or 905 MGD) Q2: 0.69 cfs (0.45 MGD) Q3: 1400.69 cfs (905.45 MGD) Acute Flow Values Q1 : 1200 cfs (or 776 MGD) Q2 : 0.69 cfs (0.45 MGD) Q3 : 1201.69 cfs (776.45 MGD) For assessments involving Estes Gulch and Government Creek (segment 4), the total facility flow (Q2) of 0.18 cfs, or 0.115 MGD, is based upon the average projected flows which would occur from the disposal discharge points 001 and 002. The same chronic discharge flow value is used for the acute discharge flow in the mass balance equations, since the maximum flows are expected to only occur under very unusual circumstances where the 10 -year, 24-hour precipitation event is exceeded. However, regardless of what the total disposal facility discharge flow value is, the same WQS based limitations would apply, since the low flow value for Estes Gulch and Government Creek is 0.0 cfs. For the WQS assessments involving the Colorado River (segment 1), the total facility flow (Q2) of 0.691 cfs, or 0.4464 MGD, is based upon the average projected flows which would occur simultaneously from the WWTP discharge points 001 or 003 at the Rifle processing site and the WWTP discharge point 001 at the Rifle disposal site. Based upon permittee comments and the assumptions made for the WQS mass balance assessment no simultaneous discharge is allowed from both Rifle processing site WWTP discharges and no simultaneous discharge is allowed from both Rifle disposal site discharges. The discharge flows for the processing site outfalls 002 and 004 are not included in the WQS assessment, since these two retention basin discharges (002 and 004) would not occur under the stream low flow conditions that are the basis for the mass balance calculations or under normal stream flow conditions. Discharges from the processing site outfalls 002 and 004 are not expected, except under conditions where the 10 -year, 24-hour precipitation event is exceeded. Similarly, the flow for the disposal site COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 14. Permit No. CO -0042757 1. Water Quality Standard Based Effluent Limitations: (Continued) outfall 002 is not included in the WQS assessment, since a simulataneous discharge from both disposal outfalls is not allowed to occur. Values for M1 and M3 vary depending on the applicable water quality standard (M3) and the background stream quality data (MI). The water quality standards for the parameters limited in this permit are shown in Table VI -2 along with the calculated effluent limitations (M2). The mean upstream background concentration for the Colorado River, which is also summarized in Table VI -2, is from the WQCD Station No. 000047 - Colorado River at New Castle, CO. The ambient upstream data for the Colorado River covers the period from January 4, 1968 through January 3, 1990. The actual data and calculations are in the permit file and are available upon request Table VI -2 Summary of Mass Balance Calculations Parameter Upstream Background Stream Effluent Concentration Standard Limitation Chronic (M1) (M3) (M2) a) WOS Assessment for Segment 4 Estes Gulch and Government. Creek: Total Boron, mg/1 0 Total Cyanide, mg/1 0 Total Recoverable Arsenic, mg/1 0 Total Recoverable Cadmium, mg/1 0 Hexavalent Chromium, mg/1 0 Trivalent Chromium, mg/1 0 Total Recoverable Copper, mg/1 0 Total Recoverable Lead, mg/1 0 Total Recoverable Nickel, mg/1 0 Total Recoverable Selenium, mg/1 0 Total Recoverable Zinc, mg/1 0 Total Radium 226 + 228, pCi/1 0 Total Recoverable Vanadium, mg/1 0 0.75 0.75 0.2 0.2 0.1 0.1 0.01 0.01 0.1 0.1 0.1 0.1 0.2 0.2 0.1 0.1 0.2 0.2 0.02 0.02 2.0 2.0 5.0 f/ 5.0 0.1 J 0.1 J - assumed f/ - 5.0 pCi/1 is the statewide Basic Standard for Total Radium 226 + 228 (reference 1). h/ = 0.1 mg/1 represents a Best Engineering Judgement -derived standard for vanadium, which is the recommended criteria for agricultural usage for livestock watering (reference 4). COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 15. Permit No. C0-0042757 1. Water Quality Standard Based Effluent Table VI -2 -- Summary of Mass Balance Calculations Limitations: (Continued) Parameter Upstream Background Concentration (M1) Stream Standard Chronic (M3) Effluent Limitation (M2) b) WOS Assessment for Segment 1 - Colorado River: Total Residual Chlorine, mg/1 Total Ammonia, mg/1 as N Total Boron, mg/1 Total Chloride, mg/1 Free Cyanide, mg/1 Total Fluoride, mg/1 Total Nitrate, mg/1 as N Total Nitrite, mg/1 as N Total Sulfate, mg/1 Total Sulfide, mg/1 as H2S Potentially Dissolved Aluminum, mg/1 Total Recoverable Arsenic, mg/1 Potentially Dissolved Cadmium, mg/1 Hexavalent Chromium, mg/1 Trivalent Chromium, mg/1 Potentially Dissolved Copper, Dissolved Iron, mg/1 Total Recoverable Iron, mg/1 Potentially Dissolved Lead, mg/1 Dissolved Manganese, mg/1 Total Recoverable Manganese, mg/1 Total Recoverable Mercury, mg/1 Potentially Dissolved Nickel, mg/1 Total Recoverable Selenium, mg/1 Total Recoverable Silver, mg/1 Total Recoverable Thallium, mg/1 Total Recoverable Zinc, mg/1 mg/1 o J 0 J 0.039 126 0.0029 0.30 0.32 0.0055 111 0 J 0.000913 e/ 0.0015 J 0.00025 a/ 0 e/ 0 e/ 0.0056 J 0.10 0.426 0.0059 0 0.0547 0 0.044 0.0022 0 0 0.024 LLuZLL� �L 0.003 0.16 0.75 250 0.005 2.0 10.0 0.05 250 0.002 0.087/0.75 0.05 0.00225/0.0105 0.011/0.016 0.05 0.025/0.040 0.30 1.0 0.013/0.050 0.05 1.0 0.00001 0.185/1.8 0.010 0.00034/0.009 0.000012 0.063/0.22 A/ 5.2 320 1400 434,000 A/ 3.7 3000 17,000 90 507,000 4.1 170/1300 4/ 300 4.0/17.8 4/ 22/28 J 87 40/61 d/ 405 1200 15/77 d/ 100 1900 0.020 4/ 290/3000 4/ a/ 14 1 0.68/12.5 4/ 0.024 4/ 79/340 4/ A/ a/ J J a/ d/ a/ _ J a g/ JID Total Recoverable Arsenic, Total Residual Chlorine, Free Cyanide, Trivalent Chromium, and Tot. Rec. Selenium are acute standards. All other standards are chronic, unless indicated by A/ for metals. assumed 2.0 mg/1 represents a Best Engineering Judgement -derived standard for fluoride, which is the recommended criteria for agricultural usage for livestock watering (reference 4). the chronic/acute numeric standards and the 30 -day average/daily maximum concentration discharge levels. the ambient background concentration was analyzed as total recoverable for most of the indicated parameters; or as total for arsenic, mercury, and selenium. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 16. Permit No. C0-0042757 Table VI -2 -- Summary of Mass Balance Calculations (Continued) b) WOS Assessment for Segment 1 - Colorado River: (Cont.) Total Radium 226 + 228, pCi/1 0 J 5.0 J 8700 Total Natural Uranium, mg/1 0.0036 J 0.06 g/ 98 Total Recoverable Vanadium, mg/1 0 J 0.1 J 200 J - assumed J — 5.0 pCi/1 is the statewide Basic Standard for Total Radium 226 + 228 (reference 1). g/ — 0.06 mg/1 is equal to 40 pCi/1; 40 pCi/1 is the basic standard specified for Total Natural Uranium in 3.7.5(3) of the Classifications and Numeric Standards for the Lower Colorado River Basin 3.7.0 (5 CCR 1002-8). J - 0.1 mg/1 represents a Best Engineering Judgement -derived standard for vanadium, which is the recommended criteria for agricultural usage for livestock watering (reference 4). — mean upstream concentration for Dissolved Natural Uranium 2. Applicable Federal Effluent Guidelines and Standards: Federal technology-based effluent limitations (BAT and BPT).for the Uranium, Radium, and Vanadium Ores Subcategory of the Ore Mining and Dressing Point Source Category (40 CFR 440 Subpart C) are being used as a basis for some effluent limitations for the Rifle Estes Gulch Disposal Site Remedial Action Project. It is felt that wastewater from this site must be of at least the minimal quality provided by the federal standards, and that these limitationsrepresent a best available technology treatment level. The Division believes that this level of treatment can be economically obtained for all the parameters indicated, with the exception of total ammonia. These limits will be included based on Best Professional Judgement. The limitations are in Table VI -3 below. Table VI -3 -- Federal Standards Parameter 30 Day Average Daily Maximum Concentration Concentration pH, s.u. 6.0 - 9.0 a/ Total Suspended Solids, mg/1 20 30 COD, mg/1 500 Total Ammonia, mg/1 100 Total Arsenic, mg/1 0.5 1.0 Total Zinc, mg/1 0.5 1.0 J — range COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 17. Permit No. C0-0042757 2. Applicable Federal Effluent Guidelines and Standards: (Cont.) Table VI -3 -- Federal Standards (Cont.) Parameter 30 Day Average Daily Maximum Concentration Concentration Dissolved Radium 226, pCi/1 3 10 Total Radium 226, pCi/1 10 30 Total Uranium, mg/1 J 2 4 b/ = Federal effluent limitations for total uranium are specified for mine drainage from mines from which uranium, radium, and vanadium ores are produced; the other parameter effluent limitations specified above are for pollutants discharged from mills involved in the extraction of uranium, radium, and vanadium ores, including mill -mine facilities. 3. Regulations for Effluent Limitations: The Regulations for Effluent Limitations (10.1.0), apply to the conventional pollutants. For this facility, the limitations for Total Residual Chlorine (TRC) and Oil and Grease are based on this regulation. Since there could be higher oxygen -demanding organic wastewaters that are associated with uranium mill products/wastes, both COD and BOD5 must be assessed for this permit. As previously discussed, there is a limit for COD in the permit. A BOD5 limit of 30/45 mg/1 exists for waters of the State, as based upon the Regulations for Effluent Limitations. However, instead of including a permit limitation for BOD5 at this time, monitoring for BOD5 is specified for this permit. If levels above 30/45 mg/1 are found to occur in discharges from this facility, then the BOD5 limitations would later be incorporated into the permit. 4. Discussion of Limitations: a) 10 -Year, 24 -Hour Event Exemption Claim Requirements and Water Quality Standard -Based Limitations: This exemption may be applicable for discharge point 002. If the 10 -year, 24-hour precipitation event exemption for the BAT/BPT-based permit limitations is to be claimed for these discharges, appropriate documentation of the event as well as containment verification and a discussion of operational and management practices must be submitted as indicated in Part I.8.13 of the permit. This discussion must also document that the facility is designed, constructed and is being maintained to contain or treat the maximum volume of wastewater as indicated in Part I.B.13.a) and b) of the permit. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 18. Permit No. C0-0042757 4. Discussion of Limitations: (Continued) a) 10 -Year. 24 -Hour Event Exemption Claim Requirements and Water Quality Standard -Based Limitations: In addition, for this storm event exemption to be claimed, M -K Ferguson Company must demonstrate that the following water quality standard -based levels are attained: pH 6.5 - 9.0 s.u. Total Ammonia, as N 320 mg/1 Total Arsenic 0.1 mg/1 Total Recoverable Zinc 2.0 mg/1 Total Radium 226 + 228 5.0 pCi/1 Total Natural Uranium 98 mg/1 For claiming a storm water exemption, M -K Ferguson must also adequately demonstrate that all available management, containment, and treatment options, including the wastewater treatment plant, have been optimally used. As indicated in Section 3.5.5(3)(b) of the "Classifications and Numeric Standards for the Lower Colorado River Basin (5 CCR 1002-8)", the Uranium level in surface waters shall be maintained at the lowest practicable level; and Section 3.5.5(3)(c) states that in no case shall Dissolved Uranium levels in waters assigned a water supply classification be increased by any cause attributable to municipal, industrial, cr agricultural discharges so as to exceed 40 pCi/1. In addition, Section 3.1.11(2) of the "Basic Standards and Methodologies for Surface Waters" states that the Radium 226 and 228 level in surface waters shall be maintained at the lowest practical level. Thus, optimal treatment is to be maintained as much as possible to not only meet the limitations of this permit, but also so not to impact the groundwater concentration limits specified as part of the Remedial Action Plan. b) Stormwater: Although some Best Management Practice requirements of this permit (see Part I.0 of the permit) in part address some stormwater situations for this site, this permit (C0-0042757) does not address all the necessary stormwater requirements for the disposal site at this time. A stormwater permit application will be submitted by the permittee for the Rifle processing sites and disposal site before October 1, 1992. c) Total Ammonia: Based upon information in the Final Remedial Action Plan for the Rifle UMTRA Site (dated August 1991), the ground water monitoring data at the Rifle Disposal Site and the two Rifle Processing Sites indicate the existing ammonium concentrations on the next page. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 19. Permit No. C0-0042757 4. Discussion of Limitations: (Continued) c) Total Ammonia: (Cont.) Rifle Average ammonium conc. — 3.0 mg/1 Estes Gulch Minimum ammonium conc. — K0.05 mg/1 Disposal Site: Maximum ammonium conc. — 8.1 mg/1 Old Rifle Average ammonium conc. — Not Determined Processing Minimum ammonium conc. — K0.05 mg/1 Site: Maximum ammonium conc. — 1.3 mg/1 New Rifle Processing Site: Average ammonium conc. — 249 mg/1 Minimum ammonium conc. — K0.05 mg/1 Maximum ammonium conc. — 3650 mg/1 The above data for the disposal site is for groundwater monitoring well samples from 1987 through 3-10-1990. This data indicates that there are low ammonium concentrations in the Wasatch Formation groundwater occurring below the disposal site; however, as previously mentioned, the upper 300 feet of the Wasatch Formation cannot sustain pumping rates necessary to supply water for domestic or agricultural use. Generally, the ammonium concentration in groundwater at the Old Rifle processing site, where 79% of the groundwater samples were below detectable levels (K0.05 or K0.1 mg/1), does not have the potential water quality impact for this parameter as at the New Rifle processing site. Thus, ammonia treatment will be necessary for the New Rifle processing site. Ammonia treatment may also be necessary at the disposal site if contaminated tailings water should impact waters in the disposal retention basin. However, this type of impact will probably not occur, since the discharges should be from uncontaminated stormwater runoff (above the 10 -year, 24-hour event) at the site. The total ammonia nitrogen limitation (320 mg/1 as N, based upon the water quality standard -based mass balance equation calculation) is in effect for this permit. Thus, M -K Ferguson Company may need to consider implementing treatment alternatives for reduction of total ammonia levels in the discharge(s) at the disposal site to attain the 320 mg/1 total ammonia limit if discharge concentrations should exceed this level; however, with only uncontaminated stormwater discharges, ammonia treatment would probably not be needed at the disposal site. In determining the chronic limitation for total ammonia for this permit, the Division utilized the Colorado Ammonia Model method (or also called the Lewis method). This method was also used for determining the acute total ammonia value, COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 20. Permit No. C0-0042757 4. Discussion of Limitations: (Continued) c) Total Ammonia: (Cont.) which is 2300 mg/1 as N. Since the acute value is so much greater than the chronic limit, and levels below the chronic ammonia limitation must be attained in the treated facility discharges, the acute value is not limited in this permit. Toxicity considerations involved in the WET biomonitoring testing requirements for this permit will necessitate that M -K Ferguson must comply with the total ammonia limit of 320 mg/1 as N. If the 50 % WET acute toxicity level in the facility discharge(s) is found to be due to ammonia concentrations which are within the permit limit of 320 mg/1, then the discharge sample would need to be chemically modified in order to remove the ammonia, and then the permittee would need to demonstrate that no acute toxicity at the 50 % toxicity level is occurring in the discharge due to any other parameters. d) Total Natural Uranium: The Division has based the Total Natural Uranium limitations (2.0/4.0 mg/1) for this facility upon a Best Professional Judgement (BPJ) determination, since the treatment technology for meeting these limits is economically feasible and available. These BPJ levels are necessary (and possibly even lower levels may be necessary) in order to attain the groundwater concentration Uranium limit of 0.044 mg/1 specified as part of the facility's Remedial Action Plan. Since some concentrations of uranium have been detected above the 0.044 mg/1 level in contaminated groundwater below both Rifle processing sites, limitations for Total Natural Uranium are also applicable for the Rifle disposal permit. Also, refer to the items related to uranium that are discussed in Tables VI -2 and VI -3 of the rationale. e) Salinity (Total Dissolved Solids): The Regulation for Implementation of the Colorado Salinity Standards Through the Colorado Discharge Permit Program, (3.10.0) addresses the discharge of total dissolved solids (TDS) to the Colorado River Basin. The objective of this regulation is to provide more detailed guidance in the application of salinity standards developed pursuant to Section 204 of the Colorado Water Quality Control Act. The stated objective of "the Colorado River Salinity Standards is to have, whenever practicable, a no -salt return policy for industrial discharges." For new industrial discharge permits, a report is required as part of the above regulation (3.1.0). Because the regulation provides a waiver from the no -salt discharge requirement when the salt loading reaching the Colorado River is less than one ton per day or 350 tons per year, whichever is less, the Division has chosen to establish this as a permit limit. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 21. Permit No. C0-0042757 e) Salinity (Total Dissolved Solids): (Continued) The permit limit to meet the stated requirement has been established as follows: 350 tons per year is equal to 700,000 pounds per year, which is equal to 1918 pounds per day, which equates to 515 mg/1 as a daily maximum limitation, based upon the total discharge flows of 0.4464 MGD from outfalls 001 or 003 at the Rifle processing sites and outfall 001 at the Rifle disposal site. The discharge quality of stormwater from the Rifle disposal site is not known. However, more recent discharge data from the Durango disposal site has indicated TDS levels above 1 ton per day (with concentrations of 2240 mg/1 and 2850 mg/1, and loadings of 2.5 and 3.6 tons per day). Although this may be due to the presence of groundwater in the pond at the Durango disposal site, some of the previous discharges that did not contain groundwater at Durango had TDS loadings in excess of 1 ton per day (1.1 to 3.1 tons per day). Groundwater in the Wasatch Formation below the Rifle disposal site is considered poor quality, with TDS concentrations in the range of 1,460 to 25,100 mg/1; however, the groundwater below the disposal site is not expected to be pumped or discharged. It is also a requirement of this regulation that all discharges into the Colorado River basin be monitored for TDS on a continual basis. Due to the potential for TDS loadings above 1 ton per day occurring in discharges at this site, the Division has determined that the permittee will need to monitor for TDS on a monthly basis. Also see footnotes g/ and h/ on page.3 of the permit. If the discharges are found to be greater than 1 ton per day and/or 350 tons per year of TDS loading, M -K Ferguson Company may want to submit a report in accordance with the Salinity Regulations, addressing the economic feasibility of salt -removal with respect to obtaining a waiver from the TDS permit limit. Requirements for this report are included in the Rifle Processing Sites permit (see page lk, Part 1.8.15 of that permit). The remaining concern regarding the levels of ITS in these discharges is that the TDS concentrations may be at or above acutely toxic levels, which would affect the WET testing for the discharges. In some cases, a sodium chloride concentration of 2400 mg/1 has caused 50% acute toxicity to Ceriodaphnia dubia and a magnesium chloride concentration of 1592 mg/1 has caused 50% acute toxicity to Daphnia magna. Thus, the TDS concentration will be critical in affecting WET testing results, and treatment of TDS down to lower levels will probably be necessary to comply with the 50 % acute toxicity level. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 22. Permit No. C0-0042757 4. Discussion of Limitations: (Continued) f) Prior Demonstration of Compliance: As indicated in Part I.B.11 of the permit, in the case where toe drainage from the disposal cell, or other potentially contaminated drainage sources, should enter the retention pond, the permittee shall immediately notify the Water Quality Control Division. Prior to the initial discharge of this contributing wastewater source to Estes Gulch from discharge points 001 and 002 being allowed, the permittee shall demonstrate to the satisfaction of the Permits and Enforcement Section of the Division that the treated effluent is in compliance with all the effluent limitations in Part I.A.1 of the permit, including a demonstration that the 50% acute toxicity level in WET testing has been achieved. A prior demonstration of compliance is not necessary for discharges involving only precipitation and stormwater runoff sources. 5. Whole Effluent Toxicity (WET) Testing: For this facility, acute WET testing is required. (See Parts I.A and I.B of the permit.) Purpose of WET Testing: Section 6.9.7 of the "Regulations for the State Discharge Permit System", passed by the Water Quality Control Commission (WQCC), has established the use of WET testing as a method for identifying and controlling toxic discharges from wastewater treatment facilities. WET testing is being utilized as a means to ensure that there are no discharges "in amounts, concentrations or combinations which are harmful to the beneficial uses or toxic to humans, animals, plants, or aquatic life" as required by Section 3.1.11 (1)(d) of the "Basic Standards and Methodologies for Surface Waters". Chemical analysis of effluent has provided only a partial evaluation of the potential impact a discharge could have on the receiving stream. Also, chemical analysis cannot evaluate the synergistic or antagonistic effect of compounds. There are also compounds for which an accurate or reproducable method of chemical analysis has not yet been developed, as well as compounds which are just beginning to be evaluated for toxic effects. WET testing will provide a more comprehensive means of evaluating the toxicity of a discharge than could otherwise currently be accomplished. Instream Waste Concentration (IWC): As a condition of the permit, the permittee will be required to conduct routine monitoring for acute toxicity. An unacceptable level of acute toxicity occurs when 1) there is a statistically significant difference in the mortality (at the 95% confidence level) observed, for Ceriodaphnia sp. (water flea) and fathead minnows, COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 23. Permit No. CO -0042757 Instream Waste Concentration (IWC): (Continued) between the control and any effluent concentration less than or equal to the Instream Waste Concentration (IWC) or 2) a species mortality in any dilution of effluent (including 100% effluent) exceeds 50%. The IWC is determined using the following equation: IWC — [Facility Flow (FF)/(Stream Low Flow (annual) + FF)) X 100% The flows and corresponding IWC for the appropriate discharge point are: Discharge Point Stream Low Flow (1E3) Facility Flow IWC 001 002. 0.0 cfs 0.0 cfs 0.0864 MGD (0.134 cfs) 100 % 0.0283 MGD (0.044 cfs) 100 % The IWC for this permit is 100 %, which represents a wastewater concentration of 100 % effluent to 0 % receiving stream or dilution water. Acute Biomonitoring: Based upon the possibility that certain parameters (total dissolved solids, ammonia, zinc, total residual chlorine, and/or other parameters) may be present at acutely toxic levels in the treated discharge, the Division believes there is reasonable potential for the discharge to interfere with attainment of applicable water quality classifications or standards. In addition, per Section 6.9.7.(4)(a)(i) of the "Regulations for the State Discharge Permit System", the acute toxicity limit and requirements for testing effluents for WET testing shall be incorporated into all new industrial discharge permits. Thus, because of these conditions, the acute toxicity limit has been incorporated into the permit and becomes effective immediately. If an unacceptable level of acute toxicity is identified, the permittee is required to conduct a toxicity incident response and identify a control program to eliminate that toxicity, as identified in Part I.B. of the permit. Once the acute toxicity limitation is effective, the permittee is required to proceed with the automatic enforcement compliance schedule, as identified in Part I.B. of the permit, should a violation occur. Chronic Biomonitoring: The determination as to whether or not an individual facility must conduct chronic WET testing is dependent upon the ratio of the chronic stream low flow (30E3) to the design flow of the wastewater treatment plant, as well as the receiving waters classifications. The water quality standards for inorganic and metal parameters for segment 4 are based upon agricultural uses, but not upon aquatic life uses. Since the receiving waters for segment 4 are not classified as Aquatic Life Class 1, or Aquatic Life Class 2 with aquatic life -based inorganic and metal numeric standards, chronic WET testing is not required at this time. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 24. Permit No. C0-0042757 5. Whole Effluent Toxicity (WET) Testing: (Continued) The permittee should read the WET testing sections of Part I.A. and I.B. of the permit carefully, and should note that the test methods for the toxicity tests are described in detail in the Division guidance document Guidelines for Conductinz Whole Effluent Toxicity Tests. This document should be read thoroughly prior to commencing the required WET testing, to ensure that the permittee is aware of the various test conditions that could affect the test results (e.g., sample holding time). Part I.B. of the permit contains a very rigorous automatic compliance schedule which the permittee is required to follow, if an unacceptable level of toxicity is detected in the discharge. The permit is primarily conditioned so that Division notification provisions of the compliance schedule are triggered from the date of receipt, at the Division, of mailed documents. As every day beyond the allotted time may constitute a day of violation, it may be in the best interest of the permittee to mail documents certified -return receipt requested, so as to establish a record of the submittal. The permittee should be aware that some of the conditions outlined above may be subject to change if the facility experiences a change in discharge, as outlined in Part II.A.1 of the permit. Such changes shall be reported to the Division immediately. 6. Economic Reasonableness Evaluation: Section 25-8-503(8) of the revised (June 1985) Colorado Water Quality Control Act required the Division to "determine whether or not any or all of the water quality standard based effluent limitations are reasonably related to the economic, environmental, public health and energy impacts to the public and affected persons, and are i furtherance of the policies set forth in sections 25-8-192 and 25-8-104." The Regulations for the State Discharge Permit System, 6.1.0, further define this requirement under 6.12.0 and state: "Where economic, environmental, public health and energy impacts to the public and affected persons have been considered in the classifications and standards setting process, permits written to meet the standards may be presumed to have taken into consideration economic factors unless: a) A new permit is issued where the discharge was not in existence at the time of the classification and standards rulemaking, or b) In the case of a continuing discharge, additional information or factors have emerged that were not anticipated or considered at the time of the classification and standards rulemaking." COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 25. Permit No. CO -0042757 6. Economic Reasonableness Evaluation: (Continued) The evaluation for this permit shows that this is a new facility not in existence at the time of water quality standards rulemaking. However, based on available data, the resulting water quality standard -based effluent limitations are determined to be reasonably related to the economic, environmental, public health, and energy impacts to the public and affected persons. If the permittee disagrees with this finding, pursuant to 6.12.0(2)(b) the permittee should submit all pertinent information to the Division during the public notice period. 7. Antidearadation: On March 5, 1991, an antidegradation assessment was made by the Division. Since the receiving stream (segment 4) classifications include recreation class 2 and aquatic life class 2 cold water, an antidegradation review is not required pursuant to section 3.1.8(1)(b) of the "Basic Standards and Methodologies for Surface Water". In addition, the dilution ratio of the stream to the facility discharges is greater than 100 to 1. B. Monitoring and Reporting 1. Monitoring: Table VI -4 lists the monitoring requirements for this facility, including sample type and frequency. Table VI -4 - Monitoring Requirements for Outfalls 001 and 002 Parameter Measurement Frequency Sample Type Flow, MGD Daily Instantaneous Oil and Grease, mg/1 f/ Daily Visual pH, s.u. Daily Grab Total Residual Chlorine, mg/1 Weekly Grab Total Suspended Solids, mg/1 Weekly Grab BOD5, mg/1 Weekly Grab COD, mg/1 Weekly Grab Total Ammonia, mg/1 as N Weekly Grab Total Arsenic, mg/1 Weekly Grab Total Dissolved Solids, mg/1 Monthly Grab Total Zinc, mg/1 Weekly Grab Dissolved Radium 226, pCi/1 Weekly Grab Total Radium 226 and 228, pCi/1 Weekly Grab Total Natural Uranium, mg/1 Weekly Grab Whole Effluent Toxicity, Acute Quarterly - See Part I.B.3&4 Grab COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 26. Permit No. CO -0042757 2. Reporting: M -K Ferguson Company must submit a Discharge Monitoring Report (DMR) on a monthly basis to the Division. This report should contain the required summarization of the test results for parameters shown in Table VI -4 and Part I.B.1 of the permit. See the permit, Part I.B.1 for details on such submission. 3. Additional Monitoring and Reporting: a.) One -Time Analysis: A one-time monitoring required for the following parameters at the disposal site, as indicated below. a.) One -Time Analysis: (Cont.) Total Boron Total Cyanide Total Recoverable Cadmium Trivalent Chromium Hexavalent Chromium Total Recoverable Copper Total Recoverable Lead Total Recoverable Nickel Total Recoverable Selenium Total Recoverable Vanadium analysis is one discharge from Toluene Alpha -BHC Acetone 2,4-D 2,4,5 -TP Gross Alpha Particle Activity (excluding Uranium and Radon) Gross Beta Particle Activity Since some of the inorganic, metal, and/or radioactive parameters have been found at higher concentrations in untreated groundwater monitoring wells at the processing site or no analysis for certain parameters has been submitted, and there is no actual analysis of the treated discharge waters, these parameters will need to be further assessed at the disposal site in the one-time analysis. A one-time analysis of the inorganic and metal parameters indicated above is also necessary to assess the impact upon these water quality standards in segment 4. Another possible source of wastes that is relevant for this permit are certain organic parameters such as wood preservative chemicals or pesticides that have been detected to a limited extent in the ground water monitoring wells (or in the tailings or sludge) as described in the facility Remedial Action Plan. Thus, these chemicals will be required in the one-time discharge analysis. Thus, the monitoring and analysis shall be performed beginning at the first instance of discharge from each outfall at the Rifle disposal site. This data shall be submitted to the Permits and Enforcement Section within 45 days of the sampling dates of discharge. See Part I.3.12 of the permit. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 27. Permit No. CO -0042757 C. Additional Terms and Conditions Office Code 1. Materials Containment Plan: The permittee will be required to submit a Materials Containment Plan. The plan shall address the prevention and containment of spills of materials used, processed or stored at the facility which, if spilled, would have a reasonable probability of having a visible or otherwise detrimental impact on waters of the State. This plan is to be submitted within 90 days of the effective date of the permit. See Part I.F of the permit. 2. Best Management Practices (BMP) Requirements: BMP requirements for optimization of operations and management are included in the permit to minimize the potential impact of any discharge which might occur. BMP requirements are applicable not only to all the discharge points and the retention basin, but also to any other on-site facilities, including the recirculation pond, any storm water diversion/drainage ditches on site, the disposal cell, and materials and/or waste storage areas. Thus, Best Management Practices must be continually implemented to ensure that nothing on-site will impact state waters See Part I.C. of the permit. D. Specific Compliance Requirements 1. Submissions to the Division: The following are specific compliance items which require permittee action. Please check the referenced parts of the permit for details on what is required. Event 90208 Storm Exemption Report 90408 Prior Demonstration of Compliance 90508 Materials Containment Plan Permit Citation Due Date Part I.3.13 90 days after effective date of permit Part I.B.11 prior to discharge Part I.F 90 days after effective date of permit 90608 Inorganic/Radioactive Part I.3.12 - One Time Analysis within 45 days of the sample date (at the first instance of discharge) COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 28. Permit No. CO -0042757 VII. REFERENCES A. Colorado Dept. of Health, Water Quality Control Commission. Basic Standards and Methodologies for Surface Water (3.1.0). Denver: CDH, as revised 10/8/91. B. Colorado Dept. of Health, Water Quality Control Commission. Regulations for Effluent Limitations (10.1.0). Denver: CDH, as revised 1/31/90. C. Colorado Dept. of Health, Water Quality Control Commission. Regulations for the State Discharge Permit System (6.1.0). Denver: CDH, as revised 11/4/91. D. U.S. Environmental Protection Agency. Water Quality Criteria 1972 ("Blue Book"). Wash., D.C.: U.S. Gov't Printing Office, 0.3-73-003, 3/73. E. 40 CFR Part 440. Code of Federal Regulations. Protection of Environment. Wash., D.C.: U.S. Gov't Printing Office, revised as of 7/1/89. Don Holmer January 20, 1992 VIII. CHANGES TO PERMIT AND RATIONALE FOLLOWING PUBLIC NOTICE M -K Ferguson Company submitted only one comment letter dated February 10, 1992 regarding this particular permit. In this letter, the Division was notified that the designated legal contact person has been changed for all of the M -K Ferguson permits. There were no other comments regarding the permit for the Rifle Estes Gulch Disposal facility. Thus, the only change in the permit and the rationale was that the legal contact on page 1 of the rationale was changed to Mr. R.E. Lawrence. Don Holmer April 17, 1992 Permit No.: C0-0042757 County: Garfield AUTHORIZATION TO DISCHARGE UNDER THE COLORADO DISCHARGE PERMIT SYSTEM In compliance with the provisions of the Colorado Water Quality Control Act, (25-8-101 et. seq., CRS, 1973 as amended) and the Federal Water Pollution Control Act, as amended (33 U.S.C. 1251 et. seq.; the "Act") the M -K FERGUSON COMPANY is authorized to discharge from the Uranium Mill Tailings Remedial Action Project at the Rifle Estes Gulch Disposal Site located in: the SW 1/4 of Sec. 14, T5S, R93W, approximately 5 miles north of Rifle on the State Highway 13,.as shown in figures 1 and 2 of the permit. to Estes Gulch, tributary to Government Creek in accordance with effluent limitations, monitoring requirements and other conditions set forth in Part I, and II hereof. All discharges authorized' ,herein shall be consistant with the terms and conditions of this permit. The applicant may demand an adjudicatory hearing within thirty (30) days of the issuance of the final permit determination, per Regulation for the State Discharge Permit System 6.8.0 (1). Should the applicant choose to contest any of the effluent limitations, monitoring requirements or other conditions contained herein, the applicant must comply with Section 24-4-104 CRS 1973 and the Regulation for the State Discharge Permit System. Failure to contest any such effluent limitation, monitoring requirement, or other condition, constitutes consent to the condition by the Applicant. This permit and the authorization to discharge shall expire at midnight, February 28, 1997 Issued and Signed this 23rd day of April, 1992 ' COLORADO DEPARTMENT OF HEALTH David Holm, Director Water Quality Control Division Code: i - 1 Date: 2 - 84 CERTIFIED L� �/y^�,..;ee� 533 I�H1 E SIGNED PART I Page la of 19 Permit No. C0-0042757 A. TERMS AND CONDITIONS 1. Effluent Limitations - Discharge Points 001 and 002 Beginning immediately and lasting through February 28, 1997, the permittee is authorized to discharge from outfall serial numbers: 001, the effluent pipe from the wastewater treatment plant, and 002, the emergency spillway structure from the wastewater retention basin at the Rifle Estes Gulch Disposal Site. Both discharges are prior to entering Estes Gulch, as shown in figure 3 of the permit. In accordance with the Water Quality Control Commission Regulations for Effluent Limitations, Section 10.1.3, and State Discharge Permit System Regulations, Section 6.9.2, 5 C.C.R. 1002-2, the permitted discharge shall not contain effluent parameter concentrations which exceed the following limitations, discharge more than the mass pollutant loadings specified below, or exceed the specified flow limitation. There shall be no simultaneous discharge from outfalls 001 and 002. Effluent Parameter Discharge Limitations 30 -Day Avg a/ 7 -Day Avg a/ Daily Max J Flow, MGD (Discharge Point 001) 0.0864 N/A Report (Discharge Point 002) Report N/A Report Total Suspended Solids, mg/1 20 N/A 30 BOD5, mg/1 Report Report N/A COD, mg/1 N/A N/A 500 Total Residual Chlorine, mg/1 N/A N/A 0.5 Total Ammonia, mg/1 as N 320 N/A Report Total Arsenic, mg/1 0.1 N/A 1.0 Total Zinc, mg/1 0.5 N/A 1.0 Dissolved Radium 226, pCi/1 3.0 N/A 10.0 Total Radium 226 and 228, pCi/1 5.0 N/A 30 Total Natural Uranium, mg/1 2.0 N/A 4.0 Total Dissolved Solids, mg/1 Report N/A 515 Whole Effluent Toxicity, Acute N/A N/A IWC 1006 / 50% J pH - (Standard Units) shall remain between 6.5 and 9.0 2/. Oil and Grease shall not exceed 10 mg/1 J nor shall there be a visible sheen, see footnote LI. There shall be no discharge of floating solids. See Part I.C. for Footnotes Code: i - 2 Date: 1-84, revised 12-87, revised 12-88 B. MONITORING REQUIREMENTS 1. PART I Page lb of 19 Permit No. C0-0042757 Frequency and Sample Type - Outfalls 001 and 002 In order to obtain an indication of the probable compliance or non- compliance with the effluent limitations specified in Section A, the permittee shall monitor all effluent parameters at the following frequencies: Effluent Parameter Measurement Frequency / Flow, MGD Oil and Grease, mg/1 J pH, s.u. Total Suspended Solids, mg/1 BOD5, mg/1 COD, mg/1 Total Residual Chlorine, mg/1 Total Ammonia, mg/1 as N Total Arsenic, mg/1 Total Zinc, mg/1 Dissolved Radium 226, pCi/1 Total Radium 226 and 228, pCi/1 Total Natural Uranium, mg/1 Total Dissolved Solids, mg/1 g/ Whole Effluent Toxicity (WET) - Acute Daily Daily Daily Weekly Weekly Weekly Weekly Weekly Weekly Weekly Weekly Weekly Weekly Monthly J Quarterly - Part Sample Type J Instantaneous Visual Grab Grab Grab Grab Grab Grab Grab Grab Grab Grab Grab Grab I.3.3 & 4 Grab Sampling by the permittee for compliance with the monitoring requirements specified above shall be performed at the following locations: outfall serial number 001, the effluent pipe from the wastewater treatment plant, and outfall 002, the emergency spillway structure from the wastewater retention basin at the Rifle Estes Gulch Disposal Site. Both discharges are prior to entering Estes Gulch, as shown in figure 3 of the permit. See Part I.0 for footnotes. Code: i - 3 Date: 1-84, revised 2-87, revised 12-88 PART I Page lc of 19 Permit No. CO -0042757 B. MONITORING REQUIREMENTS 2. Reporting of Data Reporting of the data gathered in compliance with Part I.B.1 shall be on a monthly basis. Monitoring results obtained during the previous month shall be summarized and reported on Division approved discharge monitoring report forms, postmarked no later than the 28th day of the following month. If no discharge occurs during the reporting period, "No Discharge" shall be reported. Duplicate signed copies of the above report forms shall be submitted to the following addresses: Colorado Department of Health Water Quality Control Division 4210 East llth Avenue Denver, Colorado 80220 Attention: Permits and Enforcement U.S. Environmental Protection Agency Water Management Division NPDES Branch 8WM-C 999 18th Street, Suite 500 Denver, CO 80202-2466 3. Frequency and Sample Type - Acute WET Testing - Discharge Points 001 and 002 Quarterly test results shall be reported along with the Discharge Monitoring Report (DMR) submitted for the end of the reporting calendar quarter (i.e., WET testing results for the calendar quarter ending March 31 shall be reported with the DMR due April 28, with the remaining WET testing reports submitted with DMRs due each July 28, October 28 and January 28). The results shall be submitted on the Acute Toxicity Test report form, available from the Division. Copies of these reports are to be submitted to both the Division and EPA. The permittee shall conduct each acute WET test in general accordance with methods described in the Division guidance document entitled Guidelines for Conducting Whole Effluent Toxicity Tests. The permittee'shall conduct an acute 48-hour WET test using Ceriodaphnia sp., and an acute 96 -hour WET test using fathead minnows. Acute tests will be replacement static tests of a single effluent grab sample. 4. Accelerated Testing - Discharge Points 001 and 002 If an individual toxicity test shows toxicity at any concentration less than or equal to the following Instream Waste Concentration (IWC) Code: i - 4 Date: 1-84, revised 2-87, revised 12-88 WET language revised 12/30/91 PART I Page ld of 19 Permit No. CO -0042757 B. MONITORING REQUIREMENTS 4. Accelerated Testinv - Discharge Points 001 and 002 (Continued) or if 50% species mortality in any dilution (including 100% effluent) is detected in any acute WET test conducted in accordance with this permit, the permittee shall notify the Division verbally within 24 hours and in writing (date of receipt) within 5 days of receipt of written lab test results and proceed with the following compliance schedule. Discharge Point IWC 001 100 % Within 7 days of becoming aware of the toxicity, the permittee shall then begin weekly accelerated testing of the discharge with whichever species has proven (through the first instance of toxicity) to be the most sensitive. The permittee will continue such testing with one species until 2 consecutive weekly tests demonstrate acute toxicity, 2 consecutive weekly tests demonstrate no acute toxicity or a maximum of 5 weekly tests have been conducted. If no acute toxicity was demonstrated in the 2 consecutive weekly tests or in 3 of the 5 weekly tests, the permitee shall resume routine quarterly testing. In all other cases, a pattern of toxicity has been demonstrated and the permittee shall proceed with the Preliminary Toxicity Investigation. When a pattern of toxicity is demonstrated, the permittee shall orally notify the Division within 24 hours of becoming aware of the test result which demonstrates the pattern of toxicity and in writing within 5 days (date of receipt) after receiving the written lab test result which demonstrates the pattern of toxicity. 5. Preliminary Toxicity Investigation - Discharge Points 001 and 002 The permittee will have 15 working days from the date of demonstration of the pattern of toxicity to complete a preliminary toxicity investigation and submit (date of receipt) the results to the Division, in writing. The "date of demonstration" shall be the date the permitte becomes aware of the final test result that established the pattern of toxicity. The preliminary toxicity investigation may include, but is not limited to: additional chemical and biological monitoring, examination of pretreatment program records, examination of discharge monitoring reports, evaluation of treatment processes and chemical use, inspection of material storage and transfer areas to determine if a spill may have occurred, and similar procedures. If the preliminary toxicity investigation identifies a probable toxicant and/or a probable source of toxicity, the permittee shall WET language revised 12/30/91 PART I Page le of 19 Permit No. C0-0042757 B. MONITORING REQUIREMENTS 5. Preliminary Toxicity Investigation - Discharges 001 and 002 (Continued) submit, as part of its final report results, written notification to that effect to the Division. Within 30 days of completing the preliminary toxicity investigation, the permittee shall submit (date of receipt) for the Division's approval a control program to control effluent toxicity, and shall proceed to implement such plan within 7 days following receipt of written approval from the Division. If no probable explanation for toxicity is identified in the 15 -day preliminary toxicity investigation, a Phase I Toxicity Reduction Evaluation (TRE) is required. The permittee shall notify the Division, as part of its final report, of its intent to proceed with the Phase I TRE. If toxicity disappears during the preliminary. toxicity investigation, the permittee shall submit written notification to that effect to the Division. The Division may require the permittee to conduct accelerated testing to demonstrate the continued absence of toxicity. If, after completing any Division directed accelerated testing, no acute toxicity is found to exist, the permittee shall resume normal quarterly testing. 6. Phase I TRE. - Discharge Points 001 and 002 The Phase I TRE performed by the permittee shall be in general accordance with Methods for Toxicity Reduction Evaluations, Phase I Toxicity Characterization Procedures (September, 1988) published by EPA, or in accordance with procedures approved by the Division. If only one species demonstrated toxicity during accelerated testing, then that species alone may be used in the Phase I TRE. The permittee has 45 days from the submission (date of receipt) of the final report on the preliminary toxicity investigation to complete the Phase I TRE and submit (date of receipt) a report to the Division on the results of the study. If the Phase I TRE identifies a probable toxicant and/or a probable source of toxicity, the permittee shall submit written notification to that effect to the Division as part of the report. Within 30 days of submission (date of receipt) of the Phase I TRE, the permittee shall submit (date of receipt) for the Division's approval a control program to control WET, and shall proceed to implement such plan within 7 days following receipt of written approval from the Division. If the Phase I TRE fails to identify a probable toxicant and/or a probable source of toxicity, the permittee shall notify the Division of its findings and proceed with the Phase II TRE. WET language revised 12/30/91 Part I Page if of 19 Permit No. C0-0042757 B. MONITORING REQUIREMENTS 6. Phase I TRE - Discharge Points 001 and 002 (Continued) If toxicity disappears during the Phase I TRE, the permittee shall submit written notification to that effect to the Division. The Division may require the permittee to conduct accelerated testing to demonstrate the continued absence of toxicity. If, after completing any Division directed accelerated testing, no acute toxicity is found to exist, the permittee shall resume normal quarterly testing. 7. Phase II TRE - Discharge Points 001 and 002 A plan for a Phase II TRE shall be submitted (date of receipt) to the Division by the permittee within 60 days of the submission (date of receipt) of the Phase I TRE Report. The Phase II TRE, as submitted to or revised by the Division, shall be incorporated into the permit as a modified compliance schedule. The Phase II TRE plan shall include the scope, methods, procedures, reporting requirements, and schedules. A Phase II TRE may follow either of two directions, as appropriate: toxicant treatability studies, or toxicant/source identification and control studies. Toxicant treatability studies are designed to assess the feasibility of eliminating WET via addition or modification of treatment processes at the wastewater treatment facility. Toxicant/source identification and control efforts are designed to identify toxicants, identify the sources of toxicants, and control whole effluent toxicity by eliminating the introduction of toxicants into the wastewater treatment facility. Toxicity identification studies performed by the permittee shall be in general accordance with accepted methods for Toxicity Identification Procedures and Toxicity Confirmation Procedures. The Phase II TRE permit conditions may be amended, if so requested and justified by the permittee. The Phase II TRE report shall indicate the results of the Phase II TRE study. If the Phase II TRE results in the identification of the toxicants, the sources of toxicants or treatment for elimination of the toxicant, the permittee shall submit for Division approval a control program to control WET within 60 days of submission (date of receipt) of the Phase II TRE Report, and shall proceed to implement such plan within 7 days following receipt of written approval from the Division. If toxicity disappears during the Phase II TRE, the permittee shall submit written notification to that effect to the Division. The Division may require the permittee to conduct accelerated testing to demonstrate the continued absence of toxicity. If, after completing any Division directed accelerated testing, no acute toxicity is found to exist, the permittee shall resume normal quarterly testing. WET language revised 12/30/91 Part I Page lg of 19 Permit No. CO -0042757 B. MONITORING REQUIREMENTS 8. Control Program - Discharge Points 001 and 002 If required pursuant to Part I.B. of this permit, the permittee shall develop a control program to eliminate WET, through the identification and elimination of any toxicants or toxicant sources responsible for WET, or through the identification and implementation of toxicant treatability processes. The control program, along with any cost/benefit analysis to determine whether the costs of construction bear a reasonable relationship to the resulting benefits, shall be submitted within the specified time frames. Such cost benefit analysis shall be used in accordance with Section 25-8-503(8) and (9), C.R.S. The control program, as submitted to or revised by the Division, may be incorporated into the permit. A control program may, include, but shall not be limited to: additional pretreatment requirements imposed on specific indirect permittees by POTW's, modification of internal source control programs by industries, modifications of treatment plants, and/or best management practices for spills, leaks, etc. 9. Toxicity Incident Closure - Discharge Points 001 and 002 If WET is controlled through implementation of numeric limits for specific toxicants, through a control program eliminating toxicants frcm the waste stream, or through the implementation of treatment processes, or if WET disappears and Division required accelerated testing demonstrates the continued absence of toxicity, the toxicity incident response shall be considered closed and normal quarterly monitoring shall resume. If the permittee completes all required phases of the toxicity incident response specified in compliance schedules, and is unable either to identify the causative toxicants and their sources or to identify feasible treatment options, the permittee may petition the Division for relief from further investigation and testing, consistent with the permit regulations. 10. Toxicity Reopener - Discharge Points 001 and 002 This permit may be reopened and modified (following proper administrative procedures) to include new compliance dates, additional or modified numerical permit limitation, a new or different compliance schedule, a change in the whole effluent toxicity testing protocol, or any other conditions related to the control of toxicants if one or more of the following events occur: a. Toxicity has been demonstrated in the effluent and the permit does not contain an toxicity limitation. Revised 12/30/91 Part I Page lh of 19 Permit No. C0-0042757 B. MONITORING REQUIREMENTS 10. Toxicity Reopener - Discharge Points 001 and 002 (Continued) b. The TRE results indicate that the toxicant(s) represent pollutant(s) that may be controlled with specific numerical limits, and the permit issuing authority agrees that the numerical controls are the most appropriate course of action. c. The TRE reveals other unique conditions or characteristics which, in the opinion of the permit issuing authority, justify the incorporation of unanticipated special conditions in the permit. 11. Prior Demonstration of Compliance - Discharge Points 001 and 002 In the case where toe drainage from the disposal cell, or other potentially contaminated drainage sources, should enter the retention pond, the permittee shall immediately notify the Water Quality Control Division. Prior to the initial discharge of this contributing wastewater source to Estes Gulch from discharge points 001 and 002 being allowed, the permittee shall demonstrate to the satisfaction of the Permits and Enforcement Section of the Division that the treated effluent is in compliance with all the effluent limitations in Part I.A.1 of the permit, including a demonstration that the 50% acute toxicity level in WET testing has been achieved. If the toe drainage sources are contributing to discharges from the retention pond, then this permit will need to be amended to include this new contributing wastewater source prior to discharge being allowed. Once the items specified above have been demonstrated and reviewed by the Division and the permit amendment is in effect, then a continued discharge for this contributing wastewater source will be allowed. A prior demonstration of compliance is not necessary for discharges involving only precipitation and stormwater runoff sources. 12. Special Monitoring: One -Time Analysis In order to determine the general quality of water discharged at this facility, the permittee is required to perform a one-time analysis for the following parameters at the specified discharge points. The monitoring and analysis shall be performed at the first instance of discharge after this permit becomes effective. Following analysis, the data shall be submitted to the Permits and Enforcement Section, within forty-five (45) days of the sampling date. Parameters Discharge Points Sample Type See on Next Page 001 and 002 for all parameters Code: i - 6 Date: 1-84, revised 12-88 Grab for all parameters B. MONITORING REQUIREMENTS 12. Special Monitoring: One -Time Analysis Total Boron Total Cyanide Total Recoverable Cadmium Trivalent Chromium Hexavalent Chromium Total Total Total Total Total Recoverable Recoverable Recoverable Recoverable Recoverable Copper Lead Nickel Selenium Vanadium Part I Page li of 19 Permit No. C0-0042757 (Continued) Toluene Alpha -BHC Acetone 2,4-D 2,4,5 -TP Gross Alpha Particle Activity (excluding Uranium and Radon) Gross Beta Particle Activity If evaluation of the data demonstrates a definite or probable violation of water quality standards and/or basic standards, the permit may be amended to incorporate additional monitoring and limitations, as allowed under Part II.3.5 of this permit. Additional monitoring may also be required where the detection limit for a parameter is above the appropriate water quality standards.. 13. Storm Exemption - Facilities Permitted to Discharge - Outfall 002 If the permittee intends to use the 10 -year, 24-hour storm exemption, a report must be submitted within 90 days after the effective date of this permit, documenting that the facility is designed, constructed and is being maintained to contain or treat: a) The maximum volume of wastewater which would be generated by the facility during a 24-hour period without an increase in volume from precipitation; and b) The maximum volume of wastewater resulting from a 10 -year, 24-hour precipitation event, including the volume which would result from all areas contributing runoff to the individual treatment facility (i.e., all runoff not diverted from the active mining area or the mill area). In addition, if discharge occurs as a result of the 10 -year, 24-hour storm volume being exceeded and the permittee wishes to claim an exemption from technology based effluent limitations, the permittee shall submit, within 5 days of the said discharge, documentation that the facilities were maintained to contain or treat the previously specified volumes. The permittee must also submit documentation of the storm event, including the precipitation recorded at the closest official precipitation gauge station (or the permittee's own gauge), the volume of storm runoff produced and the steps taken to maintain treatment and minimize the amount of overflow. PART I Page lj of 19 Permit No. CO -0042757 B. MONITORING REQUIREMENTS 13. Storm Exemption - Facilities Permitted to Discharge - Outfall 002 (Continued) All data/documentation required by this section which can not be reported on applicable discharge monitoring report forms (DMR's) shall be reported in letter form as an attachment to the DMR. For claiming a storm water exemption, M -K Ferguson must also adequately demonstrate that all available management, containment, and treatment options have been optimally used. In addition, for this storm event exemption to be claimed for discharge point 002, M -K Ferguson Company must demonstrate that the following water quality standard -based levels are attained: pH 6.5 - 9.0 s.u. Total Ammonia, as N 320 mg/1 Total Recoverable Arsenic 0.1 mg/1 Total Recoverable Zinc 2.0 mg/1 Total Radium 226 + 228 5.0 pCi/1 Total Natural Uranium 98 mg/1 Submittal of documentation of containment, maintenance, and precipitation records above does not exempt the permittee from the notification requirements of PART II.A.3. of this permit. PART I Page lk of 19 Permit No. CO -0042757 C. BEST MANAGEMENT PRACTICE REQUIREMENTS 1. In order to effectively manage the area to minimize the potential risk of any unintentional release of pollutants, at a minimum the following practices shall be followed for the wastewater retention basin and recirculation pond, collection and/or diversion ditches, and other facility/treatment/storage processes utilized at the site. Management practices shall be followed to ensure that the facility design capacities are maintained and that any discharges are reduced to minimal impact and minimal frequency. Records pertaining to best management practices should be kept in a log. a) Manage water levels in the pond so that permit limitations are met and there is an adequate prevention of any unauthorized potential overflows or bypassess. b) Ensure that materials are compatable with treatment processes, that incompatable materials do not interfere with treatment or storage processes, and that safety, health, and fire hazard prevention measures are practiced. c) Ensure that adequate land application system measures are practiced (if land application is used) at the facility to ensure that no surface runoff ocpurs to surface waters. d) Manage the facility to. prevent tailings material contaminated water, spills, or other contaminants from entering any onsite diversion ditches and/or drainage ditches that may enter surface waters. Maintain facilities in good working conditions and use appropriate preventative measures to ensure adequate materials containment and a minimal pollution impact on site with respect to stormwater runoff, diversion ditches, drainage ditches, and any surface waters. PART I Page 1L of 19 Permit No. CO -0042757 NEW RIFLE SITE 1/2 • TAUGHENBAUGH MESA 0 112 1 SCALE IN MILES • • • • Figure 1 M -K Ferguson Company Rifle Estes Gulch Disposal Site Facility Location EXISTING WATER WELLS WITHIN A TWO-MILE RADIUS OF THE OLD RIFLE, NEW RIFLE, AND ESTES GULCH SITES GRASS MESA LEGEND • - WELL LOCATION 4 - NUMBER OF WELLS AT ONE LOCATION VSR- MUNICIPAL WELL FOR THE VILLAGE OF SOUTH RIFLE ❑ ALLUVIUM SUDDEN CHANGE IN SLOPE (DOWNWARD) PART I Page lm of 19 Permit No.:CO-0042757 v95 C lam 0 v=im = r %L\ Th ~f , REFERENCE: RIFLE COLO. QUADRANGLE, USGS 1982. Figure 2 M -K Ferguson Company EXHIBIT A -I au^ KN 1000 0 1000 2000 3000 SCALE ESTES GULCH DISPOSAL SITE AND VICINITY FEET OUTFALL 001 OUTFALL 002 '1 PART I Page In of 19 Permit No.: CO -0042757 8 W 4 N EXHIBIT A-2 V) J = J UZtai CD a O UJ N W 0 CO ;000. 1111111 �,I.,.�-1 .�\ \ /mo%% RT DRAINAGE DITCH a ii M -K Ferguson Company W a 5 z 0 kJ 0 un+ !:!;:i1;171.4,FNS=w FHPK E l x1=1061 f lr 0 1 :7 U6 ta 111 ,1 • g• r• r • . H• ;viz® PART I Page to of 19 Permit No.. CO -0042757 4s .1. •r -!r Iu1z0 •`Fr 4 e 0 �. SFr® 1• bi E ...� 6. ,:-10 1- 1.1:313"3'3'. 1111111 111 tItI ;It I 11111 11111111 1111111111 1111 t. ,11 elJ 9I J PART I Page 2 of 19 D. FOOTNOTES - APPLICABLE TO PRECEDING PAGES a/ - The thirty (30) day average shall be determined by the arithmetic mean of all samples collected during a thirty (30) consecutive -day period. Samples shall not be used for more than one (1) reporting period. (Not applicable to fecal coliform determinations - please see footnote m/.) b/ - The seven (7) day average shall be determined by the arithmetic mean of all samples taken in a seven (7) day period. Samples may not be used for more than one (1) reporting period. (Not applicable to fecal coliform determinations - please see footnote m/.) c/ - This limitation shall be determined by a single sample or set of samples as required by Part I.B., Sample Type. d/ - When the measurement frequency indicated is quarterly, the samples shall be collected during March, June, September and December, if a continual discharge occurs. If the discharge is intermittent, then samples shall be collected during the period that discharge occurs. If the permittee, using the approved analytical methods, monitors any parameter more frequently than required by this permit, then the results of such monitoring shall be included in the calculation and reporting of the values required in the Discharge Monitoring Report Form or other forms as required by the Division. Such increased frequency shall also be indicated. e/ - Definitions of Sample Type 1. A "composite" sample, for monitoring requirements, is a minimum of four (4) grab samples collected at equally spaced two (2) hour intervals and proportioned according to flow. 2. A "grab" sample, for monitoring requirements, is a single "dip and take" sample. 3. An "instantaneous" measurement, for monitoring requirements, is a single reading, observation, or measurement performed on site. 4. A "continuous" measurement, for flow monitoring requirements, is a measurement obtained from an automatic recording device which continually measures flow. 5. A "visual" observation, for oil and grease monitoring requirements, is observing the discharge to check for the presence of a visible sheen or floating oil. 6. An "in-situ" measurement, for monitoring requirements, is defined as a single reading, observation or measurement taken in the field at the point of discharge. Code: i - 16 Date: 1-84, revised 10-88, revised 12-88 PART I Page 3 of 19 D. FOOTNOTES 7. A "24 hour composite" sample is a combination of at least eight (8) sample aliquots of at least 100 milliliters, collected at equally spaced intervals during the operating hours of a facility over a twenty-four (24) hour period. For volatile pollutants, aliquots must be combined in the laboratory immediately before analysis. The composite must be flow proportional; either the time interval between each aliquot or the volume of each aliquot must be proportional to either the wastewater or effluent flow at the time of sampling or the total wastewater or effluent flow since the collection of the previous aliquot. Aliquots may be collected manually or automatically. f/ - In the event an oil sheen, or floating oil is observed, a grab sample shall be collected, analyzed, and reported on the appropriate DMR. In addition, corrective action shall be taken immediately to mitigate the discharge of oil and grease. A description of the corrective action taken should be included with the DMR. - Where based on a minimum of 5 samples, the permittee demonstrates, to the satisfaction of the Water Quality Control Division, that the level of total dissolved solids (TDS) in the effluent can be calculated based upon the level of electrical conductivity, the permittee may measure and report TDS in terms of electrical conductivity. h/ - TDS shall be sampled on a monthly basis until six samples have been analyzed. A report of "No Discharge" shall not be counted as one of the six samples. Thereafter, monitoring shall continue on a quarterly basis. Following submittal of the initial six sets of monthly data, the Division shall determine whether the permittee is required to submit a report addressing salt removal in accordance with Regulations For Implementation of the Colorado River Salinity Standards Through the NPDES Permit Program, 3.10.0. If the salinity report is required, the Division shall so advise the permittee by letter and the report shall be submitted within 180 days. i/ - This parameter is subject to "Noncompliance Notification" requirements of Part II.A.3.(b)(v) of this permit. j/ - Procedure for determining settleable solids is contained in 40 CFR 434.64. The method detection limit for measuring settleable solids under this part shall be 0.4 ml/1. k/ - Should a precipitation event occur which is greater than the 10 -year, 24-hour event, the permittee shall submit rain gauge or other appropriate documentation in order for an exemption to be claimed. In lieu of such documentation, limitations contained in Part I.A.1.(b), shall apply. Documentation shall be reported as an attachment to the Discharge Monitoring Report for the appropriate period. $/ Code: 1 - 16 Date: 1-84, revised 10-88, revised 12-88 PART I Page 4 of 19 D. FOOTNOTES J - When the most sensitive analytical method which complies with Part I.F.2. of the permit has a detection limit greater than or equal to the permit limit, the permittee shall report "less than the detectable limit", as appropriate. Such reports shall not be considered as violations of the permit limit. The present lowest method detection limits for specific parameters (which have limitations which are, in some cases, less than or equial to the detection limit) are as follows: Total Residual Chlorine 0.05 mg/1 Total Recoverable Cadmium 0.0003 mg/1 Total Recoverable Copper 0.005 mg/1 Total Recoverable Lead 0.005 mg/1 Total Mercury 0.00025 mg/1 Total Recoverable Nickel 0.05 mg/1 Total Recoverable Silver 0.0002 mg/1 Total Recoverable Zinc 0.05 mg/1 The present lowest method detection limits for the dissolved and also potentially dissolved metal parameters are the same as indicated above for the total recoverable parameters. m/ Fecal coliform bacteria average concentration shall be determined by the geometric mean of all samples collected during a thirty (30) consecutive day period. The 7 day average shall be determined by the geometric mean of all samples taken during a seven (7) day period. r/ The potentially dissolved metal fraction is defined in The Basic Standards and Methodologies for Surface Water 3.1.0 (5CCR 1002-8) as: that portion of a constituent measured from the filtrate of a water and suspended sediment sample that was first treated with nitric acid to a pH of 2 or less and let stand for 8 to 96 hours prior to sample filtration using a 0.4 or 0.45 -UM membrane filter. Note the "potentially dissolved" method cannot be used where nitric acid will interfere with the analytical procedure used for the constituent measaured. - There shall be no acute toxicity in the effluent from this discharge point. The acute toxicity limitation is exceeded if 1) a statistically significant difference in mortality (at the 95% confidence level) is observed for either species between the control and any dilution less than or equal to the identified IWC or 2) a species mortality in any dilution of effluent (including 100% effluent) exceeds 50%. Code: i - 17 Date: 9-84, revised 12-87, revised 8-89 PART I .Page 5 of 19 E• REPORTING 1. Signatory Requirements All reports required for submittal shall be signed and certified for accuracy by the permittee in accord with the following criteria: a) In the case of corporations, by a principal executive officer of at least the level of vice-president or his or her duly authorized representative, if such representative is responsible for the overall operation of the facility from which the discharge described in the form originates; b) In the case of a partnership, by a general partner; c) In the case of a sole proprietorship, by the proprietor; d) In the case of a municipal, state, or other public facility, by either a principal executive officer, ranking elected official, or other duly authorized employee. Code: i - 18 Date: 1-84, revised 8-85, revised 3-87, revised 6-87, revised 12-88 PART I Page 6 of 19 F. SPECIAL REQUIREMENTS 1. Materials Containment Plan Pursuant to Sections 6.9.3 (5) and (6)(b) of the Regulations for the State Discharge Permit System, the permittee is required to submit a Materials Containment Plan. Such a plan shall be submitted to the Permits and Enforcement Section, Water Quality Control Division within ninety (90) days after the effective date of this permit and must be implemented. The plan shall include information and procedures for the prevention and containment of spills of materials used, processed or stored at the facility which if spilled would have a reasonable probability of having a visible or otherwise detrimental impact on waters of the State 1/ 2/. The plan shall include, but not necessarily be limited: a) A history of spills which have occurred in the three (3) years preceding the effective date of this permit. The history shall include a causation of the spills and a discussion of preventative measures designed to prevent them from reoccurring; b) A description of the reporting system which will be used to notify responsible facility management, the State Water Quality Control Division, the Environmental Protection Agency, downstream water users within 5 miles downstream of the facility, and local health officials; c) A description of preventative facilities (including overall facility plot) which prevent, contain, or treat spills and unplanned discharges; d) A list which includes the volumes or quantities of all materials used, processed, or stored at the facility which represent a potential spill threat to surface waters. The location of stored material shall be indicated on the facility plot submitted for item c; 1/ If there is no such material present at the site, this shall be indicated in writing and submitted to the Division for review. 2/ If there is material present but the permittee feels there is not a reasonable probability of a spill impacting waters of the State, this shall be documented in writing and submitted to the Division for review. This documentation shall include; 1) distance to nearest surface waters, and; 2) a detailed description of any structure which prohibits the release of material onto the ground or into a conveyance system. Code: i - 20 Date: 1-84, revised 12-88 PART I Page 7 of 19 F. SPECIAL REQUIREMENTS 1. Materials Containment Plan (Continued) e) An implementation schedule for additional facilities which might be required in item c, but which are not yet operational; f) A list of available outside contractors, agencies, or other sources which could be utilized in the event of a spill in order to clean up its effects. If the facility is capable of handling spills in-house, this shall be documented in the plan;. g) Provision for yearly review and updating of the contingency plan, plus resubmission of the plan to the Division if conditions and/or procedures at the facility change the original plan. The foregoing provisions shall in no way render inapplicable those requirements imposed by Section 311 of the Water Pollution Control Act Amendments of 1972, regulations promulgated thereunder, the Colorado Water Quality Control Act, and regulations promulgated thereunder. This plan should be prepared by a professional engineer registered in the State of Colorado. Nothing herein contained shall be construed as allowing any discharge to waters of the State other than through the discharge points specifically authorized in this permit. Nothing herein contained shall be construed as excusing any liability the permittee might have, civil or criminal, for any spill. The submittal of a Spill Prevention Control and Countermeasure Plan (SPCC Plan) as required by 40 CFR Part 112 may satisfy all or part of this requirement. Should additional materials exist on site which are not addressed. in the SPCC Plan, addressing those materials as per the above is required. Code: i - 21 Date: 1-84, revised 12-88 PART I Page 8 of 19 G. GENERAL REQUIREMENTS 1. Representative Sampling Samples and measurements taken as required herein shall be representative of the volume and nature of the monitored discharge. All samples shall be taken at the monitoring points specified in this permit and, unless otherwise specified, before the effluent joins or is diluted by any other wastestream, body of water, or substance. Monitoring points shall not be changed without notification to and approval by the Division. 2. Analytical and Sampling Methods for Monitoring, Analytical and sampling methods utilized. by the discharger shall conform to Colorado Regulations for Effluent Limitations (10.1.5), and to regulations published pursuant to Section 304 (h) of the Clean Water Act. The analytical method selected for a parameter shall be the one that can measure the lowest detected limit for that parameter unless the permit limitation or stream standard for those parameters not limited, is within the testing range of another approved method. 3. Records The permittee shall establish and maintain records. Those records shall include the following: a) The date, type, exact location, and time of sampling or measurements; b) The individual(s) who performed the sampling or measurements; c) The date(s) the analyses were performed; d) The individual(s) who performed the analyses; e) The analytical techniques or methods used; f) The results of such analyses; and g) Any other observations which may result in an impact on the quality or quantity of the discharge as indicated in 40 CFR 122.44 (i)(1)(iii). The permittee shall retain for a minimum of three (3) years records of all monitoring information, including all original strip chart recordings for continuous monitoring instrumentation, all calibration and maintenance records, copies of all reports required by this permit and records of all data used to complete the application for this permit. This period of retention shall be extended during the course of any unresolved litigation regarding the discharge of pollutants by the permittee or when requested by the Division or Regional Administrator of EPA. Code: i - 22 Date: 1-84, revised 12-88 G• PART I Page 9 of 19 GENERAL REQUIREMENTS 4. Flow Measuring Device If not already a part of the permitted facility, within ninety (90) days after the effective date of the permit, a flow measuring device shall be installed to give representative values of effluent quantities at the respective discharge points. Unless specifically exempted, or modified in Part I.B.2 of this permit, a flow measuring device will be applicable at all designated discharge points. At the request of the Water Quality Control Division, or the Environmental Protection Agency, the permittee shall show proof of the accuracy of any flow -measuring device used in obtaining data submitted in the monitoring report. The flow -measuring device must indicate values within ten (10) percent of the actual flow being discharged from the facility. Code: i - 23 Date: 1-84, revised 12-88 PART II A. MANAGEMENT REQUIREMENTS 1. Change in Discharge Page 10 of 19 The permittee shall inform the Division (Permits and Enforcement Section) in writing of any intent to construct, install, or alter any process, facility, or activity that is likely to result in a new or altered discharge, in and shall furnish the Division such plans and specifications which the Division deems reasonably necessary to evaluate the effect on the discharge and receiving stream. The permittee shall submit this notice within two (2) weeks after making a determination to perform the type of activity referred to in the preceding paragraph. Process modifications include, but are not limited to, the introduction of any new pollutant not previously identified in the permit, or any other modifications which may result in a discharge of a quantity or quality different from that which was evaluated in the drafting of the permit including subsequent amendments. Following such notice, the permittee shall be required to submit a aew CDPS application and the permit may be modified to specify and limit any pollutants not previously limited, if the new or altered discharge might be inconsistent with the conditions of the existing permit. In no case shall the permittee implement such change without first notifying the Division. 2. Special Notifications - Definitions -a) Bypass: The intentional diversion of waste streams from any portion of a treatment facility. b) Severe Property Damage: Substantial physical damage to property at the treatment facilities which causes them to become inoperable, or substantial and permanent loss of natural resources which can reasonably be expected to occur in the absence of a bypass. It does not mean economic loss caused by delays in production. c) Spill: An unintentional release of solid or liquid material which may cause pollution of state waters. d) Upset: An exceptional incident in which there is unintentional and temporary noncompliance with permit effluent limitations because of factors beyond the reasonable control of the permittee. An upset does not include noncompliance to the extent caused by operational error, improperly designed treatment facilities, inadequate treatment facilities, lack of preventative maintenance, or careless or improper operation. Code: i - 24 Date: 1-84, revised 12-88 PART II Page 11 of 19 A. MANAGEMENT REQUIREMENTS 3. Noncompliance Notification a) If, for any reason, the permittee does not comply with or will be unable to comply with any discharge limitations or standards specified in this permit, the permittee shall, at a minimum, provide the Water Quality Control Division and EPA with the following information: (i) A description of the discharge and cause of noncompliance; (ii) The period of noncompliance, including exact dates and times and/or the anticipated time when the discharge will return to compliance; and (iii) Steps being taken to reduce, eliminate, and prevent recurrence of the noncomplying discharge. b) The permittee shall report the following instances of noncompliance orally within twenty-four (24) hours from the time the permittee becomes aware of the noncompliance, and shall mail to the Division a written report within five (5) days after becoming aware of the noncompliance: (i) Any instance of noncompliance which may endanger health or the environment; (ii) Any unanticipated bypass; (iii) Any upset which causes an exceedance of any effluent limitation in the permit; (iv) Any spill which causes any effluent limitation to be violated; (v) Daily maximum violations for any toxic pollutants or hazardous substances limited by PART I -A of this permit and specified as requiring 24 hour notification. c) The permittee shall report all other instances of non-compliance not requiring 24-hour notification at the time Discharge Monitoring Reports are submitted. The reports shall contain the information listed in sub -paragraph (a) of this section. Code: i - 25 Date: 1-84, revised 12-88 PART II Page 12 of 19 A. MANAGEMENT REQUIREMENTS 4. Submission of Incorrect or Incomplete Information Where the permittee failed to submit any relevant facts in a permit application, or submitted incorrect information in a permit application or report to the Division, the permittee shall promptly submit the relevant -application information which was not submitted or any additional information needed to correct any erroneous information previously submitted. 5. Bypass The permittee may allow any bypass to occur which does not cause effluent limitations to be exceeded, but if and only if it is for essential maintenance to assure efficient operation. Bypass is prohibited, and the Division may take enforcement action against a permittee for bypass, unless: a) Bypass was unavoidable to prevent loss of life, personal injury, or severe property damage; b) There were no feasible alternatives to the bypass, such as the use of auxiliary treatment facilities, retention of untreated wastes, or maintenance during normal periods of equipment downtime. This condition is not satisfied if the permittee could have installed adequate backup equipment to prevent a bypass which occurred during normal periods of equipment downtime or preventative maintenance; and c) The permittee submitted notices as required in "Bypass Notification", Part II.A.6. 6. Bypass Notification If the permittee knows in advance of the need for a bypass, a notice shall be submitted, at least ten days before the date of the bypass, to the Division and the Environmental Protection Agency (EPA). The bypass shall be subject to Division approval and limitations imposed by the Division and EPA. Code: i - 26 Date: 1-84, revised 12-15-86, revised 12-88 PART II Page 13 of 19 A. MANAGEMENT REQUIREMENTS 7. Upsets a) Effect of an Upset An upset constitutes an affirmative defense to an action brought for noncompliance with permit effluent limitations if the requirements of paragraph b of this section are met. (No determination made during administrative review of claims that noncompliance was caused by upset, and before an action for noncompliance, is final administrative action subject to judicial review.) b) Conditions Necessary for a Demonstration of Upset A permittee who wishes to establish the affirmative defense of upset shall demonstrate through properly signed contemporaneous operating logs, or other relevant evidence that: (i) An upset occurred and that the permittee can identify the specific cause(s) of the upset; and (ii) The permitted facility was at the time being properly operated; and (iii) The permittee submitted notice of the upset as required in Part II.A.3. of this permit (24-hour notice); and (iv) The permittee complied with any remedial measures required under Section 122.7(d) of the federal regulations. c) Burden of Proof In any enforcement proceeding the permittee seeking to establish the occurrence of an upset has the burden of proof. 8. Removed Substances Solids, sludges, or other pollutants removed in the course of treatment or control of wastewaters shall be properly disposed of in a manner such as to prevent any pollutant from such materials from entering waters of the State. Code: i - 27 Date: 1-84, revised 12-88 PART II Page 14 of 19 A. MANAGEMENT REQUIREMENTS 9. Minimization of Adverse Impact The permittee shall take all reasonable steps to minimize any adverse impact to waters of the State resulting from noncompliance with any effluent limitations specified in this permit, including such accelerated or additional monitoring as necessary to determine the nature and impact of the noncomplying discharge. 10. Discharge Point Any discharge to the waters of the State from a point source other than specifically authorized by this permit is prohibited. 11. Reduction, Loss, or Failure of Treatment Facility The permittee has the duty to halt or reduce any activity if necessary to maintain compliance with the effluent limitations of the permit. Upon reduction, loss, or failure of the treatment facility, the permittee shall, to the extent necessary to maintain compliance with its permit, control production, or all discharges, or both until the facility is restored or an alternative method of treatment is provided. This provision for example, applies to power failures, unless an alternative power source sufficient to operate the wastewater control facilities is provided. It shall not be a defense for a permittee in an enforcement action that it would be necessary to halt or reduce the permitted activity in order to maintain compliance with the conditions of this permit. 12. Proper Operation and Maintenance The permittee shall at all times properly operate and maintain all facilities and systems of treatment and control (and related appurtenances) which are installed or used by the permittee to achieve compliance with the conditions of this permit. Proper operation and maintenance includes effective performance, adequate funding, adequate operator staffing and training, and adequate laboratory and process controls, including appropriate quality assurance procedures. This provision requires the operation of back-up or auxiliary facilities or similar systems only when necessary to achieve compliance with the conditions of the permit. Code: i - 28 Date: 1-84, revised 12-88 PART II Page 15 of 19 B. RESPONSIBILITIES 1. Inspections and Right to Entry The permittee shall allow the Director of the State Water Quality Control -Division, the EPA Regional Administrator, and/or their authorized representative, upon the presentation of credentials: a) To enter upon the permittee's premises where a regulated facility or activity'is located or in which any records are required to be kept under the terms and conditions of this permit; b) At reasonable times to have access to and copy any records required to be kept under the terms and conditions of this permit and to inspect any monitoring equipment or monitoring method required in the permit; and c) To enter upon the permittee's premises to investigate, within reason, any actual, suspected, or potential source of water pollution, or any violation of the Colorado Water Quality Control Act. The investigation may include, but is not limited to, the following: sampling of any discharge and/or process waters, the taking of photographs, interviewing permittee staff on alleged violations, and access to any and all facilities or areas within the permittee's premises that may have any affect on the discharge, permit, or alleged violation. d) The Division shall split any sample taken with the permittee if requested to do so by the permittee. 2. Duty to Provide Information The permittee shall furnish to the Division, within a reasonable time, any information which the Division may request to determine whether cause exists for modifying, revoking and reissuing, or terminating this permit, or to determine compliance with this permit. The permittee shall also furnish to the Division, upon request, copies of records required to be kept by this permit. 3. Transfer of Ownership or Control A permit may be transferred to a new permittee if: a) The current permittee notifies the Division in writing 30 days in advance of the proposed transfer date; and Code: i - 29 Date: 1-84, revised 12-88 PART II Page 16 of 19 B. RESPONSIBILITIES 3. Transfer of Ownership or Control (Continued) b) The notice includes a written agreement between the existing and new permittees containing a specific date for transfer of permit responsibility, coverage and liability between them; and c) The current permittee has met all fee requirements of the State Discharge Permit System Regulations, Section 6.16.0. 4. Availability of Reports Except for data determined to be confidential under Section 308 of the Federal Clean Water Act and Regulations for the State Discharge Permit System 6.6.4 (2), all reports prepared in accordance with the terms of this permit shall be available for public inspection at the offices of the State Water Quality Control Division and the Environmental Protection Agency. 5. Modification, Suspension, or Revocation of Permits By the Division All permit modification, termination or revocation and reissuance actions shall be subject to the requirements of the State Discharge Permit System Regulations, Sections 6.6.2, 6.6.3, 6.8.0 and 6.16.0, 5 C.C.R. 1002-2, except for minor modifications. Minor modifications may only correct typographical errors, require a change in the frequency of monitoring or -reporting by the permittee, change an interim date in a schedule of compliance or allow for a change in ownership or operational control of a facility including addition, deactivation or relocation of discharge points where the Division determines that no other change in the permit is necessary. a) This permit may be modified, suspended, or revoked in whole or in part during its term for reasons determined by the Division including but not limited to, the following: (i) Violation of any terms or conditions of the permit; (ii) Obtaining a permit by misrepresentation or failing to disclose any fact which is material to the granting or denial of a permit or to the establishment of terms or conditions of the permit; (iii) Materially' false or inaccurate statements or information in the application for the permit; Code: i - 30 Date: 1-84, revised 12-88 PART II Page 17 of 19 B. RESPONSIBILITIES 5. Modification, Suspension, or Revocation of Permits By the Division (Continued) (iv) Promulgation of toxic effluent standards or prohibitions (including any schedule of compliance specified in such effluent standard or prohibition) which are established under Section 307 of the Clean Water Act, where such a toxic pollutant is present in the discharge and such standard or prohibition is more stringent than any limitation for such pollutant in this permit. b) This permit may be modified in whole or in part due to a change in any condition that requires either a temporary or permanent reduction or elimination of the permitted discharge, such as: (i) Promulgation of Water Quality Standards applicable to waters affected by the permitted discharge; or (ii) Effluent limitations or other requirements applicable pursuant to the State Act or federal requirements; or (iii) Control regulations promulgated; or (iv) Data submitted pursuant to Part I.3 indicates a potential for violation of adopted Water Quality Standards or stream classifications. (v) Removal of a temporary modification to a stream standard thereby requiring the application of the stream standard. c) This permit may be modified in whole or in part to include new effluent limitations and other appropriate conditions where data submitted pursuant to Part I.3.3 indicates that such effluent limitations and conditions are necessary to ensure compliance with applicable water quality standards and protection of classified uses. d) At the request of the permittee, the Division may modify or terminate this permit if the following conditions are met: Code: i - 31 Date: 1-84, revised 12-88 PART II Page 18 of 19 B. RESPONSIBILITIES 5. Modification, Suspension, or Revocation of Permits By the Division (Continued) (i) In the case of termination, the permittee notifies the Division of its intent to terminate the permit 90 days prior to the desired date of termination; (ii) In the case of termination, the permittee has ceased any and all discharges to state waters and demonstrates to the Division there is no probability of further uncontrolled discharge(s) which may affect waters of the State. (iii) The Environmental Protection Agency has been notified of the proposed modification or termination and does not object in writing within thirty (30) days of receipt of notification; (iv) The Division finds that the permittee has shown reasonable grounds consistent with the Federal and State statutes and regulations for such modification, amendment or termination; (v) Fee requirements of Section 6.16.0 of State Discharge Permit System Regulations have been met; and (vi) Requirements of public notice have been met. 6. Oil and Hazardous Substance Liability Nothing in this permit shall be construed to preclude the institution of any legal action or relieve the permittee from any responsibilities, liabilities, or penalties to which the permittee is or may be subject to under Section 311 (0i1 and Hazardous Substance Liability) of the Clean Water Act. 7. State Laws Nothing in this permit shall be construed to preclude the institution of any legal action or relieve the permittee from any responsibilities, liabilities, or penalties established pursuant to any applicable State law or regulation under authority granted by Section 510 of the Clean Water Act. 8. Permit Violations Failure to comply with any terms and/or conditions of this permit shall be a violation of this permit. Code: 1 - 32 Date: 1-84, revised 12-88 PART II Page 19 of 19 B. RESPONSIBILITIES 9. Property Rights The issuance of this permit does not convey any property or water rights in either real or personal property, or stream flows, or any exclusive privileges, nor does it authorize any injury to private property or any invasion of personal rights, nor any infringement of Federal, State or local laws or regulations. 10. Severability The provisions of this permit are severable. If any provisions of this permit, or the application of any provision of this permit to any circumstance, is held invalid, the application of such provision to other circumstances and the application of the remainder of this permit shall not be affected. 11. Renewal Application If the permittee desires to continue to discharge a permit renewal application shall be submitted at least one hundred eighty (180) days before this permit expires. If the permittee anticipates there will be no discharge after the expiration date of this permit, the Division should be promptly notified so that it can terminate the permit in accordance with Part I1.8.6. 12. Confidentiality Any information relating to any secret process, method of manufacture or production, or sales or marketing data which has been declared confidential by the permittee, and which may be acquired, ascertained, or discovered, whether in any sampling investigation, emergency investigation, or otherwise, shall not be publicly disclosed by any member, officer, or employee of the Commission or the Division, but shall be kept confidential. Any person seeking to invoke the protection of this Subsection (2) shall bear the burden of proving its applicability. This section shall never be interpreted as preventing full disclosure of effluent data. 13. Fees The permittee is required to submit payment of an annual fee as set forth in the 1983 amendments to the Water Quality Control Act. Section 25-8-502 (1) (b), and State Discharge Permit Regulations SCCA 1002-2, Section 6.16.0 as amended. Failure to submit the required fee when due and payable is a violation of the permit and will result in enforcement action pursuant to Section 25-8-601 et. seq., C.R.S. 1973 as amended. Code: i - 33 Date: 1-84, revised 12-88