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HomeMy WebLinkAboutWell Permit 0042552COLORADO 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) 5434441 OFAHEALTH ROY ROMER Governor JOEL KOHN Interim Executive Director January 31, 1991 J. G. Oldham, Project Director P.O. Box 9136 Albuquerque, New Mexico 87119 CERTIFIED MAIL NO: P 784 025 377 RE: Final Permit, Colorado Wastewater Discharge Permit System Number: CO— 0042552 - M -K FERGUSON COMPANY Gentlemen: ii'` FEB 1 0 1992 GARFIELD COUNTY r 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, �7f 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 pnnln(nn .Vf.cf.4 nye: 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 OLD AND NEW PROCESSING SITES PERMIT NUMBER: CO -0042552, GARFIELD COUNTY I. TYPE OF PERMIT: II. FACILITY INFORMATION: A. Facility Type and Fee Category: B. SIC Nos.: C. Legal Contact: CONTENTS TYPE FACILITY INFORMATION RECEIVING STREAM FACILITY DESCRIPTION PERFORMANCE HISTORY TERMS AND CONDITIONS REFERENCES CHANGES FOLLOWING PUBLIC D. Facility Contacts: New - Industrial PAGE 1 1 3 5 10 10 25 NOTICE 25 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) J. G. Oldham, 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. C0-0042552 E. Facility Location: The Old Rifle Processing Site is located in the E 1/2, NE 1/4 of Sec. 16 and the W 1/2, NW 1/4 of Sec. 15, T6S, R93W, aproximately 0.3 miles east of the center of Rifle on the south side of U.S. Highway 6 . The New Rifle Processing Site is in the SE 1/4 of Sec. 18, T6S, R93W, 2 miles west of the center of Rifle on the south side of U.S. Highway 6. Both the old and new processing sites are shown in figures 1 and 2 of the permit. F. Discharge Points: 001 - the effluent pipe from the wastewater treatment plant at the Old Rifle Processing Site, and prior to mixing with the Colorado River, as shown in figures 1 and 3 of the permit. From outfall 001, the discharged water will flow overland by natural drainage to an existing culvert which carries water beneath the railroad track and into the Colorado River. 002 - the emergency spillway structure from the retention pond at the Old Rifle Processing Site, and prior to mixing with the Colorado. River, as shown in figures 1 and 3 of the permit. 003 - the effluent pipe from the wastewater treatment plant at the New Rifle Processing Site, and prior to mixing with the Colorado River, as shown in figures 2 and 4 of the permit. From outfall 003, the discharged water will flow overland by natural drainage to an existing 36 inch culvert located about 200 feet SE of the retention basin. This culvert will carry water beneath Highway I-70 to the Colorado River. 004 - the emergency spillway structure from the retention pond at the New Rifle Processing Site, and prior to mixing with the Colorado River, as shown in figures 2 and 4 of the permit. 005 - a stormwater transfer pipe at the Old Rifle Processing Site which goes to the Colorado River, as shown in figures 1 and 3 of the permit. This pipe is an enclosed 36 inch diameter reinforced concrete pipe that will transport uncontaminated stormwater runoff from areas upgradient of the Old Rifle site. This outfall is being applied for as part of the stormwater discharge permit for this COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 3. Permit No. C0-0042552 F. Discharge Points: (Cont.) G. Discharge Flows: III. RECEIVING STREAM: 005 - facility; however, certain BMP requirements for 005 are being included in this permit (C0-0042552). 001: 0.360 MGD, or 250 gpm (average and daily maximum flows) 0.432 MGD (300 gpm; maximum WWTP capacity) 002: 0 - 0.20 MGD (projected monthly average and daily maximum flow range when discharging) 003: 0.360 MGD, or 250 gpm (average and daily maximum flow) 0.432 MGD (300 gpm; maximum WWTP capacity) 004: 0 - 0.37 MGD (projected monthly average and daily maximum flow range when discharging) 005: Not Determined It should be noted that outfalls 002 and 004 are emergency spillways from the retention ponds, and the permittee has indicated that under most circumstances no discharge from these points are expected (except for possible discharges when the 10 -year, 24 hour precipitation event is exceeded). For further information regarding outfall 005, refer to page 16 of this rationale. A. Identification, Classification and Standards 1. Identification: The M -K Ferguson Rifle Old and New Processing Site outfalls will be discharging to the Colorado River, segment 1 of the Lower Colorado River Sub -basin, Colorado River Basin (Region 11). 2. Classifications: Segment 1 is classified for the following existing uses: High Quality, Class 2; Recreation, Class 1; Aquatic Life, Class 1 (Cold); Water Supply; Agriculture. 3. 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 which have been reviewed with respect to this facility's discharge include: Physical and Biological pH — 6.5 - 9.0 s.u. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Rationale - Page 4. Permit No. CO -0042552 3. Numeric Standards: (Continued) Inorganic Ammonia (NH3), unionized Cyanide, free Sulfide as H2S, undis. Boron (B) Nitrite (NO2) Nitrate (NO3) Chloride (C1) Sulfate as SO4 Metals Division ▪ 0.02 mg/1 0.005 mg/1 ▪ 0.002 mg/1 — 0.75 mg/1 — 0.05 mg/1 — 10.0 mg/1 — 250.0 mg/1 — 250.0 mg/1 Arsenic (acute) — 0.05 mg/1 Cadmium (chronic) — 0.0022 mg/1* Cadmium (acute) — 0.0105 mg/1* Chromium, tri (ac)— 0.05 mg/1 Chromium, hex (ch)— 0.011 mg/1 Chromium, hex (ac)— 0.016 Copper (chronic) — 0.025 Copper (acute) — 0.040 Iron, total (ch) — 1.0 Iron, dis. (ch) — 0.3 Lead (chronic) — 0.013 mg/1 mg/1* mg/1* mg/1 mg/1 mg/1* Lead (acute) Manganese (tot) Manganese (dis) Mercury (chr.) Nickel (chronic) Nickel (acute) Selenium (acute) Silver (chronic) Silver (acute) Zinc (chronic) Zinc (acute) — 0.05 mg/1 — 1.0 mg/1 — 0.05 mg/1 — 0.00001 mg/1 — 0.19 mg/1* — 1.8 mg/1* — 0.01 mg/1 — 0.00034 mg/1* — 0.0091 mg/1* — 0.063 mg/1* — 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. 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 flow for the Colorado River is based upon USGS Gage No. 09085100, Colorado River below Glenwood Springs, for the period of record from 1978 to 1987. The flows have been determined by the Water Quality Control Division and 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, there are no identified domestic users of Colorado COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 5. Permit No. CO -0042552 2. Impacts on Downstream Water Supplies and Other Downstream Classified Uses: (Cont.) 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 discharge should not impact downstream classified water uses in segment 1. However, since there are rare or endangered species (such as the razorback sucker, Xyrauchen texanus) in the vicinity of the Colorado River near Rifle, this facility is not allowed to discharge until compliance with all the limitations of this permit, including the 50% WET acute toxicity level, has been demonstrated. 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 former Old and New Rifle processing mill sites and new 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 Rifle processing sites are 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 which are shown in figure 1 through 4 of the permit. Two phases of construction are involved in this project. During Phase 1, 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 by truck transport to the disposal site. The Rifle Estes Gulch disposal site operation is located approximately 4 miles north of Rifle in the SW 1/4 of Sec. 14, TSS, R93W. The disposal site will be covered under another permit, CO -0042757. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 6. Permit No. CO -0042552 A. Industry Description (Continued) The sources of wastewater to be collected for treatment include stormwater runoff and groundwater from excavation dewatering. Discharges of these two sources from the retention basins have been projected on a seasonal basis, and were indicated as follows. 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 both processing sites. Predicted Old Rifle Processing Site Outflow from Retention Basin: First Year - March 211,000 gallons of treated discharge Second Year March 5,352,000 gallons to be discharged April 5,141,000 gallons discharge May 6,177,000 gallons discharge Third Year - March 211,000 gallons discharge Predicted New Rifle Processina Site Outflow from Retention Basin: First Year - March 686,000 gallons of treated discharge Second Year March 686,000 gallons to be discharged August 10,714,000 gallons discharge Sept. 10,714,000 gallons discharge Octob. 10,714,000 gallons discharge Nov. 10,714,000 gallons discharge Third Year - March 11,400,000 gallons discharge April 10,714,000 gallons discharge May 10,714,000 gallons discharge June 10,714,000 gallons discharge July 10,714,000 gallons discharge During the cleanup of the abandoned uranium mill processing sites near Rifle, stormwater runoff from the existing tailings piles and groundwater from excavation dewatering operations will be managed to minimize the impact of any off-site surface drainage. Temporary drainage ditches will be constructed to route stormwater runoff from each processing site to their respective retention basins. Runoff from upgradient uncontaminated areas at the Old Rifle Site will be diverted, via an enclosed pipe, and discharged into the Colorado River through an existing culvert (outfall 005), without flowing into the retention basin. At the New Rifle Processing Site, all the site drainage will flow into the wastewater retention basin. Due to the local topography, there is no runoff into the New Rifle site from areas beyond the project boundary. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 7. Permit No. C0-0042552 A. Industry Description (Continued) Groundwater from the excavation areas will be dewatered to just below the depth of excavation and placed into the retention basins. At the Old Rifle Site a slurry trench will be placed at the southern end of the tailings pile to prevent further large influxes of groundwater and from the Colorado River. Dewatering at this site will only occur for a limited period (approximately 3 months). At the New Rifle Site a slurry trench will not be built as the depth of contaminated material excavation is a maximum of 5 feet. The retention basins 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 ponds, which°are located next to the truck and equipment wash decontamination pad at each site, are located north of the retention basin at both the Old Rifle and New Rifle Processing Sites. The wastewater recirculation ponds have 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. The processing site facilities are shown in figures 3 and 4 of the permit. 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. Sanitary waste from wash sinks, toilets, shower water, and/or employee wash water will go to the City of Rifle sanitary sewer system. 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 ponds, recirculation ponds, and wastewater treatment plants. According to information submitted with the permit application and later comments, the sub -contractor may store diesel fuel for equipment 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, sodium hypochlorite, and polymer (if needed). B. Wastewater Treatment Description At each of the two processing sites, the contributing sources of wastewater will go to a wastewater retention basin, and/or to a wastewater treatment plant. The retention basins, which have capacities of 925,000 gallons at the Old Rifle Processing site and COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 8. Permit No. CO -0042552 B. Wastewater Treatment Description (Continued) 1,688,000 gallons at the New Rifle Processing site, have both 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. Under certain times of no -discharge for the retention basins, evaporation in the retention basins and land application on contaminated areas will occur. When discharges occur from the retention basin at the Old Rifle site, sedimentation and chemical precipitation with flocculants would probably first be utilized for in -pond treatment; however, due to the quality and quantity of the contributing wastewater sources at the New Rifle processing site, in -pond treatment will probably not be used for this retention basin and the wastewater treatment plant will need to be used instead. At both the Old Rifle and New Rifle processing sites, 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 retention basins. Effluent quality of the retention basins will be evaluated for the need to utilize additional treatment with a wastewater treatment plant. At these two Rifle processing sites, either an existing wastewater treatment facility may be used, or alternative treatment plans might be utilized. Experience at other UMTRA sites has demonstrated that the concentrations of heavy metals and radionuclides can be reduced to acceptable levels be 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 oxhydroxide. At this point the precipitates of uranium, arsenic, and selenium are removed from the wastewater. This settling is done in an inclined baffle separator. Polyelectrolytes may be used to enhaunce the sedimentation rate. The pH of the clarified overflow from the separator is raised to a level between 10 and 11 to precipitate the remaining metals as insoluble hydroxides. The precipitates are removed from the system as a thin slurry in a membrane ultrafiltration system. The slurry is further concentrated in a gravity settler and disposed of in the tailings pile. The pH of the residual solution from the ultrafiltration system is lowered to the allowable range and then discharged. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 9. Permit No. CO -0042552 B. Wastewater Treatment Description (Continued) 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. In addition to the constituents listed above, 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) are both necessary in order to attain the permit limits for these two parameters. Thus, M -K Ferguson Company will need to consider implementing treatment alternatives for reduction of total ammonia and TDS levels to meet the numeric permit limits. The permittee originally proposed that ammonia removal would be achieved by either air stripping at an alkaline pH, biodenitrification, or by means of another wastewater treatment addition or facility. The latest evaluations have resulted in a proposed treatment for ammonia and TDS by a vapor recompression/ion exchange wastewater treatment system. However, according to the permittee, an on-going evaluation is being done in order to select the most cost effective method for ammonia and TDS reduction. 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. The sludge is comprised of silt and solids from the retention basin, metal hydroxide precipitates, and barium sulfate -radium sulfate coprecipitate. The wastewater treatment plant(s) will contain numerous monitoring and control points. Influent flows are measured by a magnetic flow COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 10. Permit No. CO -0042552 B. Wastewater Treatment Description (Continued) meter; effluent flows are measured by a turbine meter; pH electrodes, connected to a variable speed metering pump, control pH at four points; and a turbidimeter measures effluent quality. Periodic analyses will be made of influent and effluent waters. The proposed methods of effluent flow measurement, as indicated in the permit application, include a turbine meter from the wastewater treatment plants (for outfalls 001 and 003), and either a broad -crested weir (for lower flows) or pump capacity (for higher flows of 200 -.800 gpm) from the retention basins (for outfalls 002 and 004). 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 sub-contracter. 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, a projected analysis of the discharge water quality, as well as the average water quality of shallow groundwater at both Rifle processing sites with the individual groundwater well monitoring data that was sampled during October 1987, have been submitted by the permittee. This information is summarized in the permit application in the 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 sites. Thus, treatment will be necessary at the processing sites 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. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 11. Permit No. C0-0042552 • A. Effluent Limitations (Continued) Such a review has been done for this facility. The following limits in Table VI -1 below will apply and are discussed in the following section. Table VI -1 -- Effluent Limits for Discharge Points 001, 002, 003 and 004 Parameter Limit Rationale Flow, MGD Total Suspended Solids, COD, mg/1 BOD5, mg/1 Oil and Grease, mg/1 pH, s.u. Total Residual Chlorine, mg/1 Total Dissolved Solids, mg/1 Total Ammonia, mg/1 as N Total Arsenic, mg/1 Total Zinc, mg/1 Dissolved Radium 226, pCi/1 Total Radium 226 + 228, pCi/1 Total Natural Uranium, mg/1 2.0/4.0 WET - Acute Toxicity IWC -0.1Z / 50% WET - Chronic Toxicity Report mg/1 0.360 Report 0.360 Report 20/30 500 Report 10 6.5 - 9.0 0.5 515 320 0.5/1.0 0.5/1.0 3.0/10.0 10/30 (001) a/ (002) JJ (003) a/ (004) JJ J J J J 4/ J J J J J J J J Js/ J Mass Flow Mass Flow Best Balance; Average Design Assessment Balance; Average Design Assessment Professional Judgement Best Professional Judgement State Effluent Regulations State Effluent Regulations Water Quality Standards State Effluent Regulations State Salinity Regulations Water Quality Standards Best Professional Judgement Best Professional Judgement Best Professional Judgement Best Professional Judgement Best Professional Judgement State Discharge Regulations State Discharge Regulations J - 30 -Day Average J - Minimum - Maximum J - 30 -Day Average/Daily Maximum J - 30 -Day Average/7-Day Average a/ - Daily Maximum 2/ - See footnote 2/ in the permit - Outfalls 002 and 004 are emergency spillways from the retention ponds; the permittee has indicated that no discharge from these points are expected. 1. Water Ouality 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 1 of the Colorado River (except in the case of pH, where the limits are set directly from stream standards). The mass balance equation is: M2 — M3Q3 - M1Q1, Q2 COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 12. Permit No. CO -0042552 1. water Ouality Standard Based Effluent Limitatidns: (Continued) Where: Q1 Upstream low flow from Part III.B.1 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 Q3 = Combined downstream flow (Q1 + Q2) M1 = Upstream background pollutant concentration M2 = Unknown; effluent pollutant concentration M3 = Water Quality Standard (WQS) 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: Chronic Flow Values Q1 02 : Q3 1400 cfs (or 905 MGD) 0.69 cfs (0.45 MGD) 1400.69 cfs (905.45 MGD) Acute Flow Values Q1 : 1200 cfs (or 776 MGD) Q2 : 0.69 cfs (0.45 MGD) Q3 : 1200.69 cfs (776.45 MGD) The total facility flow (Q2) of 0.69 cfs, or 0.45 MGD, that is used for the WQS assessment 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. The discharge flows for outfalls 002 and 004 are not included in the WQS assessment, since these two Rifle processing site 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 002 and 004 are not expected, except under conditions where the 10 -year, 24-hour precipitation event is exceeded. Values for M1 and M3 vary depending on the applicable water quality standard (M3) and the background stream quality data (M1). 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, 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 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. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 13. Permit No. CO -0042552 1. Water Oualitv Standard Based Effluent Limitations: Table VI -2 -- Summary of Mass Balance Calculations (Continued) Parameter Upstream Background Stream Concentration Standard Chronic (M1) (M3) Effluent Limitation (M2) 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, mg/1 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 Total Radium 226 + 228, pCi/1 0 0 0.039 126 0.0029 0.30 0.32 0.0055 111 0 0.000913 0.0015 0.00025 0 0 0.0056 0.10 0.426 0.0059 0 0.0547 0 0.044 0.0022 0 0 0.024 0 b/ b/ e/ b/ b/ e/ e/ b/ b/ e/ b/ 0.003 a/ 0.16 0.75 250 0.005 a/ 2.0 c/ 10.0 0.05 250 0.002 0.087/0.75 d/ 0.05 a/ 0.00225/0.0105 d/ 0.011/0.016 d/ 0.05 a/ 0.025/0.040 d/ 0.30 1.0 0.013/0.050 d/ 0.05 1.0 0.00001 0.185/1.8 .d/ 0.010 a/ 0.00034/0.0091 0.000012 0.063/0.22 d/ 5.0 f/ 5.2 320 1400 434,000 3.7 3000 17,000 90 507,000 4.1 170/1300 d/ 300 4.0/17.8 d/ 22/28 d/ 87 40/61 d/ 405 1200 15/77 d/ 100 1900 0.020 290/3000 d/ 14 0.68/12.5 d/ 0.024 79/340 d/ 8700 A/ = 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 d/ for metals. b/ assumed c/ 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). d/ the chronic/acute numeric standards and the 30 -day average/daily maximum concentration discharge levels. e/ = the ambient background concentration was analyzed as total recoverable for most of the indicated parameters; or as total for arsenic, mercury, and selenium. f/ = 5.0 pCi/1 is the statewide Basic Standard for Total Radium 226 + 228 (reference 1). COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 14. Permit No. CO -0042552 Table VI -2 -- Summary of Mass Balance Calculations (Continued) Total Natural Uranium, mg/1 0.0036 i/ 0.06 g/ 98 Total Recoverable Vanadium, mg/1 0 b/ 0.1 h/ 200 b/ = assumed 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). 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). i/ = 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 Processing Sites 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 limitations represent 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 V1-3 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 Dissolved Radium 226, pCi/1 3 10 Total Radium 226, pCi/1 10 30 Total Uranium, mg/1 b/ 2 4 a/ = range 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. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 15. Permit No. CO -0042552 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 BODS must be assessed for this permit. As previously discussed, there is a limit for COD in the permit. A BODS 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 BODS 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 Oualitv Standard -Based Limitations: This exemption may be applicable for discharge points 002 and 004. 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.8.14 of the permit. This discussion must also document that the facility is designed, constructed and is beina maintained to contain or treat the maximum volume of wastewater as indicated in Part I.B.14.a) and b) of the permit. 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: Total Ammonia, as N Total Arsenic Total Recoverable Zinc Total Radium 226 + 228 Total Natural Uranium 320 mg/1 300 mg/1 79 mg/1 8700 pCi/1 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 Basins (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 COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 16. Permit No. CO -0042552 4. Discussion of Limitations: (Continued) a) 10 -Year. 24 -Hour Event Exemption Claim Requirements and Water Quality Standard -Based Limitations: (Cont.) increased by any cause attributable to municipal, industrial, or agricultural discharges so as to exceed 40 pCi/l. 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 Outfall 005: As previously described in Section II.F. of this rationale, outfall 005 is an enclosed stormwater transfer pipe at the Old Rifle site. This outfall will be identified in the stormwater permit application for the Rifle sites, and will be covered at that time. In a later comment letter (dated December 4, 1991), the permittee indicated that as part of the BMP for this site, outfall 005 is being taken out of sevice. This permit (CO -0042552) does not address the necessary stormwater requirements for outfall 005 at this time. 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 each site indicates the following existing ammonium concentrations: Old Rifle Site: Average Minimum Maximum New Rifle Site: Average Minimum Maximum ammonium conc. ammonium conc. ammonium conc. ammonium conc. ammonium conc. ammonium conc. — Not Determined — K0.05 mg/1 — 1.3 mg/1 — 249 mg/1 — K0.05 mg/1 — 3650 mg/1 The above data is for ground water monitoring well samples from 1987 through 9-18-1990. Generally, the ammonium concentration in ground water at the Old Rifle site, where 79% of the ground water 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 site. Thus, ammonia treatment will be necessary for the New Rifle 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 will need to consider implementing treatment alternatives for reduction of total ammonia levels in the discharge to attain the 320 mg/1 total ammonia limit. In determining the chronic limitation for total COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 17. Permit No. C0-0042552 4. Discussion of Limitations: (Continued) c) Total Ammonia: (Cont.) 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, 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 X 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 applicable for this permit. 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 18. Permit No. C0-0042552 4. Discussion of Limitations: (Continued) e) Salinity (Total Dissolved Solids): (Cont.) 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. From untreated ground water monitoring data from the Old Rifle Processing site, it appears that this TDS limit may not be attained at outfalls 001 and 002, since the estimated concentration of TDS is 1254 mg/1 at the Old Rifle site. Also, at the New Rifle Processing site, the 515 mg/1 TDS limit will probably not be attained without additional treatment, since the estimated TDS concentration from the contaminated groundwater in this vicinity is 21,000 mg/1. 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 higher TDS concentrations potentially occurring at this site, the Division has determined that the permittee will need to monitor for TDS on a monthly basis. Since the discharge(s) will be greater than 1 ton per day of TDS loading, the Division has determined that the permittee will be required 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. This report will be due by April 30, 1992; see Part I.8.13 for further details required in the report. Also see footnotes g/ and h/ on page 3 of the permit. The remaining concern regarding the levels of TDS 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 mama. Thus, the TDS concentration will be critical in affecting WET testing results, and treatment of TDS levels will probably be necessary to comply with the 50 X acute toxicity level. f) Prior Demonstration of Compliance: As indicated in Part I.6.10 of the permit, prior to the initial discharge to the Colorado River from discharge points 001, 002, 003, and 004 being allowed, the permittee shall demonstrate to the satisfaction of the Permits and Enforcement Section of the Division that the treated effluents are in compliance with COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 19. Permit No. CO -0042552 • f) Prior Demonstration of Compliance: (Cont., 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. Since it is believed that to pass WET testing, TDS removal is necessary and ammonia removal may be necessary, sufficient demonstration shall be made that the permittee has constructed and operated a treatment facility, and that adequate levels of 50 % WET acute toxicity, TDS, and total ammonia are achieved in the effluent from the discharges. Once these items have been demonstrated and reviewed by the Division, then a continued discharge will be allowed from the outfalls. 5. Whole Effluent Toxicity (WET) Testing: For this facility, acute WET testing is required for discharge points 001, 002, 003, and 004. 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, 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% COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 20. Permit No. C0-0042552 Instream Waste Concentration (IWC): (Continued) The flows and corresponding IWC for the appropriate discharge point are: Discharge Points Stream Low Flow (1E3) Facility Flow IWC 001 or 003 (Processing) and 001 (Disposal) 776 MGD 0.4464 MGD 0.1 % The IWC for this permit is 0.1 %, which represents a wastewater concentration of 0.1 X effluent to 99.9 X dilution water or receiving stream. 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 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 type of discharge, the receiving water classifications, and the ratio of the chronic stream low flow (30E3) to the facility discharge flows (for aquatic life class 2 classified segments). If the receiving water is classified aquatic life class 1 any discharge is required to have chronic WET testing in the permit. In this case, the classification for segment 1 is aquatic life class 1• therefore, chronic WET testing is required. 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 Conducting Whole COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 21. Permit No. C0-0042552 5. WWtole Effluent Toxicity (WET) Testinv,: (Continued) 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 in 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 22. Permit No. C0-0042552 B. 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. Antide¢radation: On September 21, 1989, an antidegradation assessment was made in which the Division made an initial review since the receiving stream (Colorado River) classifications include High Quality Class 2 and Aquatic Life Class 1 Cold Water. From this review, the Division concluded that the antidegradation presumption was overcome and that degradation of waters to the levels of the existing standards is allowed because the dilution ratio of the stream to the facility discharges was less than 100 to 1. 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, 002, 003, and 004 Parameter Measurement Frequency Sample Type Flow, MGD Oil and Grease, mg/1 I/ pH, s.u. Total Residual Chlorine, mg/1 Total Suspended Solids, mg/1 BOD5, mg/1 COD, mg/1 Total Ammonia, mg/1 as N Total Arsenic, mg/1 Total Dissolved Solids, mg/1 Total Zinc, mg/1 Dissolved Radium 226, pCi/1 Total Radium 226 and 228, pCi/1 Total Natural Uranium, mg/1 Whole Effluent Toxicity, Acute Whole Effluent Toxicity, Chronic Daily Daily Daily Weekly Weekly Weekly Weekly Weekly Weekly Monthly Weekly Weekly Weekly Weekly Quarterly; See Semiannually; See Instantaneous Visual Grab Grab Grab Grab Grab Grab Grab Grab Grab Grab Grab Grab Part I.B.3&4 Grab Part I.B.10 Composite COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 23. Permit No. CO -0042552 B. Monitoring and Reporting (Continued) 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 each of the two processing sites: Total Chloride Total Cyanide Total Nitrate Total Sulfate Total Recoverable Copper Total Mercury Total Recoverable Nickel Total Recoverable Silver 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 both processing sites in the one-time analysis 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 processing site. This data shall be submitted to the Permits and Enforcement Section within 45 days of the sampling dates of discharge. See Part I3.13 of the permit. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division .Rationale - Page 24. Permit No. CO -0042552 C. Additional Terms and Conditions 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 basins, but also to any other on-site facilities, including the recirculation pond, any storm water diversion/drainage ditches on site, 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. Office Permit Code Event Citation Due Date 90408 Prior Demonstration Part I.5.12 prior to discharge of Compliance 90508 Materials Containment Plan Part I.F 90 days after effective date of permit 90608 Inorganic/Radioactive Part I.5.13 within 45 days of the - One Time Analysis sample date (at the first instance of discharge) 90908 Salinity Report Part I.5.15 April 30, 1992 Don Holmer September 16, 1991 COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 25. Permit No. CO -0042552 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 Ouality Criteria 1972 ("Blue Book"). Wash., D.C.: U.S. Gov't Printing Office, 03-73-003, 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. VIII. CHANGES TO PERMIT AND RATIONALE FOLLOWING PUBLIC NOTICE M -K Ferguson Company submitted the only comment letters dated December 4, 1991 and December 26, 1991 regarding this public -noticed permit. The Division made some changes to the rationale and the permit, based in part upon these two comment letters, and upon other considerations. In the letter of December 4, 1991, M -K Ferguson Company indicated (in reference to the fuel storage discussion on page 7 of the rationale) that the oil storage capacity of 5000 gallons will certainly be changed when the sub -contractor is chosen. The quantity of storage is a function of how the individual sub -contractor wishes to operate. Once the final number of tanks and their volume has been determined, the permittee will request an amendment to the permit to reflect this change. Other permittee discussion in the December 4, 1991 letter included comments that discharge points 002 and 004 are emergency spillways in which no discharge from these two points is expected, that the stormwater outfall 005 is being taken out of service as part the Best Management Practices for this site, and that the only two outfalls that might be expected to discharge under normal conditions would be 001 and 003. Further, in reference to outfalls 001 and 003 (the discharges from the wastewater treatment plants), the permittee stated that "it is our current intent to assure that these two would not discharge simultaneously"; then the permittee requested a recalculation of the water quality standard -based permit limitations based upon a reduction in the facility flow in the mass balance equation. COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale --Page 26. Permit No. CO -0042552 VIII. CHANGES TO PERMIT AND RATIONALE FOLLOWING PUBLIC NOTICE (Continued) In the letter of December 26, 1991, the following comments were made. According to the permittee, the limits for total ammonia and total dissolved solids for this permit can be accomplished only through the use of advanced and expensive wastewater treatment technology. M -K Ferguson Company's initial review of available technologies concludes that the most cost-effective treatment system for meeting the proposed effluent limits consists of a vapor recompression evaporator backed up by ion exchange. To reduce the total volume of water requiring treatment, it is M -K Ferguson Company's intention to employ the following volume reduction measures to the extent possible: The use of slurry walls at both the New and Old Rifle sites. The implementation of the gravel to fines ratio protocol for determining that radium clean-up of soils is satisfactory. Further, in an effort to minimize capital expenditures, M -K Ferguson Company's current plans call for: - Transporting large quantities of water to a single central processing facility, taking advantage of available economies of scale. - Providing larger than usual retention basins, permitting the water to be processed at a lower rate in a smaller plant. In addition, M -K Ferguson Company indicated that when estimating the composition of wastewaters, they always present a worst case scenario, listing the highest recorded undiluted concentration of individual impurities. Once construction has started, wastewater data collected has always shown lower impurity levels than those listed in the permit application. M -K Ferguson Company also indicated that they are currently examining data from the New Rifle Processing site that gives a strong indication that the sub pile contamination is not as extensive as originally thought. If this proves to be correct, the permittee indicated that dewatering operations will be reduced to almost zero. A recent estimate shows that the vapor recompression/ion exchange system will cost in excess of five million dollars. According to the permittee, this is a particulary difficult financial burden for the project to bear, considering that water requiring this extensive processing will only be present for a total of six months. This period is the length of time during which sub pile excavation and groundwater dewatering will take place. The permittee feels that five million dollars is a very large sum of money to spend for something that will only be needed for a short time. For these reasons, M -K Ferguson Company again requested relief from the requirement of WET testing and COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 27. Permit No. C0-0042552 VIII. CHANGES TO PERMIT AND RATIONALE FOLLOWING PUBLIC NOTICE (Continued) limitations on the discharge of ammonia and total dissolved solids imposed by the public notice draft permit. The Water Quality Control Division has reviewed the preceeding comments from the permittee and has made some changes to the rationale and the permit for this facility, based in part upon these two comment letters and upon other considerations. Based upon a Division reevaluation of facility flows, a total facility flow (Q2) of 0.691 cfs, or 0.4464 MGD, was used for the WQS mass balance equation assessments. This new facility discharge flow 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. The flows from one WWTP discharge for both the Rifle processing sites and the Rifle disposal site WWTP discharge were included to establish a wasteload allocation for total ammonia for both facility permits. 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. This requirement has been included in page la of the permit. Based upon the new facility flow, the total ammonia limitation has been recalculated and now is 320 mg/1 as N for each of the four discharges at the Rifle processing sites. This will also be the total ammonia limitation for the two discharges at the Rifle disposal site. The discharge flows for outfalls 002 and 004 at the Rifle processing sites and 002 at the Rifle disposal site were not included in the WQS assessment, since these retention basin discharges 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 002 and 004 are not expected, except under conditions where the 10 -year, 24-hour precipitation event is exceeded. As indicated in the stormwater exemption requirements in the permit, 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.B.14 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.14.a) and b) of the permit. If discharges would be occurring from outfalls 002 or 004 which are not due to an exceedance of the 10 -year, 24-hour precipitation event, then the basis for the ammonia limitations in this permit would no longer be applicable, and the Division would need to reestablish ammonia limits that are also based upon the flows from outfalls 002 and 004. Since this permit was at public notice, the Whole Effluent Toxicity (WET) testing requirements have been revised in the Regulations for the State Discharge Permit System (6.1.0) (reference C). Thus, both the COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 28. Permit No. C0-0042552 .VIII. CHANGES TO PERMIT AND RATIONALE FOLLOWING PUBLIC NOTICE (Continued) permit and rationale language have been accordingly revised. The major change affecting this permit is that there is now a 50 % acute toxicity limit in the permit, and that the 50 % acute WET toxicity limit must be achieved, particularly with respect to the Total Dissolved Solids (TDS) concentration levels. The acute toxicity limit has been added to page la of the permit, and footnote o/ was also added to address acute toxicity. With respect to certain permit limits (including ammonia, arsenic, and zinc), per Section 6.9.7.(4)(a)(vi) of the "Regulations for the State Discharge Permit System", "if the acute toxicity limit is exceeded and the toxicity incident response determines that the toxicity results from a substance regulated by a numerical water quality standard -based permit limitation, that permit limitation shall be utilized for determining permit compliance rather than the acute toxcity limit." Thus, if toxicity occurring above the 50 % acute toxicity limit is found to be due to total ammonia, then the total ammonia limit of 320 mg/1 must be met and no further treatment for total ammonia is necessary. If acute toxicity in the facility discharge(s) is found to be due to ammonia concentrations which are within the permit limit of 320 mg/1, 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. The Division also determined from a reevaluation of the "Regulations for the State Discharge Permit System" that chronic WET testing is required for this facility, since the discharges go to a Class 1 Cold Water Aquatic Life stream. Thus, chronic WET testing is included as a permit requirement. With regard to the request from M -K Ferguson Company for relief from the requirement of WET testing and limitations on the discharge of ammonia and total dissolved solids imposed by the public notice draft permit, the changes in the ammonia limitations and in the WET requirements have been previously discussed. Some degree of relief may be possible with the permit limitation of 515 mg/1 for TDS once the Salinity Report has been submitted and reviewed by the Division. However, essentially no relief is possible for the TDS limitations with respect to the 50 % acute toxicity limit. The only apparent relief to the 50 % acute toxicity limit is the provision for an engineered design for instantaneous mixing for the discharge(s) from this facility as defined in Section 6.9.7(1)(a)(i) of the "Regulations for the State Discharge Permit System". Based upon changes of some water quality standards in the "Basic Standards and Methodologies for Surface Water", changes were made for potentially dissolved aluminum and total recoverable thallium in Table VI -2 of the rationale. In Table VI -3 of the rationale, the federal standards for total uranium were also included. On pages 1 and. la of COLORADO DEPARTMENT OF HEALTH, Water Quality Control Division Rationale - Page 29. Permit No. CO -0042552 VIII. CHANGES TO PERMIT AND RATIONALE FOLLOWING PUBLIC NOTICE (Continued) the permit, the expiration date was extended to December 31, 1996. On page lc of the permit, the mailing address for EPA was changed. The due date for the Salinity Report was changed to April 30, 1992. Don Holmer January 10, 1992 Permit No.: C0-0042552 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 former Old and New Rifle Processing Sites located in: the E 1/2, NE 1/4 of Sec. 16 and the W 1/2, NW 1/4 of Sec. 15, T6S, R93W (Old Rifle Processing Site), and the SE 1/4 of Sec. 18, T6S, R93W (New Rifle Processing Site), approximately 0.3 miles east of the center of Rifle on the south side of U.S. Highway 6 (Old Rifle site), and 2 miles west of the center of Rifle on the south side of U.S. Highway 6 (New Rifle site), as shown in figures 1 and 2 of the permit. to the Colorado River 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, December 31, 1996 Issued and Signed this 31st day of January, 1992 COLORADO DEPARTMENT OF HEALTH David Holm, Director Water Quality Control Division Code: i - 1 Date: 2 - 84 CERTIFiED LETIER T jo..P. ,, t 5— 3 7 DATE ICINE;_/3/ 9'r EFFEc: ; ► v'E. -• PART I Page la of 19 Permit No. C0-0042552 A. TERMS AND CONDITIONS 1. Effluent Limitations - Discharge Points 001, 002, 003, and 004 Beginning immediately and lasting through December 31, 1996, the permittee is authorized to discharge from outfall serial numbers: 001, the effluent pipe from the wastewater treatment plant at the Old Rifle Processing Site; 002, the emergency spillway structure from the wastewater retention basin at the Old Rifle Processing Site; 003, the effluent pipe from the wastewater treatment plant at the New Rifle Processing Site; and 004, the emergency spillway structure from the wastewater retention basin at the New Rifle Processing Site. All discharges are prior to mixing with the Colorado River, as shown in figures 1, 2, 3 and 4 of the permit. There shall be no simultaneous discharge from outfalls 001 and 003. 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. Effluent Parameter Discharge Limitations 30-Dav Avg a/ 7 -Day Avg / Daily Max Flow, MGD (Discharge Point 001) 0.360 N/A Report (Discharge Point 002) Report N/A Report (Discharge Point 003) 0.360 N/A Report (Discharge Point 004) 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 0.5 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 10.0 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 — 0.1% / 50% J Whole Effluent Toxicity, Chronic (through 12-31-1994) N/A N/A Report pH - (Standard Units) shall remain between 6.5 and 9.0 /. Oil and Grease shall not exceed 10 mg/1 g/ nor shall there be a visible sheen, see footnote fj. There shall be no discharge of floating solids. See Part I.D, for Footnotes Code: i - 2 Date: 1-84, revised 12-87, revised 12-88 PART I Page lb of 19 Permit No. C0-0042552 lb B. MONITORING REQUIREMENTS 1. Frequency and Sample Tuve - Outfalls 001, 002, 003, and 004 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 / Sample Type e/ Flow, MGD Daily Instantaneous Oil and Grease, mg/1 J Daily Visual pH, s.u. Daily Grab Total Suspended Solids, mg/1 Weekly Grab B0D5, mg/1 Weekly Grab COD, mg/1 Weekly Grab Total Residual Chlorine, mg/1 Weekly Grab Total Ammonia, mg/1 as N Weekly Grab Total Arsenic, mg/1 Weekly 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 Total Dissolved Solids, mg/1 g/ Monthly J Grab Whole Effluent Toxicity (WET) - Acute Quarterly Grab See Part I.B.3.&4. Whole Effluent Toxicity (WET) Chronic Semiannually (through 12-31-1994) See Part I.B.10. Composite 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 at the Old Rifle Processing Site; 002, the emergency spillway structure from the wastewater retention basin at the Old Rifle Processing Site; 003, the effluent pipe from the wastewater treatment plant at the New Rifle Processing Site; and 004, the emergency spillway structure from the wastewater retention basin at the New Rifle Processing Site. All four discharges are prior to mixing with the Colorado River, as shown in figures 1, 2, 3, and 4 of the permit. See Part I.D for footnotes. Code: i - 3 Date: 1-84, revised 2-87, revised 12-88 PART I Page lc of 19 Permit No. CO -0042552 lb 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, 002, 003, and 004 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, 002, 003, and 004 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 PART I Page ld of 19 Permit No. CO -0042552 O B. MONITORING REQUIREMENTS 4. Accelerated Testing - Outfalls 001, 002, 003, and 004 (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 0.1 % 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 - Outfalls 001, 002, 003, and 004 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 Revised 12/30/91 PART I Page le of 19 Permit No. CO -0042552 • B. MONITORING REQUIREMENTS 5. Preliminary Toxicity Investigation - Outfalls 001, 002, 003, 004 (Cont.) 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, 002, 003, and 004 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. If toxicity disappears during the Phase I TRE, the permittee shall submit written notification to that effect to the Division. The Revised 12/30/91 Part I Page if of 19 Permit No. CO -0042552 B. MONITORING REQUIREMENTS 6. Phase I TRE - Discharge Points 001, 002, 003, and 004 (Cont.) 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, 002, 003, and 004 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. Revised 12/30/91 Part I Page lg of 19 Permit No. C0-0042552 • B. MONITORING REQUIREMENTS 8. Control Program - Discharge Points 001, 002, 003, and 004 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, 002, 003, and 004 If WET is controlled through implementation of numeric limits for specific toxicants, through a control program eliminating toxicants from 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. Freouency and Sample Type - Chronic WET Testing Discharge Points 001, 002, 003, and 004 The monitoring frequency for chronic toxicity tests shall be once every six months on a January - June, July - December sequence, and cannot coincide with acute testing. Chronic tests will be static replacement tests using three composite effluent samples, each of which is to be composited for a minimum of eight hours. Chronic testing will be conducted with both Ceriodaphnia sp. and fathead minnows during the first year. During years two and three, if requested in writing by the permittee, the Division may grant relief from continued two species Revised 12/30/91 Part I Page lh of 19 Permit No. C0-0042552 • B. MONITORING REQUIREMENTS 10. Frequency and Sample Type - Chronic WET Testing - Discharge Points 001, 002, 003, and 004 (Continued) testing. Such relief shall be for continued testing with only that species which has demonstrated the greatest sensitivity during the first year of testing. The results shall be submitted on the Chronic 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 chronic toxicity test in general accordance with methods described in the Division guidance document entitled Guidelines for Conducting Whole Effluent Toxicity Tests. As general information, chronic toxicity occurs when there is a statistically significant difference in survival, growth or reproduction for either species. 11. Toxicity Reopener - Discharge Points 001, 002, 003, and 004 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. 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. 12. Prior Demonstration of Compliance - Discharge Points 001, 002, 003, and 004 Prior to the initial discharge to the Colorado River from discharge points 001, 002, 003, and 004 being allowed, the permittee shall demonstrate to the satisfaction of the Permits and Enforcement Section of the Division that the treated effluents are 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. In addition, prior to discharge sufficient Revised 12/30/91 Part I Page li of 19 Permit No. C0-0042552 Aft B. MONITORING REQUIREMENTS 12. Prior Demonstration of Compliance - Discharge Points 001, 002, 003, and 004 (Continued) demonstration shall be made that the permittee has constructed and operated an wastewater treatment facility, and that adequate levels of total ammonia and total dissolved solids are achieved in the effluent from the discharges. Once these items have been demonstrated and reviewed by the Division, then a continued discharge will be allowed. 13: 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 r (See Below) 001 or 002; 003 or 004 for all parameters Total Total Total Total Total Total Total Total Total Chloride Cyanide Nitrate Sulfate Recoverable Mercury Recoverable Recoverable Recoverable Copper Nickel Silver Vanadium Grab for all parameters 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, the permit may be amended to incorporate additional monitoring and limitations, as allowed under Part II.B.5 of this permit. Additional monitoring may also be required where the detection limit for a parameter is above the appropriate water quality standards. See Part I.C. for Footnotes. Part I Page lj of 19 Permit No. CO -0042552 B. MONITORING REQUIREMENTS 14. Storm Exemption - Facilities Permitted to Discharge - Discharge Points 002 and 004 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. 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 points 002 and/or 004, M -K Ferguson Company must demonstrate that the following water quality standard -based levels are attained: Total Ammonia, as N 320 mg/1 Total Arsenic 300 mg/1 Total Recoverable Zinc 79 mg/1 Total Radium 226 + 228 8700 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 -0042552 B. MONITORING REQUIREMENTS 15. Salinity (Total Dissolved Solids) Report Since the total salinity loading from the discharges is greater than one ton per day, the permittee is required to submit by April 30, 1992 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. The report shall include at least the following: (1) Description of the proposed construction. (2) Description of the quantity and salinity of the discharges. (3) Description of water rights, including diversion and consumptive use quantities. (4) Alternate plans that could reduce or eliminate salt discharge. Alternate plans shall include: (a) Description of alternative water supplies, including provisions for water reuse, if any. (b) Description of quantity of quality of proposed discharges. (c) Description of how salts removed from discharges shall be disposed of to prevent such salts from entering surface waters or ground water aquifers. (d) Costs of alternate plans in dollafs per ton of salt removed. PART I Page 1L of 19 Permit No. CO -0042552 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, diversion ditches, and/or 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 basins and ponds 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 continue to be practiced at the facility to ensure that no surface runoff occurs to surface waters, no pooling of waters occurs, no saturation of soils occurs beyond its ability to adsorb pollutants, and no adverse impact occurs with respect to groundwater concentration limits specified as part of the Remedial Action Plan. d) Manage the facility to prevent tailings material, contaminated water, spills, or other contaminants from entering any on-site drainage ditches that are tributary to the Colorado River. 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, drainage ditches, and any surface waters. PART I Pana 1fl,of 19 CO -0 42 2 OIMOMMGLE LOCATION vl • :.l1 s • R; REFERENCE : RIFLE, COLO. QUADRANGLE , USGS 1982 FIGURE 1 M -K Ferguson Company 0 SCALE OLD RIFLE PROCESSING SITE AND VICINITY • C• •`: i2 - • Q, • PART I Page 1n of 19 CO -0042552 1Jee • {••Yv .� '• . • •• e 7.‘""N tel` ••.. . 8 • •� I ��..Z.. ss-� I _ ' • . Pre fontalr• QUADRANGLE LOGi10n • ca<o1Aoo • i �`i• \l \ ;a C,..tt P • WESTEAN� ii- • -� RIO QRAF OC VCR -r - SAND` �T • �� or G,ikAd! 3 �.✓ i • 11"\----14 • saao its %ti L.`:. I. ss,s • •• _/ REFERENCE : RIFLE COLO. QUADRANGLE, USGS 1982 0 FIGURE 2 M -K Ferguson Company 2000 40 SCALE NEW RIFLE. PROCESSING SITE- AND VICINITY FEET I$ PART I Page lo of 19 CO -0042552 p - ,!q( • �t - ism ._e,Pc ■° [10.300 v. 0 m e rn n..." Yp -0 r 40- T as z ;go :2 - m a ^ K (iii ;l' • I' • p g • tD c - n H t 0 00 (D - � I -1i\• catW 0 0 i tr, 0 1 PART I Page 1p of 19 CO -0042552 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 - 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 - 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 aeasurement 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 D. FOOTNOTES PART I Page 3 of 19 VA e/ -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 between 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. J - 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. g/ - Where, based on a mimimum 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. J - TDS shall be sampled on a monthly basis. i/ - This parameter is subject to "Noncompliance Notification" requirements of Part II.A.3.(b)(v) of this permit. I/ - Procedure for determining settleable solids is contained in 40 CFR C 434.64. The method detection limit for measuring settleable solids under this part shall be 0.4 ml/1. J - Should a precipitation event occur which is greater than the 10 -year, 24-hour event, the permittee shall submit rain guage 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. 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. n/ The potentially dissolved metal fraction is defined in The Basic Standards and Methodologies for Surface Water 3.1.0 (SCCA 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 that 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 to: 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 ].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; 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. 8) 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 PART I Page 9 of 19 G. 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.3.2 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: 1 - 23 Date: 1-84, revised 12-88 PART II A. MANAGEMENT REQUIREMENTS Page 10 of 19 1. Change in Discharge 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, 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 new 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 I; 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 is 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 Recessary 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.4.3. 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 is this permit, including such accelerated or additional monitoring as aecessary 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 as 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 bnforcement 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 aecessary 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 ControlDivision, 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 Z6 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 teporting 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: (1) 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 S7, 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.B 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 1.3.3 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 la 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 (Oil 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: i - 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 II.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 feeas 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 STATE OF COLORADO Roy Romer, Governor Patti Shwayder, Acting Executive Director . Dedicated to protecting and improving the health and environment of the people of daaj"rJ,b': 4300 Cherry Creek Dr. S. Denver, Colorado 80222-1530 Phone (303) 692-2000 March 23, 1995 Laboratory Building 4210 E. 11th Avenue Denver, Colorado 80220-3716 (303) 691-4700 Mr. R.E. Lawrence, Project Director P. O. Box 9136 2309 Renard Place, S.E., #300 Albuquerque, NM 87119 CERTIFIED MAIL NO: P 319 472 471 MAR 2 7 19951 r z'. r 4-t LD COON(y .1876 lorado Department of Public Health and Environment RE: Amended Permit, Colorado Wastewater Discharge Permit System Number: CO -0042552, MK Ferguson Co., Garfield County Dear Mr. Lawrence: Enclosed please find a copy of the amended pages of your existing 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 including these changes. It is especially important to note the "EFFECTIVE DATE", not the "AMENDED DATE", located at the bottom of each amended page of your permit. It is illegal to discharge per the new conditions until the effective date. Please read the amended pages of the permit and if you have any questions contact this office at 692-3590. Sincerely, Robert J hukle, Chief Permits and Enforcement Section Water Quality Control Division xc: Permits Section, Environmental Protection Agency Regional Council of Government Local County Health Department District Engineer, Field Support Section, WQCD Derald Lang, Field Support Section, WQCD Enforcement Officer, Permits and Enforcement Section, WQCD Permit Drafters, Permits and Enforcement Section, WQCD Enclosure COLORADO DISCHARGE PERMIT SYSTEM (CDPS) AMENDMENT NO. 3 - RATIONALE M -K FERGUSON COMPANY URANIUM MILL TAILINGS REMEDIAL ACTION AT RIFLE OLD AND NEW URANIUM PROCESSING SITES FACILITY NUMBER: CO -0042552, GARFIELD COUNTY I. TYPE OF PERMIT.: Industrial - Amendment II. FACILITY INFORMATION: A. Facility Type and Fee Category: B. SIC Nos.: C. Legal Contact: D. Facility Contacts: E. Facility Location: Category 3, Subcategory 8 - Hardrock Mining: Milling with Discharge from 50,000 up to 999,999 gallons per day - Current fee $3,090/year per CRS 25-8-502 1629 - Reclanzation Projects Construction 1094 - Former Uranium Mill (Tailings Disposal) Mr. R.E. Lawrence, Project Director M.K. Ferguson Company P.O. Box 9136 2309 Renard Place, S.E., #300 Albuquerque, NM 87119 (800)+443-4379 or (505)+766-3227 Randy Withee, Project Site Manager M.K. Ferguson Company P.O. Box 151 24230 Highways 6 and 24 Rifle, CO 81650 (303)+625-4618 Charlie Spencer, Contruction Engineer Manager M.K. Ferguson Company P.O. Box 936 Albuquerque, NM 87119 (505)+845-5868 Sharon Arp U.S. Department of Energy P.O. Box 5400 5301 Central Avenue, N.E., Suite 1700 Albuquerque, NM 87115 (505)+845-5668 The Old Rifle Processing Site is located in the E 1/2, NE 1/4 of Sec. 16, and the W 1/2 of the NW 1/4 of Sec. 15, T6S, R93W, approximately 0.3 miles east of the center of Rifle on the south side of U.S. Highway 6. The New Rifle Processing Site is located in the SE 1/4 of Sec. 18, T6S, R93W, approximately 2 miles west of the center of Rifle on the south side of U.S. Highway 6. Both of the processing sites are shown in figures 1 and 2 of the permit. COLORADO DEPARTMENT OF PUBLIC HEALTH AND ENVIRONMENT, Water Quality Control Division Rationale, Amendment No. 3 - Page 2 Permit No. CO -0042552 F. Discharge Points and Discharge Flows: There are five discharge points for this permit. See pages 2 and 3 of the original rationale for details of these discharges, including the projected discharge flows. III. RECEIVING STREAM: Identification, Classification and Standards; and Receiving Water: No change from previous rationale; refer to original rationale. IV. PURPOSE OF AMENDMENT: In this amendment, discharge points 001 and 002 are being deleted. V. DISCUSSION OF AMENDMENT: This amendment request from the permittee, M -K Ferguson Company, for the Old Rfle processing site was received in a letter dated December 5, 1994. In this amendment, the permittee indicated the following information. The cleanup of all radioactive contaminated materials from the Old Rifle Processing Site has been completed as of November 21, 1994. The cleanup of this site included the removal of all FIDPE lined collection ditches, and the lined retention basin, which includes the permitted discharge points 001 and 002. Thus, this amendment request is for the removal of the Old Rifle Processing Site and its associated discharges (001,4, 001W, 001X, 002,4, 002W, and 002X) from this permit. In a recent conversation with the State UMTRA site project person for the Rifle facilities, Jim Hams has indicated that the previous retention basin and its associated oufall (002) at the Old Rifle Processing Site have been removed and backfilled. The associated pipes and drains have also been removed. The previous oufall from the wastewater treatment plant at the Old Rifle site (001) also no longer exists. Thus outfalls 001 and 002 were deleted from pages la through lj of the permit. Since this constitutes a significant facility change, public notice requirements are applicable. Don Holmer January 3, 1995 VL PUBLIC NOTICE COMMENTS AND CHANGES FOLLOWING PUBLIC NOTICE PERIOD: No comments were received regarding this amendment. In checking with the UMTRA staff at CDPHE, they indicated that they had no comments. There were no changes made to the amendment from what was in the public noticed -draft permit. Don Holmer March 8, 1995 Permit No.: C0-0042552 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 former Old and New Rifle Processing Sites located in: the E 1/2, NE 1/4 of Sec. 16 and the W 1/2, NW 1/4 of Sec. 15, T6S, R93W (Old Rifle Processing Site), and the SE 1/4 of Sec. 18, T6S, R93W (New Rifle Processing Site), approximately 0.3 miles east of the center of Rifle on the south side of U.S. Highway 6 (Old Rifle site), and 2 miles west of the center of Rifle on the south side of U.S. Highway 6 (New Rifle site), as shown in figures 1 and 2 of the permit. to the Colorado River 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, December 31, 1996 Issued and Signed this 31st day of January, 1992 COLORADO DEPARTMENT OF HEALTH David Holm, Director Water Quality Control Division Code: Date: 2 - 84 CERTIFIED LEITER at_Oa 5-3 � 7 DATE SIGNED 9 3 EFFECTIVE I i" t PEFtMIT„,44,7 Amended 11/25/92 Effective 01/01/93 Amended 05/12/94 Effective07/01/94 Amended03/23/95Effective05/01/95 PART I Page la of 19 Permit No. CO -0042552 A. TERMS AND CONDITIONS 1. Effluent Limitations - Discharge Points 003 and 004 Beginning immediately and lasting through October 31, 1996, the permittee is authorized to discharge from outfall serial numbers: 003, the effluent pipe from the wastewater treatment plant at the New Rifle Processing Site; and 004, the emergency spillway structure from the wastewater retention basin at the New Rifle Processing Site. Both discharges are prior to mixing with the Colorado River, as shown in figures 2 and 4 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. Effluent Parameter Discharge Limitations 30 -Day Avg a/ 7-Dav Avg a/ Daily Max c/ Flow, MGD (Discharge Point 003) 0.360 N/A Report (Discharge Point 004) Report N/A Report Total Suspended Solids, mg/1 20 N/A 30 BODS, mg/1 Report Report N/A COD, mg/I N/A N/A 500 Total Residual Chlorine, mg/I N/A N/A 0.5 Total Ammonia, mg/l as N 320 N/A Report Total Arsenic, mg/I 0.5 N/A 1.0 Total Zinc, mg/I 0.5 N/A 1.0 Dissolved Radium 226, pCi/1 3.0 N/A 10.0 Total Radium 226 and 228, pCi/1 10.0 N/A 30 Total Natural Uranium, mg/1 2.0 N/A 4.0 Total Dissolved Solids, mg/1 Report N/A 2100 Whole Effluent Toxicity, Acute N/A N/A IWC = 0.1% / 50% o/ Whole Effluent Toxicity, Chronic (through 12-31-1994) N/A N/A Report pH - (Standard Units) shall remain between 6.5 and 9.0 c/. Oil and Grease shall not exceed 10 mg/I c/ nor shall there be a visible sheen, see footnote f/. There shall be no discharge of floating solids. See Part I.C. for Footnotes Amended 11/25/92 Effective 01/01/93 Amended n 9 3/ 9 5 Effective 0 5/ Ql / 9 5 PART I Page lb of 19 Permit No. CO -0042552 B. MONITORING REQUIREMENTS 1. Frequency and Sample Type - Outfalls 003 and 004 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 d/ Flow, MGD Oil and Grease, mg/I f/ pH, s.u. Total Suspended Solids, mg/I BODS, mg/1 COD, mg/1 Total Residual Chlorine, mg/I 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 Whole Effluent Toxicity (WET) - Chronic Daily Daily Daily Weekly Weekly Weekly Weekly Weekly Weekly Weeldy Weekly Weeldy Weekly Monthly h/ Quarterly - See Part I.B.3 & 4 Quarterly - See Part I.B.10 Sample Type e/ Instantaneous Visual Grab Grab Grab Grab Grab Grab Grab Grab Grab Grab Grab Grab Grab Composite Sampling by the permittee for compliance with the monitoring requirements specified above shall be performed at the following locations: outfall serial number 003, the effluent pipe from the wastewater treatment plant at the New Rifle Processing Site; and 004, the emergency spillway structure from the wastewater retention basin at the New Rifle Processing Site. Both discharges are prior to mixing with the Colorado River, as shown in figures 2 and 4 of the permit. See Part I.C. for Footnotes Amended 03/23/TiSfective05/01/95 PART I Page lc of 19 Permit No. CO -0042552 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 WQCD-PE-B2 4300 Cherry Creek Drive South Denver, Colorado 80222-1530 U.S. Environmental Protection Agency Denver Place 999 18th Street, Suite 500 Denver, CO 80202-2405 Attention: Water Management Division Compliance Branch 8WM-C 3. Frequency and Sample Type - Acute WET Testing - Discharge Points 003 and 004 The monitoring frequency for acute WET tests shall be quarterly, commencing with the first full calendar quarter following the permit effective date. 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 003 and 004 If an individual toxicity test shows toxicity at any concentration less than or equal to the Instream Waste Concentration (IWC) of 0.1 %, 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. Amended 01/ 9 3/ g 5 Effective n s/ n l/95 PART I Page Id of 19 Permit No. CO -0042552 B. MONITORING REQUIREMENTS 4. Accelerated Testing - Discharge Points 003 and 004 (Cont.) Within 7 days of becoming aware of the toxicity, the permittee shall then begin 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 permittee 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 003 and 004 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 permittee 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 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. Amended03/2/95 Effective 05/x1 /95 PART I Page le of 19 Permit No. CO -0042552 B. MONITORING REQUIREMENTS 6. Phase I TRE - Discharge Points 003 and 004 The Phase I TRE performed by the permittee shall be in general accordance with Methods for Aquatic Toxicity Identification 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 approval by 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 a Phase II TRE. 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 no acute toxicity is found to exist, the permittee shall resume normal quarterly testing. 7. Phase II TRE - Discharge Points 003 and 004 A plan for a Phase H 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 11 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. Amended()3/73/g5 Effective .0 /f11 /95 PART I Page if of 19 Permit No. CO -0042552 B. MONITORING REQUIREMENTS 7. Phase II TRE - Discharge Points 003 and 004 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 11 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. 8. Control Program - Discharge Points 003 and 004 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 003 and 004 If WET is controlled through implementation of numeric limits for specific toxicants, through a control program eliminating toxicants from the waste stream, or through the implementation of treatment processes, or if WET disappears and Division required accelerated testing demonstrate the continued absence of toxicity, the toxicity incident response shall be considered closed and normally 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. Amended -n/2 3/ 9 5 Effective 0 5/ n1 /95 Part I Page lh of 19 Permit No. CO -0042552 B. MONITORING REQUIREMENTS 12. Prior Demonstration of Compliance - Discharge Points 003 and 004 Prior to the initial discharge to the Colorado River from discharge points 003 and 004 being allowed, the permittee shall demonstrate to the satisfaction of the Permits and Enforcement Section of the Division that the treated effluents are 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. In addition, prior to discharge sufficient demonstration shall be made that the permittee has constructed and operated an ammonia treatment facility, and that an adequate level of total ammonia is achieved in the effluent from the discharges. Once these items have been demonstrated and reviewed by the Division, then a continued discharge will be allowed. 13. 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 (See Below) Total Chloride Total Cyanide Total Nitrate Total Sulfate Total Recoverable Copper Total Mercury Total Recoverable Nickel Total Recoverable Silver Total Recoverable Vanadium Discharge Points Sample Type e/ 003 or 004 Grab for for all parameters all parameters 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, the permit may be amended to incorporate additional monitoring and limitations, as allowed under Part II.B.5 of this permit. Additional monitoring may also be required where the detection limit for a parameter is above the appropriate water quality standards. See Part I.C. for Footnotes. Amended 0 3/ 7 3/ 9 5 Effective fl 5/ 01 /95 Part I Page li of 19 Permit No. CO -0042552 B. MONITORING REQUIREMENTS 14. Storm Exemption - Facilities Permitted to Discharge - Discharge Point 004 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 will be 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 minimi the amount of overflow. All data/documentation required by this section which can not be reported on applicable discharge monitoring report forms (DMA'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 points 002 and/or 004, M -K Ferguson Company must demonstrate that the following water quality standard -based levels are attained: Total Ammonia, as N Total Arsenic Total Recoverable Zinc Total Radium 226 + 228 Natural Total Uranium 160 mg/1 150 mg/1 39 mg/1 4200 pCi/1 48 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. Amended0 3/ 2 3/ 9 5 Effective 0 5/ 0 1 / 9 5 (Note: as part of Amendment No. 3, page lj was incorporated into page li; thus page lj is now deleted from the permit.)