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HomeMy WebLinkAboutDRC-2011-007509 - 0901a0688027eb1cDenison Mines (USA) Corp. 105017th Street, Suite 950 Denver, CO 80265 USA Tel : 303 628-7798 Fax: 303 389-4125 www.denisonmines.com October 17, 2011 VIA E-MAIL AND OVERNIGHT DELIVERY Mr. Rusty Lundberg Utah Department of Environmental Quality 195 North 1950 West P.O. Box 144850 Salt Lake City, UT 84114-4850 Re: Denison Mines (USA) Corporation ("DUSA") White Mesa Mill Facility DRC Inspection Results: Storm Water Best Management Practices Plan ("SWBMPP"), Ground Water Module 65, October 9, 2010, Utah Ground Water Discharge Permit No. UGW370004: DRC Request for Information and Confirmatory Action Letter Dear Mr. Lundberg: This letter transmits Denison Mines (USA) Corp's ("DUSA's") responses to the DRC Request for Information and Confirmatory Action Letter, dated September 1, 2011. We have re-quoted each RFI and Confirmatory Action item and provided below, specific responses to each request as required by the DRC September 1, 2011 letter. DRC Request for Information: 1. DRC requests information regarding updates to ttie plans/inspections to provide inspections according to frequencies required by ttie Storm Water Best Management Practices Plan (SWBI\PP). For example, the SWBMPP requires a weekly inspection of ttie diversion ditches; however, they are conducted monthly. Failure to provide these inspections in conformance with the SWBMPP or modify the SWBMPP is a violation of the Part 1. D.1 Oof the Groundwater Permit. DUSA Response: Per the telephone conversation between DRC and DUSA on September 21, 2011, the diversion ditch inspections will continue to be conducted monthly. This inspection frequency continues to be appropriate for identifying the types of slow-developing changes that may occur in the diversion ditches. The Storm Water Best Management Practices Plan (SWBMPP) has been revised to reflect monthly inspections of the diversion ditches. A revised SWBMPP has been enclosed in Attachment A. 2. DRC requests information regarding the inspection procedures for reagent storage tanks (including intermediate process tanks, e.g. Pregnant Liquors) which are installed on-grade (on-grade refers to tank installations where the tank bottom is in contact with the ground) to insure that the structural integrity of the tank bottom is acceptable/appropriate. Cathode protection for on grade tanks is prescribed in Part I. D.10(a) of the Groundwater Permit. N:\lnspections and NOVs\Stormwater lnspections\SW Inspection 2010 and 2011 RAI\10.15.11 Responses to 09.01.11 Stormwaterlnspectionletter\10.17.11ResponsetoDEQ09.01.11ltr.doc Letter to Mr. Rusty Lundberg Storm Water Inspection RFI/Confirmatory Action Response October 17, 2011 Page 2 DUSA Response: Cathodic protection per se is not prescribed in part I.D.10(a) of the GWDP. Part .D.10(a) refers to non-specific general requirements. However, DUSA has agreed to modify tanks for consistency with the general requirements where appropriate as discussed below. Per email correspondence from DRC on September 26, 2011, DUSA understands that DRC requires cathodic protection on tanks whose bases are in contact with the ground surface. That is, DRC does not require tanks which are on concrete pedestals, whether diked or not, to have cathodic protection. Based on the correspondence and the inspection report, DUSA has completed an inspection of all on-grade tanks to determine the necessity of cathodic protection. The following results of the tank inspection were noted: • There are three kerosene tanks. The east tank is on a concrete pedestal. The two west tanks are placed on-grade, on the ground surface. • The ammonia tanks are on concrete pedestals. • The sulfuric acid tank is on a concrete pedestal. • The exterior VPL and water tank by the Old Decontamination Pad ("ODP") are on concrete pedestals. Dirt had filled in the area around the pedestals and, at the time of the 2010 inspection, gave the mistaken impression that the tanks were on-grade. DUSA had discussed with DRC the installation of cathodic protection on reagent or fuel tanks that were not on pedestals, saddles, or dikes, specifically the kerosene tanks. DUSA has since decided that it would be more prudent to construct comparable concrete bases (pedestals) for the remaining kerosene tanks, as are in place on the other flat bottomed tanks. The west two kerosene tanks will be modified by being raised for pouring of tank pedestals, and replaced after concrete for the pedestals is set and suitable for tank setting. Construction of these modifications will be complete by the end of December 2011. Based on DRC's email of September 26, 2011, tanks with concrete foundations, with or without dikes, will not be required to have cathodic protection and will be considered to be compliant with EPA requirements for tanks where inspection procedures are not practicable. The pedestals of the exterior VPL and water tank by the ODP were cleared of soil buildup during October, 2011. Photographs documenting the removal of the loose soil are provided in Attachment B. 3. DRC requests an outline of a plant process for internal notification and documentation of the clean up of small quantity spills (less than reportable quantities). Per the 2010 inspection, it was observed that a fuel spill had occurred at the fuel tank area and had not been cleaned up and there did not appear to be a process to identify, document, or clean up such spills. Failure to provide/maintain such a process is in non-conformance with the White Mesa Mill, June, 2008 SWBMPP, Part 4.2.1. DUSA Response: DUSA has implanted an internal notification process for small quantity spills (less than reportable quantities), with the following steps: 1) Mill environmental personnel will fill out on the daily inspection form observations of spills of reagent chemicals of any size. The form will be amended to add spaces for this item. 2) In addition, all Mill employees will be trained to advise Mill environmental personnel of any spills that they observe during the day, and these will also be noted in the daily inspection form. DENISO MINES Letter to Mr. Rusty Lundberg Storm Water Inspection RFI/Confirmatory Action Response October 17, 2011 Pages 3) If the spill is of a reportable quantity, environmental personnel will follow the procedures in the Mill's SWBMPP plan. 4) For spills smaller than reportable quantities, the environmental inspector will record information regarding the spill, and the nature and type of cleanup, on the form. 5) This information on the inspection form will be added to a database maintained at the Mill. The database will be updated and maintained on site indefinitely. Cards are maintained for no longer than one year. 4. DRC requests that DUSA review the White Mesa Mill SPCC Plan (dated June, 2008) to insure that all tanks included under the current facility Spill Prevention Countermeasure and Control (SPCC) plan meet current requirements of current EPA rules (40 CFR 112). Specifically, any additional tanks, including non-PCB containing tanks, should be evaluated and included under the oil storage inventory and inspection protocols, where required. This RFI is required in order to insure that procedures and policies at the mill are in accordance with current requirements. DUSA Response: The Mill has historically not been considered to fall within the rules set out in 40 CFR 112, for the reasons discussed below; therefore DUSA does not believe that the specific requirements of those regulations apply to the site. However, as a matter of prudency and good operating practice, DUSA will review those regulations to determine whether or not any modifications to the SPCC would be appropriate for the Mill. Denison will submit the results of its review under separate cover within 30 days from the date of this letter. SPCC requirements apply to "[a]ny owner or operator of a non-transportation-related onshore ... facility, using, or consuming oil and oil products, which due to its location, could reasonably be expected to discharge oil in quantities that may be harmful...into or upon the navigable waters of the United States... or that may affect natural resources belonging to, appertaining to, or under the exclusive management authority of the United States..." 40 CFR 112.1(b). SPCC rules allow the owner to consider whether due to the geographical and location aspects of the facility (such as proximity to navigable waters or adjoining shorelines, land contour, drainage, etc.), it could not reasonably be expected to discharge oil in harmful quantities to a navigable water. The Mill was constructed with an overall grade and diversion ditch system designed to channel any non-recovered portion of any material spill to the tailings management system. The land contour and drainage characteristics of the site are permanent geographical aspects of the site which do not involve man-made features or devices which could fail. These features, along with the Mill's relative distance from any navigable water, or means to reach navigable water, prevent any potential discharge of oil at the Mill site from reaching navigable waters. Upon review of our files DUSA has determined that the Mill's SPCC plan was originally developed during the period when the Mill was operated by Umetco Minerals Corp., a subsidiary of Union Carbide Corporation. As with all Union Carbide operating facilities, as a matter of Union Carbide corporate policy. Union Carbide required Umetco to prepare and maintain an SPCC plan for the Mill. That is, we understand that the Mill's SPCC plan was implemented voluntarily by the Mill operator as manner of prudent operating practices, and not as a result of a regulatory requirement. DUSA also believes that it is prudent to maintain and comply with the SPCC plan. As stated in the Introduction to the Mill's SWBPP, "(a)lthough the Mill, by design, cannot directly impact stormwater, surface water, or groundwater, the Mill implements these practices in a good faith effort to minimize all sources of pollution at the site." Therefore, based on the Mill site's permanent characteristics as described above, DUSA does not believe that the specific requirements of the Clean Water Act are applicable to the Mill site. However, as mentioned above. DENISO MINES Letter to Mr. Rusty Lundberg Storm Water Inspection RFI/Confirmatory Action Response October 17, 2011 Page 4 DUSA will review the regulations at 40 CFR 112 to determine whether or not any modifications to the SPCC plan would be appropriate for the Mill. 5. DRC requests that DUSA seal the interior drain(s) in the vehicle maintenance areas to prevent interior spills from draining to outdoor, uncovered areas/catchments. This is specified in the facility SWBMPP and is considered a "best management practice" to minimize the quantity of contaminated material. The open drain(s) not in conformance with the SWBMPP part 4.3.1, second bullet "clean up spills promptly, don't let minor spills spread." DUSA Response: Per Denison's communications with DRC on September 21 and 22, 2011, DRC will not require sealing of the interior drain(s) in the vehicle maintenance areas if DUSA provides a description of the spill management practices in this area demonstrating that the practices do not increase the volume of contaminated water sent to the oil/water separator. The maintenance area spill management practices and operation of the oil/water separator are described below. Spills in the Maintenance Shop are initially managed by on-the-spot cleanup of the majority of the spilled volume with clay or sorbents. The sorbent media used for spill pickup is transferred to a disposal area in tailings Cell 3. Following initial spill pickup, the floor is washed to the inside oil/water sump. The sumps operate as follows. The outside wash bay sump oil water separator on the north side of the Shop collects wash water from washdown of mobile equipment, along with building roof runoff. The separator has two sections separated by an overflow weir. The smaller section (sump), beyond the weir, allows mud to settle. Mud collected in this sump is removed approximately annually or as operations and maintenance allows, and transferred to Cell 3. The overflow from the overflow sump is piped through an underground line to a second stage oil/water separator inside the building. This separator also has an overflow weir and sump for collection of entrained solids. The overflow sump has not required removal of solids to date, but is monitored, as is the outside overflow sump, and can be emptied as required. Overflow solutions from the separator are transferred to the CCD tailings sump from which they are pumped to one of the tailings cell as directed by operations management. The above practice does not increase the volume of contaminated water to the oil/water separator or the tailings, and does not combine contaminated water with clean water. Regardless of the configuration, all overflow water and all removed solids from both the inside and outside separators are transferred to the tailings system. Sealing the floor drain valves and management of water from inside the Shop would not reduce the volume ofwater to the tailings system, since all the water, inside or outside, would still be transferred to tailings system. 6. DRC requests that DUSA insure that the clean water tank valve is sealed properly. Per the 2010 storm water inspection, it was noted that this valve was leaking and was creating ponded water areas in unlined ditch/soil areas. This is not in conformance with Section 4.1.4 of the SWBMPP which states, "Areas requiring maintenance or repair, such as excessive vegetative growth, channel erosion or pooling of surface waterrunoff, will be report[ed] to site management and maintenance departments for necessary action to repair damage or perform reconstruction in order for the control feature to perform as intended." DENISO MINES Letter to Mr. Rusty Lundberg Storm Water Inspection RFI/Confirmatory Action Response October 17, 2011 Page 5 DUSA Response: The clean water tank valve that was noted as leaking during the inspection is an overflow valve. The overflow noted was not due to inadequate maintenance of any valve. The flow which DRC observed was, in fact, operating properly to drain an overflow of clean water makeup from the top of the tank to the drainage system. In a tank overfill situation, the overflow system, by design, allows flow of excess water until the overflow rate reduces to a near trickle prior to the cessation of flow when the tank level is stabilized. What the DRC inspector observed during the 2010 inspection was proper normal operation of the overflow loop near the end of the overflow, not a malfunctioning valve. Moreover, the area below the clean water tank is graded such that when the overflow valve releases clean water, the water will drain to Cell 1 so that no significant ponding will result from this design. DRC Confirmatory Action: 1. DUSA has violated Part l.D.ll of the Groundwater Permit by failing to manage drums containing alternate feed material (located outside of the feedstock management area) in compliance with the required performance standards. a. Feedstock material was not stored in water tight containers, b. Feedstock material was not stored on a hardened engineered surface or asphalt or concrete, c. Feedstock material was not stored in a designed and approved storage area (by the Co-Executive Secretary), orother approved area. d. DRC observed open and degraded containers containing feedstock material on soil and located outside of the feedstock management area. DUSA Response: Based on communications with DRC on September 21 and September 22, 2011, Denison has completed the following modifications to the Alternate Feed area: a) Denison disagrees with DRC's statement that feedstock material was not stored in watertight containers. All alternate feed materials have been and will continue to be stored in water-tight drums or in overpack drums. Denison considers intact shipping drums, with no apparent leakage, as well as overpack drums, both to be water tight containers. Denison disagrees that containers that may be "degraded" are not watertight, when no leakage is present. However, one drum with perforations was staged in the alternate feed area prior to processing As a result, regardless of the type of drum, all drums in the Alternate Feed area are now placed on the new concrete pad described in item b), below, when not in the drum rack. b) A concrete pad has been installed in the alternate feed area. The design of the concrete pad was approved by DRC prior to the installation (see the letter dated September 30, 2011 in Attachment C). Photographic documentation and as-built drawings of the concrete storage pad, whose construction was completed on October 14, 2011, are included in Attachment D c) See response to item b), above. d) See response to item b), above. 2. DUSA has violated Part I.D. 10 of the Groundwater Permit by failing to replace/repair concrete in the secondary containment of the Caustic Soda Tank. DENISO MINES Letterto Mr. Rusty Lundberg Storm Water Inspection RFI/Confirmatory Action Response October 17, 2011 Page 6 DUSA Response: The secondary containment area for the Caustic Soda tanks has been repaired during October 2011, as shown in the photographs included in Attachment E. As discussed during communications between DRC and DUSA on September 21 and 22, 2011, DUSA plans further upgrades to the caustic soda area during a future maintenance outage in 2012, at which time the caustic tanks and secondary containment will be reconfigured. However, per communications between DRC and DUSA on September 21 and 22, 2011, DRC agreed to consider the caustic soda area in compliance with Part l.D.ll based on the repairs completed on October 14, 2011. 3. DUSA has violated Part I.D. 10 of the Groundwater Permit by failing to repair cracks in the secondary containment area for the soda ash tanks. DUSA Response: The secondary containment area for the soda ash tanks has been repaired during the first week of October 2011, as shown in the photographs included in Attachment F. Per communications between DRC and DUSA on September 21 and 22, 2011 DRC agreed to consider the caustic soda area in compliance with Part l.D.ll once the repairs are completed. Please contact me if you have any questions or require any further information. Yours very truly, DENISON MINES (USA) CORP. Jo Ann Tischler Director, Compliance and Permitting cc: David C. Frydenlund Harold R. Roberts David E. Turk K. Weinel Central files DENISOl MINES STORMWATER BEST MANGEMENT PRACTICES PLAN for White Mesa Uranium Mill 6425 South Highway 191 P.O. Box 809 Blanding, Utah »October2011 Prepared by: Denison Mines (USA) Corp. 1050 17th Street, Suite 950 Denver, CO 80265 TABLE OF CONTENTS 1.0 INTRODUCTION/PURPOSE. 2.0 SCOPE. 3.0 RESPONSIBILFTY 3 4.0 BEST MANAGEMENT PRACTICES 4 4.1 General Management Practices Applicable to All Areas 4 4.1.1 Keep Potential Pollutants from Contact with Soil, and Surface Water: 4 4.1.2 Keep Potential Pollutants from Contact with Precipitation 4 4.1.3 Keep Paved Areas from Becoming Pollutant Sources 4 4.1.4 Inspectton and Maintenance of Diversion Ditches and Drainage Channels within the Process and Reagent Storage Area 4 4.1.5 Recycle Fluids Whenever Possible: 4 4.2 Management Practices for Process and Laboratory Areas 5 4.2.1 Clean Up Spills Properly 5 4.2.2 Protect Materials Stored Outdoors 5 4.2.3 Management 5 4.2.4 Materials Management 5 4.3 Management Practices for Maintenance Activities 6 4.3.1 Keep a Clean Dry Shop 6 4.3.2 Manage Vehicle Fluids •. 6 4.3.3 Use Conirols During Paint Removal 6 4.3.4 Use Controls During Paint Application and Cleanup 6 4.4 Management Practices for Ore Pad, Tailings Area, and Heavy Equipment.. 7 4.4.1 Wash Down Vehicles and Equipment in Proper Areas 7 4.4.2 Manage Stockpiies to Prevent Windbome Contamination 7 4.4.3 Keep Earthmoving Activities from Becoming Pollutant Sources 7 Figures figure 1: White Mesa Mill Site Layout 17i6: /^igure2: White Mesa Mill Site Drainage Basins „ ._ „.i81r7 /•igure 3: Denison Mines (USA) Corp.- White Mesa Mill Management Organization Chart 2018 figure 4: Denison Mines (USA) Corp. - Corporate Management Organizational Chart 21i9 Tables Field Code Changed Field Code Changed Field Code Changed Field Code Changed JABLE 1.0: TABLE 2.0: TABLE 3.0: TABLE 4.0: TABLE 5.0: TABLE 6.0: Appendices White Mesa Mill Management Personnel Responsible for Implementing This BMPP 9 , - | Field Code Changed REAGENT YARD LIST 10 fpieldCodecSngS^ LABORATORY CHEMICAL INVENTORY LIST 1 12ii . REAGENT YARD/SMALL QUANTITY CHEMICALS LIST 1 .........^ .............13i3 Field Code Changed I-AGHNT YARD/BULK CHEMICALS LIST 1..... ...1413 [ Field Code Chang(^ PETROLEUM PRODUCTS AND SOLVENTS LIST 1 1514 [Field Code Changed Field Code Changed Appendix 1 White Mesa Mill Spill Prevention, Control, and Countermeasures Plan Appendix 2 White Mesa Mill Emergency Response Plan Best Management Practices Plan Revision 1.34: Juno 12. 2008October 2011 1.0 INTRODUCTION/PURPOSE Denison Mines (USA) Corp. ("DUSA") operates the White Mesa Uranium Mill ("the Mill) in Blanding, Utah. The Mill is a net water consumer, and is a zero-discharge facility with respect to water effluents. That is, no water leaves the Mill site because the Mill has: • no outfalls to public stormwater systems, • no surface runoff to public stormwater systems, • no discharges to publicly owned treatment works ("POTWs"), and • no discharges to surface water bodies. The State of Utah issued Groundwater Discharge Permit No. UGW370004 to DUSA on March 8, 2005. As a part of compliance with the Permit, DUSA is required to submit a Stormwater Best Management Practices Plan ("BMPP") to the Executive Secretary of the Division of Radiation Control, Utah Department of Environmental Quality. This BMPP presents operational and management practices to minimize or prevent spills of chemicals or hazardous materials, which could result in contaminated surface water effluents potentially impacting surface waters or ground waters through runoff or discharge connections to stormwater or surface water drainage routes. Although the Mill, by design, caiinot directly impact stormwater, surface water, or groundwater, the Mill implements these practices in a good faith effort to minimize all sources of pollution at the site. Page 1 Best Management Practices Plan Revision 1.34: Juno 12. 2008October2011 2.0 SCOPE This BMPP identifies practices to prevent spills of chemicals and hazardous materials used in process operations, laboratory operations, and maintenance activities, and minimize spread of particulates from stockpiles and tailings management areas at the Mill. Storage of ores and altemate feeds on the ore pad, and containment of tailings in the Mill tailings impoundment system are not considered "spills" for the purposes of this BMPP. The Mill site was constructed with an overall grade and diversion ditch system designed to channel all surface runoff, including precipitation equivalent to a Probable Maximum Precipitation/Probable Maximum Flood ("PMP/PMF") storm event, to the tailings management system. In addition, Mill tailings, all other process effluents, all solid waste and debris (except used oil and recyclable materials), and spilled materials that cannot be recovered for reuse are transferred to one or more of the tailings cells in accordance with the Mill's NRC license conditions. All ofthe process and laboratory building sinks, sumps, and floor drains are tied to the transfer lines to the tailings impoundments. A site map of the Mill is provided in Figure I.A sketch of the site drainage basins is provided in Figure 2. As a result, unlike other industrial facilities, whose spill management programs focus on minimizing the introduction of chemical and solid waste and wastewater into the process sewers and storm drains, the Mill is permitted by NRC license to manage some spills via draining or wash_down to the process sewers, and ultimately the tailings system. However, as good environmental management practice, the Mill attempts to minimize: 1. the number and size of material spills, and 2. the amount of unrecovered spilled material and wash_water that enters the process sewers after a spill cleanup. Section 4.0 itemizes the practices in place at the Mill to meet these objectives. Requirements and methods for management, recordkeeping, and documentation of hazardous material spills are addressed in the DUSA White Mesa Mill Spill Prevention, Control and Countermeasures ("SPCC") Plan Revised February, 2007, the Emergency Response Plan ("ERP"), also revised in February, 2007, and the housekeeping procedures incorporated in the White Mesa Mill Standard Operating Procedures ("SOPs"). The latest revisions ofthe SPCC plan and the ERP are provided in their entirety in Appendices 1 and 2, respectively. Page 2 Best Management Practices Plan Revision 1.34: Juno 12. 2008October 2011 3.0 RESPONSIBILITY All Mill personnel are responsible for implementation of the practices in this BMPP. DUSA White Mesa Mill management is responsible for providing the facilities or equipment necessary to implement the practices in this BMPP. The Mill Management Organization is presented in Figure 3. The DUSA Corporate Management Organization is presented in Figure 4. An updated spill prevention and control notification list is provided in Table 1. Page 3 Best Management Practices Plan Revision 1.34: June 12.2008October 2011 4.0 BEST MANAGEMENT PRACTICES A summary list and inventory of all liquid and solid materials managed at the Mill is provided in Tables 2 through 5. 4.1 General Management Practices Applicable to All Areas 4.1.1 Keep Potential Pollutants from Contact with Soil, and Surface Water: • Store hazardous materials and other potential pollutants in appropriate containers. • Label the containers. • Keep the containers covered when not in use. 4.1.2 Keep Potential Pollutants from Contact with Precipitation • Store bulk materials in covered tanks or drums. • Store jars, bottle, or similar small containers in buildings or under covered areas. • Replace or repair broken dumpsters and bins. • Keep dumpster lids and large container covers closed when not in use (to keep precipitation out). 4.1.3 Keep Paved Areas from Becoming Pollutant Sources • Sweep paved areas regularly, and dispose of debris in the solid waste dumpsters or tailings area as appropriate. 4.1.4 Inspection and Maintenance of Diversion Ditches and Drainage Channels within the Process and Reagent Storage Area • Diversion ditches, drainage channels and surface water control structures in and around the Mill area will be inspected at least wocldy monthly in accordance with the regularly scheduled inspections required by Groundwater Discharge Permit No. UGW370004, and Bby product Materials License #UT1900479. Areas requiring maintenance or repair, such as excessive vegetative growth, channel erosion or pooling of surface water runoff, will be reported to site management and maintenance departments for necessary action to repair damage or perform reconstruction in order for the control feature to perform as intended. Status of maintenance or repairs will be documented during follow up inspections and additional action taken if necessary. 4.1.5 Recycle Fluids Whenever Possible: • When possible, select automotive fluids, solvents, and cleaners that can be recycled or reclaimed • When possible, select consumable materials from suppliers who will reclaim empty containers. • Keep spent fluids in properly labeled, covered containers until they are picked up for recycle or transferred to the tailings area for disposal. Page 4 Best Management Practices Plan Revision 1.34: Juno 12. 2008October 2011 4.2 Management Practices for Process and Laboratory Areas 4.2.1 Clean Up Spills Properly • Clean up spills with dry cleanup methods (absorbents, sweeping, collection drums) instead of water whenever possible. • Clean spills of stored reagents or other chemicals immediately after discovery. • (Groundwater Discharge Permit No. UGW370004, Section LDLD.glO.c.) • Recover and re-use spilled material whenever possible. • Keep supplies of rags, sorbent materials (such as cat litter), spill collection drums, and personnel protective equipment ("PPE") near the areas where they may be needed for spill response. • If spills must be washed down, use the minimum amount of water needed for effective cleanup. 4.2.2 Protect Materials Stored Outdoors • If drummed feeds or products must be stored outdoors, store them in covered or diked areas when possible. • If drummed chernicals must be stored outdoors, store them in covered or diked areas when possible. • Make sure drums and containers stored outdoors are in good condition and secured against wind or leakage. Place any damaged containers into an overpack drum or second container. 4.2.3 Management • When possible, recycle and reuse water from flushing and pressure testing equipment^When possible, wipe down the outsides of containers instead of rinsing them off in the.sink. • When possible, wipe down counters and work surfaces instead of hosing or rinsing them.off to sinks and drain 4.2.4 Materials Management • Purchase and inventory the smallest amount of laboratory reagent necessary. • Do not stock more of a reagent than will be used up before its expiration date. • -All new construction of reagent storage facilities will include secondary containment.which shall control and prevent any contact of spilled reagents, or otherwise released • reagent or product, with the ground surface. (Groundwater Discharge Permit No. • UGW370004, Section I.D.3.eg.) Pages Best Management Practices Plan Revision 1.34: June 12. 2008October 2011 4.3 Management Practices for Maintenance Activities 4.3.1 Keep a Clean Dry Shop • Sweep or vacuum shop floors regularly. • Designate specific areas indoors for parts cleaning, and use cleaners and solvents only in those areas. • Clean up spills promptly. Don't let minor spills spread. • Keep supplies of rags, collection containers, and sorbent material near each work area where they are needed. • Store bulk fluids, waste fluids, and batteries in an area with secondary containment (double drum, drip pan) to capture leakage and contain spills. 4.3.2 Manage Vehicle Fluids • Drain fluids from leaking or wrecked/damaged vehicles and equipment as soon as possible. Use drip pans or plastic tarps to prevent spillage and spread of fluids. • Promptly contain and transfer drained fluids to appropriate storage area for reuse, recycle, or disposal. • Recycle automotive fluids, if possible, when their useful life is finished. 4.3.3 Use Controls During Paint Removal • Use drop cloths and sheeting to prevent windbome contamination from paint chips and sandblasting dust. • Collect, contain, and transfer, as soon as possible, accumulated dusts and paint chips to a disposal location in the tailings area authorized to accept waste materials from maintenance or constmction activities. 4.3.4 Use Controls During Paint Application and Cleanup • Mix and use the right amount of paint for the job. Use up one container before opening a second one. • Recycle or reuse leftover paint whenever possible. • Never clean brushes or rinse or drain paint containers on the ground (paved or unpaved). • Clean brushes and containers only at sinks and stations that drain to the process sewer to the tailings system. • Paint out brushes to the extent possible before water washing (water-based paint) or solvent rinsing (oil-based paint). • Filter and reuse thinners and solvent whenever possible). Contain solids and unusable excess liquids for transfer to the tailings area Page 6 Best Management Practices Plan Revision 1.34: Juno 12. 2008October 2011 4.4 Management Practices for Ore Pad, Tailings Area, and Heavy Equipment Detailed instmctions for ore unloading, dust suppression, and tailings management are provided in the Mill SOPs. 4.4.1 Wash Down Vehicles and Equipment in Proper Areas • Wash down tmcks, trailers, and other heavy equipment only in areas designated for this purpose (such as wash_down pad areas and tile truck wash station). • At the truck wash station, make sure the water collection and recycling system is working before tuming on water sprays. 4.4.2 Manage Stockpiles to Prevent Windborne Contamination • Water spray the ore pad and unpaved areas at appropriate frequency in accordance with Mill SOPs. • Water spray stockpiles as required by opacity standards or weather conditions. • Don't over-water. Keep surfaces moist but minimize runoff water. 4.4.3 Keep Earthmoving Activities from Becoming Pollutant Sources • Schedule excavation, grading, and other earthmoving activities when extreme dryness and high winds will not be a factor (to prevent the need for excessive dust suppression). • Remove existing vegetation only when absolutely necessary. • Seed or plant temporary vegetation for erosion control on slopes. Page? A complete copy of Table 1 will be included in the Stormwater Best Management Practices Plan maintained at the Mill Site. TABLE 2 REAGENT YARD LIST REAGENT. QUANTITY7LBS) ^NUMBEROF'. ' " CAPACITY . ' QUANTITY7LBS) STORAGE TANKS .(GALLONS). . ' ADOGEN 2382 §T420 — ADVANTAGE 101M — AMERSITE Q — AMINE 238^ IQ.'I^O — AMMONIUM 54,000 —2 24,366 SULFATE(BULK) 24,366 AMMONIUM 4^30026,000 — SULFATE(BAGS) 4^30026,000 ANHYDROUS AMMONIA 107,920 2 31,409 CHEMFAC 100 12,800 — CLARIFLOC N 101P — TRIDECYLALCOHOL 45,430 — DIESEL FUEL 2 250 1 6,000 FLOCCULENT M1011N 30,550 — FLOCCULENT M1302C — GRINDING BALLS 48T29072.000 — ISODECANOL 16,430 — KEROSENE 1,344 31 10.16210.315 2 10.095 MACKANATE 3T4€0 10.095 MILLSPERSE 4r44^ — NALGO 2168 0 — NALCO 8816 0 — PERCOL 351 1,6000 — PERCOL ^06 13,060 — PERCOL 7^16 0 — POLOX 10,360 — POLYHALL YOF 0 — PROPANE 1 30T00025,589 SALT (BAGS) 39,280 — SALT (BULK) 0 —1 13.763 1 18.864 SODA ASH (BAGS) 39,280 — SODA ASH (BULK) 84,100 1 16,921 1 8,530 SODIUM CHLORATE 101,128 1 17.70016.921 1 10.60022.561 1 29.940 SODIUM HYDROXIDE 0 1 19,9054 SULFURIC ACID 4,801,440 1 1.600.0001.394.439 260,160 UNLEADED GASOLINE 1 3,000 USED OIL 1 5,000 Page 10 TABLE 3.0 LABORATORY CHEMICAL INVENTORY LIST ^ Chemical In Lab RQ! Quantitv in Stock Aluminum nitrate 2270 kg 1.8 kg Ammonium bifluoride 45.4 kg 2.27 kg Ammonium chloride 2270 kg 2.27 kg Ammonium oxalate 2270 kg 6.8 kg Ammonium thiocyanate 2270 kg 7.8 kg Antimony potassium tatrate 45.4 kg 0.454 n-8uty! acetate 2270 kg 4L Carbon tetraohlorido A.6A kg A-L Cyclohexane 454 kg 24 L Ferric chloride 454 kg 6.81 kg Ferrous ammonium sulfate 454 kg 0.57 Potassium chromate 4.54 kg 0.114 kg Sodium nitrite 45.4 kg 2.5 kg Sodium phosphate tribasic 2270kg 1.4 Zinc acetate 454 kq 0.91 kq Chemical. In Volatiles and Flammables Lockers (A.B.C) RQ! Quantitv in Stock Chloroform 4.54 kg 8 L Formaldehyde 45.4 kg <1 L of 37% solution Nitrobenzene 454 kg 12 L Toluene 454 kg 12L Chemical in Acid Shed RQ^ Quantity In Stock Chloroform 4.54 kg 55 qal Hydrochloric acid 2,270 kq 58 qal Nitrate acid 454 kg 5 L Phosphoric Acid 2,270 kg 10L Sulfuric acid 454 kg 25 L Hydrofluoric acid 45.4 kq 1 L Ammonium hydroxide 454 kq 18L 1. This list identifies chemicals which are regulated as hazardous substances under the Federal Water Pollution Control Act 40 CFR Part 117. The lab also stores small quantities of other materials that are not hazardous substances per the above regulation. 2. Reportable Quantities are those identified in 40 CFR Part 117 Table 117.3: "Reportable Quantities of Hazardous Substances Designated Pursuant to Section 311 of the Clean Water Act." Page 12 TABLE 4.0 REAGENT YARD/SMALL QUANTITY CHEMICALS LIST ^ CHEMICAL , . RQ! QUANTITY IN . STORAGE r - COMPOUND . Acetic Acid, Glacial 1,000 Ibs 4 qal Ammonium Hydroxide 1,000 Ibs 5L Carbon Disulfide 100 Ibo 04bs Calcium Hypochlorite 10 Ibs 2 kq (4.4 Ibs) Chlorine 10 Ibs 0 Ibs Ferrous Sulfate Heptahydrate 1,000 Ibs 5 kq (11 Ibs) Hydrochloric 5,000 Ibs 60 qal of 40% solution Nitric Acid 1,000 Ibs 10 L Potassium Permanganate 0.1 N 32 gal 5 kq (11 Ibs) Sodium Hypochlorite 5.5% 100 Ibs 2 kg (11 Ibs) of 5.5% solution Silver Nitrate 1 Ib Olbs Trichloroethylene 100 1b 2 L Xylene (Mixod Isomers) 100 Ibs Q [[jg This list identifies chemicals which are regulated as hazardous substances under the Federal Water Pollution Control Act 40 CFR Part 117, Materials in this list are stored in a locked storage compound near the bulk storage tank area. The Mill also stores small quantities of other materials that are not hazardous substances per the above regulation. Reportable Quantities are those identified in40 CFR Part 117 Table 117.3: "Reportable Quantities of Hazardous Substances Designated Pursuant to Section 311 of the Clean Water Act." Page 13 TABLE 5.0 REAGENT YARD/BULK CHEMICALS LIST' REAGENT RQ' QUANTITY IN REAGENT YARD Sulfuric Acid 1,000 lbs 9,000,000 Ibs Floe tf301 NoriG 1,200 Ibs Hyperfloc 102 None 1,500 Ibs Ammonia - East Tank 100 Ibs Olbs Ammonia - West Tank 100 lbs 105,000 lbs Kerosene 100 gal 500 gal Salt (Bags) None 2.000 Ibs20.000 Ibs Ammonium Hydrogendifluorido NODG 20,150 Ibs Soda Ash Dense (Bag) None 04bs50.000 Ibs Phosphoric Acid 5,000 Ibs 6,300 Ibs Polyox None 490 Ibs Millsperso None 1,110 Ibs Naico TX760 NoriQ 9 barrels Naico 7200 Noric 1,690 Ibs Tributyl phosphate None 9,450 Ibs Distillatos NoriG 100 gal Diesel 100 gal Approx. 3300 gal Gasoline 100 gal Approx. 6000 gal Alamine 336 drums None 0-lbs8.250 qal Floe 100 None Q lljg Floe 208 Nono 0-tes Floe 004 None 04bs Hyporfloc 621 Nono Q lljg Salt(Bulk Solids) None 04bs50.000 Ibs Salt(Bulk Solutions) None O4bs9.000 aai Caustic Soda 1,000 Ibs 04bs16.000 lbs Ammonium Sulfate None 04bs150.000lbs Sodium Chlorate None 20.000 Ibs350.000 lbs Alamino 335 Bulk Nono Q lljg Alamine 310 Bulk None 0 lbs Isodecanol None O4bs2.420 aai Vanadium Pentoxide3 1000 Ibs 30,000 Ibs Yellowcake3 None <100,000 Ibs Ammonia Meta Vanadate 1000 Ibs 0 Ibs Floe 655 21.000 Ibs Floe 712 1.250 Ibs 1. This list identifies all chemicals in the reagent yard whether or not they are regulated as hazardous substances under the Federal Water Pollution Control Act 40 CFR Part 117. 2. Reportable Quantities are those identified in 40 CFR Part 117 Table 117.3: "Reportable Quantities of Hazardous Substances Designated Pursuant to Section 311 of the Clean Water Act." 3. Vanadium Pentoxide and Yellowcake, the Mill's products, are not stored in the Reagent Yard itself, but are present in closed containers in the Mill Building anc^brMill Yard Page 14 TABLE 6.0 PETROLEUM PRODUCTS AND SOLVENTS LIST' PRODUCT RQ QUANTITY IN WAREHOUSE Lubricating Oils in 55 gallon drums 100 gal 1,540 gallons Transmission Oils 100 gal 0-110 oallons Water Soluble Oils 100 gal 3&-110 oallons Xylene (mixed isomers) 100 gal 0 gallons Toluene 1000 gal 0 gallons Varsol Solvent 100 gal 0 gallons (2% trimethyl benzene in petroleum 0 gallons distillates) This list includes all solvents and petroleum-based products in the M warehouse petroleum and chemical storage aisles. Reportable Quantities are those identified in 40 CFR Part 117 Table 117.3: "Reportable Quantities of Hazardous Substances Designated Pursuant to Section 311 of the Clean Water Act." Page 15 O it & C E la n a g e i •e s i d e r Mi l l IV Q. V Op e r a t i o n s Fo r e m a n Sh i f t F o r e m a n (4 ) op e r a t i n g Cr e w s Op e r a t i o n s Fo r e m a n Sh i f t F o r e m a n (4 ) op e r a t i n g Cr e w s Figure 4 White Mesa Mill Denison Mines (USA) Corporation Organizational Structure Page 21 e P 2 « .lis f u 2 S < — £c« « Up o •- • aa (S V fft t: e 1: 'S J; 0) ^ Q ro 0) ° % CL Q. 01 APPENDICES page 23 Appendix 1 White Mesa Mill Spill Prevention. Control, and Countermeasures Plan Page 24 The Spill Prevention, Control and Countermeasures Plan ("SPCC") is currently under review. The W.^ Mesa M. E.e.encv Response P,an Is no. .e,n. .esu..„e. .cause .e.e a. no chan.es STORMWATER BEST MANGEMENT PRACTICES PLAN for White Mesa Uranium Mill 6425 South Highway 191 P.O. Box 809 Blanding, Utah October 2011 Prepared by: Denison Mines (USA) Corp. 1050 17th Street, Suite 950 Denver, CO 80265 TABLE OF CONTENTS 1.0 INTRODUCTION/PURPOSE 1 2.0 SCOPE 2 3.0 RESPONSIBILITY 3 4.0 BEST MANAGEMENT PRACTICES 4 4.1 General Management Practices Applicable to All Areas 4 4.1.1 Keep Potential Pollutants from Contact with Soil, and Surface Water: 4 4.1.2 Keep Potential Pollutants from Contact with Precipitation 4 4.1.3 Keep Paved Areas from Becoming Pollutant Sources 4 4.1.4 Inspection and Maintenance of Diversion Ditches and Drainage Channels within the Process and Reagent Storage Area 4 4.1.5 Recycle Fluids Whenever Possible: 4 4.2 Management Practices for Process and Laboratory Areas 5 4.2.1 Clean Up Spills Properly 5 4.2.2 Protect Materials Stored Outdoors 5 4.2.3 Management 5 4.2.4 Materials Management 5 4.3 Management Practices for Maintenance Activities 6 4.3.1 Keep a Clean Dry Shop 6 4.3.2 Manage Vehicle Fluids 6 4.3.3 Use Controls During Paint Removal 6 4.3.4 Use Controls During Paint Application and Cleanup 6 4.4 Management Practices for Ore Pad, Tailings Area, and Heavy Equipment 7 4.4.1 Wash Down Vehicles and Equipment in Proper Areas 7 4.4.2 Manage Stockpiles to Prevent Windborne Contamination 7 4.4.3 Keep Earthmoving Activities from Becoming Pollutant Sources 7 Figures Figure 1: White Mesa Mill Site Layout 16 Figure2: White Mesa Mill Site Drainage Basins 17 Figure 3: Denison Mines (USA) Corp.- White Mesa Mill Management Organization Chart 19 Figure 4: Denison Mines (USA) Corp. - Corporate Management Organizational Chart 20 Tables TABLE 1.0: White Mesa Mill Management Personnel Responsible for Implementing This BMPP 9 TABLE 2.0: REAGENT YARD LIST 10 TABLE 3.0: LABORATORY CHEMICAL INVENTORY LIST 1 11 TABLE 4.0: REAGENT YARD/SMALL QUANTITY CHEMICALS LIST 1 12 TABLE 5.0: EAGENT YARD/BULK CHEMICALS LIST 1 13 TABLE 6.0: PETROLEUM PRODUCTS AND SOLVENTS LIST 1 14 Appendices Appendix 1 White Mesa Mill Spill Prevention, Control, and Countermeasures Plan Appendix 2 White Mesa Mill Emergency Response Plan Best Management Practices Plan Revision 1.4: October 2011 1.0 INTRODUCTION/PURPOSE Denison Mines (USA) Corp. ("DUSA") operates the White Mesa Uranium Mill ("the Mill) in Blanding, Utah. The Mill is a net water consumer, and is a zero-discharge facility with respect to water effluents. That is, no water leaves the Mill site because the Mill has: • no outfalls to public stormwater systems, • no surface runoff to public stormwater systems, • no discharges to publicly owned treatment works ("POTWs"), and • no discharges to surface water bodies. The State of Utah issued Groundwater Discharge Permit No. UGW370004 to DUSA on March 8, 2005. As a part of compliance with the Permit, DUSA is required to submit a Stormwater Best Management Practices Plan ("BMPP") to the Executive Secretary of the Division of Radiation Control, Utah Department of Environmental Quality. This BMPP presents operational and management practices to minimize or prevent spills of chemicals or hazardous materials, which could result in contaminated surface water effluents potentially impacting surface waters or ground waters through runoff or discharge connections to stormwater or surface water drainage routes. Although the Mill, by design, cannot directly impact stormwater, surface water, or groundwater, the Mill implements these practices in a good faith effort to minimize all sources of pollution at the site. Page 1 Best Management Practices Plan Revision 1.4: October 2011 2.0 SCOPE This BMPP identifies practices to prevent spills of chemicals and hazardous materials used in process operations, laboratory operations, and maintenance activities, and minimize spread of particulates from stockpiles and tailings management areas at the Mill. Storage of ores and altemate feeds on the ore pad, and containment of tailings in the Mill tailings impoundment system are not considered "spills" for the purposes of this BMPP. The Mill site was constructed with an overall grade and diversion ditch system designed to channel all surface runoff, including precipitation equivalent to a Probable Maximum Precipitation/Probable Maximum Flood ("PMP/PMF") storm event, to the tailings management system. In addition. Mill tailings, all other process effluents, all solid waste and debris (except used oil and recyclable materials), and spilled materials that cannot be recovered for reuse are transferred to one or more of the tailings cells in accordance with the Mill's NRC license conditions. All of the process and laboratory building sinks, sumps, and floor drains are tied to the transfer lines to the tailings impoundments. A site map of the Mill is provided in Figure 1. A sketch of the site drainage basins is provided in Figure 2. As a result, unlike other industrial facilities, whose spill management programs focus on minimizing the introduction of chemical and solid waste and wastewater into the process sewers and storm drains, the Mill is permitted by NRC license to manage some spills via draining or wash down to the process sewers, and ultimately the tailings system. However, as good environmental management practice, the Mill attempts to minimize: 1. the number and size of material spills, and 2. the amount of unrecovered spilled material and wash water that enters the process sewers after a spill cleanup. Section 4.0 itemizes the practices in place at the Mill to meet these objectives. Requirements and methods for management, recordkeeping, and documentation of hazardous material spills are addressed in the DUSA White Mesa Mill Spill Prevention, Control and Countermeasures ("SPCC") Plan, the Emergency Response Plan ("ERP"),, and the housekeeping procedures incorporated in the White Mesa Mill Standard Operating Procedures ("SOPs"). The latest revisions of the SPCC plan and the ERP are provided in their entirety in Appendices 1 and 2, respectively. Page 2 Best Management Practices Plan Revision 1.4: October 2011 3.0 RESPONSIBILITY All Mill personnel are responsible for implementation of the practices in this BMPP. DUSA White Mesa Mill management is responsible for providing the facilities or equipment necessary to implement the practices in this BMPP. The Mill Management Organization is presented in Figure 3. The DUSA Corporate Management Organization is presented in Figure 4. An updated spill prevention and control notification list is provided in Table 1. Page 3 Best Management Practices Plan Revision 1.4: October 2011 4.0 BEST MANAGEMENT PRACTICES A summary list and inventory of all liquid and solid materials managed at the Mill is provided in Tables 2 through 5. 4.1 General Management Practices Applicable to All Areas 4.1.1 Keep Potential Pollutants from Contact with Soil, and Surface Water: • Store hazardous materials and other potential pollutants in appropriate containers. • Label the containers. • Keep the containers covered when not in use. 4.1.2 Keep Potential Pollutants from Contact with Precipitation • Store bulk materials in covered tanks or drums. • Store jars, bottle, or similar small containers in buildings or under covered areas. • Replace or repair broken dumpsters and bins. • Keep dumpster lids and large container covers closed when not in use (to keep precipitation out). 4.1.3 Keep Paved Areas from Becoming Pollutant Sources • Sweep paved areas regularly, and dispose of debris in the solid waste dumpsters or tailings area as appropriate. 4.1.4 Inspection and Maintenance of Diversion Ditches and Drainage Channels within the Process and Reagent Storage Area • Diversion ditches, drainage channels and surface water control structures in and around the Mill area will be inspected at least monthly in accordance with the regularly scheduled inspections required by Groundwater Discharge Permit No. UGW370004, and by product Materials License #UT1900479. Areas requiring maintenance or repair, such as excessive vegetative growth, channel erosion or pooling of surface water runoff, will be reported to site management and maintenance departments for necessary action to repair damage or perform reconstruction in order for the control feature to perform as intended. Status of maintenance or repairs will be documented during follow up inspections and additional action taken if necessary. 4.1.5 Recycle Fluids Whenever Possible: • When possible, select automotive fluids, solvents, and cleaners that can be recycled or reclaimed • When possible, select consumable materials from suppliers who will reclaim empty containers. • Keep spent fluids in properly labeled, covered containers until they are picked up for recycle or transferred to the tailings area for disposal. Page 4 Best Management Practices Plan Revision 1.4: October 2011 4.2 Management Practices for Process and Laboratory Areas 4.2.1 Clean Up Spills Properly • Clean up spills with dry cleanup methods (absorbents, sweeping, collection drums) instead of water whenever possible. • Clean spills of stored reagents or other chemicals immediately after discovery. • (Groundwater Discharge Permit No. UGW370004, Section I.D. lO.c.) • Recover and re-use spilled material whenever possible. • Keep supplies of rags, sorbent materials (such as cat litter), spill collection drums, and personnel protective equipment ("PPE") near the areas where they may be needed for spill response. • If spills must be washed down, use the minimum amount of water needed for effective cleanup. 4.2.2 Protect Materials Stored Outdoors • If drummed feeds or products must be stored outdoors, store them in covered or diked areas when possible. • If drummed chemicals must be stored outdoors, store them in covered or diked areas when possible. • Make sure drums and containers stored outdoors are in good condition and secured against wind or leakage. Place any damaged containers into an overpack drum or second container. 4.2.3 Management • When possible, recycle and reuse water from flushing and pressure testing equipment. When possible, wipe down the outsides of containers instead of rinsing them off in the sink. • When possible, wipe down counters and work surfaces instead of hosing or rinsing them off to sinks and drain 4.2.4 Materials Management • Purchase and inventory the smallest amount of laboratory reagent necessary. • Do not stock more of a reagent than will be used up before its expiration date. • All new construction of reagent storage facilities will include secondary containment which shall control and prevent any contact of spilled reagents, or otherwise released • reagent or product, with the ground surface. (Groundwater Discharge Permit No. • UGW370004, Section I.D.3.g.) Page 5 Best Management Practices Plan Revision 1.4: October 2011 4.3 Management Practices for Maintenance Activities 4.3.1 Keep a Clean Dry Shop • Sweep or vacuum shop floors regularly. • Designate specific areas indoors for parts cleaning, and use cleaners and solvents only in those areas. • Clean up spills promptly. Don't let minor spills spread. • Keep supplies of rags, collection containers, and sorbent material near each work area where they are needed. • Store bulk fluids, waste fluids, and batteries in an area with secondary containment (double drum, drip pan) to capture leakage and contain spills. 4.3.2 Manage Vehicle Fluids • Drain fluids from leaking or wrecked/damaged vehicles and equipment as soon as possible. Use drip pans or plastic tarps to prevent spillage and spread of fluids. • Promptly contain and transfer drained fluids to appropriate storage area for reuse, recycle, or disposal. • Recycle automotive fluids, if possible, when their useful life is finished. 4.3.3 Use Controls During Paint Removal • Use drop cloths and sheeting to prevent windbome contamination from paint chips and sandblasting dust. • Collect, contain, and transfer, as soon as possible, accumulated dusts and paint chips to a disposal location in the tailings area authorized to accept waste materials from maintenance or constmction activities. 4.3.4 Use Controls During Paint Application and Cleanup • Mix and use the right amount of paint for the job. Use up one container before opening a second one. • Recycle or reuse leftover paint whenever possible. • Never clean bmshes or rinse or drain paint containers on the ground (paved or unpaved). • Clean bmshes and containers only at sinks and stations that drain to the process sewer to the tailings system. • Paint out bmshes to the extent possible before water washing (water-based paint) or solvent rinsing (oil-based paint). • Filter and reuse thinners and solvent whenever possible). Contain solids and unusable excess liquids for transfer to the tailings area Page 6 Best Management Practices Plan Revision 1.4: October 2011 4.4 Management Practices for Ore Pad, Tailings Area, and Heavy Equipment Detailed instmctions for ore unloading, dust suppression, and tailings management are provided in the Mill SOPs. 4.4.1 Wash Down Vehicles and Equipment in Proper Areas • Wash down tmcks, trailers, and other heavy equipment only in areas designated for this purpose (such as wash down pad areas and tile tmck wash station). • At the tmck wash station, make sure the water collection and recycling system is working before tuming on water sprays. 4.4.2 Manage Stockpiles to Prevent Windborne Contamination • Water spray the ore pad and unpaved areas at appropriate frequency in accordance with Mill SOPs. • Water spray stockpiles as required by opacity standards or weather conditions. • Don't over-water. Keep surfaces moist but minimize mnoff water. 4.4.3 Keep Earthmoving Activities from Becoming Pollutant Sources • Schedule excavation, grading, and other earthmoving activities when extreme dryness and high winds will not be a factor (to prevent the need for excessive dust suppression). • Remove existing vegetation only when absolutely necessary. • Seed or plant temporary vegetation for erosion control on slopes. Page 7 A complete copy of Table 1 will be included in the Stormwater Best Management Practices Plan maintained at the Mill Site. TABLE 2 REAGENT YARD LIST REAGENT " ^ QUANTITY . ; NUMBER.OF-. .5. : cAPAc\T:^yy ^ (LBS)'v • JSTQRAGE^MI^ AMMONIUM 54,000 2 24,366 SULFATE(BULK) AMMONIUM 26,000 — SULFATE(BAGS) ANHYDROUS AMMONIA 107,920 2 31,409 TRIDECYLALCOHOL 45,430 DIESEL FUEL 2 250 1 6,000 GRINDING BALLS 72,000 — KEROSENE 1,344 1 10,315 2 10,095 POLOX 10,360 PROPANE 1 25,589 SALT (BAGS) 39,280 — SALT (BULK) 0 1 13,763 1 18,864 SODA ASH (BAGS) 39,280 — SODA ASH (BULK) 84,100 1 16,921 1 8,530 SODIUM CHLORATE 101,128 1 16,921 1 22,561 1 29,940 SODIUM HYDROXIDE 0 1 19,905 SULFURIC ACID 4,801,440 1,394,439 UNLEADED GASOLINE 1 3,000 USED OIL 1 5,000 Page 10 TABLE 3.0 LABORATORY CHEMICAL INVENTORY LIST ^ Chemical In Lab RQ" Quantitv in Stock Aluminum nitrate 2270 kg 1.8 kg Ammonium bifluoride 45.4 kg 2.27 kg Ammonium chloride 2270 kg 2.27 kg Ammonium oxalate 2270 kg 6.8 kg Ammonium thiocyanate 2270 kg 7.8 kg Antimony potassium tatrate 45.4 kg 0.454 n-8utyl acetate 2270 kg 4L Cyclohexane 454 kg 24 L Ferric chloride 454 kg 6.81 kg Ferrous ammonium sulfate 454 kg 0.57 Potassium chromate 4.54 kg 0.114 kg Sodium nitrite 45.4 kg 2.5 kg Sodium phosphate tribasic 2270kg 1.4 Zinc acetate 454 kg 0.91 kg Chemical, in Volatiles and Flammables Lockers (A.B.C) RQ! Quantitv in Stock Chloroform 4.54 kg 8L Formaldehyde 45.4 kg <1L of 37% solution Nitrobenzene 454 kg 12L Toluene 454 kg 12L Chemical in Acid Shed RQ^' Quantity in Stock Chloroform 4.54 kg 55 gal Hydrochloric acid 2,270 kg 58 gal Nitrate acid 454 kg 5L Phosphoric Acid 2,270 kg IOL Sulfuric acid 454 kg 25 L Hydrofluoric acid 45.4 kg 1 L Ammonium hydroxide 454 kg 18L 1. This list identifies chemicals which are regulated as hazardous substances under the Federal Water Pollution Control Act 40 CFR Part 117. The lab also stores small quantities of other materials that are not hazardous substances per the above regulation. 2. Reportable Quantities are those identified in 40 CFR Part 117 Table 117.3: "Reportable Quantities of Hazardous Substances Designated Pursuant to Section 311 of the Clean Water Act." Page 11 TABLE 4.0 REAGENT YARD/SMALL QUANTITY CHEMICALS LIST ^ ^WimiemMMyyym-yyym my'^:':myMmmj.m^i.^ ymysii6¥(P^€0y^ feil^SfeQMPO^ Acetic Acid, Glacial 1,000 Ibs 4gal Ammonium Hydroxide 1,000 Ibs 5L Calcium Hypochlorite 10 Ibs 2 kg (4.4 Ibs) Chlorine 10 Ibs Olbs Ferrous Sulfate Heptahydrate 1,000 Ibs 5kg(11lbs) Hydrochloric 5,000 Ibs 60 gal of 40% solution Nitric Acid 1,000 Ibs IOL Potassium Permanganate 0.1 N 32 gal 5 kg (1 libs) Sodium Hypochlorite 5.5% 100 Ibs 2 kg (11 Ibs) of 5.5% solution Silver Nitrate 1 Ib 0 Ibs Trichloroethylene 100 Ib 2 L This list identifies chemicals which are regulated as hazardous substances under the Federal Water Pollution Control Act 40 CFR Part 117, Materials in this list are stored in a locked storage compound near the bulk storage tank area. The Mill also stores small quantities of other materials that are not hazardous substances per the above regulation. Reportable Quantities are those identified in40 CFR Part 117 Table 117.3: "Reportable Quantities of Hazardous Substances Designated Pursuant to Section 311 of the Clean Water Act." Page 12 TABLE 5.0 REAGENT YARD/BULK CHEMICALS LIST^ REAGENT RQ' QUANTITY IN REAGENT YARD Sulfuric Acid 1.000 Ibs 9,000,000 Ibs Hyperfloc 102 None 1,500 Ibs Ammonia - East Tank 100 Ibs Olbs Ammonia - West Tank 100 Ibs 105,000 Ibs Kerosene 100 gal 500 gal Salt (Bags) None 20,000 Ibs Soda Ash Dense (Bag) None 50,000 Ibs Polyox None 490 Ibs Tributyl phosphate None 9,450 Ibs Diesel 100 gal Approx. 3300 gal Gasoline 100 gal Approx. 6000 gal Alamine 336 drums None 8,250 gal Salt(Bulk Solids) None 50,000 Ibs Salt(Bulk Solutions) None 9,000 gal Caustic Soda 1,000 Ibs 16,000 Ibs Ammonium Sulfate None 150,000 Ibs Sodium Chlorate None 350,000 Ibs Alamine 310 Bulk None Olbs Isodecanol None 2,420 gal Vanadium Pentoxide3 1000 Ibs 30,000 Ibs Yellowcake3 None <100,000 Ibs Ammonia Meta Vanadate 1000 Ibs Olbs Floe 655 21,000 Ibs Floe 712 1,250 Ibs 1. This list identifies all chemicals in the reagent yard whether or not they are regulated as hazardous substances under the Federal Water Pollution Control Act 40 CFR Part 117. 2. Reportable Quantities are those identified in 40 CFR Part 117 Table 117.3: "Reportable Quantities of Hazardous Substances Designated Pursuant to Section 311 of the Clean Water Act." 3. Vanadium Pentoxide and Yellowcake, the Mill's products, are not stored in the Reagent Yard itself, but are present in closed containers in the Mill Building and/or Mill Yard Page 13 TABLE 6.0 PETROLEUM PRODUCTS AND SOLVENTS LIST^ PRODUCT RQ QUANTITY IN RQ WAREHOUSE Lubricating Oils in 55 gallon drums 100 gal 1,540 gallons Transmission Oils 100 gal 110 gallons Water Soluble Oils 100 gal 110 gallons Xylene (mixed isomers) 100 gal 0 gallons Toluene 1000 gal 0 gallons Varsol Solvent 100 gal 0 gallons (2% trimethyl benzene in petroleum distillates) This list includes all solvents and petroleum-based products in the Mill warehouse petroleum and chemical storage aisles. Reportable Quantities are those identified in 40 CFR Part 117 Table 117.3: "Reportable Quantities of Hazardous Substances Designated Pursuant to Section 311 of the Clean Water Act." Page 14 e a u o & o U WD w NN ^ B o s Cl 1 2 SJD — ca S e S ® - '-s 2 O CTl 00 Figure 4 White Mesa Mill Denison Mines (USA) Corporation Organizational Structure Page 20 (U CUO fO Q. S *-C 0 b is w ^ c/5 « — .Sf .2 e .2 (9 ^ 1 o *s U 4-- O ° (Ll (U •5 ° LJ. (U 0} it ^ o u 4-> C ns o) o e Q. Q. s -5 Q. <U > Q Appendix 2 White Mesa Mill Emergency Response Plan Page 24 The White Mesa Mill Emergency Response Plan is not being resubmitted because there are no changes at this time. StateofUtah JONM. HUNTSMAN,JR. Govemor GARY HERBERT Lieutenant Govemor Department of Enviromnental Quality Amanda Smith Acting Executive Director DIVISION OF RADIATION CONTROL Dane L. Finerfixjck Director September 30,2011 CERTIFIED MAIL (Retum Receipt Requested) Jo Ann Tischler Director, Compliance and Permitting Denison Mines (USA) Corp. (DUSA) 1050 Seventeenth Street, Suite 950 Denver, CO 80265 Dear Ms. Tischler: SUBJECT: Proposed Concrete Pads for Drum Management, White Mesa Uranium Mill Ground Water Discharge Permit No. UGW370004; Conditional Approval On September 26,2011 the Division ofRadiation Control (DRC) received through email a smgle-sheet plan for new concrete pads for drum management at the Altemate Feed Area at the DUSA White Mesa Uranium Mill, near Blanding, Utah. The subject line in the cover message accompanying the plan referenced the September 1, 2011 Request for Information and Confirmatory Action Letter, Storm water Inspection. DRC understands the project to include placement of concrete flatwork as a management surface for drums of feedstock. The pads will include low-profile rolled curb at the periphery to provide material contairmient for spills that may occur. The pads will slope to existing drain simips, thus preventing spilled feedstock material from washing onto surrounding soils. DRC has reviewed the submitted plan for conformance with the intent of Part I.D.I 1 of the White Mesa Uranium Mill Ground Water Discharge Permit No. UGW370004 (Permit) and find the plan to comply with this Permit requirement; therefore, the plan is approved, subject to the following conditions: 1. DUSA shall submit As-Built drawings within 14 calendar days upon completion ofthe project for Executive Secretary review and approval. The As-Built drawings will include a section or detail of the curbing constructed on the periphery of the pads as a material containment feature. The plan will include sufBcient spot elevations to detail how the pads will drain. The record drawing will reflect any deviations fi'om the approved plan. 2. The pads shall not be placed in service until approval of the As-Built drawings by the Executive Secretary. 168 North 1950 West • Salt Lake City, UT MaiUng Address: P.O. Box 144850 • Salt Lake City, UT 84114-4850 Telephone (801) 536-4250 • Fax (801) 533-4097 • T.D.D. (801) 536^14 www.deq.utah.gov Printed on 100% recycled paper Jo Arm Tischler September 28,2011 Page 2 DRC limited its review of the subject plan to evaluating conformance with the intent of the Permit. No structural evaluation or value engineering was performed as part of the review. Ifyou have any questions on the above, please contact Russ Topham, of my staff, at (801) 536-4256. UTAH WATER QUALITY BOARD Rusty Lundberg ^ Co-Executive Secretary RL:RT:rt F:\rtopham\DUSA\DUSA Altemate Feed Dmm Management.doc '(We m m - Wi'-'y' ^^^^^ " '.4fym^ •:'ym. y^ •••• 'M-^'-s^^^ Attachment E Attachment F ['i-ymt •A wyf---'