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HomeMy WebLinkAboutDAQ-2024-004556 1 DAQC-CI105720001-23a Site ID 10572 (B1) MEMORANDUM TO: FILE – KENNECOTT UTAH COPPER (KUC) – Power Plant, Tailings, Central Lab THROUGH: Chad Gilgen, Minor Source Compliance Manager FROM: Connor Kijowski, Environmental Scientist DATE: October 13, 2023 SUBJECT: FULL COMPLIANCE EVALUATION, Minor, Salt Lake County INSPECTION DATE: August 8, 2023 SOURCE LOCATION: Tailings: 11984 West Highway 202, Salt Lake County, Utah MAILING ADDRESS: 4700 Daybreak Parkway, South Jordan, Utah 84009 SOURCE CONTACTS: Sean Daly – Senior Environmental Advisor - 801-913-4456 OPERATING STATUS: Power Plant is in the process of being demolished. Tailings operations are 24/7. Central Lab was online. PROCESS DESCRIPTION: The Kennecott Power Plant was a four-unit, 175 MW capacity steam turbine generator facility. This plant is off line and has been locked out as it will no longer be used. It is currently in the process of being demolished and was inaccessible for inspection. Tailings Impoundment: Mine tailings are transported in slurry form via pipeline to a man-made tailings pond. The south impoundment (5700 acres) has been closed for several years to additional material and is entirely reclaimed. The north impoundment (3300 acres) was added to the tailings impoundment system to facilitate the storage of additional tailings. Fugitive dust emissions are controlled at this facility by water trucks, water cannon, other surface treatments, reclaimed vegetation, and by cycling the peripheral discharge flow to keep the interior impoundments wet. As the North pond is filled to capacity, dikes are raised to accommodate additional material. Underflow is used to build the impoundment (higher solids content) and overflow to fill it. The slurry is discharged into the pond via a peripheral discharge system to 16 cells. Active sections of the discharge system are rotated in such a way as to maintain surface moisture in all sections of the pond, thus minimizing potential fugitive dust. Adjacent areas that are disturbed during dike raising activities are chemically treated and/or re-vegetated to minimize dust. ) 1 2 Analytical Laboratory: KUC operates an analytical laboratory where samples are processed to determine mineral content at various phases between ore and finished metal products. A variety of inorganic analytical methods are used to extract and analyze for analytes. Baghouses are used to control various rock and mineral grinding operations, and fume hoods are used in the analytical areas. Most fume hoods are vented to the atmosphere unfiltered; some are vented through the scrubber. APPLICABLE REGULATIONS: Approval Order – AN105720040-20, dated February 2, 2020 (Power Plant) Approval Order – AN05720108-06, dated April 6, 2006 (Tailings) – incorporates SIP conditions. 40 CFR Part 63 Subpart CCCCCC: National Emission Standards for Hazardous Air Pollutants for Source Category: Gasoline Dispensing Facilities 40 CFR Part 63, Subpart ZZZZ: National Emissions Standards for Hazardous Air Pollutants for Stationary Reciprocating Internal Combustion Engines SOURCE INSPECTION EVALUATION: AO 0572018-06 Tailings General Conditions: 1. This Approval Order (AO) applies to the following company: Site Office Corporate Office Location Kennecott, Utah Copper Corporation Kennecott, Utah Copper Corporation 11984 West Highway 202 P.O. Box 6001 Magna, Utah 84044-6001 Magna, Utah 84044-6001 Phone Number: (801) 569-7277 (801) 569-6000 Fax Number: (801) 569-7227 (801) 569-7192 The equipment listed in this AO shall be operated at the following location: South of I-80 and West of 8,000 West, Salt Lake City, Universal Transverse Mercator (UTM) Coordinate System: UTM Datum NAD27 4,513 kilometers Northing, 405 kilometers Easting, Zone 12 Status: Not an inspection item. 2. All definitions, terms, abbreviations, and references used in this AO conform to those used in the Utah Administrative Code (UAC) Rule 307 (R307) and Title 40 of the Code of Federal Regulations (40 CFR). Unless noted otherwise, references cited in these AO conditions refer to those rules. Status: Not an inspection item. 3 3. The limits set forth in this AO shall not be exceeded without prior approval in accordance with R307-401. Status: In Compliance. No limits set forth in this AO appear to have been exceeded. 4. Modifications to the equipment or processes approved by this AO that could affect the emissions covered by this AO must be reviewed and approved in accordance with R307-401-1. Status: In Compliance. No modifications to the equipment or processes were observed during the inspection. 5. All records referenced in this AO which are required to be kept by the owner/operator, shall be made available to the Executive Secretary or Executive Secretary’s representative upon request. Records shall be kept for the following minimum periods: A. Emission inventories Five years from the due date of each emission statement or until the next inventory is due, whichever is longer. B. All other records Five years Status: In Compliance. Records are kept according to the above criteria. Records were made available upon request and reviewed on site, as well as afterwards via email. 6. Kennecott Utah Copper Corporation (KUCC) shall install and operate the liquid petroleum (LP) fired emergency generator and shall operate the Tailings Impoundment Complex in accordance with the terms and conditions of this AO, which was written pursuant to Kennecott’s Notice of Intent (NOI) submitted to the Division of Air Quality (DAQ) on January 11, 2006, and additional information submitted on February 7, 2006, February 16, 2006, and February 21, 2006. Status: In Compliance. The equipment is installed and operational. See specific conditions below. 7. The KUCC Tailings Impoundment is a State Implementation Plan (SIP) source and is listed in Section IX, Part H, Subpart 2.i(2). Status: Statement of fact. Not an inspection item. 8. This AO shall replace the AO (DAQE-AN0572017-05), dated July 18, 2005 Status: Statement of fact. Not an inspection item. 9. The approved installations shall consist of the following equipment or equivalent*: One Liquefied Petroleum (LP) Fired Emergency Generator Maximum rating: 75 Brake Horsepower * Equivalency shall be determined by the Executive Secretary. Status: In Compliance. The generator is correct as listed. No other equipment was observed. 4 10. The minimum cycle time required for wetting all interior beach areas of the North impoundment between February 15 and November 15 shall be at least every four days. Status: In Compliance. An automated system is programmed to cycle within the required timeframe. Watering records are kept in a logbook to verify proper cycling is taking place. Records were provided and reviewed during the inspection. 11. If between February 15 and November 15 of each calendar year Kennecott's weather forecast is for a wind speed at more than 25 mph for more than one hour, the procedures listed below shall be followed within 48 hours of issuance of the forecast: A. Alert the DAQ promptly. B. Continue surveillance and coordination. Status: In Compliance. The company has a weather forecaster and pre-wind event notices are made (an email is also sent to DAQ inspector) and daily inspections as well as additional dust control measures as needed. 12. KUCC shall notify the Executive Secretary in writing when the installation of the generator listed in Condition #9 has been completed and is operational, as an initial compliance inspection is required. To insure proper credit when notifying the Executive Secretary, send your correspondence to the Executive Secretary, Attn: Compliance Section. If installation has not been completed within eighteen months from the date of this AO, the Executive Secretary shall be notified in writing on the status of the installation. At that time, the Executive Secretary shall require documentation of the continuous installation of the operation and may revoke the AO in accordance with R307-401-11. Status: In Compliance. The generator has been installed and is operational. The initial compliance inspection has been done on this unit, and multiple inspections have been performed since. For these reasons, the source is considered in compliance with this condition. Limitations and Tests Procedures 13. Visible emissions caused by fugitive dust shall not exceed 10% at the property boundary, and 20% onsite except during periods when wind speeds exceed the value specified in UAC R307-309 and control measures in the most recently approved dust control plan are being taken. The fugitive dust control plan shall utilize the fugitive dust control strategies listed in UAC R307-309. Opacity observations of emissions from stationary sources shall be conducted according to R307-309-5(3). Status: In Compliance. No visible emissions were observed. The company is using the Fugitive Dust Abatement Program (FDAP) which was submitted as part of the AO process and is based on controls from R307-309. Only minimal opacity was observed during the inspection. The FDAP is attached to the AO as Appendix A. 5 Fuels 14. KUCC shall only use LP in the communications emergency generator. Monitoring: Records required for the LP fired emergency generator will serve as monitoring. Recordkeeping: KUCC shall keep one of the following sets of records, as applicable: 1) Documentation that the emission unit can only burn LP gas; 2) Documentation that the fuels other than LP gas cannot be supplied to the emission unit without modification of the fuel supply system. Status: In Compliance. Only LP is used in the communications emergency generator. No other connections or fuel types are available. Roads and Fugitives 15. To minimize fugitive dust emissions at the Tailings Impoundment Complex, magnesium chloride or other stabilization methods approved by the Executive Secretary, shall be applied as necessary on all routinely used, unpaved roadways as discussed in the most recent Tailings Impoundment Fugitive Dust Abatement Program. A copy of the most recent Fugitive Dust Abatement Program is attached to this document as Appendix A. All Fugitive Dust Abatement Programs shall be submitted to the Executive Secretary, attention Major New Source Review Section, for approval. Supplemental stabilization to include other dust causing activities shall be by water sprays or other methods on an as- needed basis or as determined necessary and approved by the Executive Secretary. The owner/operator shall comply with UAC R307-309. Status: In Compliance. Unpaved roads and other unpaved operational areas used by mobile equipment are water sprayed or have applications of magnesium chloride (MgCl2) to control fugitive dust. The source uses a contractor for the tailings area. Unpaved road inspections are conducted and recorded daily by contractor and sprayed as needed. The source submits a quarterly report detailing what has been applied and how many acres were treated. The most recent quarterly report was submitted July 28, 2023, at the time of inspection. The report shows acres treated with MgCl2, pine tar or polymer, acres hydro-seeded, and days with wind speeds in excess of 25 mph. These reports are reviewed by DAQ inspector and are in the main source files. Only minimal fugitive dust emissions were observed coming from Kennecott’s tailing operations during this inspection and water cannons were operating throughout the site. Kennecott appeared to be in compliance with the requirements of the FDAP for the facility. Watering and salt application records have been maintained. Records include maps, amounts applied, and dates. No instances of the plan not being followed were noted since the last inspection. The FDAP is used. 6 16. All unpaved roads and other unpaved operational areas that are used by mobile equipment shall be water sprayed and/or chemically treated to control fugitive dust. The application of water or chemical treatment shall be used. Treatment shall be of sufficient frequency and quantity to maintain the surface material in a damp/moist or crusted condition. If chemical treatment other than magnesium chloride is to be used, the plan must be approved by the Executive Secretary. Records of water and/or chemical treatment shall be kept for all periods when the plant is in operation. The records shall include the following items: A. Date B. Number of treatments made, dilution ratio, and quantity C. Rainfall received, if any, and approximate amount D. Time of day treatments were made Records of treatment shall be made available to the Executive Secretary upon request and shall include a period of two years ending with the date of the request. Status: In Compliance. Unpaved roads and other unpaved operational areas used by mobile equipment are water sprayed or have applications of magnesium chloride to control fugitive dust. Ames is the contractor for the tailings area. Unpaved road inspections are conducted and recorded daily by the contractor and sprayed as needed. The source submits a quarterly report detailing what has been applied and how many acres were treated. The report shows acres treated with MgCl2, pine tar or polymer, acres hydro-seeded, and days with wind speeds in excess of 25 mph. These reports are reviewed by DAQ inspector and are in the main source files. The FDAP is used. 17. Between February 15 and November 15 of each calendar year, Kennecott shall inspect the interior surface area, unpaved roads, and exterior dike area at least once every two weeks and daily when 48 hours before a wind event, wind gusts are forecasted to exceed 25 mph for more than one hour by Kennecott's station on top of the Tailings Impoundment or the Salt Lake International airport. Status: In compliance. Daily inspections are done by the contractor as per agreement with the source. 18. On the North Tailing Impoundment Kennecott shall conduct wind erosion potential inspections monthly between February 15 and November 15. The tailings distribution system consisting of the North Tailing Impoundment shall be operated to maximize surface wetness. Wind erosion potential is the area that is not wet, frozen, vegetated, crusted or treated and has the potential for wind erosion. No more than 50 contiguous acres or more than 5% of the total North tailings area shall be permitted to have the potential for wind erosion. If it is determined that the total surface area with the potential for wind erosion is greater than 5%, or at the request of the Executive Secretary, inspections shall be conducted once every five working days. Kennecott shall immediately initiate the revised inspection schedule and the results reported to the Executive Secretary within 24 hours of the inspection. The schedule shall continue to be implemented until Kennecott measures a total surface with the potential for wind erosion of less than or equal to 5%. 7 If Kennecott or the Executive Secretary, determines that the percentage of wind erosion potential is exceeded, Kennecott shall meet with the Executive Secretary, or Executive Secretary’s staff, to discuss additional or modified fugitive dust controls/operational practices, and an implementation schedule for such, within five working days following verbal notification by either party. Status: In Compliance. Monthly estimates have been calculated and recorded to verify that no more than 5% of the total exterior surface area has been subject to wind erosion. Daily interior surface area wetness inspections have been performed and recorded. Wind warnings have been received via email. Quarterly reports have been submitted, are reviewed by DAQ, and are in the main source files. No additional requests were made by the Executive Secretary during the 12-month period preceding this inspection. The required quarterly reports contain the required information for the conditions above. 19. On the closed South Tailings Impoundment Kennecott shall conduct wind erosion potential inspections on inactive non-reclaimed areas monthly between February 15 and November 15. No more than 50 contiguous acres or more than 5% of the South Tailings impoundment tailings area shall be permitted to have the potential for wind erosion. Wind erosion potential is the area that is not wet, frozen, vegetated, crusted or treated and has the potential for wind erosion. Inactive but non-reclaimed areas are to be stabilized by chemical stabilizing agents, ponded water, sprinklers, vegetation or other methods of fugitive dust control. Ponded water is the inactive non reclaimed areas on the south impoundment where water collects (ponds) resulting in standing water and/or damp, moist, or saturated ground conditions that prevent planting equipment access and/or the establishment of stable vegetation growth. If it is determined by Kennecott or the Executive Secretary, that the total surface area with the potential for wind erosion is greater than 5% of total tailings area, or at the request of the Executive Secretary, inspections shall be conducted once every five working days. Kennecott shall immediately initiate the revised inspection schedule and the results reported to the Executive Secretary within 24 hours of the inspection. The schedule shall continue to be implemented until Kennecott measures a total surface with the potential for wind erosion of less than or equal to 5% total tailings area. If Kennecott or the Executive Secretary, determines that the percentage of wind erosion potential is exceeded, Kennecott shall meet with the Executive Secretary, or Executive Secretary’s staff, to discuss additional or modified fugitive dust controls/operational practices, and an implementation schedule for such, within five working days following verbal notification by either party. Status: In Compliance. Monthly estimates have been calculated and recorded to verify that no more than 5% of the total exterior surface area has been subject to wind erosion. No additional requests were made by the Executive Secretary during the 12-month period preceding this inspection. 20. Kennecott shall control the fugitive dust on all areas that have been closed for future tailings discharge and/or shutdown A. The fugitive dust shall be controlled by reclaiming, revegetation, and/or by another plan that has been approved by the Executive Secretary. B. If a temporary or permanent shutdown occurs that would affect any area of the Kennecott Tailings Impoundment, Kennecott shall follow the dust control procedures in Condition 20.A for all areas of the Tailings Impoundment and shall 8 submit a final dust control plan for all areas of the Tailings Impoundment and have it approved at least 60 days prior to the shutdown. All fugitive dust control plans for the Tailings Impoundment shall be submitted to the Executive Secretary, attention Major New Source Review Section, for approval. Status: In Compliance. The North Tailings Impoundment is active. The South Tailings Impoundment has been shut for several years and is fully reclaimed. Several areas are also being used to test new methods for reclaiming. The FDAP is in use. 21. Exterior tailings impoundment areas determined by Kennecott or the Executive Secretary to be sources of excessive fugitive dust shall be stabilized through vegetation cover or other approved methods. The exterior tailings surface area of the North Impoundment shall be re-vegetated or stabilized so that no more than 5% of the total exterior surface area shall be subject to wind erosion. Status: In Compliance. The contractor performs daily observations. Quarterly calculations are done and reported. Several areas are being used to test new reclamation methods. 22. On the North Tailings Impoundment, as the embankment cells are filled during continual raising of the embankment, dust shall be controlled by the inherent high water content of the hydraulically placed cyclone underflow. Portions of the embankment that are not under active construction shall be kept wet or tackified by applying chemical stabilizing agents or water pumped from the toe ditch. Newly formed exterior slopes shall be stabilized with tackifiers or vegetation. Status: In Compliance. Fugitive dust is controlled 24 hours per day through use of water trucks and cannons, application of MgCl2, pine tar and polymers, and reclamation as soon as practical. All control measures are recorded. 23. Disturbed or stripped areas of the North Tailings Impoundment shall be kept sufficiently moist during the project to minimize fugitive dust. This control, or other equivalent control methods, shall remain operational during the project cycle and until the areas have been reclaimed. The control methods used shall be operational as needed 24 hours per day, 365 days per year or until the area has been reclaimed. Status: In Compliance. Fugitive dust is controlled 24 hours per day through use of water trucks and cannons, application of MgCl2, pine tar and polymers, and reclamation as soon as practical. All control measures are recorded. Kennecott stabilizes active areas with MgCl2, pine tar, and polymer, and revegetates these areas when it becomes possible. An automated system has been installed into the water cannon system and rotates between watering areas within the required timeframe. Additionally, visual inspections and measurements estimates are made to ensure the flat face is wet and if discharge pipes/ducts should be changed. 24. On a quarterly basis, Kennecott shall summarize the following fugitive dust abatement program activities for the Executive Secretary: A. Documentation of the wind direction and speed data for days that winds exceeded 25 mph for a period greater than one hour during which no precipitation occurred. 9 B. Documentation of the inspections of the tailings surface area, including the wind erosion potential of the tailings surface area. C. Documentation showing areas of dust suppressant application and planting during the quarter. D. Quarterly reports shall be submitted to the Executive Secretary within 30 days following the end of each calendar quarter. Status: In Compliance. Quarterly reports are submitted and include all the required information. The most recent quarterly report was submitted July 28, 2023, at the time of inspection. These reports are reviewed by DAQ and copies are in the main source files. 25. Kennecott shall give periodic updates, as requested by the Executive Secretary concerning the status of the tailings impoundment. Status: In Compliance. Periodic updates are given each quarter. No additional requests were made by the Executive Secretary during the 12-month period preceding this inspection. The required quarterly reports contain the required information for the conditions above. 26. When it is determined by Kennecott or the Executive Secretary, that additional tailings dust control beyond the above should be considered or tailings Impoundment operational problems are occurring, Kennecott shall meet with the Executive Secretary, or Executive Secretary’s staff, to discuss proposed fugitive dust controls and implementation schedule within five working days after verbal notification by either party. Status: In Compliance. Periodic updates are given each quarter. No additional requests were made by the Executive Secretary during the 12-month period preceding this inspection. The required quarterly reports contain the required information for the conditions above. The company and state are aware of follow-on requirements. Records & Miscellaneous 27. At all times, including periods of startup, shutdown, and malfunction, owners and operators shall, to the extent practicable, maintain and operate any equipment approved under this AO including associated air pollution control equipment in a manner consistent with good air pollution control practice for minimizing emissions. Determination of whether acceptable operating and maintenance procedures are being used will be based on information available to the Executive Secretary which may include, but is not limited to, monitoring results, opacity observations, review of operating and maintenance procedures, and inspection of the source. All maintenance performed on equipment authorized by this AO shall be recorded. Status: In Compliance. Fugitive dust controls are in effect at all times and in accordance with the FDAP. All equipment is maintained through a tracking system which has routine, as needed, and preventative maintenance included. 10 28. The owner/operator shall comply with R307-150 Series. Inventories, Testing, and Monitoring. Status: In Compliance. Inventories have been submitted as required. 29. The owner/operator shall comply with R307-107. General Requirements: Unavoidable Breakdowns. Status: In Compliance. The source is familiar with the breakdown rule and has submitted them in the past when applicable. No breakdowns have occurred since the last inspection. AO AN105720040-20 (Power Plant) SECTION I: GENERAL PROVISIONS I.1 All definitions, terms, abbreviations, and references used in this AO conform to those used in the UAC R307 and 40 CFR. Unless noted otherwise, references cited in these AO conditions refer to those rules. [R307-101] I.2 The limits set forth in this AO shall not be exceeded without prior approval. [R307-401] I.3 Modifications to the equipment or processes approved by this AO that could affect the emissions covered by this AO must be reviewed and approved. [R307-401-1] I.4 All records referenced in this AO or in other applicable rules, which are required to be kept by the owner/operator, shall be made available to the Director or Director's representative upon request, and the records shall include the two-year period prior to the date of the request. Unless otherwise specified in this AO or in other applicable state and federal rules, records shall be kept for a minimum of two (2) years. [R307-401-8] I.5 At all times, including periods of startup, shutdown, and malfunction, owners and operators shall, to the extent practicable, maintain and operate any equipment approved under this AO, including associated air pollution control equipment, in a manner consistent with good air pollution control practice for minimizing emissions. Determination of whether acceptable operating and maintenance procedures are being used will be based on information available to the Director which may include, but is not limited to, monitoring results, opacity observations, review of operating and maintenance procedures, and inspection of the source. All maintenance performed on equipment authorized by this AO shall be recorded. [R307-401-4] I.6 The owner/operator shall comply with UAC R307-107. General Requirements: Breakdowns. [R307-107] I.7 The owner/operator shall comply with UAC R307-150 Series. Emission Inventories. [R307-150] Status: Not Observed. The power plant is in the process of being demolished. The equipment approved under this AO has been removed according to the source. SECTION II: PERMITTED EQUIPMENT II.A THE APPROVED EQUIPMENT II.A.1 Utah Power Plant 11 II.A.2 Cold Solvent Parts Washers Degreaser used for maintenance cleaners at various locations throughout the source. Estimated solvent usage 500 gal/yr. II.A.3 Wet Cooling Tower One non-contact water-cooling tower II.A.4 Natural Gas-Fired Emergency Generators North Generator rated at 1.2 MMBTU/hr (80 kW, 128 hp) South Generator rated at 1.2 MMBTU/hr (80 kW, 128 hp) II.A.5 Diesel-Fired Emergency Fire Pump Generator Rating: 175 hp Fuel: Diesel Manufacture Date: 2008 40 CFR NSPS Subpart IIII/ 40 CFR MACT Subpart ZZZZ Status: Not Observed. The power plant is in the process of being demolished. The equipment approved under this AO has been removed according to the source. SECTION II: SPECIAL PROVISIONS II.B REQUIREMENTS AND LIMITATIONS II.B.1 Plant-wide Conditions II.B.1.a Visible emissions from the following stationary sources shall not exceed the following opacity limits: A. Natural gas-fired emergency generator engines - 10% B. Diesel-fired emergency generator engine - 20% C. Cooling tower - 10% D. All other sources - 20% [R307-201] II.B.1.a.1 Opacity observations of emissions from stationary sources shall be conducted in accordance with 40 CFR 60, Appendix A, Method 9. [R307-305] Status: In Compliance. No emissions were noted from any sources during the inspection. II.B.2 Emergency Engine Requirements II.B.2.a The owner/operator shall not operate each emergency engine on site for more than 100 hours per rolling 12-month period during non-emergency situations. There is no time limit on the use of the engines during emergencies. [R307-401-8, 40 CFR 63 Subpart ZZZZ] II.B.2.a.1 To determine compliance with a rolling 12-month total, the owner/operator shall calculate a new 12-month total by the 20th day of each month using data from the previous 12 months. Records documenting the operation of each emergency engine shall be kept in a log and shall include the following: 12 A. The date the emergency engine was used B. The duration of operation in hours C. The reason for the emergency engine usage [R307-401-8, 40 CFR 63 Subpart ZZZZ] Status: Not Applicable. The power plant is in the process of being demolished. Emergency engines have been removed according to the source. II.B.2.a.2 To determine compliance with the rolling 12-month total, the owner/operator shall install a non- resettable hour meter for each emergency engine. [40 CFR 60 Subpart ZZZZ, R307-401-8] Status: Not Applicable. The power plant is in the process of being demolished. Emergency engines have been removed according to the source. II.B.2.b The owner/operator shall only use diesel fuel (e.g. fuel oil #1, #2, or diesel fuel oil additives) as fuel in the diesel-fired emergency fire pump generator engine (II.A.5). [R307-401-8] Status: Not Applicable. The power plant is in the process of being demolished. The diesel-fired emergency fire pump has been removed according to the source. II.B.2.b.1 The owner/operator shall only combust diesel fuel that meets the definition of ultra-low sulfur diesel (ULSD), which has a sulfur content of 15 ppm or less. [R307-401-8] Status: In Compliance. The only fuel ordered and delivered was ULS diesel fuel. The company has delivery bills in file. II.B.2.b.2 To demonstrate compliance with the ULSD fuel requirement, the owner/operator shall maintain records of diesel fuel purchase invoices or obtain certification of sulfur content from the diesel fuel supplier. The diesel fuel purchase invoices shall indicate the diesel fuel meets the ULSD requirements. [R307-401-8] Status: In Compliance. The only fuel ordered and delivered was ULS diesel fuel. The company has delivery bills in file. A certificate of analysis by Sinclair on June 5, 2023, indicates the fuel meets the ULSD requirement. Section III: APPLICABLE FEDERAL REQUIREMENTS 40 CFR Part 63 Subpart CCCCCC: National Emission Standards for Hazardous Air Pollutants for Source Category: Gasoline Dispensing Facilities Status: In Compliance. Throughput is below the 10,000 gallons threshold. All units are filled by contractors which have vapor recovery and certificates and are held by the company. All units are bottom fill and covers were in place. 40 CFR Part 63, Subpart ZZZZ: National Emissions Standards for Hazardous Air Pollutants for Stationary Reciprocating Internal Combustion Engines Status: In Compliance. The only generator on site is the 75 hp generator located at the tailings impoundment (AO-10572018-06). No other generators were observed as the generators associated with the power plant (AO-105720040-20) have been permanently removed. The manufacturer recommended maintenance activities are done as part of the yearly maintenance. The unit has a non-resettable hour meter and hours are logged. The generator has not operated over 100 hours during the past 12-month period. The source stated after the inspection via email that the 12-month total hours for this generator were 38 hours. 13 AREA SOURCE RULES EVALUATION: Nonattainment and Maintenance Areas for PM10: Emissions and Fugitive Emissions and Fugitive Dust [R307-309] Status: In Compliance. Minimal fugitive emissions were observed during the inspection. Refer to Condition 15 – 26 for more details. National Emission Standards for Hazardous Air Pollutants [R307-214] Status: In Compliance. This rule is satisfied through compliance with 40 CFR Part 63, Subpart ZZZZ. Refer to the Federal Requirements section for more details. EMISSIONS INVENTORY: Taken from DAQ’s emissions inventory database for 2020 (Tailings Impoundment, Analytical Laboratory, and Power Plant combined): Polluant Tons/yr A. PM10 ................... 28.10 B. PM2.5 .................... 3.43 C. SO2 ....................... 0.02 D. NOx ...................... 1.65 E. CO ........................ 1.48 F. VOC ..................... 0.54 PREVIOUS ENFORCEMENT ACTIONS: None in the past five years. COMPLIANCE STATUS & RECOMMENDATIONS: In Compliance with the conditions of AO DAQE- AN105720108-06, dated April 6, 2006 (Tailings), and AO DAQE- AN105720040-20, dated February 2, 2020 (Power Plant), at the time of inspection. The facility appears to be well maintained and operated. Required records were current and made available during the inspection and via email. HPV STATUS: Not Applicable. RECOMMENDATION FOR NEXT INSPECTION: Inspect at the regular frequency for this type of source. Hard hat, steel- toed boots, and safety glasses are required to tour the source. ATTACHMENT: None.