Document b5GzzzYaGj1pOQDnOgdrbxqOg

EPA Region 10 Enforcement and Compliance Assurance Division Clean Water Act (CWA) Inspection Report Inspection Entry Date/Time Inspection Exit Date/Time Weather Media/Statute(s)/Program(s) Type of Inspection 09/18/2024 10:00 AM (PST) Announced: No 09/18/2024 12:45 PM (PST) Access: Granted Partly Cloudy, 62 F Water, Clean Water Act, NPDES, Industrial Stormwater CEI - Compliance Evaluation Inspection Permittee Name Facility Name Facility Owner Physical Address City/State/Zip Code County Facility GPS Coordinates Facility Mailing Address Lamb Weston, Inc. Lamb Weston, Inc. - Twin Falls Lamb Weston, Inc. 856 Russet Street Twin Falls, Idaho 83301 Twin Falls 42. 5524 N -114.4827 W 856 Russet Street, Twin Falls, Idaho 83301 FRS ID EPA/IDEQ Permit Tracking # SIC Code 110000468379 IDR053145 2037 - Frozen Specialty Food Manufacturing Inspection Contacts: Organization Name Title EPA Region 10 Jon Klemesrud Lead Inspector IDEQ - Twin Falls Brandi Lowe IPDES Compliance Officer Lamb Weston - Twin Falls Tobby Kennedy Water Process Team Leader Lamb Weston - Twin Falls Sean Stansel Plant Water Quality Manager Lamb Weston - Twin Falls Andrew Gardner Plant Manager Present in Present in Opening Conf. Closing Conf. Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes EPA Inspector Signature/Date JON KLEMESRUD Jon Klemesrud, FDDWES Digitally signed by JON KLEMESRUD Date: 2024.11.07 15:03:21 -08'00' Supervisor Signature/Date PETER CONTRERAS Peter Contreras, Chief FDDWES Digitally signed by PETER CONTRERAS Date: 2024.11.08 11:04:32 -08'00' 2024 CWA NPDES IDR053145 Inspection Report This inspection report is based on information supplied by conversations with Mr. Tobby Kennedy, Mr. Sean Stansel, Mr. Andrew Gardner, or direct observations made at the time of the inspection. This inspection report may also include information gathered from a review of EPA/Idaho Department of Environmental Quality (IDEQ) files and/or public records. SECTION I - INTRODUCTION Facility Description Lamb Weston - Twin Falls (hereinafter referred to as the "Facility") is a frozen potato processing plant and supplier of conventional and specialty potato products. The Facility is owned by Lamb Weston, Inc. and is located on approximately 25 acres within an industrial area of Twin Falls, Idaho. On-site activities include raw potato receiving/unloading, sorting, storage, washing, peeling, cutting, blanching, frying, freezing, packaging, and shipping of finished potato products. Production at the Facility occurs 24/7, for approximately 300 days of the year. There are approximately 600 employees at the Facility. Rock Creek runs along the eastern portion of the Facility. Stormwater is generally managed by a large treatment and retention system that was built in 2013. Permit Information The Facility is permitted to discharge stormwater to Rock Creek (Upper Snake River/Rock Creek watershed) under the National Pollutant Discharge Elimination System (NPDES) 2021 Multi-Sector General Permit for Stormwater Discharges Associated with Industrial Activity (MSGP). The 2021 MSGP became effective on March 1, 2021, and is set to expire on February 28, 2026. The NPDES tracking number issued to the Facility for MSGP coverage is IDR053145. Permitting authority was transferred from EPA Region 10 to Idaho Department of Environmental Quality (IDEQ) on July 1, 2021, as IDEQ became the delegated authority for General NPDES Stormwater Permits under Phase IV of the scheduled transfer. Prior to the 2021 MSGP, the Facility was covered under the previous version of the permit, the 2015 EPA MSGP. As the Facility's industrial activity falls under the standard industrial classification (SIC) code 2037, (Frozen Fruit, Fruit Juices and Vegetables), the Facility is subject to the additional requirements of Part 8, Subpart A, Sector U, Subsector U3 of the MSGP (Food and Kindred Products), including sector-specific quarterly indicator monitoring for Chemical Oxygen Demand (COD), Total Suspended Solids (TSS) and pH. As IDEQ has established Total Daily Maximum Loads (TMDLs) for the Upper Snake River/Rock Creek watershed, quarterly benchmark monitoring of stormwater discharges is required for TSS, Total Phosphorus (TP) and Escherichia coli (E. Coli). See Attachment A, 2021 Additional Monitoring Requirements Letter. Compliance/Inspection History According to file documentation, the Facility was last inspected for MSGP compliance on December 8, 2020. The inspection report noted no potential compliance concerns. Entry and Inspection Chronology I was joined on the inspection by IDEQ representative Brandi Lowe. To ensure staffing and availability, this inspection was announced just prior to our arrival. At approximately, 8:00AM on September 18, 2024, I called and left a voicemail with Mr. Shane Johnson. Mr. Johnson was previously listed as the Environmental Manager for the Facility. At approximately 8:50AM, I called Mr. Tobby Kennedy, Water Process Team Lead for Facility, Mr. Kennedy answered, and I introduced myself and discussed that I had been asked to conduct a routine on-site inspection at the Lamb Weston, Inc. Twin Falls Plant. I further explained that the inspection was to assess Page 2 of 21 2024 CWA NPDES IDR053145 Inspection Report compliance with the Facility's coverage under the MSGP. Mr. Kennedy welcomed the inspection and discussed that he would be the best contact for the inspection, as Mr. Johnson had recently retired. We agreed to begin the inspection at 10:00AM. The inspection consisted of an opening conference, a walk-through of stormwater areas and related infrastructure, a records review, and concluded with a closing conference. Photographs taken during the inspection are attached to this inspection report as Attachment B, Photograph Log. Ms. Lowe (IDEQ) and I arrived on-site at approximately 10:00AM on September 18, 2024, we signed-in as visitors at the security gate and were then greeted by Mr. Kennedy. Following our initial introduction, we were escorted to a conference room where we met with Mr. Kennedy as well as Plant Manager Mr. Andrew Gardener, and Plant Quality Manager Mr. Sean Stansel. We had initial introductions as a group and had brief opening conference where I restated the purpose/scope of the inspection. I presented my EPA credentials; we exchanged business cards, and I provided a copy of EPA's Small Business Resources Information Sheet as well as EPA's Industrial Stormwater Fact Sheet associated with "Food and Kindred Products Facilities." We continued with a brief discussion regarding confidential business information (CBI), general facility operations and recent stormwater history. During our introductions, it was discussed that Mr. Kennedy is generally the primary contact regarding MSGP implementation and reporting, including conducting routine site inspections required by the permit. It was discussed that Mr. Kennedy has been in his current position at the Facility for approximately 3-years. Mr. Stansel has been in his current position for approximately 2-years. I was accompanied throughout the inspection by Mr. Kennedy and Mr. Stansel. Mr. Gardener was present for the opening conference and briefly for our exit, following the closing conference. SECTION II - OBSERVATIONS Site Review As discussed earlier in this report, on-site activities include raw potato receiving/unloading, sorting, storage, washing, peeling, cutting, blanching, frying, freezing, packaging, and shipping of finished potato products. Industrial areas at the Facility generally include a raw product receiving areas, staging areas, a wastewater treatment area, used equipment and metal storage areas, a frozen waste loading area, a cattle feed bin area, parking areas, cooking oil unloading and storage areas and a maintenance shop area. Industrial areas are paved The Facility has identified potential pollutant sources to stormwater to generally include potato matter/slurry, cooking/fry oil, sediment, salt pesticides/rodenticides, petroleum-based lubricants/grease, isopropyl alcohol, paint/paint thinner and chemicals associated with wastewater treatment (magnesium hydroxide, hydrochloric acid, sodium hydroxide, polymers). According to Mr. Kennedy, scheduled sweeping (1/2 times a month) as well as "as needed" sweeping occurs. Catch basin cleaning is conducted by the Facility's in-house maintenance program/staff. The Facility also contracts out for a quarterly flush/clean out of the Facility's stormwater system. The quarterly cleaning is performed by Sweet's Services in Twin Falls. Examples of other best management practices (BMPs) adopted by the Facility include but not limited to minimizing exposure, good housekeeping, preventive maintenance schedule for vehicles/equipment, spill response kits, and on-site inspections. Roof drains are generally routed directly to the stormwater collection system. In the summer of 2013, the Facility installed a stormwater treatment and retention system, including a "control basin" and "overflow pond." The new stormwater system can hold approximately 500,000 gallons, there are approximately nine catch basins serving the stormwater system. The control basin at the stormwater pond Page 3 of 21 2024 CWA NPDES IDR053145 Inspection Report removes debris and floatable materials as well as provides retention time for settling. The overflow pond buffers and retains stormwater flow. In the spring of 2014, an additional treatment device (oil and grit chamber) was installed within a northern portion of the stormwater collection/treatment system. With the 2013/2014 upgrades, most outfalls were decommissioned, and stormwater management transitioned to primarily being retained on-site. There are now 3 potential outfalls (Outfall 001, Outfall 003, and Outfall 005) associated with industrial activity, Outfall 003 generally serves as the stormwater pond's overflow discharge, Outfall 001 is constructed as a bypass and/or pond discharge and would only be utilized in an emergency. Outfall 005 is the overflow from the northern oil /grit chamber. Under normal conditions, the oil/grit chamber is designed to discharge to the stormwater pond and would only discharge to Outfall 005 when the water level in the stormwater pond will no longer allow drainage from the oil/grit chamber due to the hydraulic gradient. There is also a northern outfall (Outfall 008) associated with the paved facility entrance. Walk-Through Observations: Location: Wastewater Treatment Area, Outfall 001 Observation #: OB-001 We first toured the stormwater areas surrounding the wastewater treatment area and the areas east of the main facility. The wastewater treatment area is located adjacent to Rock Creek Canyon, east of the main facility. According to the Facility's Stormwater Pollution Prevention Plan, the wastewater treatment facility pre-treats all production wastewater (generated from potato processing operations) and silt water (generated from potato washing, conveying, and sorting prior to entering the processing areas) effluent from the facility. Production wastewater is pumped from the main facility to the primary clarification and dissolved air flotation thickener flocculation (DAFT) system to an anaerobic digester. Effluent from the digester is piped to the City of Twin Falls sanitary sewer system. Wastewater from the raw product receiving system (silt water) is treated separately and then recycled back for reuse. Treated excess silt water is combined with the plant's sanitary sewage and piped to the City of Twin Falls sanitary sewer. We observed the various tanks associated with the wastewater treatment system to be covered, as well as the earthen and asphalt berm around the area. Grass/vegetation is maintained along the perimeter. Stormwater from the area generally flows into area catch basins and is directed to the stormwater collection pond/system. We observed the previous collection point for Outfall 002 (Photo 1), which now connects to the main line and collection pond/system. North of the area, we observed the discharge area for Outfall 001 (Photo 2), no discharge was observed. Outfall 001 discharges to a vegetated area along the top of Rock Creek Canyon, Rock Creek is located at the base of the canyon. According to Mr. Kennedy he was not aware of discharge/overflow since the 2013/2014 upgrade. We continued north/northwest and observed catch basins located within the areas around the main facility, south of the railroad track (Photo 3, Photo 4). Location: Stormwater Collection Pond/System Observation #: OB-002 We continued north to the stormwater collection pond/system. We observed the various components of the stormwater collection/retention system/basin, including initial screening (Photo 5), grit chamber (Photo 6) and stormwater basin (Photo 7). It was discussed that these components are also cleaned/flushed quarterly by Sweet's Services, and it was discussed the system is working as designed with no issues. We then observed the stormwater pond, which was designed for a 500-year storm event. The water level within the containment pond was observed to be minimal (Photo 8). We continued north along the stormwater pond, east of the receiving Page 4 of 21 2024 CWA NPDES IDR053145 Inspection Report area/scale. We observed one stormwater catch basin/inlet to the northeast corner of the pond within the receiving area access road (Photo 9, Photo 10). Along the west end of the stormwater pond, we observed the pond's overflow within a rip-rap area identified as Outfall 003 (Photo 11). No discharge was observed, Rock Creek is located downslope of Outfall 003 to the east, at the bottom of the canyon (Photo 12, Photo 13). According to Mr. Kennedy he was not aware of discharge/overflow since the 2013/2014 upgrade. Location: Receiving Areas, Maintenance Areas, Storage Areas Observation #: OB-003 We continued the walk-through back to the south and observed the Facility's raw product receiving areas near the main facility, including the indoor slurry loading station (Photo 14, Photo 15). Areas were observed to be generally well maintained and free of staining/debris. Mr. Kennedy discussed that catch basin covers/mats were staged and available at the catch basin locations if ever needed. We continued the tour east, through the rail car/oil tanker storage spur and observed the cooking oil unloading and storage areas (truck and rail). The area was generally well maintained, and we observed a drip collection pan in use under one car. It was discussed that the rail spur is utilized approximately once per week for oil shipping/receiving. Oil storage tanks were located within secondary containment. We continued north to the "pipe and metal storage area;" a roof overhang partially covers the storage area. We also observed the forklift "Hyster" maintenance shop, where work is conducted indoors. The area was generally clean and free of staining/debris. We observed catch basins in the surrounding area, described as catch basins #9 and #10 (Photo 16, Photo 17). It was discussed that the catch basins were recently cleaned with the recommendation of needing a high pressure washed. The recent cleaning occurred two days prior to the inspection, on September 16, 2024. Location: Northern Receiving Areas, Outfall 005, Outfall 008 Observation #: OB-004 Following our time near the forklift "Hyster" maintenance shop, we returned to the northern portion of the Facility to observe the Outfall 005 and Outfall 008 collection areas and combined discharge location. The collection area includes the primary access/receiving road and parking area. It was discussed that traffic on the access road consists of approximately 30-45 trucks a day, each truck can haul approximately 35-tons of raw product. We observed the combined discharge location for Outfall 005 and 008 (Photo 18, Photo 19). The discharge location had two effluent pipes (Outfall 005 & Outfall 008); no discharge was observed at the time of inspection. The two pipes discharge to a vegetated area along the top of Rock Creek Canyon, Rock Creek is located at the base canyon. Outfall 005 serves as the overflow for the oil/grit chamber, installed along the eastern portion of the access road (Photo 20). A single catch basin along the southern half of the primary access/receiving road is the single influent source to the oil/grit chamber. The northern half/portion of the access road is served by a northern catch basin (Photo 21), discharging exclusively as Outfall 008. SECTION III - Records Review The following records were reviewed as part of the inspection: Page 5 of 21 2024 CWA NPDES IDR053145 Inspection Report Record: Discharge Monitoring Reports (DMRs) Ref #: RR-001 As discussed earlier within this report, the Facility is subject to quarterly benchmark monitoring for TSS, TP and E. Coli. Prior to the inspection, I reviewed quarterly DMR data submitted over the past 5-years (July 2019 - July 2024). This was also completed by a review of an exceedance report generated by EPA's Integrated Compliance Information System (ICIS). The review noted only one discharge/sampling event, which occurred on October 25, 2021, from Outfall 005. As discussed earlier in this report, Outfall 005 is the overflow from the northern oil/grit chamber. Under normal conditions, the oil/grit chamber is designed to discharge to the stormwater pond and would only discharge to Outfall 005 when the water level in the stormwater pond will no longer allow drainage from the oil/grit chamber due to the hydraulic gradient. Samples from the October 25, 2021, discharge event were collected in-house, under the direction of the previous Environmental Manager and an analyzed by Magic Valley Labs, located in Twin Falls, Idaho. The discharge resulted in reported benchmark exceedances for TSS, TP, and E. Coli (summarized below). Quarter (Q): Parameter: Reported Value: Benchmark Value: Q4 2021 Total Suspended Solids 175 mg/L 52 mg/L Q4 2021 Total Phosphorus 1.33 mg/L 0.10 mg/L Q4 2021 E. Coli 406 NPM/100 mL 1730 NPM/100 mL According to Mr. Kennedy, an Additional Implementation Measure (AIM) Level 1 corrective action response was performed to address the exceedances. Actions included a contracted clean-out/vacuuming of the oil/grit chamber and stormwater system and contracted pest management for the live trapping of "Rock Chuck," within the outfall area. Post-inspection, Mr. Kennedy discussed that Outfall 005 piping has since been equipped with a plug, preventing future discharges. Record: Stormwater Pollution Prevention Plan (SWPPP) Ref #: RR-002 At the time of the inspection, I requested to review the Facility's SWPPP. Mr. Kennedy provided the Facility's SWPPP binder and discussed that the SWPPP was also publicly available online. In recognition of Mr. Kennedy's and Mr. Stansel's time/schedule, I conducted a cursory review of the SWPPP on-site, and I discussed that I would review the SWPPP fully post-inspection. The review noted that the SWPPP was developed using an EPA 2021 Industrial SWPPP template. The SWPPP was well documented and met the minimum requirements of the MSGP. The SWPPP was last certified/revised on May 17, 2023. It was noted that the Facility contacts portion within the SWPPP should be updated to address Mr. Johnson's recent retirement. It was also noted that the 2015 version of the MSGP was included within the SWPPP binder and not the 2021 version of the MSGP. Page 6 of 21 Site Inspection Reports, Visual Assessments & Annual Reports Ref #: RR-003 2024 CWA NPDES IDR053145 Inspection Report At the time of inspection, I requested to review Quarterly Site Inspection Reports, Visual Assessments and Annual Report documentation over the past 5-years (July 2019 - July 2024). Site inspection reports and visual assessments completed and are maintained within the SWPPP binder which is kept on-site. As a subsample, I reviewed site inspection reports and visual assessment documentation from the following inspections/assessments: March 28, 2024, June 28, 2024, September 10, 2024, February 9, 2023, May 31, 2023, September 26, 2023, December 7, 2023, March 30, 2022, May 31, 2022, September 19, 2022, and December 22, 2022. The records were generated using the MSGP templates and were well organized and well documented. If any control measures/BMPs were found/documented to need repair/replacement during a routine inspection, a preventative maintenance work order is created/logged with a completion confirmation (as applicable). See Attachment C, September 10, 2024, Work Order: 11496596. It was noted that for the single discharge event (October 25, 2021), the visual assessment was clear and had no signs of oil contamination, odors, floating solids, or suspended solids. Annual Reports (2019-2023) were also reviewed as part of this inspection. The 2022 Annual Report could not be located at the time of inspection, it was later determined by Mr. Kennedy that the 2022 Annual Report was previously submitted in error by Mr. Johnson. The 2022 report was resigned and provided post-inspection. SECTION IV- SAMPLING ACTIVITIES AND ANALYTICAL RESULTS No sampling was conducted for this inspection. SECTION V - AREAS OF CONCERN The presentation of Area(s) of Concern (AOC) does not constitute a formal compliance determination or violation. The following AOCs were identified as part of the inspection: AOC Reference #: AOC-1 Permit Coverage Signage Regulation and/or Permit Requirement: Section 1.3.6 of the MSGP states that "you must post a sign or other notice of your permit coverage at a safe, publicly accessible location in close proximity to your facility." "You must use a font large enough to be readily viewed from a public right-of-way and perform periodic maintenance of the sign to ensure that it remains legible, visible, and factually correct." At the time of inspection, it was discussed/observed that there was no permit coverage signage at the Facility. Mr. Kennedy discussed that he was previously unaware of the requirement (new in the 2021 MSGP) and would research signage options. AOC Reference #: AOC-2 October 25, 2021, Indicator Monitoring (pH & Chemical Oxygen Demand) Regulation and/or Permit Requirement: Table 8.U.6 of the MSGP identifies indicator monitoring requirements applicable for Subsector U3, including for Chemical Oxygen Demand (COD), Total Suspended Solids (TSS) and pH. Page 7 of 21 2024 CWA NPDES IDR053145 Inspection Report As discussed earlier in this report, as the Facility's industrial activity falls under the standard industrial classification (SIC) code 2037, (Frozen Fruit, Fruit Juices and Vegetables), the Facility is subject to the additional requirements of Part 8, Subpart A, Sector U, Subsector U3 of the MSGP (Food and Kindred Products), including sector-specific quarterly indicator monitoring for Chemical Oxygen Demand (COD), Total Suspended Solids (TSS) and pH. Quarterly benchmark monitoring of stormwater discharges is also required for TSS, Total Phosphorus (TP) and Escherichia coli (E. Coli), as the Facility discharges to the Upper Snake River/Rock Creek watershed with an established TMDL. As discussed earlier in this report, quarterly DMR data submitted over the past 5-years (July 2019 - July 2024) was reviewed as part of this inspection, the review noted only one discharge/sampling event, which occurred on October 25, 2021, from Outfall 005. It was discussed/observed that the Facility had sampled the discharge for the required benchmark monitoring parameters (TSS, TP, E. Coli), but did not also analyze for the additional indicator monitoring parameters (pH and COD) as required by the permit. Mr. Kennedy discussed that it was his understanding that the October 25, 2021, sampling event occurred under the direction of the previous environmental manager and the Facility is now prepared to sample for all required parameters in the unlikely event of a future discharge. SECTION VI - CLOSING CONFERENCE AND POST INSPECTION ACTIVITIES Closing Conference Following the Facility tour and records review, a closing conference was held with Mr. Kennedy and Mr. Stansel. I discussed my general observations, potential area of concern (AOC-1) and EPA's general compliance review process. I then thanked them for their time and cooperation with the inspection. Following the closing conference, we had brief exit discussion with Mr. Gardner in the hallway and then departed the Facility. Post-Inspection Activities Post-inspection, on November 6, 2024, I had a follow-up conversation with Mr. Kennedy via phone. Mr. Kennedy discussed that Outfall 005 piping has since been equipped with a plug preventing future discharges and the Facility will be installing permit coverage signage, per the permit language. We also discussed potential area of concern (AOC-2), Mr. Kennedy stated that it was his understanding that the October 25, 2021, sampling event occurred under the direction of the previous environmental manager and the Facility is now prepared to sample for all required parameters in the unlikely event of a future discharge. SECTION VII - LIST OF APPENDICES Attachment A - EPA 2021 Additional Monitoring Requirements Letters Attachment B - Photograph Log Attachment C - September 10, 2024, Work Order: 11496596 Page 8 of 21 2024 CWA NPDES IDR053145 Inspection Report ATTACHMENT A EPA 2021 Additional Monitoring Requirements Letter Page 9 of 21 2024 CWA NPDES IDR053145 Inspection Report UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION 10 1200 Sixth Avenue, Suite 155 Seattle, WA 98101 WATER DIVISION June 28, 2021 Reply to: Attn of: MS 19-C04 Ms. Mary Beth Miller Lamb Weston Incorporated 856 Russet Street Twin Falls, Idaho 83301 marybeth.miller@lambweston.com Re: Additional Monitoring Requirements for Lamb Weston under the National Pollutant Discharge Elimination System Multi-Sector General Permit, Permit Reference No. IDR053145 Dear Ms. Miller: The purpose of this letter is to notify you of watershed specific monitoring requirements that must be implemented at your facility to maintain permit coverage under the U.S. Environmental Protection Agency's 2021 Multi-Sector General Permit for Storm water Discharges Associated with Industrial Activity (MSGP). Based on the information provided in your Notice of Intent (NOI), if storm water from the Lamb Weston facility at 856 Russet Street in Twin Falls, Idaho (Facility) were to leave the site, it would discharge into Rock Creek. The State of Idaho Department of Environmental Quality (IDEQ) has established Total Daily Maximum Loads (TMDLs) for TP, TSS, and bacteria as Escherichia coli (E.coli) for the Upper Snake River/ Rock Creek watershed. Basis for EPA to Add Additional Requirements Part 2.2.2.1 of the MSGP, Existing Discharge to an Impaired Water with an EPA Approved or Established TMDL, states, "If you discharge to an impaired water with an EPA-approved or established TMDL, EPA will inform you whether any additional measures are necessary for your discharge to be consistent with the assumptions and requirements of the applicable TMDL and its wasteload allocation, or if coverage under an individual permit is necessary per Part 1.3.8." Specific Requirements The Facility is required to conduct storm water monitoring for TSS, TP, and E. coli following the standard benchmark monitoring procedures outlined in the MSGP at Part 4. Parameter Target Value TSS 52 mg/L Source of Value Upper Snake/Rock Subbasin TMDL (July 2000) Page 10 of 21 2024 CWA NPDES IDR053145 Inspection Report Parameter Target Value TP E. coli 0.100 mg/L 126 colony forming units /100 mL (geometric mean) with a "trigger" value of 406 colony forming units /100 mL Source of Value Upper Snake/Rock Subbasin TMDL (July 2000) and 2005 Upper Snake Rock TMDL Modification Report Upper Snake/Rock Subbasin TMDL (July 2000) and 2005 Upper Snake Rock TMDL Modification Report If you have any questions, please contact Margaret McCauley of my staff at (206) 553-1772 or by email at mccauley.margaret@epa.gov. Sincerely, Mathew J. Martinson, P.E., BCEE, Branch Chief Permitting, Drinking Water and Infrastructure Branch cc: Lance Holloway, Idaho Department of Environmental Quality 2 Page 11 of 21 2024 CWA NPDES IDR053145 Inspection Report ATTACHMENT B Photograph Log All photographs taken by Jon Klemesrud on September 18, 2024 Nikon Coolpix AW100 Page 12 of 21 2024 CWA NPDES IDR053145 Inspection Report Photograph Log - Lamb Weston - Twin Falls Photo #:01 (DSCN3908) Description: Facing south, photo of the decommissioned Outfall 002. The collection area is now routed to the main stormwater line, discharging to the collection pond. Photo #:02 (DSCN3909) Description: Facing east, photo of the approximate location of the Outfall 001 discharge area within Rock Creek/Rock Creek Canyon. Photo #:03 (DSCN3910) Description: Facing west, photo of catch basin located south of the railroad. Photo #:04 (DSCN3911) Description: Facing east, photo of drainage area south of the railroad. Page 13 of 21 2024 CWA NPDES IDR053145 Inspection Report Photograph Log - Lamb Weston - Twin Falls Photo #:05 (DSCN3912) Description: Facing north, photo of the initial screen within the stormwater collection/retention basin. Photo #:06 (DSCN3913) Description: Facing north, photo of grit chamber within the stormwater collection/retention basin. Photo #:07 (DSCN3914) Description: Facing northeast, photo of stormwater basin within the stormwater pond. Photo #:08 (DSCN3915) Description: Facing north, photo of the stormwater pond. Page 14 of 21 2024 CWA NPDES IDR053145 Inspection Report Photograph Log - Lamb Weston - Twin Falls Photo #:09 (DSCN3916) Description: Facing east, photo of northwest inlet to the stormwater collection system/pond. Photo #:10 (DSCN3917) Description: Facing southwest, photo of the north end of the of stormwater system/pond. Photo #:11 (DSCN3918) Description: Facing south, photo of stormwater Outfall 003. Overflow of the stormwater collection system/pond. Photo #:12 (DSCN3919) Description: Facing northeast, photo of Outfall 003 discharge area within Rock Creek/Rock Creek Canyon. Page 15 of 21 2024 CWA NPDES IDR053145 Inspection Report Photograph Log - Lamb Weston - Twin Falls Photo #:13 (DSCN3920) Description: Facing northeast, photo of Outfall 003 discharge area within Rock Creek/Rock Creek Canyon (duplicate photo to DSCN3919). Photo #:14 (DSCN3921) Description: Facing north, photo of catch basin within the receiving area. Photo #:15 (DSCN3922) Description: Photo of truck receiving area. Photo #:16 (DSCN3923) Description: Photo of catch basin near the Hyster (forklift) maintenance shop. Page 16 of 21 2024 CWA NPDES IDR053145 Inspection Report Photograph Log - Lamb Weston - Twin Falls Photo #:17 (DSCN3924) Description: Photo of catch basin near the Hyster (forklift) maintenance shop. Photo #:18 (DSCN3925) Description: Facing east, photo of the Outfall 008 discharge location and grit chamber overflow discharge location Outfall 005. Photo #:19 (DSCN3926) Description: Photo of the Outfall 008 discharge location and grit chamber overflow discharge location Outfall 005. Both discharging to Rock Creek/Rock Creek Canyon. Photo #:20 (DSCN3927) Description: Photo of the oil/grit chamber/separator associated with Outfall 005. Page 17 of 21 2024 CWA NPDES IDR053145 Inspection Report Photograph Log - Lamb Weston - Twin Falls Photo #:21 (DSCN3928) Description: Facing northwest, photo of the collection area and catch basin for Outfall 008. Page 18 of 21 2024 CWA NPDES IDR053145 Inspection Report ATTACHMENT C September 10, 2024, Work Order: 11496596 Page 19 of 21 2024 CWA NPDES IDR053145 Inspection Report Page 20 of 21 2024 CWA NPDES IDR053145 Inspection Report Page 21 of 21