Document NE5Qj35G6aZwM3GV8gGGbGLbV

NPDES Compliance Inspection Report Knife River Corporation Boise, Idaho NPDES Tracking Number: #IDR053188 Inspection Date: 9/16/2024 Prepared by: CJ Langlois U.S. Environmental Protection Agency, Region 10 Enforcement & Compliance Assurance Division Water Enforcement & Field Branch Field, Data & Drinking Water Enforcement Section Inspector Signature/Date: Langlois, Curmit Digitally signed by Langlois, Curmit Date: 2024.12.10 12:22:12 -08'00' Supervisor Signature/Date: Contreras, Peter Digitally signed by Contreras, Peter Date: 2024.12.10 12:50:35 -08'00' Knife River Corporation #IDR053188 Contents I. II. III. IV. V. VI. VII. VIII. VII. IX. X. Facility Information ................................................................................... 3 Inspection Information ............................................................................. 3 Permit Information ................................................................................... 4 Enforcement Background........................................................................... 4 Inspection Chronology ............................................................................. 4 Opening Conference.....................................................................................................5 Laboratory Inspection...................................................................................................6 Site Review................................................................................................ 6 File Review................................................................................................ 7 Areas of Concern. ................................................................................................... 7 Closing Conference................................................................8 Attachment A - Aerial Image & Site Map Attachment B - Photograph Log 2 of 19 Knife River Corporation #IDR053188 [Unless otherwise noted, all details in this inspection report were obtained from conversations with Ms. Megan Winter and Mr. Jack Nygaard, a review of facility documents, and/or from observations made during the inspection.] I. Facility Information Facility Name: Knife River Corporation - Mountain West Division Facility Owner/Operator: Knife River Corporation - Mountain West Physical Address: 5450 W Gowen Rd. Boise, ID 83709 Mailing Address: 5450 W Gowen Rd. Boise, ID 83709 Lat/Long: 43.5588924 N, -116.2491686 W Facility Contacts: Megan Winter, Sustainability Coordinator Knife River - Mountain West Division Office: (208) 362-6152 Cell: (503) 890 - 9746 Email: megan.winter@kniferiver.net Jack Nygaard, MSGP Project Manager Syman Erosion Control Inc. Office: (208) 287 - 8420 Cell (208) 935-5751 Email: j.nygaard@symancompany.com Permit Number: SIC Code: #IDR053188 2951 (Asphalt Paving Mixtures and Blocks) & 3273 (Ready-Mixed Concrete) Nearest Surface Water: Fivemile Creek & New York Canal II. Inspection Information Inspection Date: September 16th, 2024 3 of 19 Knife River Corporation #IDR053188 Inspectors: CJ Langlois EPA Region 10, ECAD / WEFB / FDDWES Phone: 206-553-2739 Arrival Time: 10:30 a.m. Departure Time: 12:45 p.m. Weather: Cloudy, 68 F Purpose: To evaluate compliance with the requirements of the Clean Water Act (CWA) and the National Pollutant Discharge Elimination System (NPDES) MultiSector General Permit, Subsectors D1 & E2, for Stormwater Discharges Associated with Industrial Activity in Idaho. III. Permit Information Knife River Corporation - Mountain West is permitted under the EPA's MSGP (Multi-Sector General Permit), Subsectors D1 (Asphalt Paving Mixtures and Blocks) & E2 (Ready-Mixed Concrete). The MSGP became effective on September 29, 2021, and expires on February 28, 2026. On July 1, 2021, the Idaho Department of Environmental Quality (DEQ) became the delegated authority for the permit. Idaho DEQ is now responsible for issuing permits and assuring compliance with the permits. IV. Enforcement Background There have been no recent enforcement actions. V. Inspection Chronology This was an unannounced inspection. On September 13th, 2024, I arrived at the facility just after noon. The personnel that I needed to meet with were not present during the time of my arrival. I had planned on coming back the following Monday. On September 16th, 2024, I arrived at the facility at 1030 4 of 19 Knife River Corporation #IDR053188 a.m. and met with Ms. Winter and Mr. Nygaard inside of the main office building. I stated the reason for my visit and explained the scope of my inspection. I then presented my credentials, my business card, and a Small Business Administration (SBA) form to Ms. Winter and Mr. Nygaard. I was then led on a tour of the facility grounds while Ms. Winter and Mr. Nygaard explained the business and various operations conducted on site. After the site walk-through, we sat down in a conference room to conduct the remainder of the inspection, including documentation review. They both answered all my questions and I was not denied access to any area of the facility. The inspection at the facility lasted until approximately 12:45 p.m. VI. Opening Conference The Knife River Corporation is located in Boise, Idaho, and just to the west of Boise Airport. Operations at the Boise location have been going on for 20+ years. Current operating hours are from 7 a.m. - 5 p.m., Monday through Saturday. The facility has approximately 500 employees that work for the company. The main orders of business at the Knife River - Mountain West include ready-mix concrete production & storage, hot mix asphalt production, and equipment maintenance (inside of the shop building). The facility discharges water into Fivemile Creek, which is a tributary that runs into the New York Canal. The New York Canal is a man-made irrigation canal that is sourced from the Boise River via the Diversion Dam in Ada County. The canal ends 41 miles later at Lake Lowell in Canyon County. During the time of my inspection, Fivemile Creek was completely dry. Boise, Idaho, only receives just over 11 inches of rainfall annually (on average) and is considered a semi-arid climate. Most of the area's rainfall occurs between November and April. The facility includes a gravel pit that is located on the northern side of the property. Sand and gravel are excavated and stockpiled at the gravel pit. These aggregates are then used to manufacture batch concrete. Transit mixers (concrete trucks) that return to Knife River, after offloading concrete at various job sites, are often cleaned onsite. Aggregates are also used to blend with heated asphalt oil before loaded and hauled off to work sites. Industrial activities exposed to stormwater include asphalt batch plant operations, concrete read-mix batch plant operations, vehicle parking, concrete washout (Photo 1), aggregate storage, and loading/offloading. 5 of 19 VII. Laboratory Inspection Knife River Corporation #IDR053188 Knife River Corporation sends off their quarterly monitoring samples to Analytical Labs for analysis. They do test for pH onsite and use the Extech Instruments PH100 meter for that analysis. The State of Idaho Department of Environmental Quality established Total Daily Maximum Loads (TMDLs) for the Lower Boise River watershed for total phosphorus, sediment, and bacteria as Escherichia coli (E. coli). Knife River Corporation falls under this mandate. 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." Fivemile Creek is defined as being impaired because of the following pollutants: E. Coli Sedimentation/siltation Chlorpyrifos Dissolved oxygen (DO) VIII. Site Review Ms. Winter and Mr. Nygaard led me on a tour of the facility. A site map and aerial image appear in Attachment A and a photograph log appears in Attachment B. Knife River - Mountain West occupies approximately 40 acres of land with approximately with approximately 35 acres being exposed to precipitation. The facility is an asphalt batch plant (Photo 2) and a ready-mix concrete plant (Photo 3). There is also an equipment maintenance shop onsite along with fueling bays, an equipment parking area (Photo 4), an equipment wash area, used oil storage, and a materials storage area (Photo 5). The asphalt plant and 6 of 19 Knife River Corporation #IDR053188 ready-mix concrete plant are on the northern side of the property while the equipment maintenance area is towards the southern part of the property. The gravel pit (Photo 6) onsite is used to excavate and stockpile gravel & sand. It is usually filled with stormwater that eventually permeates the substrate below. Much of the site has been graded so that the majority of stormwater is contained onsite, but there appears to be some minor erosion (Photos 7 & 8) from stormwater runoff on the south side of the property and along Fivemile Creek (Photo 9). IX. File Review I reviewed the following records: Routine Inspection Reports - 11/10/2023, 6/7/2024, 7/19/2024, 9/19/2024 Notice of Intent (NOI) - 2021 Stormwater Pollution Prevention Plan (SWPPP) - May 6, 2021 X. Areas of Concern 1) Submission Deadline for Indicator and Benchmark Monitoring Data Section 7.3.4. of the permit states "For both indicator and benchmark monitoring, you are required to submit sampling results to EPA no later than 30 days after receiving your complete laboratory results for all monitored discharge points for each monitoring period that you are required to collect samples, per Part 4.2.1. and Part 4.2.2. If you collect samples during multiple storm events in a single quarter (e.g., due to adverse weather conditions, climates with irregular stormwater discharges, or areas subject to snow), you are required to submit all sampling results for each storm event to EPA within 30 days of receiving all laboratory results for the event. Or, for any of your monitored discharge points that did not have a discharge within the reporting period, using Net-DMR, you must report that no discharges occurred for that discharge point no later than 30 days after the end of the reporting period." There are a total of 22 non-receipt violations in 2021 & 2022. All of these parameters were reported, but were approximately one month late. There is also notation in ICIS (Integrated Compliance Information System) suggesting 7 of 19 Knife River Corporation #IDR053188 that there wasn't a discharge to sample during those timeframes. Ms. Winters mentioned that there was a different project manager for the site at that time and whom is no longer with the company. Since then, the facility has been timely with the required submissions. 2) Closing Conference A closing conference was held with Ms. Winter and Mr. Nygaard on the afternoon of September 16, 2024. I stated that no obvious areas of concern were identified over the course of the inspection and gave a brief overview of the post-inspection process. I thanked them both for their time and assistance. 8 of 19 Attachment A Site Map & Aerial Image Knife River Corporation #IDR053188 Figure 1 - Site Map taken from SWPPP 9 of 19 Knife River Corporation #IDR053188 Figure 2 - Aerial image taken from Google Maps 10 of 19 Attachment B Photo Log (Photographs were taken by CJ Langlois with an Olympus Touch TG-6.) Knife River Corporation #IDR053188 Photo 1 - Concrete washout area 11 of 19 Knife River Corporation #IDR053188 Photo 2 - Asphalt plant 12 of 19 Knife River Corporation #IDR053188 Photo 3 - Ready-mix cement plant 13 of 19 Knife River Corporation #IDR053188 Photo 4 - Equipment parking area 14 of 19 Knife River Corporation #IDR053188 Photo 5 - Materials storage area 15 of 19 Knife River Corporation #IDR053188 Photo 6 - Gravel pit with stormwater retention 16 of 19 Knife River Corporation #IDR053188 Photo 7 - Minor erosion leading into Fivemile Creek (dry) 17 of 19 Knife River Corporation #IDR053188 Photo 8 - Small area of erosion leading into Fivemile Creek (dry) 18 of 19 Knife River Corporation #IDR053188 Photo 9 - Fivemile Creek (dry) 19 of 19