DWQ-2024-007425

INSPECTION SUMMARY and FINDINGS
Company Name/ Permittee:PacifiCorp Deer Creek Mine
Facility:Deer Creek Mine (Reclaimed)
Inspection Type:Compliance Evaluation Inspection (CEI)
Permit Number: UT0023604
Start Date and Time: 17 October 2024, 10:45 AM
End Date and Time: 17 October 2024, 12:00PM
Weather Conditions:Cloudy, mild, light rain ~51℉
Facility Location:~10 miles northwest of Huntington, Utah up Huntington Canyon off Utah Hwy 10
OVERVIEW
Jeff Studenka of the Division of Water Quality (DWQ) met with Peter Brinton representing the PacifiCorp Deer Creek Minefacility (DCM facility) to conduct a CEI for FY25 at the UPDES
facility referenced above. The purpose of the inspection was discussed with credentials presented, the DWQ UPDES Inspection Checklist was completed, and a facility tour was conducted
with photos collected as included herein. There were no deficiencies noted for follow up from the previous inspection conducted inFY21.
PERMIT INFORMATION
Discharge:
Receiving Waters:Deer Creek, Huntington Creek
Permitted Outfalls:002, 003
Permit Issuance Date:02/01/2020
Permit Expiration Date:01/31/2025 (permit renewal efforts ongoing)INSPECTION ACTIVITIES
Background:The former DCM facility ceased coal production in January 2015, the portals were sealed later that year, and with final reclamation completed in late 2019. The facility has
two remaining discharge points as permitted.Outfall 002 is a pipeline from the former DCM portals to discharge any future mine water directly intothe Deer Creek drainage. There have
been no discharges from Outfall 002 since the mine closed in 2015. To handle discharges from the former DCM facility’s nearby Rilda Canyon portal, a pipeline was built from Rilda Canyon
to the raw water pond at the adjacent PacifiCorp Huntington Power Plant. The pipeline was completed in late 2017. Within the raw water pond the discharge water is consumptively used
as cooling water at the plant, and thereby no discharge to surface waters occurs. However, if the power plant ceases operation or chooses not to utilize the mine water in the future,
then the water would be diverted to nearby Outfall 003 as authorized in the permit. There have been no discharges to date from Outfall 003.
Sampling and Record Keeping:As mentioned above, there have been no discharges from the facility since 2015. However, if discharges were to occur, the DCM facility would collect samples
and deliver toSGS Analytical Labs in Huntington, Utahfor all required permit parameters except for pH, dissolved oxygen, temperature, turbidity and WET biomonitoring samples.Upon any
future discharges, the facilitypersonnel would then collect the monthly and quarterly samples as per the permit requirements and measurethe pH, dissolved oxygen, temperature and turbidity
instantaneously on site as required. As a reminder, pH and dissolved oxygen samples have 15-minute holding times for the analyses as required. For WET biomonitoring, the facilitywould
likely deliver the samples same day to W.E.T. Inc. Labs in American Fork, Utah. Also as a reminder, WET biomonitoring samples are to be submitted to the lab within 36 hours and on ice
with samples temps ~6℃ upon receipt by the lab.The facilityconsistently submits the required self-monitoring information online each month thru NetDMR as appropriate.
Effluent & Flow Measurement:  At the time of the inspection, there was no discharge flow from either Outfall as expected. Outfall 003 flow would be measured with an inline flow meter
located in the nearby water diversion vault. Any flows from Outfall 002 would be measured with a bucket and stop watch to determine volumes and estimated rates. These are the primary
flow measurement devices for each outfall and with no secondary measurement capabilities currently in place.
Facility Walk Through & Discharge Information:The reclaimed DCM facility and Outfall locations were observed as well as the receiving waters of DeerCreek and Huntington Creek. There
was no evidence of any recent or prior discharges and there were no deficiencies noted during the site walk. Overall, the DCM facility appeared to be properly operated and maintained.
The facility was free of any excessive debris or trash on the day of the inspection and there was no evidence of any spills or poor housekeeping. There were no safety issues or concerns
observed during the inspection as well. Photos were collected and included herein.
DEFICIENCIES
None Observed.
RECOMMENDATIONS
Please keep DWQ informed if site conditions change, especially with regards to any future discharges as appropriate.
PHOTO LOG
Photo No. 1
Date: 10-17-2024
Description:Former Deer Creek Mine Reclamation site entrance.
Photo No. 2
Date: 10-17-2024
Description:Outfall 002 location into Deer Creek drainage.Standing water is from cliffside groundwater seeps and recent rainfall.
Photo No. 3
Date: 10-17-2024
Description:Huntington Plant raw water pond. Mine water enters in lower right corner of pic.
Photo No. 4
Date: 10-17-2024
Description:Pipeline vault with gate valve and flow meter for Outfall 003.
Photo No. 5
Date: 10-17-2024
Description:Outfall 003 close up. Note cover flange to prevent inadvertent discharges.
Photo No. 6

Date: 10-17-2024
Description:Outfall 003 discharge location looking downstream in Huntington Creek.