DCL-23-034, 2022 Annual Nonradiological Environmental Operating Report

2022 Annual Nonradiological Environmental Operating Report

ML23121A130
Person / Time
Site:	Diablo Canyon
Issue date:	05/01/2023
From:	Rebel T Pacific Gas & Electric Co
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
DCL-23-034
Download: ML23121A130 (1)

Text

Trevor D. Rebel Manager, Environmental Protection Diablo Canyon Power Plant Mail code 104/5/521 P.O. Box 56 Avila Beach, CA 93424 805.545.3607 Trevor.Rebel@pge.com A member of the STARS Alliance Callaway

• Diablo Canyon

• Palo Verde

• Wolf Creek PG&E Letter DCL-23-034 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Docket No. 50-275, OL-DPR-80 Docket No. 50-323, OL-DPR-82 Diablo Canyon Power Plant, Units 1 and 2 2022 Annual Nonradiological Environmental Operating Report

Dear Commissioners and Staff,

Enclosed is the 2022 Annual Nonradiological Environmental Operating Report for Diablo Canyon Power Plant, Units 1 and 2. This report is being submitted in accordance with Subsection 5.4.1 of the Environmental Protection Plan, Appendix B of the Facility Operating License Nos. DPR-80 and DPR-82.

Pacific Gas and Electric Company makes no new or revised regulatory commitments (as defined by NEI 99-04) in this letter.

If you have questions concerning this report, please contact me at (805) 545-3607.

Sincerely, Trevor D. Rebel Date armb/50941710 Enclosure cc:

Diablo Distribution cc/enc: Mahdi O. Hayes, Senior Resident Inspector Matthew T. Keeling, Executive Officer, Central Coast Regional Water Quality Control Board Samson S. Lee, NRR Project Manager Robert J. Lewis, Acting NRC Region IV Administrator 5-1-23 m

PacHic Gas and Electric Company*

Enclosure PG&E Letter DCL-23-034 2022 ANNUAL NONRADIOLOGICAL ENVIRONMENTAL OPERATING REPORT DIABLO CANYON POWER PLANT, UNITS 1 AND 2 Pacific Gas and Electric Company April 2023

Enclosure PG&E Letter DCL-23-034 page 1 of 5

1. Introduction Pacific Gas and Electric Company (PG&E) has prepared the 2022 Annual Nonradiological Environmental Operating Report in accordance with the Environmental Protection Plan (EPP), which is Appendix B of Facility Operating License Nos. DPR-80 and DPR-82 for Diablo Canyon Power Plant (DCPP), Units 1 and 2, respectively. The report describes implementation of the EPP per the routine reporting requirements of EPP Subsection 5.4.1. PG&E remains committed to minimizing the environmental impact of operating DCPP.

2. Environmental Monitoring 2.1. Aquatic Issues Aquatic issues are addressed by the effluent limitations and receiving water monitoring/reporting requirements contained in the DCPP National Pollutant Discharge Elimination System (NPDES) permit. The NPDES permit includes applicable requirements of the California State Water Resources Control Board's Ocean Plan and Thermal Plan.

2.1.1. Routine Influent and Effluent Monitoring During 2022, DCPP submitted quarterly NPDES reports containing routine influent and effluent monitoring data and permit compliance summaries to the Central Coast Regional Water Quality Control Board (CCRWQCB). The reports were submitted electronically during the month following the end of each calendar quarter via the California Integrated Water Quality System (CIWQS), an internet database application. DCPP also submitted an annual NPDES report for 2022 to the CCRWQCB in February 2022 via the CIWQS application. The annual report contained monitoring data summaries in tabular and graphical form, and a summary of permit compliance and corrective actions, as applicable, for 2022.

2.1.2. Receiving Water Monitoring Program (RWMP)

The NPDES RWMP, required by the CCRWQCB, included the ecological monitoring, temperature measurements, and State Mussel Watch (SMW) activities.

Environmental monitoring programs have recorded biological changes in the discharge area since plant start-up. These programs monitor intertidal and subtidal communities of invertebrates, algae, and fish in the discharge cove and at stations north and south of DCPP. During 2022, environmental monitoring continued under the revised RWMP.

The revised RWMP continued historical monitoring tasks, including

Enclosure PG&E Letter DCL-23-034 page 2 of 5 temperature monitoring, SMW activities, and intertidal and subtidal surveys (with additional stations and increased sampling frequencies).

DCPP submitted the NPDES Receiving Water Monitoring Program:

2021 Annual Report (PG&E Letter No. DCL-2022-515) to the CCRWQCB and the NRC on April 28, 2022. The 2022 Receiving Water Monitoring Program Annual Report will be submitted at the end of April 2023.

During 2021, final resolution of the plant thermal discharge impacts settlement agreement was realized. A public review and comment period was completed in early 2021 for the updated settlement which had been negotiated between PG&E and the CCRWQCB during 2020.

The settlement addressed impacts on receiving waters from past and ongoing power plant cooling water discharges. The legal agreement between parties was concluded following judicial review and approval by Consent Judgment in the California Superior Court, County of San Luis Obispo. Per instructions in the consent judgment, PG&E subsequently completed payment to The Bay Foundation of Morro Bay, a third-party administrator of the settlement funds acting on behalf and at the direction of the CCRWQCB.

Regardless of the thermal discharge impacts settlement resolution, the plant NPDES permit remains under administrative extension.

Currently, DCPP is pursuing a dual track approach for decommissioning and relicensing. It is expected that permit renewal will not occur before final shutdown of plant reactor and electrical generating operations in August 2025 or final NRC approval of the DCPP operating license renewal application. Accordingly, modification of the current permit RWMP will not occur in the interim period.

2.1.3. Thermal Effects Study DCPP submitted the final thermal effects comprehensive assessment report (PG&E Letter No. DCL-98-585) to the CCRWQCB and the NRC in 1998.

2.1.4. 316(b) Studies DCPP submitted the final 316(b) report, entitled 316(b) Demonstration Report (PG&E Letter No. DCL-2000-514), to the CCRWQCB and the NRC on March 1, 2000.

Enclosure PG&E Letter DCL-23-034 page 3 of 5 2.2. Terrestrial Issues 2.2.1. Herbicide Application and Erosion Control Herbicides are used as one component of an overall land vegetation management program that includes transmission line corridors and rights-of-way. PG&E continues to use only herbicides registered by the Environmental Protection Agency and approved by state authorities, and applies them in accordance with all applicable regulations.

Another component of the vegetation management program is mastication. Mastication is utilized to reduce fuel loads, create fire breaks, maintain line clearance, and increase line of sight in rights-of-way. Mastication is a vegetation management tool that reduces ground disturbance and is effective at controlling vegetation when used in conjunction with herbicides.

PG&E continues to implement erosion control activities at the plant site and in the high voltage transmission line corridors as part of an overall land management program. These erosion control activities consist of routine maintenance and prevention efforts performed periodically on an as-needed basis, including seasonal storm activity and wildfire damage repair as applicable.

2.2.2. Preservation of Archaeological Resources A. CA-SLO-2 Site Management Archaeological site CA-SLO-2 is managed in compliance with the Archaeological Resource Management Plan (ARMP) and Operating Procedure EV1.ID2. All projects undertaken within site CA-SLO-2, or immediately adjacent, are reviewed to determine whether archaeological deposits associated with the site are present and, if so, an impact assessment is completed. PG&E would invoke the notification and mitigation procedures identified in the ARMP if a project-related impact were identified.

The annual photo-monitoring of CA-SLO-2 was conducted by the PG&E Senior Consulting Scientist for Cultural Resources on December 8, 2022, accompanied by a PG&E Senior Biologist.

The overall condition of site CA-SLO-2 remained stable through 2022 at locations away from the coastal bluff, with no discernable changes observed since the last monitoring event completed in December 2021.

Monitoring indicates that the low soldier-pile retaining wall constructed during 2018 in the west-central portion of the site along a steep road cut

Enclosure PG&E Letter DCL-23-034 page 4 of 5 is functioning as designed. Modest slumping of material beyond the retaining wall was reported following significant storms in January 2023, after the annual monitoring was completed. An assessment is pending and will be addressed in the next annual report. Location specific photographs and a monitoring summary are on file with PG&E.

Routine vegetation management was conducted along roads through the site and the foot path used to reach SLO-2 photo monitoring stations. All work was conducted with hand tools within impact to the site.

No other notable events, projects, or ARMP compliance tasks related to the management of CA-SLO-2 occurred in 2022.

B. Northern Chumash Correspondence Outreach and coordination with Northern Chumash tribes in 2022 related to the management of CA-SLO-02 was focused on planning for the eventual decommissioning of Diablo Canyon. PG&E hosted field meetings at DCPP with representatives of the Northern Chumash Tribal Council (NCTC) on March 21, 2022, and with the yak tityu tityu yak tilhini Northern Chumash Tribe of San Luis Obispo County (YTT) on July 26, 2022. Tribal representatives from both groups recommended monitoring for ground-disturbing activities at CA-SLO-2 and -61 during decommissioning. PG&Es Cultural Resource Specialist also communicated via email and telephone with the representatives of the Salinan Tribe of Monterey and San Luis Obispo Counties, and Barbareno/Ventureno Band of Mission Indians, Santa Ynez, and Tule River Indian Tribe regarding decommissioning work; including eventual removal of the Cooling Water Discharge Structure.

PG&Es Senior Consulting Scientist for Cultural Resources continues to serve as a primary point of contact for engagement with tribes concerning management of SLO-2.

3. Unusual or Important Environmental Events There were no unusual or important environmental events during 2022.

Enclosure PG&E Letter DCL-23-034 page 5 of 5

4. Plant Reporting Requirements 4.1. EPP Noncompliance There were no EPP noncompliances during 2022.

4.2. Changes In Station Design There were no changes in plant design or operation, tests, or experiments that involved an unreviewed environmental question or a change to the EPP.

4.3. Nonroutine Reports There were no nonroutine events during 2022 per the EPP; therefore, no nonroutine reports were submitted to the NRC.