DCL-20-036, 2019 Annual Non-Radiological Environment Operating Report

2019 Annual Non-Radiological Environment Operating Report

ML20120A624
Person / Time
Site:	Diablo Canyon
Issue date:	04/29/2020
From:	Gerfen P Pacific Gas & Electric Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
DCL-20-036
Download: ML20120A624 (7)

Text

Paula Gerfen Site Vice President Diablo Canyon Power Plant Mail code 104/5/502 P.O. Box 56 Avila Beach, CA 93424 805.545.4596 Internal: 691.4596 Fax: 805.545.4234 A member of the STARS Alliance Callaway

• Diablo Canyon

• Palo Verde

• Wolf Creek April 29, 2020 PG&E Letter DCL-20-036 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 2019 Annual Nonradiological Environmental Operating Report

Dear Commissioners and Staff,

Enclosed is the 2019 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.

PG&E 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 Mr. David Cortina, Chemistry and Environmental Operations Manager, at (805) 545-3517.

Sincerely, Paula Gerfen dqmg/50941710-7 Enclosure cc:

Diablo Distribution cc/enc: Scott A. Morris, NRC Region IV Administrator Christopher W. Newport, NRC Senior Resident Inspector Matthew T. Keeling, Executive Officer, Central Coast Regional Water Quality Control Board Balwant K. Singal, NRR Senior Project Manager Pacilic Gas* and Electric Company*

Enclosure PG&E Letter DCL-20-036 2019 ANNUAL NONRADIOLOGICAL ENVIRONMENTAL OPERATING REPORT DIABLO CANYON POWER PLANT, UNITS 1 AND 2 Pacific Gas and Electric Company April 2020

Enclosure PG&E Letter DCL-20-036 page 1 of 5

1. Introduction Pacific Gas and Electric Company (PG&E) has prepared the 2019 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 2019, 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 2019 to the CCRWQCB in February 2020 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 2019.

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 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 2019, environmental monitoring continued under the revised RWMP.

The revised RWMP continued historical monitoring tasks, including

Enclosure PG&E Letter DCL-20-036 page 2 of 5 temperature monitoring, State Mussel Watch activities, and intertidal and subtidal surveys (with additional stations and increased sampling frequencies).

The NPDES permit remains under administrative extension. In 2000, DCPP reached a tentative agreement with CCRWQCB staff that addressed current and future impacts on receiving waters from ongoing power plant cooling water discharge. This agreement, and the associated NPDES permit renewal application, did not receive the expected approvals from the CCRWQCB in July 2003. Currently, final resolution of outstanding issues related to receiving water impacts, as well as NPDES permit renewal, remain pending. Based on the tentative agreement, future receiving water monitoring requirements will be significantly reduced or potentially eliminated upon approval of a renewed NPDES permit. Power plant wastewater discharge effluent monitoring would continue under a revised NPDES permit.

DCPP submitted the NPDES Receiving Water Monitoring Program:

2018 Annual Report (PG&E Letter No. DCL-2019-512) to the CCRWQCB and the NRC on April 30, 2019. The 2019 Receiving Water Monitoring Program Annual Report will be submitted at the end of April 2020.

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.

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. The company 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.

Enclosure PG&E Letter DCL-20-036 page 3 of 5 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-ways. 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 completed on December 11, 2019, by the PG&E Senior Cultural Resource Specialist.

The overall condition of site CA-SLO-2 remained stable in locations away from the coastal bluff, with only minor changes observed in the interim following the last monitoring event completed in December of 2018. 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 is functioning as designed. No new earthen slumping or erosion was observed, and the impacted location has revegetated in the interim. Location specific photographs and a monitoring summary are on file with PG&E.

One notable event in the management of CA-SLO-2 relates to exploratory archaeological testing initiated in late August 2019 to assess potential impacts for the planned replacement of an existing 23 kV transmission system guyed tubular steel pole (TSP) located

Enclosure PG&E Letter DCL-20-036 page 4 of 5 within the site. A monitor from the yak titu titu yak tiłhini Northern Chumash Tribe was present on site to observe fieldwork.

A 1 by 2 square meter control unit and column sample were excavated approximately 12-feet southwest of the existing TSP, at the location of the proposed new TSP foundation. A significant collection of artifacts and faunal remains were recovered during field screening of excavated sediments. Further exploration at the location stopped on September 4, 2019, when human remains were discovered in a side wall of the excavation unit, nested within the proposed bore hole for the new TSP foundation.

In compliance with CA Health and Safety Code section 7050.5, the San Luis Obispo County Coroner (Case #1909-07386) was notified of the discovery at 11:37 a.m. on the date of discovery. The County Coroner makes the determination as to whether the remains are of Native American ancestry and verifies the discovery site is not a modern crime scene. Having determined the remains were prehistoric Native-affiliated based on the context of the discovery, the County Coroner referred the matter to the California Native American Heritage Commission (NAHC). The NAHC assigns a Most Likely Descendant (MLD) to work with the land owner (PG&E) on the disposition of the remains. The NAHC designated the Chair Person of the yak titu titu yak tiłhini Northern Chumash Tribe of San Luis Obispo County as the MLD.

PG&Es Senior Cultural Resource Specialist worked closely with the MLD and related tribal members to provide for a dignified reburial of the human remains and proximal midden. The MLD supported the retention of some artifacts and ecofacts for non-destructive analysis and reporting. These items will be reburied via a 4" diameter vertical pipe that was placed temporarily within the former excavation unit to facilitate future reburial of materials and extraction of the pipe. Reporting specific to the archaeological testing and an archaeological site record update remains in progress.

The project planning and engineering teams for the TSP replacement are currently analyzing alternatives that would meet the safety and reliability requirements for the 230 kV system, while lessening or avoiding impacts to the CA-SLO-02 archaeological site.

B. Northern Chumash Correspondence Outreach and coordination with the yak titu titu yak tiłhini Northern Chumash Tribe of San Luis Obispo County in 2019 related to the management of CA-SLO-02 was focused on the 230 kV TSP

Enclosure PG&E Letter DCL-20-036 page 5 of 5 replacement project (reference previous section). PG&Es Senior Cultural Resource Specialist served as the primary point of contact for engagement with the tribe in the initial project planning phases during archaeological fieldwork, in response to the discovery of human remains, and in the planning process going forward for project alternatives. The Tribe will continue to be involved as alternatives are explored and ultimately implemented. This engagement will be in addition to other on-going projects and initiatives on the Diablo Lands outside of CA-SLO-02, which require tribal outreach and coordination.

3. Unusual or Important Environmental Events There were no unusual or important environmental events during 2019.

4. Plant Reporting Requirements 4.1. EPP Noncompliance There were no EPP noncompliances during 2019.

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 2019 per the EPP; therefore, no nonroutine reports were submitted to the NRC.