DCL-20-012, Response to NRC Request for Additional Information Regarding Diablo Canyon Power Plant, Units 1 and 2 - Post-Shutdown Decommissioning Activities Report
| ML20071L136 | |
| Person / Time | |
|---|---|
| Site: | Diablo Canyon  (DPR-080, DPR-082) |
| Issue date: | 03/11/2020 |
| From: | Welsch J Pacific Gas & Electric Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| DCL-20-012 | |
| Download: ML20071L136 (6) | |
Text
Pacific Gas and Electric Company" March 11, 2020 PG&E Letter DCL-20-012 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 Docket No. 50-275, OL-DPR-80 Docket No. 50-323, OL-DPR-82 Diablo Canyon Units 1 and 2 James M. Welsch Senior Vice President Generation and Chief Nuclear Officer Oiablo Canyon Power Plant P.O. Box 56 Avila Beach, CA 93424 805.545.3242 E-Mail: James.Welsch@pge.com 10 CFR 50.82 Response to NRC Request for Additional Information Regarding Diablo Canyon Power Plant, Units 1 and 2 - Post-Shutdown Decommissioning Activities Report
References:
- 1. PG&E Letter DCL-19-077, "Diablo Canyon Power Plant, Units 1 and 2 - Post-Shutdown Decommissioning Activities Report," dated December 4, 2019 (ML19338F173)
- 2. NRC Email, "Diablo Canyon Nuclear Power Plant, Units 1 and 2 -
Request for Additional Information for Post-Shutdown Decommissioning Activities Report (PSDAR) (EPID L-2019-LRL-0004)," dated February 10, 2020 (ML20041E601)
Dear Commissioners and Staff:
In Reference 1, Pacific Gas and Electric Company (PG&E) submitted the Post-Shutdown Decommissioning Activities Report for Diablo Canyon Power Plant, Units 1 and 2. In Reference 2, the NRC requested additional information (RAI). The Enclosure to this letter provides PG&E's response to the NRC RAls.
PG&E makes no new or revised regulatory commitments (as defined by NEI 99-04),
in this submittal.
If you have any questions or require additional information, please contact Mr. Philippe Soenen, Decommissioning Environmental and Licensing Manager, at (805) 459-3701.
Sincerely,
~~--'-,<..-L -
Mes M. Welsch A
member of the STARS Alliance Callaway
- Diablo Canyon
- Palo Verde
- Wo l f Creek
Document Control Desk March 11, 2020 PG&E Letter DCL-20-012 Page 2 Enclosure cc:
Diablo Distribution cc/enc:
Scott A. Morris, NRC Region IV Administrator Lindsay N. Merker, NRC Acting Senior Resident Inspector Gonzalo L. Perez, Branch Chief, California Department of Public Health Balwant K. Singal, NRC Senior Project Manager A
member of the STARS Alliance Callaway
- Diablo Canyon
- Palo Verde
- Wolf Creek
RA/1 PG&E Letter DCL-20-012 Enclosure PG&E Response to NRC Requests for Additional Information The Diablo Canyon Nuclear Power Plant, Units 1 and 2 (Diablo Canyon) PSDAR states that PG&E plans to modify an existing rail yard, the Pismo Beach Rail Yard, to support transport of waste offsite during decommissioning. The Pismo Beach Rail Yard improvements were not considered in the PSDAR environmental evaluation. The PSDAR further states that in accordance with 10 CFR 50.82(a)(4)(i), PG&E will verify that the proposed Pismo Beach Rail Yard improvements to support decommissioning activities are bounded by previously issued environmental impact statements.
- a. Provide a basis for determining that the Pismo Beach Rail Yard improvement activities are beyond the scope of the PSDAR and do not require consideration in the PSDAR's environmental evaluation.
- b. Have the environmental impacts of the Pismo Beach Rail Yard improvement activities been considered and/or documented in previously issued environmental impact statements? If so, please provide full citations to such documents and provide a discussion supporting the conclusion that all reasonably foreseeable impacts from the improvement project are bounded.
- c. Clarify the timeframe for initiating and completing the proposed rail yard improvements.
PG&E Response to RAI 1 The Pismo Beach Rail Yard improvement activities are within the scope of the Post-Shutdown Decommissioning Activities Report (PSDAR) and require consideration in the environmental evaluation; however, Pacific Gas and Electric Company (PG&E) does not have detailed environmental impact information at this time. In addition, the scope of the Pismo Beach Rail Yard improvement activities has not been reviewed in previously issued environmental impact statements.
As discussed on pages 5 and 23 of the PS DAR, "[i]n accordance with 10 CFR 50.82(a)(4)(i), PG&E will verify that the decommissioning activities for the Pismo Beach Rail Yard improvements are bounded by previously issued environmental impact statements or seek appropriate regulatory approval if needed." Prior to implementing the Pismo Beach Rail Yard improvements, which are currently scheduled to begin in 2030 and finish in 2032, PG&E will ensure the activity complies with 10 CFR 50.82(a)(6)(ii) and notify the NRG of changes to the PSDAR as required by 10 CFR 50.82(a)(7).
RA/2 The PSDAR states that PG&E has determined that onsite land to be used to support decommissioning activities has been previously disturbed. To support the new power load requirements, PG&E will use approximately 10 miles of existing transmission lines and will install approximately 6 miles of new 12-kV distribution line. Will undisturbed Page 1 of 4
PG&E Letter DCL-20-012 Enclosure land be affected to support the new power load requirements? Identify (number of acres and location) any new land that would be permanently or temporarily disturbed.
PG&E Response to RAI 2 PSDAR Section 5.1.1. states "PG&E will use approximately 10 miles of existing transmission lines (repowered) and will install approximately six miles of new 12-kV distribution line (expected to be installed beneath an existing 70-kV line). Existing towers and poles along an existing right-of-way will b~ used; however, several poles are likely to require replacement to provide the required separation from ground and the different voltages, and some of the existing transmission towers will need to be modified to accommodate the physical load changes resulting from the new configuration of the transmission lines."
Ground disturbance could result from, and has been evaluated for each of the following:
- 1. Existing transmission tower modifications: PG&E has determined the modifications to the transmission towers will not result in ground disturbances.
- 2. Replacement of existing poles: No more than five existing poles will be replaced, resulting in up to 2,000 square feet (approximately 0.05 acres) of ground disturbance total. Because the area affected at each pole will be within an existing right-of-way, where ground has been previously disturbed during initial line placement and maintenance, associated ground disturbance will be minor.
RA/3 The decommissioning GEIS (NUREG-0586, Supplement 1 ), states that noise levels below 60 to 65 dBA are considered to be insignificant and that the sources of noise would be sufficiently distant from critical receptors outside the plant boundaries that the noise would be attenuated to ambient levels and therefore scarcely noticeable. The PSDAR identifies that offsite power supply modifications will require helicopter support and the effective perceived noise level for the helicopter can range from 80-100 decibels. Identify (if any) nearby sensitive noise receptors (residents, schools, hospitals), and discuss PG&E's basis for concluding that the noise levels that can range from 80-100 decibels are not expected to present an audible intrusion to the nearby sensitive noise receptors.
PG&E Response to RAI 3 As stated in the PSDAR, for the offsite power modifications, PG&E will use approximately 10 miles of existing transmission lines (repowered) and will install approximately 6 miles of new 12-kV distribution line (expected to be installed beneath an existing 70-kV line). The proposed offsite power route begins at the Diablo Canyon Power Plant (DCPP) site, traverses the Irish Hills, and terminates at a PG&E substation adjacent to California Highway 1. The route passes over one arterial (2-lane) roadway, Los Osos Valley Road.
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Residences PG&E Letter DCL-20-012 Enclosure The Irish Hills are a rural area with mountainous, rugged terrain and a few single residences dispersed over the range. Residences are approximately a minimum distance of 0.5 miles from the proposed offsite power route except as follows:
Near the Los Osos Valley Road crossing, as the population density temporarily increases, the proposed offsite power route will be approximately 0.1 miles from residences.
Near the PG&E substation, where there is a small residential area, the proposed offsite power route will be adjacent to residences.
Due to attenuation from the distance and terrain, noise from helicopters would drop below 65 dBA (A-weighted sound levels) for the residences greater than 0.1 miles from the proposed offsite power route.
Due to the flat terrain surrounding the PG&E substation, PG&E does not plan to use helicopters to support the modifications for this portion of the route. Therefore, noise from helicopters is not a concern and noise levels would remain below 60 to 65 dBA.
Other Sensitive Noise Receptors Other closest sensitive noise receptors (e.g., hospitals, schools, etc.) are greater than 2.5 miles away from the proposed offsite power route. Due to attenuation from the distance and terrain, noise from helicopters over the Irish Hills would drop well below 65 dBA for the closest sensitive noise receptor.
Based on the above, PG&E concludes the noise levels from offsite power modifications are not expected to present an audible intrusion on the surrounding community and environment and are bounded by the DCPP Final Environmental Statement.
RA/4 On September 18, 2009, the National Marine Fisheries Service (NMFS) issued a biological opinion under the authority of the Endangered Species Act of 1973, as amended (ESA), for Diab/a Canyon (ADAMS Accession No. ML063000348). The opinion pertains to four species of sea turtles: green (Chelonia mydas), leatherback (Dermochelys coriacea), loggerhead (Caretta caretta), and olive ridley (Lepidochelys olivacea). The opinion allows for the incidental take of specified numbers of these species subject to PG&E's adherence to three reasonable and prudent measures (RPMs) and nine terms and conditions (T&Cs). Please explain how PG&E will continue to adhere to these RPMs and T&Cs during the decommissioning period.
PG&E Response to RAI 4 During operations, PG&E will continue to implement the reasonable and prudent measures and terms and conditions outlined in the September 18, 2009, Biological Opinion.
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PG&E Letter DCL-20-012 Enclosure However, upon permanent cessation of operations, it would be appropriate to amend the Biological Opinion to be more relevant to decommissioning activities. In accordance with 50 CFR 402.16(a), the effect of DCPP decommissioning activities on listed species or critical habitat was not previously considered in the Biological Opinion.
Therefore, PG&E is requesting that the NRC reinitiate consultation with the NMFS with respect to the Biological Opinion for the DCPP Decommissioning Project. PG&E would like to discuss with the NRC the approach and schedule for this consultation.
RA/5 In addition to sea turtles, the federally endangered black abalone (Haliotis cracherodii) occurs in Diab/a Canyon's intake and discharge coves and nearby water~. The surrounding intertidal zone is also designated as critical habitat for this species. The federally threatened southern sea otter (Enhydra /utris nereis) also occurs in intake and discharge coves. PG&E states in its PSDAR (p. 34) that:
Direct and indirect impacts to these protected species may occur during demolition of the discharge structure, including direct mortality of individual species, as well as impacts from runoff, sedimentation, dust generation, or noise disturbance.
Causing injury to or mortality of federally listed species is strictly prohibited under Section 9 of the ESA. Please explain how PG&E would obtain the necessary permits under either ESA Section 7 or ESA Section 10 to exempt the incidental take of these species during the decommissioning period.
PG&E Response to RAI 5 PG&E plans to obtain the necessary permits under Section 7 of the Endangered Species Act (ESA) for potential incidental take of federally listed species.
On November 19, 2019, PG&E met with representatives of the United States Fish and Wildlife Service (USFWS) to discuss the DCPP Decommissioning Project. During the meeting, USFWS staff identified that they would like to have the NRC: (1) serve as the Federal Lead Agency to carry out review under the National Environmental Policy Act (NEPA); and (2) consult with the USFWS pursuant to Section 7 of the ESA. USFWS affirmed this again during a tour of the DCPP on January 27, 2020.
During a tour of DCPP on February 28, 2020, a representative of the NMFS agreed it would be preferable to have the NRC serve as the NEPA lead agency and consult with both the NMFS and USFWS under Section 7 of the ESA regarding potential take of special status species during DCPP Decommissioning.
Therefore, PG&E requests the NRC serve as the NEPA lead agency for the DCPP Decommissioning Project and consult with both the USFWS and the NMFS regarding potential incidental take of federally listed species. PG&E would like to discuss the approach and schedule for this with the NRC.
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