Nuclear Regulatory Commission January 27, 2006 – Federal Register Recent Federal Regulation Documents

The NRC has prepared a final Environmental Assessment as its evaluation of a request by Entergy Nuclear Vermont Yankee, LLC and Entergy Nuclear Operations, Inc. (Entergy or the licensee) for a license amendment to increase the maximum thermal power at Vermont Yankee Nuclear Power Station (VYNPS) from 1593 megawatts-thermal (MWt) to 1912 MWt. This represents a power increase of approximately 20 percent for VYNPS. As stated in the NRC staff's position paper dated February 8, 1996, on the Boiling-Water Reactor Extended Power Uprate (EPU) Program, the NRC staff will prepare an environmental impact statement if it believes a power uprate will have a significant impact on the human environment. The NRC staff did not identify any significant impact from the information provided in the licensee's EPU application for VYNPS or the NRC staff's independent review; therefore, the NRC staff is documenting its environmental review in an environmental assessment. The final environmental assessment and finding of no significant impact is being published in the Federal Register. The NRC published a draft environmental assessment and finding of no significant impact on the proposed action for public comment in the Federal Register on November 9, 2005 (70 FR 68106). Two sets of comments were received as discussed below. The licensee provided three comments in a letter dated December 8, 2005 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML053500122). The first comment clarified operation of the three modes of operation of the circulating water system. Based on this comment, the NRC revised the description of the system in the ``Plant Site and Environs'' and ``Water Use Impacts'' sections of the final environmental assessment. The second comment clarified that transmission lines are owned and operated by different transmission operators, rather than Entergy as was indicated in the draft environmental assessment. Based on this comment, the NRC revised the ``Transmission Facility Impacts'' section of the final environmental assessment. The third comment provided information regarding replacement of 21 of the 22 cooling tower fan motors with higher horsepower motors. Since Entergy indicated that the conclusions in the draft environmental assessment regarding cooling tower operation (including noise) were correctly stated, no changes were made based on this comment. Mr. David L. Deen of the Connecticut River Watershed Council (CRWC) provided three comments in an e-mail dated December 9, 2005 (ADAMS Accession No. ML053500124). The first comment raised concerns that the current National Pollutant Discharge Elimination System (NPDES) permit for VYNPS places no upper bound on the temperature of the river at which the licensee must stop adding waste heat through its cooling tower discharge and that a draft amendment to this permit fails to address this shortcoming. The CRWC proposed that Entergy should not raise the ambient water temperature beyond 85 [deg]F at any point within the Connecticut River. This comment exceeds the scope of the NRC's review of the proposed EPU amendment. The purpose of the NRC's environmental assessment is to evaluate the potential impact of the proposed action (i.e., the change due to the proposed EPU). As discussed in the NRC's draft environmental assessment, Entergy has requested that the State of Vermont issue an amendment to the current NPDES permit which would allow a one-degree increase in the thermal discharge limits, for certain river water temperature ranges. Entergy stated that the NPDES permit amendment is not necessary for the proposed EPU and the licensee will comply with the current NPDES permit thermal discharge limits if the permit amendment is not granted. The current NPDES permit represents the upper bound on the current impact on the river water temperatures in the vicinity of the discharge. The NRC's draft environmental assessment found that any discharge impacts for the proposed action will be the same as the current impacts from plant operation and, as such, the NRC concluded that there will be no significant impact on the Connecticut River from VYNPS discharge due to the EPU. The CRWC comment pertains to concerns regarding lack of an upper bound temperature limit in the NPDES permit. The ``upper bound'' referenced in the NRC's draft environmental assessment refers to an upper bound on the impact of the proposed EPU. Since the CRWC comment focuses on issues regarding the NPDES permit and does not provide any information regarding the impact of the proposed EPU, no changes were made to the final environmental assessment based on this comment. The second comment from the CRWC stated that if the NPDES permit thermal discharge limits are increased, there would be harm to specific aquatic species (i.e., American shad, Atlantic salmon, spottail shiner, smallmouth bass, yellow perch, walleye, largemouth bass, fallfish, white sucker, and white perch). Similar to the first comment, since the CRWC comment focuses on issues regarding the proposed amendment to the NPDES permit and does not provide any information regarding the impact of the proposed EPU, no changes were made to the final environmental assessment based on this comment. The third comment from the CRWC questioned the NRC's draft environmental assessment statement that there are no threatened and endangered aquatic species in the Connecticut River. The CRWC stated that the dwarf wedge mussel was listed as endangered under the Endangered Species Act in 1990, and that in 1993, the U.S. Fish and Wildlife Service approved a recovery plan to attempt to reestablish populations of the dwarf wedge mussel throughout its historical range including the Connecticut River. The CRWC stated that reestablishing the population in or near VYNPS would require the presence of one of its host species, the tessellated darter. The CRWC stated that although the nearest population of the wedge mussel is relatively far north of VYNPS, since the species is endangered and depends on the tessellated darter for its survival, the tessellated darter should be included in the threatened and endangered species review for the proposed EPU. According to the U.S. Fish and Wildlife Service's 1993 recovery plan, the dwarf wedge mussel (Alasmidonta heterodon) is an endangered species located in the Connecticut River system. To assess the impact of the proposed action, the aquatic species evaluated in the draft environmental assessment were those in the vicinity of the VYNPS intake and discharge structures. The dwarf wedge mussel is not located in Windham County, Vermont and, therefore, was not included in the draft environmental assessment. The dwarf wedge mussel larvae attach to a host species for survival. One host species for the dwarf wedge mussel is the tessellated darter (Etheostoma olmstedi), which is also found in the Connecticut River system. The tessellated darter is not threatened or endangered and, therefore, was not included in the draft environmental assessment for the VYNPS EPU. As noted above, the proposed EPU does not require an increase in discharge temperature limits. Further, following implementation of the EPU, the flow rate of water being withdrawn from the Connecticut River through the intake structure would not increase, and there would not be a configuration change to the intake structure to support the EPU. Therefore, the EPU would not change existing impacts on the tessellated darter. In addition, according to Ecological Studies of the Connecticut RiverVernon, VermontReport 32, dated May 2003, the quantity of tessellated darters impinged on the VYNPS traveling screens is small compared to other impinged species. Impingement from the VYNPS intake does not significantly impact the tessellated darter population. The inter-governmental Environmental Advisory Committee (comprised of certain Vermont, New Hampshire, Massachusetts, and federal agencies) established limits for impingement of American shad (Alosa sapidissima) and Atlantic salmon (Salmo salar), and because VYNPS has not approached the impingement limits set for these species, the Vermont Agency of Natural Resources (ANR) concluded that the impingement of other species at VYNPS meets applicable laws. Entrainment of all aquatic species was monitored for over a decade beginning in 1972 and determined to be insignificant by the Environmental Advisory Committee. Entrainment was subsequently removed from the VYNPS NPDES permit. Therefore, the staff concludes that there would be no significant impact from impingement or entrainment to the tessellated darter or the dwarf wedge mussel associated with the proposed action.