Text

Annual Environmental Protection Plan Operating Report for 2015
	ML16126A222
Person / Time
Site:	Millstone
Issue date:	04/28/2016
From:	Stanley B; Dominion Nuclear Connecticut
To:	; Document Control Desk, Office of Nuclear Reactor Regulation
References
	16-165
	Download: ML16126A222 (11)
	v • d • e

Dominion Nuclear Connecticut, Inc.

Rope Ferry Rd., Warerford, CT 06385 Mailing Address: P.O. Box 128 Waterford, CT 06385

<lorn.com APR 2 8 2016 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555-0001 DOMINION NUCLEAR CONNECTICUT, INC.

MILLSTONE POWER STATION UNIT 3 2015 ANNUAL ENVIRONMENTAL PROTECTION PLAN OPERATING REPORT Serial No.

MPS Lic/AVM Docket No.

License No.16-165 RO 50-423 NPF-49 In accordance with Section 5.4.1 of the Environmental Protection Plan (EPP), Appendix B to the Millstone Power Station Unit 3 Operating License, Dominion Nuclear Connecticut, Inc. hereby submits the Annual Environmental Protection Plan Operating Report (AEPPOR), describing implementation of the EPP for the previous year. transmits information for the period of January 1, 2015 to December 31, 2015.

Should you have any questions regarding this report, please contact Mr. Thomas G. Cleary at (860) 444-4377.

Sincerely,

~~~

Brandford L. Stanley Director, Nuclear Station Safety and Licensing

Enclosures:

1 Commitments made in this letter: None.

cc:

U. S. Nuclear Regulatory Commission Region I 2100 Renaissance Blvd, Suite 100 King of Prussia, PA 19406-2713 R. V. Guzman Serial No.16-165 2015 Annual Environmental Protection Plan Operating Report Page 2 of 2 NRC Project Manager Millstone Units 2 and 3 U.S. Nuclear Regulatory Commission One White Flint North, Mail Stop 08 C2 11555 Rockville Pike Rockville, MD 20852-2738 NRC Senior Resident Inspector Millstone Power Station MILLSTONE POWER STATION UNIT 3 Serial No.16-165 Docket No.

50-423 License No. NPF-49 2015 ANNUAL ENVIRONMENTAL PROTECTION PLAN OPERATING REPORT

JANUARY 1-DECEMBER 31, 2015 MILLSTONE POWER STATION UNIT 3 DOMINION NUCLEAR CONNECTICUT, INC. (DNC)

2015 Annual Environmental Protection Plan Operating Report (AEPPOR) 1.

Introduction:

This report covers the period January 1, 2015 through December 31, 2015. During 2015, Millstone Power Station Unit 3 (MPS3) operated near full generating capacity (99.04% ). Capacity factor for Cycle 17 to date (beginning Nov 17, 2014 though Dec 31, 2015) was 98.99%.

As required by the MPS3 Environmental Protection Plan (EPP), Appendix B to the MPS3 Operating License, this AEPPOR includes:

summaries and analyses of the results of environmental protection activities, a list of EPP noncompliances, a list of all changes in station design or operation which involved a potentially significant unreviewed environmental question, and a list of non-routine reports, describing events that could have resulted in significant environmental impact.

2. Environmental Protection Activities:

2.1 Annual National Pollutant Discharge Elimination System (NPDES) Report of Ecological Monitoring (EPP Section 4.2).

Section 1 O(A) of Millstone Power Station's (MPS) NPDES permit (the Permit),

as issued to Dominion Nuclear Connecticut, Inc. (DNC) by the Connecticut Department of Environmental Protection (now the Department of Energy and Environmental Protection, or DEEP) on September 1, 2010, requires, among other things, continuation of biological studies of supplying and receiving waters. These studies include analyses ofintertidal and subtidal benthic communities, finfish communities, entrained plankton, lobster populations, and winter flounder populations. Section 1 O(A)(2) of the Permit requires an annual report of these studies to be sent to the DEEP Commissioner on or before July 31 of each year. The latest report that fulfills these requirements, "Annual Report 2014 - Monitoring the Marine Environment of Long Island Sound at Millstone Power Station, Waterford, Connecticut" (Annual Report), dated July 2015, presents results from studies performed during construction and operation of MPS, emphasizing those of the latest sampling year.

Characteristics of and changes to the biological communities noted in these studies are summarized in the Executive Summary section of the Annual Report, which is attached as part of this report.

2.2 Effluent Water Quality Monitoring:

Se_ctions __ 1 and _5 of _the Permit _require monitoring and recording of various water quality parameters at MPS intakes and at multiple monitoring points within the plant, including outfalls of each unit to the effluent quarry, and outfall of the quarry to Long Island Sound. Section 8 of the Permit requires that a monthly report of this monitoring be submitted to the DEEP. The report that fulfills these requirements, the "Monthly Discharge Monitoring Report" (DMR),

includes discharge data from all MPS units. Consistent with prior annual AEPPOR submissions, water flow, temperature, pH, and chlorine data pertaining to MPS3 are summarized in Table 1.

2015 AEPPOR Page 1 of 3

Each monthly DMR identifies NPDES permit exceedances (i.e., events where a parameter value was beyond permitted limits) or exceptions (i.e., events where Permit conditions were not met) for the month. During 2015, there were no exceedances or exceptions associated with any discharge associated with MPS3.

2.3 Air Program - Compliance Monitoring On November 19, 2015, the Station determined that the run time hour meter on the MPS3 'A' Emergency Diesel Generator does not advance when the engine is run in "maintenance mode", i.e., when the generator's field is not energized (flashed), allowing the engine to run unloaded. As a result of this electrical alignment, the hour meter does not advance. This design condition has existed since the engines were initially installed, and is not the result of an equipment failure. 40 CFR 63 Subp~rt ZZZZ and the MPS DEEP Title V Operating permit for sources of air pollution require the use of hour meters for compliance recordkeeping and reporting. Failure to accurately monitor engine use resulted in incorrect reporting of engine hours, fuel use, and emissions, and constituted a "Failure to Comply with local, state, and federal statutes, regulations, and permits... " (from the Title V permit), but did not cause any adverse environmental impact. Subsequent corrective actions included the adoption of specific procedures to ensure that plant logs clearly note any operating time in maintenance mode, and an engineering request to permanently resolve the issue is being processed. All 2015 records have been amended to account for the maintenance mode hours.

2.4 NPDES Permit Renewal A complete application for reissuance of the MPS NPDES permit was due to CTDEEP by March 4, 2015. A team was established and milestones scheduled to ensure that a completed permit application was submitted to the DEEP in advance of the regulatory deadline. The permit application was submitted on February 6, 2015, and the DEEP issued a Notice of Sufficiency on March 6, 2015; therefore, _the permit is administratively continued and in effect until its reissuance. DEEP initiated a technical review of the application during the second half of 2015 and, as part of the process, submitted letters requesting additional information dated July 9, 2015 and October 20, 2015.

Responses to the DEEP requests were developed and submitted by letters dated September4, 2015, October 20, 2015 and December 17, 2015.

3. Environmental Protection Plan (EPP) Noncompliances:

No EPP noncompliances were identified for MPS3 in 2015.

4. Environmentally Significant Changes to Station Design or Operation:

No MPS3 design change records or system operating procedure changes initiated during 2015 included a determination that a significant unreviewed environmental impact could occur.

5. Non-Routine Reports of Environmentally Significant Events:

No MPS3 events in 2015 involved a situation that could result in a significant environmental impact.

2015 AEPPOR Page 2 of 3

No MPS3 events in 2015 involved a situation that could result in a significant environmental impact.

2015 AEPPOR Page 3 of 3

Table 1. MPS3 NPDES data summary, Jan 1-Dec 31, 2015. Selected water quality parameters for MPS3111*

2015 October November December Notes:

Maximum Discharge Flow (106 gpd}

Discharge SWS FAC (ppm} -

(1)

Parameters are measured at MPS3 discharge (DSN OOlC), except for TRC (total residual chlorine), which is measured at MPS discharge (quarry cuts; DSN 001-1), and SWS FAC (service water system free available chlorine), measured at the reactor plant component cooling water system heat exchangers (DSN OOlC-5).

2015 AEPPOR Page 4 of 3

Attachment to the 2015 Annual Environmental Protection Plan Operating Report January 1 - December 31, 2015 Executive Summary Section of "Annual Report 2014 --Monitoring the Marine Environment of Long Island Sound at Millstone Power Station, Waterford, Connecticut" dated July 2015

Executive Summary-2014 Environmental Monitoring Annual Report Rocky Intertidal Studies Rocky intertidal monitoring studies during 2014 continued to document ecological changes to the shore community near, and associated with, the Millstone Power Station (MPS) thermal discharge. These changes are not widespread, and remain restricted to approximately 150 m of shore-line on the east side of the power station discharge to Long Island Sound (LIS).

The total number of algal species identified in 2014 was 85, well within the range of annual totals for previous study years (73-99).

As in previous years, seasonal shifts in occurrence of annual algal species were noted at Fox Island-Exposed (FE) during 2014. These shifts included abbreviated season for cold-water species (e.g., Monostroma grevillei, Spongomorpha arcta, and Dumontia contorta) and extended season for warm-water species (e.g.,

Grinnellia americana, Dasya baillouviana, and Bryopsis hypnoides). Similar shifts have been observed in most years since Unit 3 began operation (1986), with the exception of the extended shutdown of all MPS Units from March* 1996 to June 1998, when seasonality of these species at FE was more typical of other sites.

Thermal effects on dominant species' abundance and distribution patterns were also evident at FE in 2014, and most apparent in the low intertidal zone. Seasonally high abundance of Hypnea musciformis, a species observed for the first time in 2001, and expanded populations of Sargassum filipendula, Corallina officinalis, and Gelidium pusillum now characterize the lower shore community at FE. Neosiphonia harveyi has maintained a perennial population at FE in 2014; but occurred mainly as a summer annual at sites unaffected by MPS.

Ascophyllum nodosum growth, represented as the most recent internodal length, was greatest at Fox Island in 2014, but continued to demonstrate no clear relationships among monitoring sites, or correlation with station operating conditions, indicating that the thermal plume from MPS has had little effect on local populations.

Natural influences of other factors, -such as ambient temperature conditions, storms and wave action, nutrients and light, play the dominant role in determining Ascophyllum growing conditions in the Millstone area.

The rocky intertidal monitoring program has also documented regional patterns and modifications to shore communities umelated to MPS operation. These include the introduction to the region of three exotic red algae (Antithamnion pectinatum in 1986, Grateloupia turuturu in

2004, and Dasysiphonia (formerly Heterosiphonia) japonica in 2010), decreases in barnacle abundance in recent years, and long-term increases in abundance of the common seaweeds Fucus vesiculosus and Chondrus crispus.

Eelgrass Eelgrass (Zostera marina L.) was monitored at three locations in. the vicinity of MPS.

Data from 2014 surveys indicated that the two study sites nearest to the MPS thermal plume* (Jordan Cove and White Point) supported healthy and expansive eelgrass populations, consistent with results since the study began in 1985.

While there has been moderate variability in abundance and distribution over the entire study period at these two sites, this variability was not related to MPS operation.

Both predicted and measured thermal input to these sites from the cooling water discharge is at most minimal ( <

1°C above ambient conditions) and well below levels considered stressful to eelgrass.

By comparison, high eelgrass population variability has been observed in the Niantic River, where complete and often sudden eelgrass bed losses were documented on six separate occasions prior to 2014. Data from the 2014 survey show recolonization of some eelgrass beds in the Niantic River.

Because the Niantic River is located well away from any influence of the MPS thermal plume, eelgrass population fluctuations there must be related to environmental factors such as increasing ambient seawater temperatures, disease, increased turbidity, and waterfowl grazing.

Results from this monitoring therefore suggest that fluctuations in eelgrass populations observed at sites in the Niantic River are due to changes in local and regional environmental conditions and not to MPS operation.

Lobster Studies Impacts associated with recent MPS operations on the local lobster population were assessed by comparing results of the 2014 study year to data collected from 1978 through 2013. Emphasis has been placed on assessing long-term trends in the abundance and population characteristics of lobsters collected in the Millstone Point area.

Throughout LIS, the lobster population was stable or increasing from 1978 through 1999. Commercial lobster catches in LIS precipitously declined from 2000 to 2014.

In this study, lobsters in the MPS area showed a similar trend, with abundance indices (total catch and CPUE)

>74% lower in research pots and >99% lower in trawls during the past three years (2012-2014), compared to highest levels in the 1990s. Declines in pot and in trawl Executive Summary

catches were unrelated to.MPS operations and attributed to an increase in mortality associated with ambient seawater temperature rise and temperature mediated stressors that include a shell disease affecting lObster populations from eastern LIS to the Gulf of Maine.

Declines in the abundance of legal-size lobsters were attributed in part to the outbreak of shell disease and to a nearly 5 inm increase in the minimum legal-size since 1978. Recent reductions in landings oflegal-size lobsters harvested by commercial lobstermen in eastern LIS coincided with declines observed in this study, and lobster catches remained severely depressed in other areas of LIS since the lobster die-off observed in 1999.

Long-term trends observed in lobster population characteristics over the past three decades (growth, female maturity, and egg-bearing lobsters) appear related to warmer ambient seawater temperatures and/or the recent outbreak of shell disease, and not.MPS operation. Increased ambient water temperature may be responsible for the increased susceptibility and transmission of diseases affecting lobsters in LIS, which is at the southern boundary of their range of distribution in nearshore waters.

Recent research suggests that ocean acidification may also exacerbate shell disease.

The number of lobster larvae entrained through the

.MPS cooling water systems was highly variable and low in recent years, due to low adult lobster abundance and low larval densities throughout LIS. Impacts associated with impingement of lobsters at.MPS have been greatly reduced by the use of aquatic organism return systems at Units 2 and 3., which return impinged lobsters to Niantic Bay.

Benthic Infauna Benthic infauna} monitoring documented long-term trends in sediment characteristics at all the subtidal sites in the vicinity of.MPS. At the effluent station (BF), the sedimentary environment remains coarse, with low

~ilt/clay which is related to discharge of cooling water into LIS at the Quarry cuts. Sediments at the intake station (IN) were consistent with -sediment characteristics prior to dredging during.MPS Unit 3 construction.

Sediments at Jordan Cove (JC) have stabilized following an earlier siltation event when increased water flow from the discharge after startup of

.MPS Unit 3 scoured fine sediments surrounding BF and deposited them at JC. Sedimentary characteristics at the reference site at Giants Neck (GN) were similar to previous years' observations and continued to reflect natural variability unrelated to.MPS.

The 2014 infauna} communities at all sampling sites continued to respond to sedimentary environments.

Dominant taxa at all sites were reflective of climax communities that have undergone long-term successional development in resppnse to more stable sedimentary environments.

Surface deposit-feeding oligochaetes and polychaetes continued to be dominant organisms at all sites in 2014. Multidimensional scaling showed distinct separation of communities affected by construction (IN) and initial operation of Unit 3 (JC and BF). Changes in community structure and functional group dominance at subtidal benthic infauna} stations during the period 1980-2014 reflect not only effects related to construction and initial operation of.MPS Unit 3, but other regional and/or local biotic and abiotic factors. Community changes at th<:: reference site (GN) during the period 1980-2014 were attributed solely to these latter factors, and not to operation of MPS.

Winter Flounder Studies Various life history stages of Winter Flounder have been monitored since 1976 to determine what effect, if any, MPS may have on the local Niantic River population, particularly through the entrainment of larvae. Over the past two decades, low Winter Flounder abundance levels have been found throughout LIS by the Connecticut Department of Energy and Environmental Protection (CTDEEP). During the same time period, adult Winter Flounder abundance in the Niantic River has remained low. A total of 15 adult flounder were captured in the 2014 Winter Flounder spawning survey, with no recaptures from past years.

Reflecting the trend of record low abundance, CPUE in 2014 was 0.3 fish per standardized tow, the second lowest value of the time-series (1976-2014).

In 2014, larval abundances in Niantic Bay (Stations EN and NB) and Niantic River (Stations A, B, and C) were lower than 2013 values. All larval stages for the Niantic River stations were some of the lowest values in recent years, while larval abundances in Niantic Bay were just below or close to average for the time-series.

Relative to the Niantic River, larval abundance in Niantic Bay has increased in recent years, suggesting higher production in LIS rather than in estuaries such as the Niantic River. As expected from the low, late-stage larval abundance in 2014, juvenile abundance from the Niantic River beam trawl survey was low.

The number of larvae entrained at.MPS is a measure of potential impact to Winter Flounder.

Annual estimates of entrainment are related to both larval densities in Niantic Bay and.MPS cooling-water volume. The 2014 entrainment estimate of 86.2 million reflected slightly lower than average Niantic Bay larval densities. An entrainment reduction of 55.7% (based on maximum permitted flow) in 2014 can be attributed to the use of the variable frequency drives (VFDs) during the "Interval" (defined in the.MPS NPDES permit as the Executive Summary ii

period "from April 4 to May 14 or the first day after May 14 when the intake water temperature reaches 52

°F, whichever is later, but no later than June 5") and the Unit 2 outage, which lasted from April 5th to May 15th.

Annual entrainment density (abundance index divided by total cooling water volume) has varied without trend since 1976, indicating that larval production and availability in Niantic Bay remained relatively stable despite increased water use during the 1986-95 period of three-unit operation and reduced cooling-water use in 1995-97. Correlations between entrainment estimates and abundance indices of post-entrainment age-0 juveniles were positive. This implies no entrainment effect, as the more larvae that were available for entrainment, the more larvae metamorphosed and settled in Niantic River and Bay. This was also demonstrated by a comparison of annual entrainment and juvenile year-class abundance, which suggested that entrainment estimates were simply a measure of emerging year-class strength. Thus, entrainment is not an important factor in determining juvenile abundance.

Processes that are unrelated to MPS operation and which occur after juvenile Winter Flounder leave shallow nursery waters during the fall of their first year of life seem to be operating to account for fewer adults.

A bottleneck in recruitment may occur during the late juvenile life stage (ages-1 and 2), probably from predation. Environmental effects, including changes to the Niantic River habitat (e.g., widely fluctuating eelgrass abundance), a warming trend in regional seawater temperature, and interactions with other species (e.g., predation), especially during early life history, are also important processes affecting Winter Flounder population dynamics.

Results from Winter Flounder studies through 2014 suggest that MPS operations have had minimal effects on Winter Flounder biomass in the Niantic River.

Declines in stock size have been greatly evident on a regional basis, including Long Island Sound, Rhode Island and all other Southern New England waters.

Entrainment during the larval life stages of Winter Flounder occurs, however there has been large variation in the amount of larval mortality and recruitment in recent years, both occurring independently of MPS operations.

Fish Ecology Studies Results from the Fish Ecology monitoring studies during 2014 indicate that no long-term abundance trends for various life stages of seven selected species could be directly related to MPS operation.

No significant long-term trends in abundance were identified for Anchovy, Cunner and Tautog eggs, American Sand Lance, Anchovy, and Grubby larvae, or juvenile and adult Silversides.

Atlantic Menhaden larvae showed a significantly increasing trend in abundance, as did juveniles taken by seine and trawl. A significant decreasing trend was exhibited for Grubby collected at the Intake, Jordan Cove, and Niantic River trawl stations.

Over the past 39 years, Cunner and Tautog larval abundances have significantly increased.

Juvenile and adult Cunner decreased in Intake and Jordan Cove trawl and lobster pot catches and increased in Niantic River trawls. Trawl catches of juvenile and adult Tautog have significantly increased at the Niantic River station, but decreased at Intake.

The magnitude of entrainment is dependent upon egg and larval densities and condenser cooling water flows during their periods of occurrence.

Reductions in cooling-water flows have been implemented at MPS with the use of VFDs during the peak period of Winter Flounder annual spawning. In addition to the Unit 3 fish return, which was in operation at unit start-up in 1986, impingement impacts were further reduced at MPS with the installation of a fish return at Unit 2 in early 2000.

The implementation of these mitigation measures serve to minimize entrainment and impingement impacts at MPS.

Annual variations in ichthyoplankton entrainment likely reflected differences in spawning and transport of eggs and larvae within LIS.

Other factors, such as extremes in seasonal water temperature, may al.so affect larval growth and development. A number of temporal and spatial changes were identified in the community of fishes and macroinvertebrates collected in the MPS trawl monitoring program.

These changes were unrelated to the operations of MPS, but rather were associated with shifts in the dominance of individual taxa* from changes in habitat, range extensions or contractions related to a warming trend in ambient seawater temperature that has occurred over the past three decades, and changes in fishing rates and fishing regulations.

Executive Summary m