ML12130A266

Annual Environmental and Annual Radiological Environmental Operating Reports - Cover Through Chapter 5

ML12130A266
Person / Time
Site:	South Texas
Issue date:	04/30/2012
From:	Lofton P, Stoicescu L South Texas
To:	Office of Nuclear Reactor Regulation
References
Download: ML12130A266 (41)

Text

Attachment South Texas Project Units 1 and 2 2011 Annual Environmental and Annual Radiological Environmental Operating Reports

Sot Tea Prjc Elcti Geeatig Stto Opraig Reporta

The 2011 Annual Environmental Operating Report for the South Texas Project Electric Generating Station combines in one report the requirements for the Annual Environmental Operating Report (Non-radiological) found in Appendix B to Facility Operating License Nos. NPF-76 and NPF-80 and the requirements for the Annual Radiological Environmental Operating Report found in Part A of the station's Offsite Dose Calculation Manual.

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Graphics and artworkperformed by BarbaraCarnley Photographyperformed by: Steve Antonio, Cheryl Bentley, Karen Bishop, BarbaraCarnley, Kim Danielski,Sherrie Deen, Thomas Dennis, Mary Dykes, Connie Milliff James Handy, FrankJacobus, Jodie Jankauskas, Gwenna Kelton, Nancy Kubecka, Russell Kiesling, Michael LeMay, Kristy Moss, Gary Parkey,Aubrey Passafuma,Mark Scheuerman, Tammy Stevens, STP CorporateCommunications, STP Green Team, Bernadette White, Gordon Williams Cover photo by: Gary Parkey o09 Maps provided by Janice Hopes

Completed in accordance with Technical Specifications for United States Nuclear Regulatory Commission License Nos.

NPF-76 and NPF-80 April 2012 Authored by:

Laura' Stoicescu Staff Health Physicist Health Physics Division and reggy,.tton IrAvis, J.D.

Staff Consultant Environmental Division Technical Review:

/ arrell Sherwood, Ph.D.

Supervisor Health Physics Division Approved by:

Roge A. Aguilera Manager Health Physics Division 2011 Annual Environmental Operating Report SOUTH TEXAS PROJECT ELECTRIC GENERATING STATION

Table of Contents E xecutive Summ ary ................................................................................................... 1-2 Site and Area Description .......................................................................................... 2-2 Non-Radiological Environmental Introduction and Summary .................................. 3-2 Non-Radiological Environmental Operating Report ................................................. 4-2 Environmental Conditions .............................................................................. 4-2 Aquatic and Ecological Monitoring ..................................................... 4-3 Water Quality Management ................................................................. 4-5 Air Quality Management ..................................................................... 4-9 Non-Radioactive Waste Management .................................................. 4-11 Chemical Control and Management .................................................... 4-14 Environmental Protection Plan Status ............................................................ 4-15 Radiological Environmental Introduction and Summary .......................................... 5-2 Radiological Environmental Operating Report ......................................................... 6-2 Program D escription ....................................................................................... 6-2 Analysis of Results and Trends ........................................................... 6-6 L and U se Censu s ............................................................................................ 6-15 Q uality A ssurance ........................................................................................... 6-16 Program D eviations ........................................................................................ 6-18 NEI Groundwater Protection Initiative ........................................................... 6-18 Fukushim a D aiichi .......................................................................................... 6-20 2011 Radiological Environmental Monitoring Program Analysis Summary. 6-30 List of Figures Figure 2-1: Plant Water Systems Diagram ........................................................................ 2-4 Figure 4-1: 2011 Nonradioactive Waste Management .................... 4-13 Figure 4-2: 2011 Nonradioactive Waste Generation ....................................................... 4-13 Figure 4-3: Hazardous Waste Shipped Historical Comparison ..................................... 4-14 i STP Nuclear Operating Company

2011 EnvironmentalReport Figure 6-1: Radiological Environmental Monitoring Program Designated Sample Location Map ....................................... 6-3 Figure 6-2: Radiological Environmental Monitoring Program Onsite Sample Location Map .................................................................................... 6-4 Figure 6-3: Radiological Environmental Monitoring Program Zone L ocation Map .................................................................................................... 6-5 Figure 6-4: Historical Comparison ofAverage Quarterly Beta Activity from Indicator and Control Air Samples ....................................................... 6-6 Figure 6-5: Environmental Dosimeter Comparisons ...................................................... 6-7 Figure 6-6: Historical Comparison of Cobalt-58 and Cobalt-60 in Main Cooling Reservoir Sediment........................................................................... 6-9 Figure 6-7: Calculated Cumulative Curies of Cobalt-60 in the Main C ooling Reservoir ............................................................................................ 6-9 Figure 6-8: Historical Comparison ofTritium Added to and Remaining in the Main Cooling Reservoir ........................................................................... 6-10 Figure 6-9: Historical Comparison ofTritium Activity in Reservoir R elief Wells ........................................................................................... .......... 6-11 Figure 6-10: Historical Comparison ofTritium Activity in Surface Water .................... 6-13 Figure 6-11: Historical Comparison ofTritium Activity in Shallow Aquifer Ground Water .................................................................................................... 6-13 Figure 6-12: Tritium Activity in Shallow Ground Water West of the Main C ooling Reservoir ............................................................................................. 6-14 Figure 6-13: 2011 Radiological Laboratory Quality Assurance Program Perform ance ...................................................................................... 6-16 Figure 6-14 2011 Duplicate & Split Sample Agreement .................................................. 6-17 Figure 6-15: STP Protected Area Ground Water Monitoring Wells ............................... 6-19 List of Tables Table 1: Radiological Environmental Monitoring Program ................... 6-21 Table 2: Sample Media and Location Descriptions ................................ 6-24 Table 3: 2011 Radiological Environmental Monitoring Program A nalysis Summary .................................................................... 6-31 STP Nuclear Operating Company ii

Photo By: JodieJanauskas STP Nuclear Operating Company

Photo Bl. h/m/lI.IS/cIvils Cbppter I

-ErecutiveSummary The South Texas Project continues to operate with no adverse effect on the population or the en-vironment. The exposure for people living in the area remains at less than one millirem per year.

Environmental programs at the site monitor known and predictable relationships between the op-eration of the South Texas Project and the surrounding area. These monitoring programs verify that the operation of the South Texas Project has no impact offsite and is well within state and federal regulations and guidelines. These programs are verified by the State of Texas through collection and analysis of samples and placement of the State's monitoring dosimeters and other onsite and offsite inspections.

This report describes the environmental monitoring programs, radiological and non-radiological, conduct-ed at the South Texas Project during 2011. Included in this report are the Environmental Protection Plan Status, the results of the Radiological Environmental Monitoring Program, and the Land Use Census.

Non-radiological environmental monitoring is performed each year as part of the station's overall Envi-ronmental Protection Plan which is intended to provide for protection of non-radiological environmental values during station operations. Non-radiological monitoring encompasses, as a minimum, water quality, air quality, waste generation and minimization, and local aquatic and terrestrial ecological conditions. In 2011, non-radiological monitoring by the station confirmed that the South Texas Project's efforts to respect and protect local environmental conditions were successful. The South Texas Project continued to be rated by the Texas Commission on Environmental Quality as a high performer in the area of environmental compliance, continued to provide high-quality habitat areas for a variety of flora and fauna, and continued to have no indications of negative non-radiological impacts to local environmental conditions.

The environment, within a 15-mile radius of the South Texas Project, is routinely monitored for radiation and radioactivity. Sampling locations are selected using weather, land use, and water use information.

Two types of sampling locations are used. The first type, control stations, are located in areas that are be-yond the measurable influence of the South Texas Project or any other nuclear facility. The sample results from these stations are used to explain radiation from sources other than the South Texas Project. Indicator stations are the second type of stations. The samples from these stations measure any radiation contributed to the environment that could be caused by the South Texas Project. Indicator stations are located in areas close to the South Texas Project where plant releases are monitored.

Prior to initial operation of the South Texas Project, samples were collected and analyzed to determine the amount of radioactivity present in the area. These results are used as a "pre-operational baseline." Results from the indicator stations are compared to both current control sample results and the pre-operational baseline values to determine if changes in radioactivity levels are attributable to station operations or other causes such as previous nuclear weapons testing programs and natural variations.

Radioactivity levels in the South Texas Project's environment frequently fall below the minimum detection capabilities of state-of-the-art scientific instruments. Samples with radiation levels that cannot be detected are below the Lower Limits of Detection. The United States Nuclear Regulatory Commission requires that equipment used for radiological monitoring must be able to detect specified minimum limits for certain types of samples. This ensures that radiation measurements are sufficiently sensitive to detect small chang-es in the environment. The United States Nuclear Regulatory Commission also has a required reporting level. Licensed nuclear facilities must prepare a special report and increase their sampling if any measured 1-2 STP Nuclear Operating Company

2011 EnvironmentalReport radiation level is equal to or greater than this reporting level. No sample from the South Texas Project has ever reached or exceeded this reporting level.

Measurements made are divided into four categories or pathways based upon how the results may affect the public. Airborne, waterborne, ingestion, and direct radiation are the four pathways that are sampled. Each pathway is described below.

The airborne pathway is sampled in areas around the South Texas Project by measuring radioactivity of iodine and particulate air filters. The only activity other than natural radioactivity measured at the con-tinuous air monitoring stations in 2011 originated from the tragic events that occurred in March of 2011 at the Fukushima Daiichi nuclear power station in Japan. The results of these particular air samples as well as several additional measurements in response to the events at the Fukushima Daiichi nuclear power station are discussed in Chapter 6.

The waterborne pathway includes samples taken from surface water, ground water, and drinking water.

Also included in this pathway are sediment samples taken from the Main Cooling Reservoir and the Colorado River. Tritium was the only man-made isotope consistently detected in water samples and was measured in the shallow aquifer, the Main Cooling Reservoir, ditches, and sloughs consistent with the South Texas Project Main Cooling Reservoir operating design. The levels of tritium found were near or lower than the concentration of the Main Cooling Reservoir. Additional onsite wells have been sampled to map tritium migration. The average tritium level in the Main Cooling Reservoir increased slightly in 2011 compared to years past due to extreme drought conditions limiting the ability to refill the reservoir during the year. Tritium levels remain well below United States Nuclear Regulatory Commission reporting limits and within United States Environmental Protection Agency drinking water standards. Previously detected plant-related isotope, Cobalt-60, was detected in the reservoir sediment this year at the designated sample locations. Several samples had detectable Cesium-137 which is pres-ent in the environment and was detected at pre-operational concentrations. Offsite sediment samples continue to show no radioactivity from the South Texas Project. In summary, the station produces no detectable waterborne effects offsite.

" The ingestion pathway includes broadleaf vegetation, agricultural products, and food products. Natu-rally occurring isotopes were detected at average environmental levels in the samples. The data indi-cated that there were no man-made isotopes detected in these types of samples.

" The direct exposure pathway measures environmental radiation doses using thermoluminescent dosim-eters. These results are consistent with the readings from previous years and continue to show no effect from plant operations.

The South Texas Project continues to operate with no negative effect on the population or the environ-ment. The dose for people living in the area is maintained at less than one millirem per year. Environmental programs at the site monitor known and predictable relationships between the operation of the South Texas Project and the surrounding area. These monitoring programs verify that the operation of the South Texas Project has no impact offsite and is well within state and federal regulations and guidelines. These programs are verified by United States Nuclear Regulatory Commission inspections, STP Nuclear Operating Company sponsored quality assurance audits, and the State of Texas through collection/analysis of samples and State radiation monitoring dosimeters.

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Photo By: Karen Bishop 1-4 STP Nuclear Operating Company

OVA Mrs-LAM Pholo coill loýl

Site and Area Description The South Texas Project is located on 12,220 acres in Matagorda County, Texas, approxi-mately 15 miles southwest of Bay City along the west bank of the Colorado River. The South Texas Project Electric Generating Station is owned by NRG Energy, Inc., Austin Energy, and CPS Energy as tenants in common. Houston Lighting & Power Company was the original project manager of the South Texas Project and was responsible for the engineering, de-sign, licensing, construction, startup, and initial commercial operation of the two-unit facility.

In 1997, the STP Nuclear Operating Company assumed operational control of the South Texas Project and responsibility for implementation of associated environmental programs.

The South Texas Project has two Westing-house pressurized water reactors. The nominal net electrical capacity of each unit is 1,250 megawatts-electric (MWe). Unit 1 received a low-power testing license on August 21, 1987, achieved initial criticality on March 8, 1988, and was declared commercially operational on August 25, 1988. Unit 2 received a low-power testing license on December 16, 1988, achieved initial criticality on March 12, 1989, and was declared commercially operational on June 19, 1989. The combined units currently produce enough electricity to serve more than two mil-lion homes and businesses throughout Texas.

With nearly 1,200 baseline employees, the STP Nuclear Operating Company is the largest employer and source of revenue for Matagorda County.

The South Texas Project initiated activities in 2008 to pursue renewal of the operating licenses for Units 1 and 2 from the United States Nuclear Regulatory Commission. The license renewal application was submitted to the United States Nuclear Regulatory Commission in October of 2010 to request authorization to operate the South Texas Project, Units 1 and 2, for an ad-ditional 20 years beyond the period specified Photo courtesy of: STP CorporateCommunications 2-2 STP Nuclear Operating Company

2011 EnvironmentalReport in the current licenses. The United States Nuclear Regulatory Commission determined that the South Texas Project submittal was sufficient to enable them to undertake a review of the applica-tion. The review process is intended to ensure that the plant's original design and current condi-tions and programs can allow the facility to continue operating safely beyond its original license.

In July of 2011, a review team consisting of staff from the United States Nuclear Regulatory Commission and a contractor from Pacific Northwest National Laboratory participated in a site audit at the South Texas Project related to the environmental review of the South Texas Project, Units 1 and 2, license renewal application. The primary goal of the site visit was to review docu-mentation, gather information to ensure that the environmental requirements of license renewal were met in accordance with Title 10 of the Code of Federal Regulations Part 51 and to interface with officials from local government agencies to obtain related information outlined in the audit plan. The United States Nuclear Regulatory Commission did not identify any significant envi-ronmental issues during its site audit. Most of the audit team's questions were answered during conduct of the audit. Additional information necessary to support the environmental review was formally requested subsequent to the audit as part of the United States Nuclear Regulatory Com-mission's Request for Additional Information process and responded to by STP Nuclear Operat-ing Company.

In September of 2007, a Combined Construction and Operating License Application (COLA) was filed with the United States Nuclear Regulatory Commission to build and operate two addi-tional units, Units 3 and 4, at the South Texas Project. Efforts continue to secure licensing for the two new units. Nuclear energy continues to provide long-term cost stability and promote energy independence. It is our nation's largest source of carbon-free energy. As we work collectively to secure our state's long-term energy future, nuclear energy will continue to play an important role as a safe and reliable supply of clean baseload electricity.

How the South Texas Project Works Fossil-fueled and nuclear-powered steam generating plants operate on the same principle. Fuel is used to produce heat to convert water into high-pressure steam. The steam is directed through a turbine to turn a generator. In a fossil fuel plant, either coal, lignite, oil or natural gas is burned in a boiler to produce the heat. In a nuclear plant, the reactor replaces the boiler and the "fission-ing" or splitting of uranium atoms inside the reactor produces the heat.

The fuel for a nuclear reactor is uranium. It is formed into cylindrical ceramic pellets, each about the size of the end of your little finger. One pellet has the energy potential of about a ton of coal.

Millions of these pellets are stacked in fuel rods that are arranged into assemblies that make up the core of the reactor. The use of uranium allows us to conserve natural gas, oil and coal and to avoid the associated production of greenhouse gases.

The fission process and generation of usable heat begins in a nuclear reactor when control rods in the core are withdrawn. In pressurized water reactors, like those at the South Texas Project, the fuel rods heat water circulating in sealed, stainless steel piping that passes through large heat exchangers called steam generators. The water in the reactor is under pressure to prevent boil-ing. This is why the South Texas Project's Units 1 and 2 reactors are called "pressurized water reactors."

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Site andArea Description This hot, pressurized water heats a separate supply of water in the steam generators to produce steam that is directed through the blades of a turbine generator to produce electricity. The steam is then fed to a condenser where a separate supply of cooling water from the reservoir turns it back into water that is then pumped back to the steam generator for reuse. A diagram of the plant water systems is shown in Figure 2-1.

In addition to its safety systems, the South Texas Project has many built-in physical barriers that would prevent the release of radioactive materials in the unlikely event of an accident. The most visible ones are the 200-foot-tall, domed containment buildings with steel-reinforced concrete walls four feet thick. Inside each of these massive structures, two more concrete walls provide another 11 feet of shielding. The reactor vessel itself has steel walls six inches thick, and the fuel pellets inside it are sheathed in hardened metal tubes.

Nuclear energy has one of the lowest impacts on the environment. It is the most eco-efficient energy source because it produces the most electricity in relation to its minimal environmen-PLANT WATER SYSTEMS PRESSURIZER STEAM SECONDARY LOOP GENERATOR REACTOR CIRCULATING COOUNG IPPUM PM PUMP i ) RESERVOIR (7000 ACRE LAKE)

PRIMARY LOOP CONTAINMENT COOUNG LOOP Figure 2-1 2-4 STP Nuclear Operating Company

2011 EnvironmentalReport Photo courtesy of STP Corporate Communications tal impact. In 2010, the most recent year for which data is available, nuclear generation in the United States prevented 642.09 million metric tons of carbon dioxide, 1.60 million tons of sulfur dioxide, and 0.56 million tons of nitrogen oxide from entering the Earth's atmosphere.' Nuclear power plants generate nearly 70 percent of all clean-air electricity in the United States.2 Ad-ditional information on nuclear energy and the environment can be found on the website main-tained by the Nuclear Energy Institute at http://www.nei.org.

The PlantSite Sixty-five of the entire 12,220 acres at the South Texas Project are occupied by the two current power plants. Plant facilities include a 7,000-acre main cooling reservoir and a 47-acre essen-tial cooling pond. Many smaller bodies of water onsite include wetlands, Kelly Lake, drainage ditches, sloughs, and depressions. Much of the land east of the cooling reservoir is leased for cattle grazing. Approximately 1,700 acres remain in a more natural state as a lowland habitat.

A 110-acre wetland habitat area was established in 1996 on previously unused land located northeast of the power plants. The area surrounding the South Texas Project is characterized by coastal plain with farmland and pasture predominating. Local relief of the area is characterized by flat land, approximately 23 feet above sea level.

'-Nuclear Energy Institute. Emissions Avoided by the U.S. Nuclear Industry (1995- 2010). http://www.nei.org/

resourcesandstats/documentlibrary/protectingtheenvironment/graphicsandcharts/emissionsavoidedbythe usnclearin-dustryyearly/. May 2011.

2 Nuclear Energy Institute Fact Sheet. Nuclear Energy and the Environment. http//www.nei.org/keyissues/protec-tingtheenvironment/factsheets/nuclearenergyandtheenviroment/. June 2011.

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Site and Area Description The Area The economic base for this area primarily is agriculture-related. The chief agricultural products in Matagorda County are livestock, grain sorghum, corn for grain, rice, cotton and hay. In addition to the agriculture industry, there is commercial fishing in the lower Colorado River, East and West Matagorda Bays, Intracoastal Waterway and the Gulf of Mexico. Cur-rently shrimp, oysters, crab, and fin fish such as black drum are the predominant commercial fish in the county.

Although the surrounding area is heavily cultivated, significant amounts of woodlands, thicket, brush, fields, marsh, and open wa-ter exist to support wildlife.

The area lies in the south-ern region of the central Photo courtesy of: STP Corporate Communications flyway and is host to an abundance of migratory birds. The local estuary environments provide the necessary habitat for a variety of fish types to complete their life cycles. The area also affords opportunity for recre-ational hunting and fishing.

The South Texas Project is home to many species of animals. Inhabitants include American alli-gators, ospreys, and several hundred deer. In winter, literally hundreds of thousands of waterfowl, principally migratory geese as well as white pelicans and the common tern, have found that the plant's 7,000-acre cooling reservoir provides a good resting place during their migrations.

The climate of the region is subtropical maritime, with continental influence. It is characterized by short, mild winters and long, hot and humid summers. Rainfall is usually abundant throughout the year with an annual average of approximately forty-two inches. The prevailing wind direc-tion is from the south-southeast, shifting to north-northeast for short intervals during the winter months.

2-6 STP Nuclear Operating Company

Non-RadiologicalEnvironmentalIntroductionand Summary Photo By: FrankJacobus Non-radiological environmental conditions and performance at the South Texas Project during 2011 remained satisfactory and demonstrated that the South Texas Project continued to operate in an environmentally responsible manner during the year. The South Texas Project achieved and maintained high standards of environmental performance and compliance throughout 2011.

The South Texas Project is committed to the production of electricity in a safe, reliable, and economical manner using nuclear energy. The station's programs, policies and business plan objectives also incorporate a commitment to environmental protection and sound environmental management. The station's commitment to sound environmental management is illustrated by the following successes in 2011.

Continued classification as a high performer by the Texas Commission on Envi-ronmental Quality based on the station's above-average environmental compliance record in all areas considered, including water quality, waste management, and air quality compliance; 3-2 STP Nuclear Operating Company

2011 EnvironmentalReport Completion of three outside regulatory agency inspections/audits with no regulatory noncompliances identified;

• Zero reportable spills or leaks; Completion of the station's fourteenth year of operation with a 100% wastewater discharge compliance rate; and, Sponsorship of and participation in multiple onsite and community-wide green initia-tives and programs.

Everyone has a responsibility to protect the environment. Commitment to environmental responsibility is an integral component of the South Texas Project operating policy and core values. This responsibility reaches further than mere compliance with laws and regulations to encompass the integration of sound environmental practices into our daily operational and business decisions. The people at the South Texas Project understand the need to balance economic, operational and environmental issues for the benefit of the station and the public.

We recognize our responsibility to hold ourselves to the highest principles of environmental stewardship for station activities.

Photo By: Thomas Dennis STP Nuclear Operating Company 3-3

Photo By: Ciwenna Kelton 3-4 STP Nuclear Operating Company

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Non-RadiologicalEnvironmentalOperatingReport ENVIRONMENTAL CONDITIONS This section of the report describes the South Texas Project's non-radiological environmental program performance and environmental conditions from January 1 through December 31, 2011. The STP Nuclear Operating Company closely monitors envi-ronmental conditions and performance at the South Texas Project. NRG Energy, Inc. provides support and technical assistance to the South Texas Project.

In addition to the site environmental audit conducted by the United States Nuclear Regulatory Commis-sion discussed in Chapter 2, the Texas Commission on Environmental Quality conducted an air quality permit compliance inspection in 2011 with no find-ings or violations issued. The Texas Commission on Environmental Quality also conducted a dam safety inspection of the station's Main Cooling Reservoir and Essential Cooling Pond finding that each was in Photo By: BarbaraCarnley overall good condition.

The Texas Commission on Environmental Quality classified the South Texas Project as a high performer in 2011 based on the station's above-average environmental compliance record. Fa-cilities, such as the South Texas Project, are classified by the state as a high performer, average performer, or poor performer based on that facility's compliance history. The state's classifica-tion of the South Texas Project as a high performer was based on the station's environmental performance over the last five year period. In addition, the STP Nuclear Operating Company continued to participate in the Texas Commission on Environmental Quality CLEAN TEXAS program as a bronze-level member in 2011.

- The South Texas Project, along with other local industries and organizations co-sponsored and participated in the annual Matagorda County Household Hazardous Waste Collection Day in the fall of 2011. The STP Nuclear Operat-ing Company formed an employee-led group, the STP Green Team, in 2008 to encourage and promote sustainable "green" initiatives and policies at the station and among employees. In 2011, the STP Green Team continued to pro-mote a "Turn Off Lights" campaign for energy conservation, a program encouraging carpool-ing among employees, recycling of plastics Photo By: Mary Dykes and aluminum, and employee participation in 4-2 STP Nuclear Operating Company

2011 EnvironmentalReport community area projects such as the county's Household Hazardous Waste Collection Day. The STP Green Team also sponsored sta-tion participation in the Matagorda County Beach Cleanup, an E-Waste Collection Day for employ-

-STP Nuclear Operating "Company -Underground Services-Markham ees and a "ReUse-a-Shoe" cam- I  : LyondellBasell -OXEA Celanese -Chevron-Phillips

. Zachry (Phillips &Lyondell) °Mundy . Whamco . Matagorda County

. Clean Harbors paign. In addition, the STP Green The City of Bay City. Conoco Philips. Baycel FCU°Wharton County Junior College Team teamed up with the Keep Bay City Beautiful committee to spearhead a clothing drive along with other station organizations Thi.i -o-iONT RN

• AHMI /UJlNbS5WA lbI Used Motor Oil EXPLOSIVES SAntifreeze to recycle gently used clothes to

• Brake/Transmission Fluid RADIOACTIVE DIOXINS MATERIAL be donated to the Bay City Crisis

• OldDiesel/ Gasoline TV'S

• Pesticides/ Herbicides / Insecticides MAGAZINES ORNEWSPAPERS Center. The station also contin- *PoolChemicals COMPRESSED GASCYLINDERS ued to support various bird counts

• Paints /Thinners (WillRecycleto the Public)

HouseholdCleaners and surveys in 2011 sponsored

• DrainOpeners

• StainRemovers by federal and state agencies and Furniture Polish/Wood Preservatives sdeasgainnD* e a ouretoy bsNr

, Cookng Oil sRnslvedcmens thatame nl1ngerneded.

volunteer organizations such as gEamples:

Batteries(Auto,Rechargeable, Alkaline) BankStatements the annual National Audubon OldAppliances(with/ without Freon)

• InsuranceForms

,CreditCardStatements Tires(8)NOSemiorTractorTires Income TaxRecords Society Christmas Bird Count, the Productslabeled"Warning / Caution

, MedicalRecords I Poison* Investment information Great Texas Birding Classic, and e-Waste:Computers,Printers,CellPhones Limit f6boxes(1xt2.5xl0)perhousehold.

personal paperproductssnly!

the United States Fish and Wild-life Service Colonial Waterbird Survey.

AQUATIC AND ECOLOGICAL MONITORING The location of the South Texas Project falls within the Texas Land Resource Area designation as coastal prairie and can be divided into two broad ecological areas based on topography, soils, and vegetation. The bottomland lowland habitat is a swampy, marshy area that provides an impor-tant habitat for birds and other wildlife and occupies approximately 1,700 acres of the site near the Colorado River. A spoil impoundment constructed in 1972 by the United States Army Corps of Engineers is included in this area. In addition, an award-winning 110-acre wetland habitat area that attracts a variety of bird groups and other wildlife was established in 1996 on previ-ously unused land located northeast of the power plants; however, ongoing drought conditions precluded the seasonal flooding of the wetlands in 2011. The remaining area of the site offers diverse habitats for mammals and several types of birds. The South Texas Project environmental staff regularly monitor the site's environs for changing conditions. Ecological conditions onsite in 2011 remained generally unchanged and satisfactory.

The South Texas Project is located on the state-sponsored Great Texas Coastal Birding Trail that spans the entire Texas Gulf Coast from Brownsville to the Louisiana border. Matagorda County, which includes the South Texas Project, consistently ranks at or near the top of the National STP Nuclear Operating Company 4-3

Non-RadiologicalEnvironmental OperatingReport Audubon Society's annual Christmas Bird Count for the number of species identified. Several bird species listed on the state and federal threatened or endangered species lists have been ob-served visiting the wetland habitat and elsewhere onsite. These include the bald eagle, peregrine falcon, wood stork, white-faced ibis, brown pelican and white-tailed hawk. Additional migratory and resident bird species such as a variety of ducks, geese, turkey and pelicans (both brown and white) have been observed during informal surveys of the site's diverse natural and man-made habitats. The summer of 2007 was the first year on record that brown pelicans were observed on site. Intensive bird nesting continues throughout the lowland habitat, particularly in a heron rookery around the perimeter of Kelly Lake. U. S. Fish and Wildlife Service biologists estimate that approximately one-third of Texas' breeding adult Gull-billed Tern population, considered to be in decline, nest on the internal dikes of the Main Cooling Reservoir at the South Texas Proj-ect. The South Texas Project continues to provide vital habitat for more than an estimated 125 different species of wintering and resident birds.

The South Texas Project continues to monitor important wildlife species to detect population changes. Informal observations by station and NRG Energy, Inc. personnel continue to indicate that the site provides high-quality habitat in which a wide range of animals live. The site contin-ues to attract extensive wildlife populations, offering a refuge for resident species as well as sea-sonal migrants. The lowland habitat located between the Colorado River and the east bank of the Main Cooling Reservoir offers a significant source of water year-round. These natural resource areas, in concert with numerous additional wetland and grassland areas, offer the key ingredients necessary to sustain the extensive wildlife population at the South Texas Project.

Photo By: Gordon Williams 4-4 STP Nuclear Operating Company

2011 EnvironmentalReport WATER QUALITY MANAGEMENT Water is an essential component in electricity production, and all electric utilities must comply with extensive federal, state and local water regulations. These regulations govern virtually ev-ery aspect of business operations at the South Texas Project. Water usage, wastewater treatment onsite and certain maintenance and repair activities are regulated under the Safe Drinking Water Act, the Federal Clean Water Act, and the Texas Water Quality Act. Collectively, these acts pro-vide for the safeguarding of public drinking water supplies and maintaining the integrity of state and federal waters. Regulating agencies that administer these requirements include the United States Army Corps of Engineers, the United States Environmental Protection Agency, the Texas Commission on Environmental Quality, the Texas General Land Office and the Lower Colorado River Authority.

The South Texas Project uses both surface water and groundwater for station purposes. Ground-water is pumped from deep aquifer wells to provide onsite drinking water for station personnel, to replenish the Essential Cooling Pond, and for other industrial purposes onsite. Consistent with the station's environmental principles encouraging efficient water usage and conservation, groundwater usage is carefully managed to conserve this important resource. Water from the Main Cooling Reservoir and the Essential Cooling Pond is used as cooling water for plant activi-ties. Water from the Colorado River replenishes the Main Cooling Reservoir via intermittent pumping periods. Surface water diverted to the Main Cooling Reservoir from the Colorado River accounted for almost 67 percent of the water used at the South Texas Project in 2011. Informa-tion regarding water use in Texas can be found on the website maintained by the Texas Water Development Board at http://www.twdb.state.tx.us/.

Most of the water used by the South Texas Project is needed to condense steam and provide cooling for plant generating systems. The majority of this water is drawn from and returned to the station's Main Cooling Reservoir. The Main Cooling Reservoir is a 7,000-acre, above grade, off-channel reservoir capable of impounding 202,600 acre-feet of water at its maximum level.

Reservoir makeup water is withdrawn intermittently from the adjacent Colorado River. In ad-dition, the Essential Cooling Pond, a 47-acre, below grade, off-channel reservoir that supplies water to cool crucial plant components, is capable of impounding 388 acre-feet of water. Vari-ous water rights permits, contractual agreements, and compliance documents authorize the South Texas Project to maintain these reservoirs, impound water diverted from the Colorado River, and to circulate, divert, and use water from the reservoirs for industrial purposes to operate the plant. These permits also limit the rate of diversion from the Colorado River. Prolonged and widespread drought conditions in 2011 further limited the amount of water available for diver-sion from the river. The South Texas Project diverted 2,267 acre-feet in 2011 from the Colorado River for Main Cooling Reservoir fill operations while preserving adequate freshwater flow con-ditions for downstream bay and estuarine ecosystems. Approximately 33 percent, or 1,122 acre-feet, of the water used by the station was withdrawn from onsite groundwater sources in 2011.

Existing federal and state water quality standards are implemented and enforced through the Texas Pollutant Discharge Elimination System (TPDES) permit program to restore and maintain the state's waters. Under this permit'program, the South Texas Project monitors, records, and STP Nuclear Operating Company 4-5

Non-RadiologicalEnvironmental OperatingReport reports the types and quantities of pollutants from waste-water discharges to ensure that we meet or exceed the stringent levels set in the permit. A monthly monitoring report is submitted to the Texas Commission on Environ-mental Quality for wastewater discharges. In 2009, the South Texas Project applied for a renewal of this waste-water discharge permit and continued to work with the Texas Commission on Environmental Quality through-out 2011 on the renewal to address comments from the United States Environmental Protection Agency. The United States Environmental Protection Agency accepted the proffered comment resolutions and the final permit is anticipated to be issued by the state in the spring of 2012. Reports identifying ground and surface water use are submitted annually to the Texas Water Development Board. Reports of diversion and consumptive use are submitted to the Texas Commission on Environmental Quality. An annual groundwater use report is also sub-mitted to the Coastal Plains Groundwater Conservation Photo By: Cheryl Bentley District.

Wastewater generated at the South Texas Project is processed and discharged to the onsite Main Cooling Reservoir to be re-used by the station as cooling water for plant systems. No water was discharged from the reservoir in 2011. The station continued its outstanding wastewater dis-charge compliance performance record in 2011. Station conditions did not require site aquatic monitoring studies be conducted in 2011, nor were any additional studies required by the United States Environmental Protection Agency or the State of Texas either by way of station discharge permits or otherwise. Wastewater discharges met state and federal water quality standards dem-onstrating a 100 percent compliance record for the year while conserving and maximizing effi-cient water usage at the station.

In addition to the wastewater discharge permit program, the Federal Clean Water Act, as amend-ed, requires permits for storm water discharges associated with industrial activity. The South Texas Project Storm Water Pollution Prevention Plan ensures that potential pollution sources at the site are evaluated and that appropriate measures are selected and implemented to prevent or control the discharge of pollutants in storm water runoff. This plan is a working document that is revised whenever there is a change in design, construction, operation, or maintenance that has a significant effect on the potential for the discharge of pollutants from the station. The United States Environmental Protection Agency modified the multi-sector general storm water permit and Texas renewed the general permit in August 2011. Subsequently in 2011, the station filed a Notice of Intent for coverage under the modified permit and the Storm Water Pollution Preven-tion Plan was updated accordingly.

Following a severe drought in 1996, the Texas Legislature recognized the need to address a wide range of state water resource management issues. In 1997, the Texas Senate drafted legislation 4-6 STP Nuclear Operating Company

2011 Environmental Report known as Senate Bill 1 to address these issues and to develop a comprehensive state water policy. Towards this end, this legislation required that the Texas Water Development Board create a statewide water plan that emphasizes regional planning. Sixteen planning regions were created, each tasked to prepare a regional plan for the orderly development, management and conservation of water resources. The South Texas Project was chosen to represent the electric generating utility interest for the water-planning region, Region K, encompassing the lower Colorado River Basin. A state water plan is prepared by the Texas Water Development Board based on the regional water plans that are developed every five years by the regional water planning groups. Texas has now completed the third cycle (2006-2010) of the regional water planning process. In October 2010, the Texas Water Development Board approved the final version of the 2011 Region K Water Plan for subsequent integration into the 2012 State Water Plan. The fourth cycle of regional and state water planning commenced in 2011 and will extend through 2016. For the fourth cycle of regional planning, the 2010 United States Census data will be used as the basis for revision of the regional water plans including the associated population and water demand projections, water supply analyses and water management strategies for a water planning horizon out to the year 2070. The South Texas Project continues to actively participate in the Lower Colorado Regional Water Planning Group to identify strategies to meet future water supply demand projections for the region and update the existing plan accordingly.

Additional information regarding regional water planning in Texas can be found on the website maintained by the Texas Water Development Board at http://www.twdb.state.tx.us/.

Senate Bill 1 also required groundwater conservation districts to develop groundwater manage-ment plans with estimates on the availability of groundwater in the district, details of how the district would manage groundwater, and management goals for the district. The water planning and management provisions were further clarified in 2001 with the enactment of Senate Bill 2.

Accordingly, the Coastal Plains Groundwater Conservation District encompassing Matagorda Photo Lfy: Connte Malitij STP Nuclear Operating Company 4-7

Non-RadiologicalEnvironmentalOperatingReport County was confirmed by local election in late 2001. The purpose of the District is to "...man-age and protect the groundwater resources of the District." The South Texas Project actively par-ticipated in development of the Coastal Plains Groundwater Conservation district rules prior to their initial adoption and continues to participate in subsequent amendment activities. In 2005, the South Texas Project registered the station's onsite groundwater wells with the District and renewed the operating permit with the District in 2008 and again in 2011. The station continues to monitor onsite groundwater usage according to the requirements of the District's rules. Addi-tional information regarding the Coastal Plains Groundwater Conservation District can be found on their website at http://www.coastalplainsgcd.com/.

In 2007, in further recognition of the importance of water conservation to meet future demands in the state, Senate Bill 3 passed by the Texas Legislature created a stakeholder-driven process for the development of environmental flows. Environmental flows are the amount of water necessary for a river, estuary or other freshwater system to maintain its health and productivity. The law establishes a process to develop environmental flow regime recommendations for each major river basin in Texas. The process tasks a team of stakeholders for each area of the state working with a science team to develop a set of recommendations to submit to the Texas Commission on Environmental Quality. The Texas Commission on Environmental Quality will then consider these recommendations, along with public input, and adopt formal environmental flow standards that must be maintained. The environmental flow standards will set flow levels at various points in rivers and streams to protect water in the rivers and estuaries along the coast. The South Texas Project has participated as an industry representative in the stakeholder committee that includes the Colorado River and Matagorda Photo By: Tammy Stevens 4-8 STP Nuclear Operating Company

2011 Environmental Report Bay since its inception in 2009. The committee submitted its recommendations report to the Texas Commission on Environmental Quality in August of 2011. Rule making by the Texas Commission on Environmental Quality for the Colorado River basin is expected to be completed by the summer of 2012. The existing South Texas Project surface water diversion right is not impacted by this legislation. Additional information regarding environmental flows can be found at http://www.tceq.texas.gov/permitting/water-supply/water-rights/eflows/.

In January 2010, the Texas Commission on Environmental Quality approved a revised Lower Colorado River Authority Water Management Plan. The Water Management Plan determines how water is allocated from the Highland Lakes (specifically lakes Travis and Buchanan) to meet the needs of water users, including the South Texas Project, during water supply shortages.

As part of the of January 2010 approval of the revised Water Management Plan, the Texas Commission on Environmental Quality directed the Lower Colorado River Authority to file an application to revise the Water Management Plan no later than July of 2013. To assist with this update, the Lower Colorado River Authority assembled an advisory committee to represent the diverse interests that rely on the Highlands Lakes water supply. The advisory committee included representatives from cities, industry, lake area business and residents, the environment and agriculture. The advisory committee started in July 2010 and completed its recommendations in late 2011. The South Texas Project represented industrial firm water customers on the advisory committee. Recommendations by the advisory committee to be incorporated into a revised Water Management Plan include, among other things, use of two trigger points during the year (January 1 and June 1) to determine how much stored water from the lakes would be available for agriculture instead of one trigger point on January 1. The Lower Colorado River Authority Board of Directors approved the revised plan on February 22, 2012. It will now be sent to the Texas Commission on Environmental Quality for final approval.

Additional information on the Water Management Plan can be found at http://www.lcra.org.

In 1999, the South Texas Project developed, submitted and implemented an initial station Water Conservation Plan in accordance with state water use regulations. The purpose of the station's Water Conservation Plan is to identify and establish principles, practices, and standards to effec-tively conserve and efficiently use available water supplies and provide historical and projected average industrial water demand. Annual implementation reports are submitted to the Texas Water Development Board. The South Texas Project personnel understand that the water resourc-es of the state are a critical natural resource requiring careful management and conservation to preserve water quality and availability. Accordingly, the station continues to explore and support efforts focusing on the efficient use of water resources and reduction of water waste.

AIR QUALITY MANAGEMENT Air emission sources at the South Texas Project fall under the scope of air pollution regulations promulgated under the Texas Clean Air Act and the Federal Clean Air Act and the numerous associated amendments. The purpose of these regulations is to protect air resources from pollu-tion by controlling or abating air pollution and emissions. The South Texas Project uses small amounts of fossil fuel for backup and emergency equipment. Regulated emission sources at the South Texas Project include a fossil-fuel boiler, diesel-powered emergency generators and fire STP Nuclear Operating Company 4-9

Non-RadiologicalEnvironmental OperatingReport pumps, fire-fighting training, and other minor maintenance equipment and activities. The station submits a report of air emissions annually to the Texas Commission on Environmental Quality.

The South Texas Project has one fossil fuel-fired auxiliary steam boiler available to furnish steam for plant use when steam is not available from the nuclear steam supply system. In addition to the auxiliary steam boiler, a number of fossil-fueled diesel generators are located onsite. These diesels are designed to provide emergency power to various plant systems or buildings in the event of a loss of power. This equipment is not normally needed for daily operations and the station does not use it to produce electricity for distribution. Routine maintenance runs are con-ducted to ensure availability if needed and for equipment maintenance.

In 1990, amendments to the Federal Clean Air Act mandated a permitting program to clearly define applicable air quality requirements for affected facilities such as the South Texas Proj-ect. This program is commonly known as the Title V Federal Operating Permit Program and is administered by the state. The station's Federal Operating Permit grants authority to operate identified emission sources at the station in accordance with applicable permit and regulatory requirements. The South Texas Project applied for renewal of the Federal Operating Permit for the station in 2010 and received the renewed permit in January 2011.

Unlike conventional electrical generating stations, nuclear power plants do not burn fossil fuel for production of electricity. Therefore, the South Texas Project produces virtually no greenhouse gases or other air pollutants that are the typical by-products of industrial production processes.

The use of emissions-free nuclear power is a significant contributor to the preservation of our community's clean air resources.

Photo By: Gwenna Kelton 4-10 STP Nuclear Operating Company

2011 EnvironmentalReport NON-RADIOACTIVE WASTE MANAGEMENT Solid waste management procedures for hazardous and non-hazardous wastes generated at the South Texas Project ensure that wastes are properly dispositioned in accordance with applicable federal, state, and local environmental and health regulations. By regulatory definition, solid waste includes solid, semi-solid, liquid, and gaseous waste material. The Texas Commission on Environmental Quality, which administers the Texas Solid Waste Disposal Act and also the federal Resource Conservation and Recovery Act program, is the primary agency regulating non-radioactive wastes generated at the South Texas Project. The Texas Commission on Environ-mental Quality regulates the collection, handling, storage, and disposal of solid wastes, including hazardous wastes. The transportation of waste materials is regulated by the United States De-partment of Transportation.

The South Texas Project is classified as a small quantity generator of industrial solid wastes.

Texas Commission on Environmental Quality regulations require that industrial solid wastes generated at the South Texas Project be identified to the Commission. These are listed in the Texas Commission on Environmental Quality Notice of Registration for the South Texas Project.

The registration is revised whenever there is a change in waste management practices at the site.

Hazardous waste and Class I non-hazardous waste handling and disposal activities are summa-rized and documented in a waste summary report for the South Texas Project that is submitted annually to the Texas Commission on Environmental Quality.

Hazardous waste accumulation at the South Texas Project in 2011 was limited to a maximum holding period of 180 days. The Resource Conservation and Recovery Act and Texas Solid Waste Disposal Act also requires the use of proper storage and shipping containers, labels, manifests, reports, personnel training, a spill control plan, and an accident contingency plan.

Plant personnel routinely inspect areas throughout the site to ensure wastes are not stored or ac-cumulated inappropriately.

Station policies and regulations encourage the recycling, recovery, or re-use of waste when possible to reduce the amount of waste generated or disposed of in landfills.

Approximately 56 percent, or more than half, of the industrial non-radioactive waste generated in 2011 at the South Texas Project was recycled or processed for re-use. (Reference Figure 4-1) Used oil, diesel fuels, electro-hydraulic fluid and used oil filters are sent to a recycling vendor for re-processing. Empty polyethylene drums are returned, when possible, to the original Photo By: James Handy STP Nuclear Operating Company 4-11

Non-RadiologicalEnvironmental OperatingReport manufacturer for re-use. Non-hazardous blast grit and construction debris were also shipped for recycle in 2011. A site paper recycling program results in the collection of several tons of paper each year. Aluminum and plastics were also collected from employees at the station for recycling. In 2011, the station collected more than 13 tons of combined paper, aluminum and plastic for recycling. In addition, approximately 83 tons of scrap metal were also removed from the station for recycle in 2011. Recycling efforts in 2011 also included 662 square yards of carpet and almost 1 ton of printer cartridges returned for recycling. The station continues to explore new areas where recycling may be expanded or initiated.

Non-radioactive solid waste that cannot be shipped for recycling is shipped for disposal. Mu-nicipal-type trash is transported to an offsite landfill. Successful waste minimization and source reduction efforts by employees have allowed the South Texas Project to remain classified as a small-quantity generator since 2004. Hazardous waste accounts for only a small portion of the waste generated at the South Texas Project; however, minimization and reduction of hazardous waste generation where feasible remains an important goal at the station. (Reference Figures 4-2 and 4-3)

Photo By: Gwenna Kelton 4-12 STP Nuclear Operating Company

2011 Environmental Report 2011 Nonradioactive Waste Management South Texas Project Recycle 56%

Biological Treatment-11%

Incineration & Landfill Biological treatment is the process of Fuel Blending 30% removing contaminants by using 3% bacteriological processes.

Figure 4-1 2011 Nonradioactive Waste Generation South Texas Project Non-Hazardous Waste 99.3%

Universal wastes are items that are generated Hazardous. Universal Waste by large numbers of businesses in relatively Hazardous small quantities such as paint, batteries, W aste Us0d5%

mercury thermostats, obsolete agricultural Used Batteries pesticides and fluorescent/high intensity 0.2% 0.0%

discharge lamps.

Figure 4-2 STP Nuclear Operating Company 4-13

Non-RadiologicalEnvironmentalOperatingReport Hazardous Waste Shipped Historical Comparison South Texas Project 4-3.

02-0 2006 2007 2008 2009 2010 2011 Figure 4-3 CHEMICAL CONTROL AND MANAGEMENT The station's Integrated Spill Contingency Plan for the South Texas Project Electric Generat-ing Station, updated and re-certified in 2009, consolidates multiple federal and state require-ments into one plan. The plan is implemented through standard site operating procedures and guidelines. The South Texas Project uses standard operating procedures, policies, and programs to minimize the generation of waste materials, control chemical usage and prevent spills. The South Texas Project also evaluates chemicals and products proposed for use which could come in contact with plant components. Site procedures address the evaluation, storage, use, spill con-trol, and disposal requirements of chemicals. These guidelines assist in reducing waste genera-tion, ensure proper packaging for disposal and mitigate the consequences of inadvertent spillage.

The South Texas Project emphasizes awareness training for spill prevention and maintains station readiness to respond should a spill occur. Spill response team members receive annual refresher training in hazardous material incident response. No reportable, significant or consequential spills occurred in 2011.

4-14 STP Nuclear Operating Company

2011 EnvironmentalReport ENVIRONMENTAL PROTECTION PLAN STATUS The South Texas Project's Environmental Protection Plan was issued in March of 1989 to pro-vide for the protection of non-radiological environmental values during operation of the South Texas Project. This report reviews Environmental Protection Plan non-compliances identified by the plant in 2011 and the associated corrective actions taken to prevent their recurrence. Poten-tial nonconformities are promptly addressed, as identified, to maintain operations in an environ-mentally acceptable manner. The station uses its Corrective Action Program to document these conditions and track corrective actions to completion. Internal assessments, reviews and inspec-tions are also used to document plant compliance.

This report also reviews non-routine reports submitted by plant personnel and any activities that involved a potentially significant unreviewed environmental question. A proposed change, test or experiment is considered to present an unreviewed environmental question if it concerns:

1) A matter that may result in a significant increase in any adverse environmental impact previously evaluated in the Final Environmental Statement related to the Operation of South Texas Project, Units 1 and 2 (Docket Nos. 50-498 and 50-499), environmental im-pact appraisals, or in any decisions of the Atomic Safety and Licensing Board; or,

2) A significant change in effluents or power level; or,

3) A matter not previously reviewed and evaluated in the documents specified in (1) above, that may have a significant adverse environmental impact.

No unreviewed environmental questions were identified in 2011.

Events that require reports to federal, state or local agencies other than the United States Nuclear Regulatory Commission are reported in accordance with the applicable reporting requirements. The United States Nuclear Regulatory Commission is provided with a copy of any such report at the time it is submitted to the cognizant agency. If a non-routine event occurs and a report is not required by another agency, then a 30-day report to the United States Nuclear Regulatory Commission is required by the Environmental Protection Plan. No such 30-day or other non-routine report Photo courtesy of:STP Green Team of this type was required in 2011.

STP Nuclear Operating Company 4-15

Photo By: Gary Parkey 4-16 STP Nuclear Operating Company

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RadiologicalEnvironmentalIntroductionand Summary The Radiological Environmental Monitoring Program is designed to evaluate the radiological impact of the South Texas Project on the environment by collecting and analyzing samples for low levels of radioactivity.

Measurements of samples from the different pathways indicate that there is no effect offsite from Photo By: Tammy Stevens the operation of the South Texas Project.

The only activity other than natural radioactivity measured at the continuous air monitoring stations in 2011 originated from the Fukushima Daiichi nuclear power station in Japan. Measurements of direct radiation onsite and offsite indicate no dose limits were exceeded. Samples of fish and meat collected and analyzed show no plant-related isotopes were present. Water samples from the onsite drinking water supply from the deep aquifer and offsite sampling stations on the Colorado River show only natural background radioactivity.

Tritium is a radioactive isotope of hydrogen that is produced in the reactor and cannot be removed from effluents released to the Main Cooling Reservoir because it is a part of the water molecule. Due Photo By: Aubrey Passafuma to the design of the Main 5-2 STP Nuclear Operating Company

2011 EnvironmentalReport Cooling Reservoir, the presence of tritium in various sloughs and ditches onsite and the shallow aquifer was expected. Tritium has been detected in these types of samples and the concentrations remain below the United States Environmental Protection Agency drinking water limits.

In 2005, several nuclear plants discovered tritium in groundwater on site at levels exceeding the United States Environmental Protection Agency drinking water limits, mainly near underground process or effluent pipes. To determine if this were the case at the South Texas Project, test wells near underground process and effluent pipes were sampled and analyzed for tritium. Although some results were positive, all results were below the United States Environmental Protection Agency drinking water limits.

A sampling program was developed to monitor the tritium in the immediate area around the nuclear plants for long term trending. Wells are sampled semi-annually, annually, and once every five years, depending on location and the amount of tritium present. The tritium concentration remained below the United States Environmental Protection Agency drinking water limits in 2011 and within the design basis of the South Texas Project.

Analysis of the data collected from the implementation of the Radiological Environmental Monitoring Program indicates that the operation of the South Texas Project has no offsite radiological impact.

Photo By: Gary Parkey STP Nuclear Operating Company 5-3

Photo By: Gary Parkey 5-4 STP Nuclear Operating Company