ML071230071

From kanterella
Jump to navigation Jump to search
2006 Annual Radiological Environmental Operating Report for Period January Through December 2006
ML071230071
Person / Time
Site: Millstone  Dominion icon.png
Issue date: 04/23/2007
From: Price J
Dominion, Dominion Nuclear Connecticut
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
07-0245
Download: ML071230071 (137)


Text

Dominion Nuclear Connecticut, Inc.

Millstone Power Station Dominion Rope Ferry Road Waterford, CT 06385 APR 2 3 2001 U.S. Nuclear Regulatory Commission Serial No. 07-0245 Attention: Document Control Desk MPS Lic/GJC RO Washington, DC 20555 Docket Nos. 50-245 50-336 50-423 License Nos. DPR-21 DPR-65 NPF-49 DOMINION NUCLEAR CONNECTICUT, INC.

MILLSTONE POWER STATION UNITS 1, 2, AND 3 2006 ANNUAL RADIOLOGICAL ENVIRONMENTAL OPERATING REPORT This letter transmits the Annual Radiological Environmental Operating Report for the Millstone Power Station, for the period January 2006 through December 2006. This satisfies the provisions of Section 5.7.2 of Millstone Power Station Unit 1 Permanently Defueled Technical Specifications (PDTS), and Sections 6.9.1.6a and 6.9.1.3 of the Millstone Power Station Units 2 and 3 Technical Specifications, respectively.

If you have any questions or require additional information, please contact Mr. David W.

Dodson at (860) 447-1791, extension 2346.

Very truly yours, J.

Si lice President - Millstone

=Lý-5

Serial No. 07-0245 2006 Annual Radiological Environmental Operating Report Page 2 of 3 Attachments: 1 Commitments made in this letter: None.

cc: U.S. Nuclear Regulatory Commission Region I 475 Allendale Road King of Prussia, PA 19406-1415 Mr. J. A. Golla Project Manager Millstone Unit 1 U.S. Nuclear Regulatory Commission Mail Stop 012H2 One White Flint North 11555 Rockville Pike Rockville, MD 20852-2738 Mr. R. J. Prince NRC Inspector U.S. Nuclear Regulatory Commission Region I 475 Allendale Road King of Prussia, PA 19406-1415 Mr. V. Nerses Senior Project Manager U.S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike Mail Stop 8C2 Rockville, MD 20852-2738 Mr. S. M. Schneider NRC Senior Resident Inspector Millstone Power Station

Serial No. 07-0245 2006 Annual Radiological Environmental Operating Report Page 3 of 3 (2copies)

Director Bureau of Air Management Monitoring & Radiation Division Department of Environmental Protection 79 Elm Street Hartford, CT 06106-5127

Serial No. 07-0245 Docket Nos. 50-245 50-336 50-423 License Nos. DPR-21 DPR-65 NPF-49 ATTACHMENT 1 2006 ANNUAL RADIOLOGICAL ENVIRONMENTAL OPERATING REPORT MILLSTONE POWER STATION UNITS 1, 2, AND 3 DOMINION NUCLEAR CONNECTICUT, INC. (DNC)

Millstone Power Station 2006 Radiological Environmental Operating Report January 1, 2006 - December 31, 2006

__ ~

Dominion Nuclear Connecticut, Inc.

Unit License Docket 1 DPR-21 50-245 2 DPR-65 50-336 3 NPF-49 50-423 FDominion-

ANNUAL RADIOLOGICAL ENVIRONMENTAL OPERATING REPORT MILLSTONE POWER STATION RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM 2006 MILLSTONE UNIT 1, DOCKET NO. 50-245 MILLSTONE UNIT 2, DOCKET NO. 50-336 MILLSTONE UNIT 3, DOCKET NO. 50-423 By the Dominion Nuclear Connecticut, Inc.

Waterford, Connecticut

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 TABLE OF CONTENTS EXECUTIVE

SUMMARY

1. INTRODUCTION ....................................................................................... 1-1 1.1 Overview .......................................................................................... 1-1 1.2 Radiation and Radioactivity ............................................................. 1-1 1.3 Sources of Radiation ....................................................................... 1-2 1.4 Nuclear Reactor Operations ............................................................ 1-3 1.5 Radioactive Effluent Control ............................................................ 1-8 1.6 Radiological Impact on Hum ans .................................................... 1-11
2. PROGRAM DESCRIPTION .......................................................................... 2-1 2.1 Sam pling Schedule and Locations ................................................... 2-1 2.2 Sam ples Collected During Report Period ........................................ 2-7
3. RADIOCHEMICAL RESULTS ....................................................................... 3-1 3.1 Sum m ary Table ............................................................................... 3-1 3.2 Data Tables ................................................................................... 3-19
4. DISCUSSION OF RESULTS ........................................................................ 4-1 4.1 Gam m a Exposure Rate (Table 1) ................................................... 4-1 4.2 Air Particulate G ross Beta Radioactivity (Table 2) .......................... 4-3 4.3 Airborne Iodine (Table 3) ................................................................ 4-3 4.4 Air Particulate Gam m a (Table 4A-D) .............................................. 4-5 4.5 Air Particulate Strontium (Table 5) .................................................. 4-5 4.6 Soil (Table 6) .................................................................................. 4-5 4.7 Cow Milk (Table 7) .......................................................................... 4-5 4.8 Goat Milk (Table 8) ......................................................................... 4-6 4.9 Pasture G rass and Feed (Table 9) ................................................. 4-6 4.10 W ell W ater (Table 10) ..................................................................... 4-7 4.11 Reservoir W ater (Table 11) ............................................................ 4-7 4.12 Fruits and Vegetables (Table 12) .................................................... 4-7 4.13 Broad Leaf Vegetation (Table 13) ................................................... 4-7 4.14 Seawater (Table 14) ....................................................................... 4-7 4.15 Bottom Sedim ent (Table 15) ........................................................... 4-9 4.16 Aquatic Flora (Table 16) ............................................................... 4-10 4.17 Fish (Tables 17A and 17B) ........................................................... 4-10 4.17.1 Flounder (Table 17A) ....................................................... 4-10 4.17.2 Fish - Other (Table 17B) .................................................. 4-10 4.18 Mussels (Table 18) ....................................................................... 4-10 4.19 Oysters (Table 19) ........................................................................ 4-11 4.20 Clam s (Table 20) .......................................................................... 4-12 4.21 Scallops (Table 21) ....................................................................... 4-12 4.22 Lobsters (Table 22) ....................................................................... 4-12
5. OFFSITE DOSE EQUIVALENT COMMITMENTS ........................................... 5-1
6. DISCUSSION .............................................................................................. 6-1
7. REFERENCES ............................................................................................ 7-1 APPENDIX A - LAND USE CENSUS FOR 2006 .................................................... A-1 APPENDIX B - DNC QA PROGRA M..................................................................... B-1 APPENDIX C -

SUMMARY

OF INTERLABORATORY COMPARISONS ............... C-1

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 0

4

-, '4 re P

- a.

-9 ~tt a r

-a-a

-r - -

.0-

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 EXECUTIVE

SUMMARY

INTRODUCTION This report summarizes the results of the Radiological Environmental Monitoring Program (REMP) conducted in the vicinity of Millstone Power Station (MPS) during the period from January 1 to December 31, 2006. This document has been prepared in accordance with the requirements of Millstone Unit 2 and 3 Technical Specifications.

The REMP has been established to monitor the radiation and radioactivity released to the environment as a result of Millstone Station's operation. This program, initiated in April 1967, includes the collection, analysis, and evaluation of radiological data in order to assess the impact of Millstone Station on the environment and on the general public.

SAMPLING AND ANALYSIS The environmental sampling media collected in the vicinity of MPS and at distant locations included air particulate filters, charcoal cartridges, soil, goat milk, pasture grass, hay, well water, broadleaf vegetation, fruits, vegetables, seawater, bottom sediment, aquatic flora, fish, mussels, oysters, clams and lobster.

During 2006, there were 1094 samples collected from the atmospheric, aquatic, and terrestrial environments. In addition, 175 exposure measurements were obtained using environmental thermoluminescent dosimeters (TLDs).

A small number of inadvertent issues were encountered in 2006 in the collection of environmental samples in accordance with the Millstone Radiological Effluent Monitoring and Offsite Dose Calculation Manual (REMODCM). One of 160 required TLDs was unaccounted for during the quarterly retrieval process. The pole to which the missing TLD was attached was removed by CL&P and could not be found. Additional TLDs were collected to provide the information to assess ambient radiation levels in the vicinity of Millstone Station. Equipment failures and power outages resulted in a small number of instances in which lower than normal sampling volumes were collected at the airborne monitioring stations. In no cases were sampling outages of a duration to not yield a sample. All 416 air particulate and charcoal cartridges were collected and analyzed as required. A full description of all discrepancies encountered with the environmental monitoring program is presented in the Notes for the Data Tables of this report.

There were 1340 analyses performed on the environmental media samples. The AREVA-NP Environmental Laboratory of Westboro, MA, performed these analyses.

Samples were analyzed as required by the Millstone REMODCM.

LAND USE CENSUS The annual land use census in the vicinity of Millstone Station was conducted as required by the Millstone REMODCM between July 15 and December 31, 2006.

Although only vegetable gardens having an area of more than 500 square feet need to be identified, due to the difficulty of measuring individual gardens, all gardens identified by a drive-by survey are listed in Appendix A. No new milk or meat animals were located during the census. Millstone also performs monthly broad leaf sampling that may be used in lieu of the garden census.

i

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 RADIOLOGICAL IMPACT TO THE ENVIRONMENT Most samples collected as part of the Millstone REMP continued to contain detectable amounts of naturally-occurring and man-made radioactive materials. No station effects were detected in terrestrial media. Offsite ambient radiation measurements using environmental TLDs beyond the site boundary ranged between 46 and 78 milliRoentgens per year. The range of ambient radiation levels observed with the TLDs is consistent with natural background radiation levels for Connecticut.

Monitoring of the aquatic environment in the area of the discharge indicated the presence of the following station related radionuclides: Cobalt-60, Silver-i 1Om, and Tritium. The predominant radioactivity was from non-plant related sources, such as fallout from nuclear weapons tests and naturally occurring radionuclides.

RADIOLOGICAL IMPACT TO THE GENERAL PUBLIC During 2006, radiation doses to the general public as a result of Millstone Station's operation continued to be well below the federal limits and much less than the dose due to other sources of man-made (e.g., X-rays, medical) and naturally-occurring (e.g.,

cosmic, radon) radiation.

The calculated total body dose to the maximally exposed member of the general public from radioactive effluents and ambient radiation resulting from MPS operations for 2006 was about 0.24 mrem for the year. This conservative estimate is well below the EPA's annual dose limit to any member of the general public and is a fraction of a percent of the typical dose received from natural and man-made radiation.

CONCLUSIONS The 2006 Radiological Environmental Monitoring Program for Millstone Station resulted in the collection and analysis of over a thousand environmental samples and measurements. The data obtained were used to determine the impact of Millstone Station's operation on the environment and on the general public.

An evaluation of direct radiation measurements, environmental sample analyses, and dose calculations indicates all applicable federal criteria were met. Furthermore, radiation levels and resulting doses were a small fraction of those attributed to natural and man-made background radiation.

Based on this information, there is no significant radiological impact on the environment or on the general public due to Millstone Station's operation.

ii

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006

1. INTRODUCTION This section provides an overview of the Millstone Power Station Radiological Environmental Monitoring Program. It also includes background information to allow a reader to have an informed understanding of radiation and nuclear power operation.

1.1 Overview The Radiological Environmental Monitoring Program for 2006 performed by Dominion Nuclear Company for Millstone Nuclear Power Station (MPS) is discussed in this report.

Since the operation of a nuclear power plant results in the release of small amounts of radioactivity and low levels of radiation, the Nuclear Regulatory Commission (NRC) requires a program to be established to monitor radiation and radioactivity in the environment (Reference 1). This report, published annually per Millstone Station's Technical Specifications (section 6.9.1.6 for Unit 2 and Section 6.9.1.3 for Unit 3),

summarizes the results of measurements of radiation and radioactivity in the environment in the vicinity of the Millstone Station and at distant locations during the period January 1 to December 31, 2006.

The Radiological Environmental Monitoring Program consists of taking radiation measurements and collecting samples from the environment, analyzing them for radioactivity content, and interpreting the results. With emphasis on the critical radiation exposure pathways to humans, samples from the aquatic, atmospheric, and terrestrial environments are collected. These samples include, but are not limited to: air, soil, goat milk, pasture grass, hay, well water, broadleaf vegetation, fruits, vegetables, seawater, bottom sediment, aquatic flora, fish, mussels, oysters, clams and lobster.

Thermoluminescent dosimeters (TLDs) are placed in the environment to measure gamma radiation levels. The TLDs are processed and the environmental samples are analyzed to measure the very low levels of radiation and radioactivity present in the environment as a result of MPS operation and other natural and man-made sources.

These results are reviewed by MPS's radiological staff and have been reported semiannually or annually to the Nuclear Regulatory Commission and others for over 30 years.

In order to more fully understand how a nuclear power plant impacts humans and the environment, background information on radiation and radioactivity, natural and man-made sources of radiation, reactor operations, radioactive effluent controls, and radiological impact on humans is provided. It is believed that this information will assist the reader in understanding the radiological impact on the environment and humans from the operation of Millstone Station.

1.2 Radiation and Radioactivity All matter is made of atoms. An atom is the smallest part into which matter can be broken down and still maintain all its chemical properties. Nuclear radiation is energy, in the form of waves or particles that is given off by unstable, radioactive atoms.

1-1

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Radioactive material exists naturally and has always been a part of our environment.

The earth's crust, for example, contains radioactive uranium, radium, thorium, and potassium. Some radioactivity is a result of nuclear weapons testing. Examples of radioactive fallout that is normally present in environmental samples are cesium-137 and strontium-90. Some examples of radioactive materials released from a nuclear power plant are cesium-1 37, iodine-131, strontium-90, and cobalt-60.

Radiation is measured in units of millirem, much like temperature is measured in degrees. A millirem (mrem) is a measure of the biological effect of the energy deposited in tissue. The natural and man-made radiation dose received in one year by the average American is 300 to 400 mrem (References 2, 3, 4,5).

Radioactivity is measured in curies. A curie is that amount of radioactive material needed to produce 37,000,000,000 nuclear disintegrations per second. This is an extremely large amount of radioactivity in comparison to environmental radioactivity.

That is why radioactivity in the environment is measured in picocuries. One picocurie (pCi) is equal to one trillionth of a curie.

1.3 Sources of Radiation As mentioned previously, naturally occurring radioactivity has always been a part of our environment. Table 1.3 shows the sources and doses of radiation from natural and man-made sources.

Table 1.3 Radiation Sources and Corresponding Doses NATURAL MAN-MADE Radiation Dose Radiation Dose Source (millirem/yar Source (milliremyar Cosmic/cosmogenic 28 Medical/Dental X-Rays 39 Internal (in the body) 40 Nuclear Medicine 14 Terrestrial

  • 16 Consumer Products 10 Radon/Thoron 200 Weapons Fallout 1 Nuclear Power Plants 1 Approximate Total 284 Approximate Total T -60
  • Atlantic and Gulf Costal Plain Cosmic radiation from the sun and outer space penetrates the earth's atmosphere and continuously bombards us with rays and charged particles. Some of this cosmic radiation interacts with gases and particles in the atmosphere, making them radioactive in turn. These radioactive byproducts from cosmic ray bombardment are referred to as cosmogenic radionuclides. Isotopes such as beryllium-7 and carbon-14 are formed in this way. Exposure to cosmic and cosmogenic sources of radioactivity results in about 30 mrem of radiation dose per year.

1-2

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Additionally, natural radioactivity is in our body and in the food we eat (about 40 millirem/yr), the ground we walk on (about 30 millirem/yr) and the air we breathe (about 200 millirem/yr). The majority of a person's annual dose results from exposure to radon and thoron in the air we breathe. These gases and their radioactive decay products arise from the decay of naturally occurring uranium, thorium and radium in the soil and building products such as brick, stone, and concrete. Radon and thoron levels vary greatly with location, primarily due to changes in the concentration of uranium and thorium in the soil. Residents at some locations in Colorado, New York, Pennsylvania, New Jersey and even Connecticut have a higher annual dose as a result of higher levels of radon/thoron gases in these areas. In total, these various sources of naturally-occurring radiation and radioactivity contribute to a total dose of about 300 mrem per year.

In addition to natural radiation, we are normally exposed to radiation from a number of man-made sources. The single largest doses from man-made sources result from therapeutic and diagnostic applications of x-rays and radiopharmaceuticals. The annual dose to an individual in the U.S. from medical and dental exposure is about 50 mrem.

Consumer products, such as televisions and smoke detectors, contribute about 10 mrem/yr. Much smaller doses result from weapons fallout (less than 1 mrem/yr) and nuclear power plants (less than 1 mrem/yr). Typically, the average person in the United States receives about 60 mrem per year from man-made sources.

1.4 Nuclear Reactor Operations Millstone Station generates about 2000 megawatts of electricity at full power, which provides approximately one-half of the power consumed in the State of Connecticut.

Unit 2 and Unit 3 are pressurized water reactors (Unit 1, which is permanently shutdown, was a boiling water reactor). The nuclear station is located on an approximate 500-acre site about 5 kilometers (three miles) west of New London, CT.

Commercial operation of Unit 2 began in December 1975 and Unit 3 in May 1986.

Millstone Station was operational during most of 2006, with the exception of a Unit 2 refueling outage, which was performed between October 7 and November 19. The resulting monthly capacity factors are presented in Table 1.4.

Nuclear-generated electricity is produced by many of the same techniques used for conventional oil and coal-generated electricity. Both systems use heat to boil water to produce steam. The steam turns a turbine, which turns a generator, p~roducing electricity. In both cases, the steam passes through a condenser where it changes back into water and recirculates back through the system. The cooling water source for Millstone Station is the Niantic Bay.

The key difference between nuclear power and conventional power is the source of heat used to boil the water. Conventional plants burn fossil fuels in a boiler, while nuclear plants make use of uranium in a nuclear reactor.

1-3

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 TABLE 1.4 MPS OPERATING CAPACITY FACTOR DURING 2006 (Based on rated reactor thermal power)

Month Unit 2 Percent Capacity Unit 3 Percent Capacity January 99.7% 100.4%

February 88.9% 100.4%

March 99.6% 100.7%

April 70.1% 100.5%

May 99.5% 100.5%

June 99.7% 99.8%

July 99.1% 98.9%

August 98.9% 98.6%

September 99.0% 99.2%

October 18.2% 97.7%

November 35.5% 99.6%

December 99.7% 99.7%

Annual Average 84.0% 99.6%

Inside the reactor, a nuclear reaction called fission takes place. Particles, called neutrons, strike the nucleus of a uranium-235 atom, causing it to split into fragments called radioactive fission products. The splitting of the atoms releases both heat and more neutrons. The newly-released neutrons then collide with and split other uranium atoms, thus making more heat and releasing even more neutrons, and on and on until the uranium fuel is depleted or spent. This process is called a chain reaction.

The operation of a nuclear reactor results in the release of small amounts of radioactivity and low levels of radiation. The radioactivity originates from two major sources, radioactive fission products and radioactive activation products.

Radioactive fission products, as illustrated in Figure 1.4-1 (Reference 6), originate from the fissioning of the nuclear fuel. These fission products get into the reactor coolant from their release by minute amounts of uranium on the outside surfaces of the fuel cladding, by diffusion through the fuel pellets and cladding and, on occasion, through defects or failures in the fuel cladding. These fission products circulate along with the reactor coolant water and will deposit on the internal surfaces of pipes and equipment.

The radioactive fission products on the pipes and equipment emit radiation. Examples of some fission products are krypton-85 (Kr-85), strontium-90 (Sr-90), iodine-131 (I-131), xenon-1 33 (Xe-1 33), and cesium-1 37 (Cs-1 37).

1-4

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Nuclear Fission Fission is the splitting of the uranium-235 atom by a neutron to release heat and more neutrons, creating a chain reaction.

Radiation and fission products are by-products of the process.

Radiation Uranium Netrtons Radiation Neutron S0.-

Uranium Neutrons Uranium Fission Products Figure 1.4-1 Radioactive Fission Product Formation 1-5

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Radioactive activation products (see Figure 1.4-2), on the other hand, originate from two sources. The first is by neutron bombardment of the hydrogen, oxygen and other gas (helium, argon, nitrogen) molecules in the reactor cooling water. The second is a result of the fact that the internals of any piping system or component are subject to minute yet constant corrosion from the reactor cooling water. These minute metallic particles (for example: nickel, iron, cobalt, or magnesium) are transported through the reactor core into the fuel region, where neutrons may react with the nuclei of these particles, producing radioactive products. So, activation products are nothing more than ordinary naturally-occurring atoms that are made unstable or radioactive by neutron bombardment. These activation products circulate along with the reactor coolant water and will deposit on the internal surfaces of pipes and equipment. The radioactive activation products on the pipes and equipment emit radiation. Examples of some activation products are manganese-54 (Mn-54), iron-59 (Fe-59), cobalt-60 (Co-60), and zinc-65 (Zn-65).

-0Q Neutron Stable Radioactive Cobalt Nucleus Cobalt Nucleus Figure 1.4-2 Radioactive Activation Product Formation At Millstone Nuclear Power Station there are five independent protective barriers that confine these radioactive materials. These five barriers, which are shown in Figure 1.4-3 (Reference 6), are:

0 fuel pellets; 0 fuel cladding; 0 reactor vessel and piping; 0 primary containment and, 0 secondary containment (enclosure building).

1-6

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 SIMPLIFIED DIAGRAM OF A PRESSURIZED WATER REACTOR Figure 1.4-3 The ceramic uranium fuel pellets provide the first barrier. Most of the radioactive fission products are either physically trapped or chemically bound between the uranium atoms, where they will remain. However, a few fission products that are volatile or gaseous may diffuse through the fuel pellets into small gaps between the pellets and the fuel cladding.

The second barrier, the fuel cladding, consists of zirconium alloy tubes that confine the fuel pellets. The small gaps between the fuel and the cladding contain the noble gases and volatile iodines that are types of radioactive fission products. This radioactivity can diffuse to a small extent through the fuel cladding into the reactor coolant water.

1-7

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 The third barrier consists of the reactor pressure vessel, steel piping and equipment that confine the reactor cooling water. The reactor pressure vessel, which holds the reactor fuel, is typically a steel tank 40 feet high by 14 feet in diameter with walls about five to nine inches thick. These vessels and associated piping provide containment for radioactivity in the primary coolant and the reactor core. However, during the course of operations and maintenance, small amounts of radioactive fission and activation products can escape through valve leaks or upon breaching of the primary coolant system for maintenance.

The fourth barrier is the primary containment. It is a cylindrical enclosure with approximately five-foot thick steel reinforced concrete walls lined by steel on the inside.

Small amounts of radioactivity may be released from primary containment during operation to maintain proper containment pressure and during maintenance and refueling outages.

The fifth barrier is the secondary containment or enclosure building. The enclosure building is a steel building that surrounds the primary containment. This barrier is an additional safety feature at Millstone's reactor units to contain radioactivity that may escape from the primary containment. This enclosure building is equipped with a filtered ventilation system that is used when needed to reduce the radioactivity that escapes from the primary containment.

The five barriers confine most of the radioactive fission and activation products.

However, small amounts of radioactivity do escape via mechanical failures and maintenance on valves, piping, and equipment associated with the reactor cooling water system. The small amounts of radioactive liquids and gases that do escape the various containment systems are further controlled by the liquid purification and ventilation filtration systems. Also, prior to a release to the environment, control systems exist to collect and purify the radioactive effluents in order to reduce releases to the environment to as low as is reasonably achievable. The control of radioactive effluents at Millstone Station will be discussed in more detail in the next section.

1.5 Radioactive Effluent Control The small amounts of radioactive liquids and gases that might escape the first two barriers are purified in the liquid and gaseous waste treatment systems, then monitored for radioactivity, and released only if the radioactivity levels are below the federal release limits.

Radioactivity released from the liquid effluent system to the environment is limited, controlled, and monitored by a variety of systems and procedures which include:

" reactor water cleanup system;

" liquid radwaste treatment system;

  • sampling and analysis of the liquid radwaste tanks; and,
  • liquid waste effluent discharge radioactivity monitor.

1-8

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 The purpose of the reactor water cleanup system is to continuously purify the reactor cooling water by removing radioactive atoms and non-radioactive impurities that may become activated by neutron bombardment. A portion of the reactor coolant water is diverted from the primary coolant system and is directed through ion exchange resins where radioactive elements, dissolved and suspended in the water, are removed through chemical processes. The net effect is a substantial reduction of the radioactive material that is present in the primary coolant water and consequently the amount of radioactive material that might escape from the system.

Reactor cooling water that might escape the primary cooling system and other radioactive water sources are collected in floor and equipment drains. These drains direct this radioactive liquid waste to large holdup tanks. The liquid waste collected in the tanks is purified again using the liquid radwaste treatment system, which consists of a filter and ion exchange resins.

Processing of liquid radioactive waste results in large reductions of radioactive liquids discharged into Niantic Bay. Wastes processed through liquid radwaste treatment can be purified and when necessary the processed liquid is re-used in plant systems.

Prior to release, the radioactivity in the liquid radwaste tank is sampled and analyzed to determine if the level of radioactivity is below the release limits and to quantify the total amount of radioactive liquid effluent that would be released. If the levels are below the federal release limits, the tank is drained to the liquid effluent discharge header.

This liquid waste effluent discharge line is provided with a shielded radioactivity monitor.

This detector is connected to a radiation level meter and a recorder in the Control Room. The radiation alarm is set so that the detector will alarm before radioactivity levels exceed the release limits. The liquid effluent discharge header has an isolation valve. If an alarm is received, the liquid effluent discharge valve will automatically close, thereby terminating the release to the Niantic Bay and preventing any liquid radioactivity from being released that may exceed the release limits. An audible alarm notifies the Control Room operator that this has occurred.

Some liquid waste sources, which have a low potential for containing radioactivity, and/or may contain very low levels of contamination, may be discharged directly to the Long Island Sound. One such source of liquid is the turbine building sump. However, periodic representative samples are collected for analysis of radioactivity content to track the amounts of radioactivity being discharged.

Another means for adjusting liquid effluent concentrations to below federal limits is by mixing plant cooling water from the condenser with the liquid effluents in the discharge canal. This larger volume of cooling water further dilutes the radioactivity levels far below the release concentration limits.

The preceding discussion illustrates that many controls exist to reduce the radioactive liquid effluents released to the Niantic Bay to as far below the release limits as is reasonably achievable.

Radioactive releases from the radioactive gaseous effluent system to the environment are limited, controlled, and monitored by a variety of systems and procedures which include:

1-9

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006

" containment building ventilation system;

" containment building vent effluent radioactivity monitor;

" sampling and analysis of containment building vent and purge effluents;

" process gas treatment system;

" auxiliary building (and engineered safeguards and fuel building for Unit 3) ventilation system;

" stack and vent effluent radioactivity monitors;

" sampling and analysis of stack and vent effluents;

" process radiation monitors; and

" steam jet air ejector (SJAE) monitor The primary sources of gaseous radioactive waste are degassing of the primary coolant, gaseous liquid drains, and gaseous vents. Additional sources of gaseous waste activity include ventilation air released from the auxiliary building and purging and venting of the containment building. The radiation level meter and recorders for the effluent radioactivity monitors are located in the Control Room. The plant process computer aids in tracking the monitor readings. To supplement the information continuously provided by the detector, air samples are taken periodically from the containment, stack and vents. These samples are analyzed to quantify the total amount of tritium and radioactive gaseous and particulate effluents released.

Gases from the primary coolant are held up in waste gas decay tanks for decay at Unit

2. Gaseous waste at Unit 3 is purified through a process gas system, consisting of a high high-efficiency particulate air filters and charcoal adsorber beds. Gases from periodic venting of the Unit 2 containment are released through a similar process system (Enclosure Building Filtration System) while gases from the Unit 3 containment vacuum pumps are released without treatment. If necessary, Unit 3 containment air can be filtered by an internal particulate and charcoal treatment system. Containment purges (purge is the forced ventilation process while containment vents are pressure releases) for Unit 2 are filtered by high-efficiency particulate filters while at Unit 3 these are not normally filtered. If necessary particulate and charcoal filters can be used for these purges.

The auxiliary building ventilation system provides for ventilation of the auxiliary building and enclosure building (and service building and contiguous areas, waste disposal building, and fuel building for Unit 3, for Unit 2 these are all part of the auxiliary building).

Normally, the air from the ventilation of these areas will exhaust through the ventilation vent (which has a particulate filter for Unit 2). If exhaust from these areas reaches a predetermined level, the ventilation flow can be diverted by operator control to a particulate and charcoal filtration system.

Therefore, for both liquid and gaseous releases, radioactive effluent control systems exist to collect and purify the radioactive effluents in order to reduce releases to the environment to as low as is reasonably achievable. The effluents are always monitored, sampled and analyzed to make sure that radioactivity levels are below the release limits.

If the release limits are being approached, isolation valves in some of the waste effluent lines will automatically shut to stop the release, or Control Room operators can implement procedures to ensure that federal regulatory limits are always met.

1-10

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 1.6 Radiological Impact on Humans The final step in the effluent control process is the determination of the radiological dose impact to humans and comparison with the federal dose limits to the public. This step is performed in three stages. As mentioned previously, the purpose of continuous radiation monitoring and periodic sampling and analysis is to measure the quantities of radioactivity being released to determine compliance with the radioactivity release limits.

This is the first stage for assessing releases to the environment.

The second stage is calculations of the dose impact to the general public from Millstone Station's radioactive effluents are performed. The purpose of these calculations is to periodically assess the doses to the general public resulting from radioactive effluents to ensure that these doses are being maintained as far below the federal dose limits as is reasonably achievable. This is the second stage for assessing releases to the environment.

The types and quantities of radioactive liquid and gaseous effluents released from Millstone Station during each given year are reported to the Nuclear Regulatory Commission annually in the Radiological Effluent Release Report (RERR). Similar to this report, the RERR is submitted annually to the Nuclear Regulatory Commission.

Section 5 of this report discusses the detailed dose calculations from the RERR and provides a comparison to REMP dose calculations. The liquid and gaseous effluents were well below the federal release limits and were a small percentage of the MPS REMODCM effluent control limits.

The measurements of the physical and chemical nature of the effluents are used to determine how the radionuclides will interact with the environment and how they can result in radiation exposure to humans. The environmental interaction mechanisms depend upon factors such as the hydrological (water) and meteorological (atmospheric) characteristics in the area. Information on the water flow, wind speed, wind direction, and atmospheric mixing characteristics are used to estimate how radioactivity will distribute and disperse in the ocean and the atmosphere.

The most important type of information that is used to evaluate the radiological impact on humans is data on the use of the environment. Information on fish and shellfish consumption, boating usage, beach usage, locations of cows and goats, locations of residences, locations of gardens, drinking water supplies, and other usage information are utilized to estimate the amount of radiation and radioactivity received by the general public.

The radiation exposure pathway to humans is the path radioactivity takes from its release point at Millstone Station to its effect on man.

There are three major pathways in which liquid effluents affect humans:

  • external radiation from liquid effluents that deposit and accumulate on the shoreline;

" external radiation from immersion in ocean water containing radioactive liquids; and,

  • internal radiation from consumption of fish and shellfish containing radioactivity absorbed from the liquid effluents.

1-11

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 There are six major ways in which gaseous effluents affect humans:

" external radiation from an airborne plume of radioactivity;

" internal radiation from inhalation of airborne radioactivity;

  • external radiation from deposition of radioactive effluents on soil;
  • ambient (direct) radiation from contained sources at the power plant;
  • internal radiation from consumption of vegetation containing radioactivity deposited on the vegetation from airborne deposition and absorbed from the soil due to ground deposition of radioactive effluents; and,

" internal radiation from consumption of milk and meat containing radioactivity deposited on forage that is eaten by cattle and other livestock.

In addition, ambient (direct) radiation emitted from contained sources of radioactivity at MPS contributes to radiation exposure in the vicinity of the plant. Small amounts of ambient radiation result from low-level radioactive waste being processed and stored at the site prior to shipping and disposal. Also, the operation of an ISFSI (Independent Spent Fuel Storage Installation, operation began in 2005) results in very small amounts of direct radiation at the site boundary.

The radiological dose impact on humans is based both on effluent analyses and modeling and on direct measurements of radiation and radioactivity in the environment.

When MPS-related radioactivity is detected in samples that represent a plausible exposure pathway, the resulting dose from such exposure is assessed (see Sections 4 and 5). However, the operation of Millstone Power Station results in releases of only small amounts of radioactivity, and, as a result of dilution in the atmosphere and ocean, even the most sensitive radioactivity measurement and analysis techniques cannot usually detect these tiny amounts of radioactivity above that which is naturally present in the environment. Therefore, radiation doses are calculated using radioactive effluent release data and computerized dose calculations that are based on conservative NRC-recommended models that tend to result in over-estimates of the resulting dose. These computerized dose calculations are performed by Dominion Nuclear personnel. These computer codes use the guidelines and methodology set forth by the NRC in Regulatory Guide 1.109 (Reference 7). The dose calculations are documented and described in detail in the Millstone Nuclear Power Station's Radiological Effluent Monitoring and Offsite Dose Calculation Manual (Reference 8), which has been reviewed by the NRC.

It should be emphasized that because of the conservative assumptions made in the computer code calculations, the maximum hypothetical dose to an individual is considerably higher than the dose that would actually be received by a real individual.

After dose calculations are performed, the results are compared to the federal dose limits for the public. The two federal agencies that are charged with the responsibility of protecting the public from radiation and radioactivity are the Nuclear Regulatory Commission (NRC) and The Environmental Protection Agency (EPA).

The NRC, in 10CFR 20.1301 (Reference 9) limits the levels of radiation to unrestricted areas resulting from the possession or use of radioactive materials such that they limit any individual to a dose of:

  • less than or equal to 100 mrem per year to the total body.

1-12

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 In addition to this dose limit, the NRC has established design objectives for nuclear plant licensees. Conformance to these guidelines ensures that nuclear power reactor effluents are maintained as far below the legal limits as is reasonably achievable.

The NRC, in 10CFR 50 Appendix I (Reference 10) establishes design objectives for the dose to a member of the general public from radioactive material in liquid effluents released to unrestricted areas to be limited to:

  • less than or equal to 3 mrem per year to the total body; and,
  • less than or equal to 10 mrem per year to any organ.

The air dose due to release of noble gases in gaseous effluents is restricted to:

  • less than or equal to 10 mrad per year for gamma radiation; and,
  • less than or equal to 20 mrad per year for beta radiation.

The dose to a member of the general public from iodine-1 31, tritium, and all particulate radionuclides with half-lives greater than 8 days in gaseous effluents is limited to:

a less than or equal to 15 mrem per year to any organ.

The EPA, in 40CFR190.10 Subpart B (Reference 11), sets forth the environmental standards for the uranium fuel cycle. During normal operation, the annual dose to any member of the public, at or beyond the site boundary, from the entire uranium fuel cycle shall be limited to:

  • less than or equal to 25 mrem per year to the total body;
  • less than or equal to 75 mrem per year to the thyroid; and,
  • less than or equal to 25 mrem per year to any other organ.

The summary of the 2006 radiological impact for Millstone Station and comparison with the EPA dose limits and Appendix I guidelines is presented in Section 5 of this report.

The third stage of assessing releases to the environment is the Radiological Environmental Monitoring Program (REMP). The description and results of the REMP at Millstone Power Station during 2006 is discussed in Sections 2 through 4 of this report.

1-13

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006

2. PROGRAM DESCRIPTION 2.1 Samplingl Schedule and Locations The sample locations and the sample types and frequency of analysis are given in Tables 2-1 and 2-2 and Figures 2.1 and 2.2. The program as described on Table 2-2 only lists the required samples as specified in the Radiological Effluent Monitoring and Offsite Dose Calculation Manual. However, in order to identify the locations of the extra samples, all locations (both required and extra) are listed in Table 2-1 and shown on the figures.

2-1

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 2-1 Environmental Monitorina Proaram Samnlina Tvwes and Locations Location Direction & Distance Number* Location Name From Release Point** Sample Types 1-1 On-site - Old Millstone Rd. 0.6 Mi, NNW TLD, Air Particulate, Iodine, Vegetation 2-1 On-site - Weather Shack 0.3 Mi, S TLD, Air Particulate, Iodine 3-1 On-site - Bird Sanctuary 0.3 Mi, NE TLD, Air Particulate, Iodine, Soil 4-1 On-site - Albacore Drive 1.0 Mi, N TLD, Air Particulate, Iodine, Soil 5-1 MP3 Discharge 0.1 Mi, SSE TLD 6-1 Quarry Discharge 0.3 Mi, SSE TLD 7-1 Environmental Lab Dock 0.3 Mi, SE TLD 8-1 Environmental Lab 0.3 Mi, SE TLD 9-1 Bay Point Beach 0.4 Mi, W TLD 10-1 Pleasure Beach 1.2 Mi, E TLD, Air Particulate, Iodine, Vegetation 11-1 New London Country Club 1.6 Mi, ENE TLD, Air Particulate, Iodine 12-C Fisher's Island, NY 8.0 Mi, ESE TLD 13-C Mystic, CT 11.5 Mi, ENE TLD 14-C Ledyard, CT 12.0 Mi, NE TLD, Soil 15-C Norwich, CT 14.0 Mi, N TLD, Air Particulate, Iodine 16-C Old Lyme, CT 8.8 Mi, W TLD 17-1 Site Boundary 0.5 Mi, NE Vegetation 21-1 Goat Location #1 2.0 Mi, N Milk 22-1 Goat Location #2 2.7 Mi, NE Milk 24-C Goat Location #4 29.0 Mi, NNW Milk 25-1 Within 10 Miles Within 10 Miles Fruits & Vegetables 26-C Beyond 10 Miles Beyond 10 Miles Fruits & Vegetables 27-1 Niantic 1.7 Mi, WNW TLD, Air Particulate, Iodine 28-1 Two Tree Island 0.8 Mi, SSE Mussels 29-1 West Jordan Cove 0.4 Mi, NNE Clams 30-1 Niantic Shoals 1.5 Mi, NNW Mussels 31-1 Niantic Shoals 1.8 Mi, NW Bottom Sediment, Oysters 31 -X Niantic Shoals 1.8 Mi, NW Scallops 32-1 Vicinity of Discharge < 0.1 Mi Bottom Sediment, Oysters, Lobster, Fish, Seawater 32-X Vicinity of Discharge <0.1 Mi Fucus 33-1 Seaside Point 1.8 Mi, ESE Bottom Sediment 33-X Seaside Point 1.8 Mi, ESE Fucus 34-1 Thames River Yacht Club 4.0 Mi, ENE Bottom Sediment 34-X Thames River Yacht club 4.0 Mi, ENE Oysters 35-1 Niantic Bay 0.3 Mi, WNW Lobster, Fish 35-X Niantic Bay 0.3 Mi, WNW Bottom Sediment, Clams, Fucus 36-1 Black Point 3.0 Mi, WSW Oysters 36-X Black Point 3.0 Mi. WSW Bottom Sediment. Fucus

  • Key: I - Indicator C - Control X - Extra - sample not required by REMODCM
    • The release points are the MP1 stack for terrestrial locations and the quarry cut for aquatic locations.

2-2

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Location Direction & Distance Number* Location Name From Release Point** Sample Types 37-C Giant's Neck 3.5 Mi, WSW Bottom Sediment, Oysters, Seawater 37-X Giant's Neck 3.5 Mi, WSW Lobster 38-1 Waterford Shellfish Bed #1 1.0 Mi, NW Clams 39-X Jordon Cove Bar 0.8 Mi, NE Bottom Sediment, Clams, Fucus 40-X Quarry Fish, Oysters 41-I Myrock Avenue 3.2 Mi, ENE TLD 42-1 Billow Road 2.4 Mi, WSW TLD 43-1 Black Point 2.6 Mi, SW TLD 44-1 Onsite - Schoolhouse 0.1 Mi, NNE TLD 45-1 Onsite Access Road 0.5 Mi, NNW TLD 46-1 Old Lyme - Hillcrest Ave. 4.6 Mi, WSW TLD 47-1 East Lyme - W. Main St. 4.5 Mi, W TLD 48-1 East Lyme - Corey Rd. 3.4 Mi, WNW TLD 49-1 East Lyme - Society Rd. 3.6 Mi, NW TLD 50-1 East Lyme - Manwaring Rd. 2.1 Mi, W TLD 51-1 East Lyme - Smith Ave. 1.5 Mi, NW TLD 52-1 Waterford - River Rd. 1.1 Mi, NNW TLD 53-1 Waterford - Gardiners Wood 1.4 Mi, NNE TLD Rd.

55-1 Waterford - Magonk Point 1.8 Mi, ESE TLD 56-1 New London - Mott Ave. 3.7 Mi, E TLD 57-1 New London - Ocean Ave. 3.6 Mi, ENE TLD 59-1 Waterford -Miner Ave. 3.4 Mi, NNE TLD 60-1 Waterford - Parkway South 4.0 Mi, N TLD 61-1 Waterford - Boston Post Rd. 4.3 Mi, NNW TLD 62-1 East Lyme - Columbus Ave. 1.9 Mi, WNW TLD 63-1 Waterford - Jordon Cove Rd. 0.8 Mi, NE TLD 64-1 Waterford - Shore Rd. 1.1 Mi, ENE TLD 65-1 Waterford - Bank St. 3.2 Mi, NE TLD 66-X NAP Parking Lot - Fitness 0.4 Mi, NW TLD Center 67-X Golden Spur 4.7 Mi, NNW Bottom Sediment 68-Z Ram Island 9.6 Mi., ESE Oysters 69-X Pleasure Beach 0.8 Mi, E Bottom Sediment 71-1 Onsite Well Onsite Well Water 72-1 Onsite Well Onsite Well Water 73-X Site Switchyard Fence 0.3 Mi, N TLD 74-X Ball Field Foul Pole 0.6 Mi, N TLD 75-X Waterford - Windward Way & 0.5 Mi, NE TLD Shotgun 76-X Onsite Well - ISFSI Control Up-gradient of ISFSI Well Water 77-X Onsite Well - ISFSI Indicator Down-gradient of ISFSI Well Water 78-X Onsite Well - ISFSI Indicator Down-gradient of ISFSI Well Water 79-X Onsite Well Onsite Well Water 80-X Onsite Well Onsite Well Water 81 -X Onsite Well Onsite Well Water 90-C Thames River 4 Mi, E Fucus

  • Key: I - Indicator C - Control X or Z - Extra - sample not required
    • The release points are the MP1 stack for terrestrial locations and the quarry cut for aquatic locations.

2-3

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 2-2 Required Sampling Frequency & Type of Analysis Exposure Pathway No. of Sampling & Collection Type of Analysis and/or Sample ocation, Frequency

1. Gamma Dose 40a Quarterly Gamma Dose - Quarterly Environmental TLD
2. Airborne Particulate 8 Continuous sampler - weekly Gross Beta - Weekly filter change Gamma Spectrum - Quarterly on composite (by location), and on individual sample if gross beta is greater than 10 times the mean of the weekly control station's gross beta results
3. Airborne Iodine 8 Continuous sampler - weekly 1-131 - Weekly canister change
4. Vegetation 5 One sample near middle and Gamma Isotopic on each sample one near end of growing season
5. Milk 3 Semimonthly when animals are Gamma Isotopic and 1-131 on each on pasture; monthly at other sample; Sr-89 and Sr-90 on times. quarterly composite 5a. Pasture Grass 3 Sample as necessary to Gamma Isotopic and 1-131 on each substitute for unavailable milk sample
6. Sea Water 2 Continuous sampler with a Gamma Isotopic and Tritium on monthly collection at indicator each sample.

location. Quarterly at control location - Composite of 6 weekly grab samples.

6a. Well Water 2 Semiannual Gamma Isotopic and Tritium on each sample

7. Bottom Sediment 5 Semiannual Gamma Isotopic on each sample 7a. Soil 3 Annually Gamma Isotopic on each sample
8. Fin Fish-Flounder 2 Quarterly Gamma Isotopic on each sample and one other type of edible fin fish
9. Mussels 2 Quarterly Gamma Isotopic on each sample (edible portion)
10. Oysters 4 Quarterly Gamma Isotopic on each sample (edible portion)
11. Clams 2 Quarterly Gamma Isotopic on each sample (edible portion)
12. Lobster 2 Quarterly Gamma Isotopic on each sample (edible portion) I I II (a) Two or more TLDs or TLD with two or more elements per location.

2-4

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Figure 2.1 Millstone Sampling Locations 0 3

,sad LOSla Souind I TLD Monitoring (only)

  • TLD and Air Monitoring (particulates & iodine)
  • Terrestrial Monitoring (milk, grass, fruit & vebetables, soil, or leaves)
  • Aquatic Monitoring (seawater, sediment, flora, fish, mussel, oyster, clam, or lobster) 2-5

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Figure 2.2 Millstone Sampling Locations (Within 2 miles)

  • / N 2-6

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 2.2 Samples Collected During Report Period The following table summarizes the number of samples of each type collected and analyzed during 2006:

Number of Number of Technical Technical Specification Specification Number of Sample Type Required Samples Required Samples Extra Samples Analyzed Analyzed Gamma Exposure 160 1591 16 (Environmental TLD)

Air Particulates 424 424 0 Air Iodine 424 424 0 Soil 3 3 0 Goat Milk 54 142 0 Pasture Grass Variable 3 40 7 Fruit and Vegetables 8 8 1 Broad Leaf Vegetation 6 6 15 Sea Water 16 16 0 Well Water 4 4 15 Bottom Sediment 10 10 10 Aquatic Flora 0 0 22 Fish 16 134 2 Mussels 8 8 0 Oysters 16 159 8 Clams 8 8 9 Lobster 8 8 4 Total All Types 1,165 1,160 109 1 One TLD was missing since utility pole to which it was attached was replaced 2 Pasture grass sampled as necessary to substitute for unavailable milk. Hay or grain was substituted when grass was not available.

4 Depends upon availability of goat milk samples 5 Due to sample unavailability, not all required fish samples could be obtained 5 Due to broken cage, one oyster sample could not be obtained 2-7

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006

3. RADIOCHEMICAL RESULTS 3.1 Summary Table In accordance with the Radiological Effluent Monitoring and Offsite Dose Calculation Manual (REMODCM),Section I.F.1, a summary table of the radiochemical results has been prepared and is presented in Table 3-1.

The mean and range recorded are based only upon detectable measurements. The parentheses indicate the fraction of the measurements that are considered above the detection limit for each individual analysis.

A more detailed analysis of the data is given in Section 4.0 where a discussion of the variations in the data explains many aspects that are not evident in the Summary Table because of the basic limitation of data summaries. The data summaries include the extra

'X' samples collected throughout the year. These samples are taken to enhance the monitoring program, or are the results of special studies.

3-1

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM

SUMMARY

Page 1 of 16 DOCKETS 50-245, 50-336 & 50-339 Analysis Indicator Location with Highest Mean

  • Locations LLD Type Total Mean Name Distance Mean No Range I Directions Range TLD Gamima 175 - 7.94 (156/156) 08 0.3 mi 11.4 (4/4) 8.47 (19/19)

(uRlhr) Dose (4.4-11.6) SE (11-11.6) (5.94-10.6)

AP Gross Beta Gross 424 10 18 (369/371) 15-C 14.0 mi 18.3 (53/53) 18.3 (53/53)

(Ie-3 pCi/m3) Beta (4.5-34.5) N (6.1-33.5) (6.1-33.5)

Air Iodine 1-131 424 70 (0/371) < LLD (0/53)

(1e-3 pCi/m3)

AP Gamma Ba-140 32 - (0/28) - < LLD (0/4)

(Ie-3 pCi/m3)

Be-7 32 - 105(25/28) 03 0.3 mi 117(4/4) 94.8 (4/4)

(69-140) NE (96-139) (77-129)

Ce-141 32 - (0/28) - < LLD (0/4)

Ce- 144 32 - (0/28) - < LLD (0/4)

Co-58 32 - (0/28) - < LLD (0/4)

Co-60 32 - (0/28) - < LLD (0/4)

Cr-51 32 - (0/28) - < LLD (0/4)

Cs-134 32 50 (0/28) - < LLD (0/4)

Cs-137 32 60 (0/28) - < LLD (0/4)

Mn-54 32 - (0/28) - < LLD (0/4)

Nb-95 32 - (0/28) - < LLD (0/4)

Ru-103 32 - (0/28) - < LLD (0/4)

Ru-106 32 - (0/28) - < LLD (0/4)

Zr-95 32 - (0/28) - <LLD (0/4) 3-2

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM

SUMMARY

Page 2 of 16 DOCKETS 50-245, 50-336 & 50-339 Analysis Indicator Location with H1ighest Mean

  • Locations LLD Type Total Mean Name Distance Mean No Range Directions Range Soil Be-7 (0/2) - < LLD (0/1)

(pCi/g dry)

Ce-141 (0/2) - < LLD (0/1)

Ce-144 (0/2) - < LLD (0/1)

Co-58 (0/2) - < LLD (0/1)

Co-60 (0/2) - < LLD (0/1)

Cr-51 (0/2) - < LLD (0/1)

Cs-134 0.15 (0/2) - < LLD (0/1)

Cs-137 0.18 0.587 (2/2) 14-C 12.0 mi 1.12(1/1) 1.12(1/1)

(0.542-0.631) NE (1.12-1.12) (1.12-1.12)

Fe-59 (0/2) - < LLD (0/1)

K-40 11.2 (2/2) 14-C 12.0 mi 12.7(1/1) 12.7 (1/1)

(10.9-11.5) NE (12.7-12.7) (12.7-12.7)

Mn-54 (0/2) - < LLD (0/1)

Nb-95 (0/2) - < LLD (0/1)

Ru-1 03 (0/2) - < LLD (0/1)

Ru-106 (0/2) - < LLD (0/1)

Sb-125 (0/2) - < LLD (0/1)

Th-228 0.83 (2/2) 14-C 12.0 mi 1.3(1/1) 1.3 (1/1)

(0.66-1) NE (1.3-1.3) (1.3-1.3)

Zn-65 (0/2) < LLD (0/1)

Zr-95 (0/2) < LLD (0/1) 3-3

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM

SUMMARY

Page 3 of 16 DOCKETS 50-245, 50-336 & 50-339 Analysis

  • Indicator Location with Highest Mean Locations LLD Type Total L Mean Name Distance Mean No Range Directioni Range Goat Milk Ba-140 14 70 (0/6) < LLD (0/8)

(pCi/L)

Cs-134 14 15 (0/6) - < LLD (0/8)

Cs- 137 14 18 8.55(2/6) 24-C 29.0 mi 12.9 (1/8) 12.9 (1/8)

(7.7-9.4) NNW (12.9-12.9) (12.9-12.9) 1-131 14 1 (0/6) - < LLD (0/8)

K-40 14 - 1298(6/6) 24-C 29.0 mi 1685 (8/8) 1685 (8/8)

(950-1820) NNW (1380-1890) (1380-1890)

La-140 14 25 (0/6) - < LLD (0/8)

Sr-89 4 - (0/2) - < LLD (0/2)

Sr-90 4 - (0/2) - < LLD (0/2)

Pasture Grass Ba-140 47 - (0/35) - < LLD (0/12)

(Hay)

(pCi/g wet)

Be-7 47 1.6 (24/35) 24-C 29.0 mi 2.16 (7/12) 2.16 (7/12)

(0.26-3.08) NNW (0.8-3.74) (0.8-3.74)

Ce-141 47 (0/35) < LLD (0/12)

Ce-144 47 (0/35) < LLD (0/12)

Co-58 47 (0/35) < LLD (0/12)

Co-60 47 (0/35) < LLD (0/12)

Cr-51 47 (0/35) < LLD (0/12)

Cs-134 47 0.06 (0/35) < LLD (0/12)

Cs-137 47 0.08 0.02 (2/35) 24-C 29.0 mi 0.063 (1/12) 0.063 (1/12)

(0.02-0.02) NNW (0.063-0.063) (0.063-0.063)

Fe-59 47 (0/35) < LLD (0/12) 3-4

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM

SUMMARY

Page 4 of 16 DOCKETS 50-245, 50-336 & 50-339 Analysis Indicator Location with Highest Mean

  • Locations LLD Type Total Mean Name Distance Mean No Range I Directions Range Pasture Grass 1-131 47 0.06 (0135) < LLD (0/12)

(Hay)

(pCi/g wet)

K-40 47 - 6.77 (35/35) 24-C 29.0 mi 7.92 (12/12) 7.92 (12/12)

(2.69-20) NNW (4.15-15) (4.15-15)

La-140 47 (0/35) - < LLD (0/12)

Mn-54 47 - (0/35) - < LLD (0/12)

Nb-95 47 - (0/35) - < LLD (0/12)

Ru-103 47 - (0/35) - < LLD (0/12)

Ru-106 47 - (0/35) - < LLD (0/12)

Sb-125 47 - (0/35) - < LLD (0/12)

Th-228 47 - 0.105 (1/35) 22 2.7 mi 0.105 (1/20) (0/12)

(0.105-0.105) NE (0.105-0.105)

Zn-65 47 - (0/35) - < LLD (0/12)

Zr-95 47 - (0/35) - < LLD (0/12)

Well Water Ba-140 19 60 (0/19) - < LLD (0/0)

(pCi/L)

Be-7 19 - (0/19) - < LLD (0/0)

Co-58 19 15 (0/19) - < LLD (0/0)

Co-60 19 15 (0/19) - < LLD (0/0)

Cr-51 19 - (0/19) - < LLD (0/0)

Cs-134 19 15 (0/19) - < LLD (0/0)

Cs-137 19 18 (0/19) - < LLD (0/0) 3-5

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM

SUMMARY

Page 5 of 16 DOCKETS 50-245, 50-336 & 50-339 Analysis Indicator Location with Highest Mean

  • Locations Type Total L Mean Name Distance Mean No Range Directions Range Well Water Fe-59 19 30 (0/19) < LLD (0/0)

(pCi/L)

H-3 19 2000 (0/19) < LLD (0/0) 1-131 19 15 (0/19) < LLD (0/0)

K-40 19 (0/19) < LLD (0/0)

La-140 19 15 (0/19) < LLD (0/0)

Mn-54 19 15 (0/19) < LLD (0/0)

Nb-95 19 15 (0/19) < LLD (0/0)

Ru- 103 19 (0/19) < LLD (0/0)

Ru-106 19 (0/19) < LLD (0/0)

Sb-125 19 (0/19) < LLD (0/0)

Th-228 19 (0/19) < LLD (0/0)

Zn-65 19 30 (0/19) < LLD (0/0)

Zr-95 19 30 (0/19) < LLD (0/0)

Fruits & Ba-140 9 (0/5) < LLD (0/4)

Vegetables (pCi/g wet)

Be-7 9 0.415 (1/5) 25 10- mi 0.415(1/5) (0/4)

(0.415-0.415) (0.415-0.415)

Ce-141 9 (0/5) - < LLD (0/4)

Ce- 144 9 (0/5) < LLD (0/4)

Co-58 9 (0/5) < LLD (0/4) 3-6

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM

SUMMARY

Page 6 of 16 DOCKETS 50-245, 50-336 & 50-339 Analysis Indicator Location with Highest Mean

  • Locations LLD Type Total Mean Name Distance Mean No Range Directions Range Fruits & Co-60 9 (0/5) < LLD (0/4)

Vegetables (pCi/g wet)

Cr-51 - (0/5) < LLD (0/4)

Cs-134 0.06 (0/5) - < LLD (0/4)

Cs-137 0.08 0.039 (1/5) 25 10- mi 0.039(1/5) (0/4)

(0.039-0.039) (0.039-0.039)

Fe-59 - (0/5) - < LLD (0/4) 1-131 0.06 (0/5) - < LLD (0/4)

K-40 - 2.25 (5/5) 26-C 10+ mi 2.31 (4/4) 2.31 (4/4)

(0.69-4.21) (0.82-4.74) (0.82-4.74)

La-140 - (0/5) - < LLD (0/4)

Mn-54 - (0/5) - < LLD (0/4)

Nb-95 - (0/5) - < LLD (0/4)

Ru-103 - (0/5) - < LLD (0/4)

Ru-106 - (0/5) - < LLD (0/4)

Sb-125 - (0/5) - < LLD (0/4)

Th-228 - (0/5) - < LLD (0/4)

Zn-65 - (0/5) - < LLD (0/4)

Zr-95 - (0/5) - < LLD (0/4) 3-7

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM

SUMMARY

Page 7 of 16 DOCKETS 50-245, 50-336 & 50-339 Analysis Indicator Location with Highest Mean L Locations Type Total - Mean Name Distance Mean No Range Direction Range Broadleaf Ba-140 21 (0/21) < LLD (0/0)

Vegetation (pCi/g wet)

Be-7 21 - 1.62 (18/21) 17 0.5 mi 2.03 (7/7) (0/0)

(0.71-6.11) NE (0.78-6.11)

Ce-141 21 - (0/21) - < LLD (0/0)

Ce-144 21 - (0/21) - < LLD (0/0)

Co-58 21 - (0/21) - < LLD (0/0)

Co-60 21 - (0/21) - < LLD (0/0)

Cr-51 21 - (0/21) - < LLD (0/0)

Cs-134 21 0.06 (0/21) - < LLD (0/0)

Cs-137 21 0.08 0.182(1/21) 17 0.5 mi 0.182(1/7) (0/0)

(0.182-0.182) NE (0.182-0.182)

Fe-59 21 - (0/21) < LLD (0/0) 1-131 21 0.06 (0/21) - < LLD (0/0)

K-40 21 - 3.55 (21/21) 01 0.6 mi 3.77 (7/7) (0/0)

(2.08-4.15) NNW (3.46-4.15)

La-140 21 - (0/21) - < LLD (0/0)

Mn-54 21 - (0/21) - < LLD (0/0)

Nb-95 21 - (0/21) - < LLD (0/0)

Ru-103 21 - (0/21) - < LLD (0/0)

Ru-106 21 - (0/21) - < LLD (0/0)

Sb-125 21 - (0/21) - < LLD (0/0) 3-8

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM

SUMMARY

Page 8 of 16 DOCKETS 50-245, 50-336 & 50-339 Medium or Analysis Indicator Location with Highest Mean Control Non-Pathway Sampled JLLD Locations Locations Routine Reported (Units) Type Total Mean Name Distance Mean Mean Measure-I I No Range Direction Range Range ments Broadleaf Th-228 21 - 0.248 (3/21) 17 0.5 mi 0.248 (3/7) (0/0)

Vegetation (0.134-0.37) NE (0.134-0.37)

(pCi/g wet)

Zn-65 21 - (0/21) < LLD (0/0)

Zr-95 21 - (0/21) - < LLD (0/0)

Sea Water Ba- 140 16 60 (0/12) - < LLD (0/4)

(pCi/L)

Be-7 16 - (0/12) - < LLD (0/4)

Co-58 16 15 (0/12) - < LLD (0/4)

Co-60 16 15 (0/12) - < LLD (0/4)

Cr-51 16 - (0/12) - < LLD (0/4)

Cs-134 16 15 (0/12) - < LLD (0/4)

Cs-137 16 18 (0/12) - < LLD (0/4)

Fe-59 16 30 (0/12) - < LLD (0/4)

H-3 16 2000 489 (7/12) 32 489 (7/12) (0/4)

(290-770) (290-770) 1-131 16 15 (0/12) - < LLD (0/4)

K-40 16 - 277 (12/12) 32 277 (12/12) 246 (4/4)

(226-338) (226-338) (209-276)

La-140 16 15 (0/12) - < LLD (0/4)

Mn-54 16 15 (0/12) - < LLD (0/4)

Nb-95 16 15 (0/12) - < LLD (0/4)

Ru-103 16 - (0/12) - < LLD (0/4) 3-9

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM

SUMMARY

Page 9 of 16 DOCKETS 50-245, 50-336 & 50-339 Analysis Indicator Location with Highest Mean

  • Locations Type Total L Mean Name Distance Mean No Range Directioni Range Sea Water Ru-106 16 - (0/12) - < LLD (0/4)

(pCi/L)

Sb-125 16 - (0/12) - < LLD (0/4)

Th-228 16 - (0/12) - < LLD (0/4)

Zn-65 16 30 (0/12) - < LLD (0/4)

Zr-95 16 30 (0/12) - < LLD (0/4)

Bottom Sediment Ag-lil0m 20 - (0/18) - < LLD (0/2)

(pCi/g dry)

Be-7 20 - (0/18) - < LLD (0/2)

Co-58 20 - (0/18) - < LLD (0/2)

Co-60 20 0.097 (1/18) 39-X 0.8 mi 0.097(1/2) (0/2)

(0.097-0.097) NE (0.097-0.097)

Cr-51 20 - (0/18) < LLD (0/2)

Cs-134 20 0.15 (0/18) - < LLD (0/2)

Cs-137 20 0.18 0.141 (4/18) 39-X 0.8 mi 0.142(2/2) (0/2)

(0.096-0.183) NE (0.109-0.174)

Fe-59 20 - (0/18) < LLD (0/2) 1-131 20 - (0/18) - < LLD (0/2)

K-40 20 - 15 (18/18) 39-X 0.8 mi 17.3 (2/2) 14.3 (2/2)

(11.1-19.5) NE (15.1-19.5) (13.2-15.4)

Mn-54 20 (0/18) - < LLD (0/2)

Nb-95 20 - (0/18) - < LLD (0/2)

Ru-103 20 (0/18) - < LLD (0/2) 3-10 Ru-106 20 (0/18) - < LLD (0/2)

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM

SUMMARY

Page 10 of 16 DOCKETS 50-245, 50-336 & 50-339 Analysis Indicator Location with Highest Mean

  • Locations LLD Type Total Mean Name Distance Mean No Range I Directioni Range Bottom Sediment Sb-125 20 - (0/18) - < LLD (0/2)

(pCi/g dry)

Th-228 20 - 1.07 (15/18) 31 1.8 mi 2.1 (2/2) 0.394 (2/2)

(0.191-3.32) NW (0.87-3.32) (0.348-0.44)

Zn-65 20 - (0/18) < LLD (0/2)

Zr-95 20 - (0/18) < LLD (0/2)

Aquatic Flora Ag-110m 22 - (0/20) - < LLD (0/2)

(pCi/g wet)

Be-7 22 - 0.141 (4/20) 35-X 0.3 mi 0.246(1/4) 0.186(1/2)

(0.084-0.246) WNW (0.246-0.246) (0.186-0.186)

Co-58 22 - (0/20) - < LLD (0/2)

Co-60 22 - (0/20) - < LLD (0/2)

Cr-51 22 - (0/20) - < LLD (0/2)

Cs-134 22 - (0/20) - < LLD (0/2)

Cs-137 22 - (0/20) - < LLD (0/2)

Fe-59 22 - (0/20) - < LLD (0/2) 1-131 22 - 0.029 (4/20) 90-C 4.2 mi 0.107(2/2) 0.107 (2/2)

(0.018-0.05) ENE (0.072-0.142) (0.072-0.142)

K-40 22 - 5.78 (20/20) 90-C 4.2 mi 8.29 (2/2) 8.29 (2/2)

(3.71-10.3) ENE (6.43-10.1) (6.43-10.1)

Mn-54 22 - (0/20) - < LLD (0/2)

Nb-95 22 - (0/20) - < LLD (0/2)

Ru-103 22 - (0/20) - < LLD (0/2)

Ru-106 22 - (0/20) - < LLD (0/2) 3-11 Sb- 125 22 - (0/20) - < LLD (0/2)

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report

'Millstone Station 2006 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM

SUMMARY

Page II of 16 DOCKETS 50-245, 50-336 & 50-339 Analysis Indicator Location with Highest Mean

  • Locations Type Total L Mean Name Distance Mean No Range IDirectioni Range Aquatic Flora Th-228 22 - 0.051 (3/20) 90-C 4.2 mi 0.079 (2/2) 0.079 (2/2)

(pCi/g wet) (0.04-0.06) ENE (0.06-0.098) (0.06-0.098)

Zn-65 22 - (0/20) < LLD (0/2)

Zr-95 22 - (0/20) < LLD (0/2)

Fish-Flounder Ag-ll0m 6 - (0/6) < LLD (0/0)

(pCi/g wet)

Be-7 6 - (0/6) < LLD (0/0)

Co-58 6 0.13 (0/6) < LLD (0/0)

Co-60 6 0.13 (0/6) < LLD (0/0)

Cr-51 6 - (0/6) < LLD (0/0)

Cs-134 6 0.13 (0/6) < LLD (0/0)

Cs-137 6 0.15 (0/6) < LLD (0/0)

Fe-59 6 0.26 (0/6) < LLD (0/0) 1-131 6 - (0/6) < LLD (0/0)

K-40 6 - 3.8(6/6) 32 4.12 (3/3) (0/0)

(2.91-4.69) (3.7-4.69)

Mn-54 6 0.13 (0/6) < LLD (0/0)

Nb-95 6 - (0/6) < LLD (0/0)

Ru- 103 6 - (0/6) < LLD (0/0)

Ru-106 6 - (0/6) < LLD (0/0)

Sb-125 6 - (0/6) < LLD (0/0) 3-12 Th-228 6 - (0/6) < LLD (0/0)

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM

SUMMARY

Page 12 of 16 DOCKETS 50-245, 50-336 & 50-339 Analysis Indicator Location with Highest Mean

  • Locations I

Type Total LLD L Mean Name Distance Mean No Range Directioni Range Fish-Flounder Zn-65 0.26 (0/6) - < LLD (0/0)

(pCi/g wet)

Zr-95 - (0/6) - < LLD (0/0)

Fish-Other Ag-110m - (0/9) - < LLD (0/0)

(pCi/g wet)

Be-7 - (0/9) - < LLD (0/0)

Co-58 0.13 (0/9) - < LLD (0/0)

Co-60 0.13 (0/9) - < LLD (0/0)

Cr-51 - (0/9) - < LLD (0/0)

Cs-134 0.13 (0/9) - < LLD (0/0)

Cs-137 0.15 (0/9) - < LLD (0/0)

Fe-59 0.26 (0/9) - < LLD (0/0) 1-131 - (0/9) - < LLD (0/0)

K-40 - 3.77 (9/9) 35 0.3 mi 4.18 (3/3) (0/0)

(2.96-4.34) WNW (4.1-4.34)

Mn-54 0.13 (0/9) - < LLD (0/0)

Nb-95 - (0/9) - < LLD (0/0)

Ru-103 - (0/9) - < LLD (0/0)

Ru-106 - (0/9) - < LLD (0/0)

Sb-125 - (0/9) - < LLD (0/0)

Th-228 (0/9) - < LLD (0/0) 3-13 Zn-65 0.26 (0/9) - < LLD (0/0)

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM

SUMMARY

Page 13 of 16 DOCKETS 50-245, 50-336 & 50-339 Analysis Indicator Location with Highest Mean

  • Locations LLD Type Total Mean Name Distance Mean No Range Direction! Range Fish-Other Zr-95 - (0/9) < LLD (0/0)

(pCi/g wet)

Mussels Ag-1 l0m - (0/8) < LLD (0/0)

(pCi/g wet)

Be-7 - (0/8) < LLD (0/0)

Co-58 0.13 (0/8) < LLD (0/0)

Co-60 0.13 (0/8) < LLD (0/0)

Cr-51 - (0/8) < LLD (0/0)

Cs-134 0.13 (0/8) < LLD (0/0)

Cs-137 0.15 (0/8) < LLD (0/0)

Fe-59 0.26 (0/8) < LLD (0/0) 1-131 - (0/8) < LLD (0/0)

K-40 - 1.77 (8/8) 28 0.8 mi 1.8 (4/4) (0/0)

(1.47-2.12) SSE (1.56-2.12)

Mn-54 0.13 (0/8) < LLD (0/0)

Nb-95 - (0/8) < LLD (0/0)

Ru-103 - (0/8) < LLD (0/0)

Ru- 106 - (0/8) < LLD (0/0)

Sb-125 - (0/8) < LLD (0/0)

Th-228 - (0/8) < LLD (0/0)

Zn-65 0.26 (0/8) < LLD (0/0) 3-14 Zr-95 - (0/8) < LLD (0/0)

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM

SUMMARY

Page 14 of 16 DOCKETS 50-245, 50-336 & 50-339 Analysis Indicator Location with Highest Mean

  • Locations Type Total Mean Name Distance Mean No Range Directioni Range Oysters Ag-110m 23 - 0.068 (5/19) 40-X 0.072 (3/4) (0/4)

(pCi/g wet) (0.046-0.091) (0.061-0.091)

Be-7 23 - (0/19) - < LLD (0/4)

Co-58 23 0.13 (0/19) - - < LLD (0/4)

Co-60 23 0.13 (0/19) - - < LLD (0/4)

Cr-51 23 - (0/19) - - < LLD (0/4)

Cs-134 23 0.13 (0/19) - - < LLD (0/4)

Cs-137 23 0.15 (0/19) - - < LLD (0/4)

Fe-59 23 0.26 (0/19) - - < LLD (0/4) 1-131 23 - (0/19) - - < LLD (0/4)

K-40 23 - 1.9 (18/19) 34-X 4.0 mi 2.12 (4/4) 2.02 (4/4)

(0.99-2.42) ENE (1.86-2.4) (1.87-2.34)

Mn-54 23 0.13 (0/19) - < LLD (0/4)

Nb-95 23 - (0/19) - - < LLD (0/4)

Ru- 103 23 - (0/19) - - < LLD (0/4)

Ru-106 23 - (0/19) - - < LLD (0/4)

Sb-125 23 - (0/19) - - < LLD (0/4)

Th-228 23 - (0/19) - - < LLD (0/4)

Zn-65 23 0.26 (0/19) - - < LLD (0/4)

Zr-95 23 - (0/19) - - < LLD (0/4) 3-15

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM

SUMMARY

Page 15 of 16 DOCKETS 50-245, 50-336 & 50-339 I

Clams Ag-110m - (0/17) - < LLD (0/0)

(pCi/g wet)

Be-7 - (0/17) - < LLD (0/0)

Co-58 0.13 (0/17) - < LLD (0/0)

Co-60 0.13 (0/17) - < LLD (0/0)

Cr-51 - (0/17) - < LLD (0/0)

Cs-134 0.13 (0/17) - < LLD (0/0)

Cs-137 0.15 (0/17) - < LLD (0/0)

Fe-59 0.26 (0/17) - < LLD (0/0) 1-131 - (0/17) - < LLD (0/0)

K-40 - 2.18 (17/17) 39-X 0.8 mi 2.85 (4/4) (0/0)

(1.48-5.46) NE (1.48-5.46)

Mn-54 0.13 (0/17) - < LLD (0/0)

Nb-95 - (0/17) - < LLD (0/0)

Ru-103 - (0/17) - < LLD (0/0)

Ru-106 - (0/17) - < LLD (0/0)

Sb-125 - (0/17) - < LLD (0/0)

Th-228 - (0/17) - < LLD (0/0)

Zn-65 0.26 (0/17) - < LLD (0/0)

Zr-95 - (0/17) - < LLD (0/0) 3-16

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 RADIOLOGICAL ENVIRONMENTAL MONITORING PROGRAM

SUMMARY

Page 16 of 16 DOCKETS 50-245, 50-336 & 50-339 Analysis

  • Indicator Location with IHighest Mean Locations Type Total L Mean Name Distance Mean No Range I Directionj Range Lobsters (Crabs) Ag-1 10m - (0/12) -- < LLD (0/0)

(pCi/g wet)

Be-7 - (0/12) - - < LLD (0/0)

Co-58 0.13 (0/12) - - < LLD (0/0)

Co-60 0.13 (0/12) - - < LLD (0/0)

Cr-51 - (0/12) - - < LLD (0/0)

Cs-134 0.13 (0/12) - - < LLD (0/0)

Cs-137 0.15 (0/12) - - < LLD (0/0)

Fe-59 0.26 (0/12) - - < LLD (0/0) 1-131 - (0/12) - - < LLD (0/0)

K-40 - 2.44(12/12) 35 0.3 mi 2.71 (4/4) (0/0)

(2.05-3.66) WNW (2.17-3.66)

Mn-54 0.13 (0/12) - - < LLD (0/0)

Nb-95 - (0/12) - - < LLD (0/0)

Ru- 103 - (0/12) - - < LLD (0/0)

Ru- 106 - (0/12) - - < LLD (0/0)

Sb-125 - (0/12) - - < LLD (0/0)

Th-228 - (0/12) - - < LLD (0/0)

Zn-65 0.26 (0/12) - - < LLD (0/0)

Zr-95 - (0/12) - - < LLD (0/0) 3-17

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 NOTES FOR TABLE 3-1 For gamma measurements the Minimum Detectable Level (MDL) - the Lower Limit of Detection (LLD) / 2.33. For all others, MDL = 2 x (the standard deviation of the background). These MDLs are based on the absence of large amounts of interfering activity (excluding naturally occurring radionuclides). Deviations by factors of 3 to 4 can occur.

The LLD at a confidence level of 95% is the smallest concentration of radioactive material in a sample that will be detected with a 5% probability of falsely concluding that a blank observation represents a "real" signal.

For a particular measurement system (which may include radiochemical separation):

LLD = 4.66Sb E

  • V
  • 2.22
  • Y
  • exp (-2A0 where, LLD is the lower limit of detection as defined above (as pCi per unit mass or volume)

Sb is the standard deviation of the background counting rate or of the counting rate of a blank sample as appropriate (as counts per minute)

E is the counting efficiency (as counts per transformation)

V is the sample size (in units of mass or volume) 2.22 is the number of transformation per minute per picoCurie Y is the fractional radiochemical yield (when applicable)

A is the radioactive decay constant for the particular radionuclide Xt is the elapsed time between sample collection (or end of the sample collection period) and time of counting The LLD is defined as a priori (before the fact) limit representing the capability of a measurement system and not an a posteriori (after the fact) limit for a particular measurement.

Analyses shall be performed in such a manner that the stated LLDs will be achieved under routine conditions. Occasionally background fluctuations, unavoidably small sample sizes, the presence of interfering nuclides, or other uncontrollable circumstances may render these a priori LLDs unachievable. In such cases, the contributing factors will be identified and described in the Annual Radiological Environmental Operating Report. As shown in the equation above, for composite samples taken over a period of time, the LLD is decayed to the end of the sample period.

    • LLD for leafy vegetables.

LLD from the end of the sample period.

3-18

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 3.2 Data Tables The data reported in this section are strictly counting statistics. The reported error is two times the standard deviation (2a) of the net activity. Unless otherwise noted, the overall error (counting, sample size, chemistry, errors, etc.) is estimated to be 2 to 5 times that listed. Results are considered positive when the measured value exceeds 1.5 times the listed 2a error (i.e., the measured value exceeds 3a).

Because of counting statistics, negative values, zeros and numbers below the Minimum Detectable Level (MDL) are statistically valid pieces of data. For the purposes of this report, in order to indicate any background biases, all the valid data are presented. This practice was recommended by Health and Safety Laboratory (HASL) ("Reporting of Analytical Results from HASL," letter by Leo B. Higginbotham), NUREG 0475 and NUREG/CR-4007 (Sept. 1984). In instances where zeros are listed after significant digits, this is an artifact of the computer data-handling program.

Data are given according to sample type as indicated below.

1. Gamma Exposure Rate
2. Air Particulates, Gross Beta Radioactivity
3. Air Particulates, Weekly 1-131
4. Air Particulates, Quantitative Gamma Spectra
5. Air Particulates, Quarterly Strontium*
6. Soil
7. Milk - Dairy Farms*
8. Milk - Goat Farms
9. Pasture Grass
10. Well Water
11. Reservoir Water*
12. Fruits & Vegetables
13. Broad Leaf Vegetation
14. Seawater
15. Bottom Sediment
16. Aquatic Flora
17. Fin Fish
18. Mussels
19. Oysters
20. Clams
21. Scallops*
22. Lobster (and Crabs)

This type of sampling or analysis was not performed; therefore there is no table.

3-19

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 1, Quarterly TLD Gamma Exposure Rate (uR/hr) Page I of 2 ILocation First Second Third Fourth Average

.1Number Quarter Quarter Quarter Quarter +/-2 s.d. I 01 8.28 +/- 0.31 8.71 +/- 0.20 8.41 A+/-0.35 8.08 +/- 0.24 8.37 +/- 0.46 02 10.27 +/- 0.53 10.37 +/- 0.40 10.01 +/- 0.35 9.84 +/- 0.45 10.12 +/- 0.42 03 7.00 +/- 0.28 6.90 +/- 0.34 6.42 +/- 0.29 6.95 +/- 0.25 6.82 +/- 0.46 04 8.42 +/- 0.20 8.61 +/- 0.20 7.95 +/- 0.42 8.59 +/- 0.25 8.39 +/- 0.53 05 9.73 +/- 0.31 9.73 +/- 0.50 9.14 +/- 0.43 9.42 +/- 0.28 9.51 +/- 0.49 06 8.69 +/- 0.20 8.79 +/- 0.26 7.91 +/- 0.38 8.31 +/- 0.23 8.43 +/- 0.69 07 5.24 +/- 0.18 5.25 +/- 0.25 4.40 +/- 0.31 4.88 +/- 0.17 4.94 +/- 0.69 08 11.62 +/-0.35 11.63 +/- 0.26 11.30 +/- 0.92 .11.03 +/-0.52 11.40 +/- 0.50 09 9.23 +/- 0.19 9.61 +/- 0.57 9.21 +/- 0.36 9.38 +/- 0.29 9.36 +/- 0.32 10 10.29 +/- 0.26 10.72 +/- 0.33 9.79 +/- 0.32 9.77 +/- 0.43 10.14 +/- 0.79 I1I 7.19 +/- 0.26 7.15 +/- 0.32 6.65 +/- 0.29 7.02 +/- 0.25 7.00 +/- 0.43 12-C 7.34 +/- 0.29 7.75 +/- 0.17 7.03 +/- 0.33 7.47 +/- 0.30 7.40 +/- 0.52 13-C 10.57 +/- 0.29 10.53 +/- 0.27 10. 14 +/- 0.35 9.96 +/- 0.38 10.30:L 0.52 14-C 9.84 +/- 0.44 10.27 +/- 0.47 9.39 +/- 0.48 10.09 +/- 0.33 9.90 +/- 0.66 15-C 7.89 +/- 0.28 8.24 +/- 0.27 7.82 +/- 0.31 7.89 +/- 0.20 7.96 +/- 0.33 16-C A 6.72 +/- 0.26 6.04 +/- 0.30 5.94 +/- 0.23 6.23 +/- 0.69 27 8.97 +/- 0.53 8.94 +/- 0.37 8.45 +/- 0.38 8.80 +/- 0.22 8.79 +/- 0.41 41 6.82 +/- 0.36 6.79 +/- 0.21 6.79 +/- 0.59 6.82 +/- 0.29 6.81 +/- 0.03 42 7.99 +/- 0.27 8.05 +/- 0.31 7.82 +/- 0.47 7.71 +/- 0.19 7.89 +/- 0.27 43 6.85 +/- 0.23 7.16 +/- 0.27 6.34 +/- 0.29 6.93 +/- 0.22 6.82 +/- 0.60 44 8.24 +/- 0.29 8.21 +/- 0.49 8.13 +/- 0.52 8.81 +/- 0.39 8.35 +/- 0.54 45 7.08 +/- 0.23 7.37 +/- 0.19 7.16 +/- 0.28 7.63 +/- 0.32 7.31 +/- 0.43 46 8.01 +/- 0.28 8.71 +/- 0.35 7.29 +/- 0.38 8.15 +/- 0.26 8.04 +/- 1.01 47 7.73 +/- 0.31 7.74 +/- 0.47 7.43 +/- 0.27 7.79 +/- 0.38 7.67 +/- 0.28 48 9.68 +/- 0.27 9.65 +/- 0.25 9,56 +/- 0.30 9.33 +/- 0.41 9.56 +/- 0.27 49 7.18 +/- 0.22 7.29 +/- 0.28 6.77 +/- 0.23 6.96 +/- 0.20 7.05 +/- 0.40 50 7.91 +/- 0.23 8.01 +/- 0.28 7.52 +/- 0.29 7.59 +/- 0.26 7.76 +/- 0.41 51 6.52 +/- 0.17 6.42 +/- 0.28 6.45 +/- 0.41 6.22 +/- 0.18 6.40 +/- 0.22 52 7.22 +/- 0.18 7.21 +/- 0.16 6.96 +/- 0.48 7.22 +/- 0.30 7.15 +/- 0.22 53 7.79 +/- 0.17 7.79 +/- 0.28 7.27 +/- 0.46 7.50 +/- 0.25 7.59 +/- 0.44 55 7.83 +/- 0.58 9.97 +/- 1.04 7.53 +/- 0.36 7.66 +/- 0.27 8.25 +/- 2.00 56 6.86 +/- 0.42 6.88 +/- 0.24 6.39 +/- 0.22 6.55 +/- 0.30 6.67 +/- 0.42 57 7.43 +/- 0.36 7.75 +/- 0.28 7.25 +/- 0.37 7.22 +/- 0.23 7.41 +/- 0.42 59 8.02 +/- 0.25 8.22 +/- 0.26 7.91 +/- 0.26 7.85 +/- 0.27 8.00 +/- 0.28 60 6.94 +/- 0.18 7.09 +/- 0.27 7.00 +/- 0.36 6.68 +/- 0.20 6.93 +/- 0.31 61 7.34 +/- 0.25 7.69 +/- 0.23 7.34 +/- 0.35 7.56 +/- 0.20 7.48 +/- 0.30 62 8.50 +/-0.18 8.83 +/- 0.21 7.95 +/- 0.27 8.06 +/- 0.31 8.34 +/- 0.70 63 8.79 +/- 0.31 9.29 +/- 0.24 8.63 +/- 0.29 8.54 +/- 0.33 8.81 +/- 0.58 64 7.57 +/- 0. 18 7.66 +/- 0.16 6.96 +/- 0.30 7.50 +/- 0.26 7.42 +/- 0.55 65 8.00 +/- 0.26 8.10 +/- 0.23 7.54 +/- 0.33 7.76 +/- 0.25 7.85 +/- 0.43 66-X 7.11 +/- 0.16 7.20 +/- 0.23 6.82 +/- 0.23 6.94 +/- 0.40 7.02 +/- 0.29 73-X 9.75 +/- 0.60 9.55 +/- 0.27 9.15 +/- 0.42 9.34 +/- 0.24 9.45 +/- 0.45

Dominihn Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstome Station 2006 Table 1, Quarterly TLD Gamma Exposure Rate (uR/hr) Page 2 of 2 Location First Second Third Fourth Average Nuimber Quarter Quarter Quarter Quarter A 2 s.d.

74-X 7.41 +/- 0.33 7.93 +/- 0.19 7.54 +/- 0.25 7.57 +/- 0.19 7.61 +/- 0.39 75-X 7.20 +/- 0.17 7.28 +/- 0.28 6.68 +/- 0.22 6.55 +/- 0.34 6.93 +/- 0.63

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 2, Air Particulate Gross Beta Radioactivity (le-3 pCi/m3) Page I of 4 Collection Locations Date JANUARY 01 02 03 04 10 11 12/26 - 01/01 14.4 +/- 4.0 12.3 +/- 4.1 15.0 +/- 3.7 13.3 +/- 3.6 12.8 +/- 3.8 14.7 +/- 4.3 01/02 - 01/08 16.9 +/-4.0 17.7 +/-4.1 15.3 +/- 3.6 13.9 +/- 3.5 17.8 +/-3.8 13.8 +/-4.1 01/09 -01/15 13.1 +/- 3.8 15.7 +/-4.0 14.4 +/-3.6 17.8 +/-3.7 13.3 +/-3.6 16.0 +/-4.2 01/16 -01/22 14.3 +/-3.8 16.4 +/-4.0 12.1 +/-3.5 15.7 +/-3.6 17.6 +/-3.8 14.7 +/-4.1 01/23 -01/29 16.4 +/-4.0 16.1 +/-4.1 19.3 +/-3.9 16.7 +/-3.7 16.9 +/-3.9 18.6 +/-4.4 FEBRUARY 01 02 03 04 10 11 01/30 -02/05 15.4 +/-3.9 12.8 +/-3.9 16.4 +/-3.7 14.5 +/-3.5 14.9 +/-3.8 13.6 +/-4.2 02/06 -02/12 15.1 +/-4.1 13.0 +/-4.1 14.7 +/-3.8 12.9 +/-3.6 16.6 +/-4.0 14.4 +/-4.4 02/13 -02/19 23.9 +/-4.5 26.9 +/-4.7 24.2 +/-4.2 21.2 +/-4.0 25.2 +/-4.4 25.4 +/-4.9 02/20 - 02/26 28.9 +/- 4.7 31.4 +/- 4.8 28.5 +/- 4.3 29.5 +/- 3.9 29.4 +/- 4.4 28.4 +/- 4.9 MARCH 01 02 03 04 10 11 02/27 - 03/05 19.5 +/- 4.1 18.7 +/- 4.2 19.6 +/- 3.8 16.7 +/- 3.5 17.9 +/- 3.9 22.2 +/- 4.5 03/06 -03/12 11.2 +/-4.0 12.2 +/-4.2 17.0 +/-3.9 15.7 +/-3.6 16.3 +/-4.0 15.6 +/-4.6 03/13 - 03/19 14.5 +/- 4.2 14.6 +/- 4.2 16.6 +/- 3.9 18.6 +/- 3.7 15.6 +/- 4.0 14.8 +/- 4.6 03/20 -03/26 10.2 +/-3.6 11.0 +/-3.7 12.4 +/-3.4 11.9 +/-3.2 9.1 +/- 3.0 11.1 +/- 3.1 QtrAvg:L2 sd 16.4 +/-9.8 16.8 +/-11.5 17.3 +/-8.9 16.8 +/-8.8 17.2 +/- 10.0 17.2 +/-9.8 JANUARY 15-C 27 12/26 -01/01 12.0 +/-3.6 12.3 +/-4.2 01/02 -01/08 20.1 +/-3.9 14.0 +/-4.1 01/09 -01/15 15.5 +/-3.6 17.6 +/-4.2 01/16 -01/22 13.0 +/-3.6 14.2 +/-4.1 01/23 -01/29 13.8 +/-3.6 20.3 +/-4.4 FEBRUARY 15-C 27 01/30 -02/05 15.7 +/-3.7 14.0 +/-3.8 02/06 -02/12 10.1 +/- 3.7 14.4 +/-3.9 02/13 -02/19 22.4 +/-4.2 23.4 +/-4.3 02/20 -02/26 31.1 +/-4.4 27.4 +/- 4.4 MARCH 15-C 27 02/27 -03/05 15.4 +/-3.6 16.4 +/-3.9 03/06 -03/12 14.6 +/-3.9 18.6 +/-4.3 03/13 -03/19 14.6 +/-3.9 12.7 +/-4.0 03/20 -03/26 11.0 +/-3.4 11.2 +/-3.6 Qtr Avg-+2 sd 16.1 +/- 10.81679. 16.7 +/- 9.1

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 2, Air Particulate Gross Beta Radioactivity (le-3 pCi/m3) Page 2 of 4 Collection Locations Date APRIL 01 02 03 04 10 11 03/27 - 04/02 25.2 +/- 4.7 23.5 +/- 4.5 21.6 +/- 4.0 25.9 +/- 4.1 26.5 +/- 3.9 25.6 +/- 4.1 04/03 - 04/09 15.9 +/-4.0 16.6 +/- 4.1 19.8 +/- 3.8 15.7 +/- 3.4 15.0 +/- 3.3 18.1 +/-3.3 04/10 - 04/16 17.6 +/-4.4 11.7 +/-4.0 14.1 +/-3.7 15.7 +/- 3.6 11.2 +/- 3.5 15.2 +/- 3.4 04/17 - 04/23 11.5 +/-4.0 8.7+/- 3.8 7.8+/- 3.3 11.3 +/- 3.3 8.9 +/-3.4 9.2-+3.1 04/24 - 04/30 12.3 +/-3.6 14.8 +/-3.7 14.5 +/-3.8 15.1 +/- 3.7 14.8 +/-3.8 11.0 +/-3.4 MAY 01 02 03 04 10 05/01 - 05/07 15.0+ 3.5 10.7 +/-3.2 14.4 +/-3.5 13.6 +/-3.4 14.0 +/-3.5 13.3 +/-3.3 05/08 - 05/14 5.7 3.2 4.1 +/-2.9 5.0 +/-3.2 4.5 +/-3.0 5.6 +/-3.2 5.5 +/-3.1 05115 -05/21 10.8 +/-3.3 8.8+ 3.1 10.5 +/-3.4 10.1+/-3.2 13.2 +/-3.5 9.4+/- 3.2 05/22 - 05/28 23.9 +/-3.4 19.9 3.1 22.8 +/-3.3 22.2 +/-3.2 17.2 +/-4.4 C 23.0 +/-3.3 JUNE 01 02 03 04 10 05/29 - 06/04 13.2 +/-3.9 26.5 +/-8.9 D 14.7+/- 3.9 13.9 +/-3.6 13.9 +/-3.7 11.5 +/-3.6 06/05 - 06/11I 5.8 3.2 8.5 +/-4.2 E 7.5 +/-3.2 4.6 +/-2.9 5.3 +/-3.1 6.8 +/-3.2 06/12 - 06/18 17.9 +/-4.0 19.1+/-3.8 14.0 +/-3.7 20.5 +/-3.8 20.2 +/-4.0 19.5 +/-4.0 06/19 - 06/25 13.4 +/-3.7 17.1+/-3.7 12.4 +/-3.5 16.1 +/-3.5 17.7+/- 3.8 16.0 +/-3.8 QtrAvg-+2 sd 14.5 +/- 11.2 15.5+/- 11.5 13.8+/-10.3 14.6 +/-11,9 14.1 +/-11.1 14.2+/- 11.8 APRIL 27 15-C 03/27 - 04/02 25.1 +/- 4.3 24.7 +/- 4.5 04/03 - 04/0 9 15.6 +/-3.7 18.6 +/- 4.0 04/10 - 04/16 15.1 +/-3.9 14.4 +/- 4.0 04/17 - 04/23 13.4 +/- 3.7 10.7 +/- 3.8 04/24 - 04/30 17.5 +/- 4.1 11.4 +/- 6.0 B MAY 27 15-C 05101 - 05/07 11.4 +/-3.5 13.2 +/-3.4 05/08 - 05/14 7.6+/- 3.4 4.1+/-3.0 05/15 - 05/21 14.0 +/-3.7 8.7 +/-3.2 05/22 - 05/28 20.2 +/-3.4 21.9+/- 3.3 JUNE 15-C 27 05/29 - 06/04 14.6 +/-4.0 10.3 +/-3.5 06105 - 06/11 6.11+/-3.3 5.6 +/-3.0 06/12 - 06/18 24.8 +/-4.3 18.5 +/-3.8 06/19 - 06/25 19.5 +/-4.0 15.2 +/-3.6 Qtr Avg-+2 sd 15.8+/- 11.0 14.4+/- 10.8

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 2, Air Particulate Gross Beta Radioactivity (le-3 pCi/m3) Page 3 of 4 Collection Locations Date JULY 01 02 03 04 10 11 06/26 - 07/02 22.9 +/- 5.3 22.9 +/- 5.0 23.1 +/- 5.1 22.2 +/- 4.8 22.9 +/- 5.0 23.9 +/- 5.3 07/03 - 07/09 19.0+/-4.5 15.5 +/- 4.0 20.5 +/- 4.3 17.4 +/- 4.0 21.2 +/- 4.4 22.8 +/- 4.6 07/10 - 07/16 21.1 +/- 4.1 19.4 +/- 3.9 21.0 +/- 3.9 20.2 +/- 3.6 19.3 +/- 3.9 22.1 +/- 4.1 07/17 - 07/23 17.2+/-4.1 15.6 +/- 4.6 F 18.9 +/- 3.9 18.5 +/- 3.6 21.1 +/- 4.0 19.7 +/- 4.1 07/24 - 07/30 25.1 +/- 4.4 22.6 +/- 3.9 22.9 +/- 4.2 24.4 +/- 3.9 21.2 +/- 4.2 28.9 +/- 4.7 AUGUST 01 02 04 10 11 03 07/31 - 08/06 27.5 +/- 4.8 18.0 +/- 4.0 27.5 +/- 4.5 31.7 +/- 4.4 27.5 +/- 4.4 24.6 +/- 4.1 08/07 - 08/13 21.5 +/- 4.5 19.1 +/--3.9 21.1 +/- 4.1 23.4 +/- 4.1 21.5 +/- 4.1 23.0 +/- 4.0 08/14 - 08/20 19.9 +/- 4.5 17.0 +/- 3.9 19.5 +/- 4.1 19.7-+/- 4.0 18.9 +/- 4.0 18.0 +/- 3.9 08/21 - 08/27 21.9 +/- 3.8 19.0 +/- 3.8 20.4 +/- 3.9 22.3 +/- 3.9 21.4 +/- 3.9 20.0 +/- 3.7 SEPTEMBER 01 02 03 04 10 11 08/28 - 09/03 10.1 +/- 3.2 6.5 - 3.2 10.6 +/- 3.5 8.8 - 3.2 7.9+/- 3.3 8.8 - 3.2 09/04 - 09/10 20.3 +/- 3.9 19.9 +/-4.1 21.4 +/- 4.2 20.8+/- 4.0 21.1+/-4.1 19.3 - 3.9 09/11 - 09/17 18.4 +/- 3.0 16.3 - 4.2 F 17.1 +/--3.2 19.4.4 3.0 16.8 +/- 2.9 15.9 +/- 3.0 09/18 - 09/24 19.8 +/- 4.4 17.1 +/-4.4 21.8 +/- 4.8 18.4 +/- 4.2 19.5 +/- 4.6 22.9 +/- 4.6 Qtr Avg =1:2 sd 20.4 +/- 8.0 17.6 - 7.8 20.4 +/- 7.4 20.6 9.8 20.0 +/- 8.5 20.8 +/- 9.4 JULY 15-C 27 06/26 - 07/02 21.7 +/- 5.3 22.0 +/- 4.9 07/03 - 07/09 17.3 +/- 4.4 20.0 +/- 4.2 07/10 - 07/16 21.0 +/- 4.0 16.2 +/- 3.6 07/17 - 07/23 19.2 +/- 4.1 20.1 +/--3.9 07/24 - 07/30 25.3 +/- 4.5 21.0 +/- 3.9 AUGUST 15-C 27 07/31 - 08/06 24.8 +/- 4.6 26.1 +/- 4.3 08/07 - 08/13 21.6 +/- 4.2 20.5 +/- 3.8 08/14 - 08/20 21.2 +/- 4.3 20.7 +/- 3.9 08/21 - 08/27 20.2 +/- 4.0 21.3 +/- 3.8 SEPTEMBER 15-C 27

  • 08/28 - 09/03 7.0 +/- 3.4 8.0 +/- 3.2 09/04 - 09/10 22.8 +/- 4.4 21.3 +/- 4.0 09/I1 - 09/17 20.2+/- 3.4 15.5 +/- 2.9 09/18 - 09/24 22.2 +/- 4.9 18.7 -44.4 Qtr Avg :: 2 sd 20.3+/- 8.7 19.3 +/- 8.2

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 2, Air Particulate Gross Beta Radioactivity (le-3 pCi/m3) Page 4 of 4 Collection Locations Date OCTOBER 01 02 03 04 10 11 09/25 - 10/01 12.1 +/-3.6 14.6 +/- 3.8 13.5 +/- 3.9 18.3 +/- 3.8 17.2 +/- 4.0 19.7 +/- 4.0 10/02 - 10/08 19.8 +/- 3.7 18.1 +/- 3.8 20.0 +/- 4.0 21.6+/- 3.8 22.0 +/- 4.0 21.9 +/- 3.9 10/09- 10/15 24.0 +/- 5.6 17.8 +/- 5.3 25.8 +/- 6.0 23.0 +/- 5.4 23.5 +/- 5.9 23.3 +/- 5.7 10/16- 10/22 18.2 +/- 3.9 20.4 +/- 4.1 18.1 +/-4.0 21.4 +/- 3.9 18.9 +/- 4.0 21.8 +/-4.1 10/23 - 10/29 8.0+/-3.2 9.3 +/- 3.2 7.0 +/- 3.1 11.4 +/- 3.3 10.8 +/- 3.6 10.5 +/- 3.5 NOVEMBER 01 02 03 04 10 11 10/30 - 11/05 26.6+/-4.1 26.0 +/- 4.1 27.9 +/- 4.1 26.2 +/- 4.0 28.8 +/- 4.4 28.0 +/- 4.3 11/06 - 11/12 15.0 +/- 3.7 16.2 +/- 3.7 18.2 +/- 3.9 18.5 +/- 3.7 20.5 +/- 4.3 17.1 +/- 4.0 11/13 - 1 1/19 9.1+/- 3.4 10.3 +/-3.1 8.6 +/- 3.2 9.1 +/- 3.2 11.4 +/- 3.7 11.5 +/- 3.6 11/20 - 11/26 21.0 +/- 3.9 16.6 +/- 3.4 22.0 +/- 3.9 22.5 3.8 21.3 +/- 4.2 18.9 +/- 4.0 DECEMBER 01 02 03 04 10 11 11/27 - 12/03 27.8 +/- 4.0 25.2 +/- 3.6 25.5 +/- 3.9 29.8 +/- 3.9 23.4 +/- 4.1 22.3 +/- 4.0 12/04 - 12/10 33.8 +/- 4.4 34.5 +/- 4.1 31.0 +/- 4.2 33.3 +/- 4.9 33.2 +/- 4.7 33.8 +/- 4.5 12/1l - 12/17 31.8 +/- 4.3 25.8 +/- 3.8 28.3 +/- 4.1 28.5 +/- 4.8 23.8 +/- 4.3 28.1 +/- 4.4 12/18- 12/24 18.1 +/- 3.9 18.9 +/- 3.5 17.3 +/- 3.8 19.5 +/- 4.5 18.3 +/- 3.8 16.5 +/- 3.9 12/25 - 12/31 18.5 +/- 3.8 14.6 +/- 3.2 15.5 +/- 3.6 13.6 +/- 4.1 18.6 +/- 3.6 20.5 +/- 4.0 Qtr Avg

  • 2 sd 20.3 +/- 15.2 19.2+/- 13.1 19.9+/- 14.1 21.2 +/- 13.3 20.8 +/- 11.4 21.0 +/- 12.1 Ann Avg + 2 sd 17.9+/- 12.5 17.3 +/- 11.5 17.9+/- 11.8 18.3 +/- 12.4 18.1 +/- 11.6 18.3 +/- 12.2 OCTOBER 15-C 27 09/25 - 10/01 16.7+/- 4.1 15.4 +/- 3.7 10/02 - 10/08 23.6 +/- 4.2 22.1 +/- 3.8 10/09- 10/15 22.4 +/- 5.9 22.2 +/- 5.4 10/16- 10/22 23.8 +/- 4.4 18.4 +/- 3.8 10/23 - 10/29 10.7-+/- 3.7 7.7 +/- 3.1 NOVEMBER 15-C 27 10/30 - 11/05 28.4 +/- 4.6 29.4 +/- 4.2 11/06- 11/12 16.2 +/- 4.3 14.6 +/- 3.8 11/13 - 11/19 10.5 +/- 3.7 11.7 +/- 3.4 11/20 - 11/26 23.4 +/- 4.4 20.8 +/- 3.9 DECEMBER 15-C 27 11/27 - 12/03 24.4 +/- 4.3 27.8 +/- 4.1 12/04 - 12/10 33.5 +/- 4.8 31.9 +/- 4.3 12/11 - 12/17 28.9 +/- 4.7 25.5 +/- 4.1 12/18- 12/24 13.9+/-4.1 20.8 +/- 4.0 12/25 - 12/31 16.9 +/- 4.1 14.5 +/- 3.6 Qtr Avg + 2 sd 21.0+/- 13.4 20.2 +/- 13.5 Ann Avg
  • 2 sd 18.3 +/- 12.1 17.8 +/- 11.6

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 3, Airborne Iodine 1-131 (le-3 pCi/m3) Page 1 of 4 Collection Locations Date JANUARY 01 02 03 04 10 11 12/26 - 01/01 6+/-15 1 +/--23 0+/-21 -2+/- 16 0+/- 18 13+/- 19 01/02 - 01/08 -5 +/- 17 0+/--16 10+/- 16 8-+/--16 5+/- 15 -2 20 01/09 - 01/15 0+/- 15 -12+/- 16 -3+/- 16 -1 +/- 15 3 +/- 15 -2+/- 17 01/16 - 01/22 +/- 19 -13+/- 18 7 +/- 14 2+/-16 12 +/- 16 14+/- 20 01/23 - 01/29 15+/- 20 -16+/- 17 -32+/- 18 8 14 13 +/- 22 4-21 FEBRUARY 01 02 03 04 10 11 01/30 - 02/05 2+/-29 4 +/-23 -4 +/-24 22 +/- 26 8+/--23 -2+/-31 02/06 - 02/12 4+/-16 0+/-20 15 +/- 17 -6+/- 16 3 +/- 15 2+/-20 02/13 - 02/19 -14:-27 -5 +/- 21 25 6+/--24 -9 +/- 25 6+/- 23 02/20 - 02/26 13 +/--22 2+/-21 9+/- 24 22 +/- 23 2+/--28 14+/- 28 MARCH 01 02 03 04 10 11 02/27 - 03/05 -31 +/--22 10+/- 21 13 +/-20 -3+/- 14 -19 17 3 +/- 22 03/06 - 03/12 14 +/- 20 2+/-16 -8+/- 16 -4+/- 13 -2 17 2+/- 19 03/13 - 03/19 2+/-29 11 +/-24 14 +/- 25 18+/- 26 -17+/- 21 5+/--25 03/20 - 03/26 6+/--24 -7+/- 24 -8 +/- 24 -2 +/- 20 -27 +/- 23 20 +/- 23 JANUARY 15-C 27 12/26 - 01/01 -1 +/- 21 0+/-21 01/02 - 01/08 -5 +/- 18 6+/- 20 01/09 - 01/15 -11 +/- 18 9+/-18 01/16 - 01/22 10+/- 19 -7.+/- 19 01/23 - 01/29 1 +/- 16 5+/-19 FEBRUARY 15-C 27 01/30 - 02/05 -2 +/- 22 10+/- 23 02/06 - 02/12 -5 +/- 20 3 20 02/13 - 02/19 7+/--27 -18 +/- 22 02/20 - 02/26 -11 +/- 23 -7+/- 26 MARCH 15-C 27 02/27 - 03/05 4+/- 20 -6+/- 16 03/06 - 03/12 -10 +/- 16 12+/- 21 03/13 - 03/19 7+/-27 -3 +/- 23 03/20 - 03/26 2+/-27 -11+/- 22

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 3, Airborne Iodine 1-131 (le-3 pCi/m3) Page 2 of 4 Collection Locations Date APRIL 01 02 03 04 10 11 03/27 - 04/02 4 +/-20 9+/-21 17 19 -17 +/-19 -7+/- 17 6+/-17 04/03 - 04/09 16+/- 17 7 +/- 17 6 17 12+/- 15 -18+/- 14 -6 +/-14 04/10 - 04/16 -10 +/-23 -18,+/- 20 -18+/-20 -11 +/- 17 -21 +/- 19 1 +/- 19 04/17 - 04/23 2 +/- 24 -12+/- 23 -4 +/- 22 5 +/- 17 -3 23 7+/-20 04/24 - 04/30 0+/--15 0+/-15 1 +/-18 2 +/-,15 15+/- 15 -2 +/- 20 MAY 01 02 03 04 10 11 05/01 - 05/07 2-15 6 +/- 14 -5 +/- 16 -5 +/- 15 5+/--14 0+/-16 05/08 - 05/14 10 18 9 +/- 21 4 +/- 21 5 +/- 20 -13 +/- 21 7+/- 18 05/15 - 05/21 11 -15 -13 +/- 15 10+/- 19 -7+/- 19 -1 +/- 17 7 +/-,15 05/22 - 05/28 -10 +/- 22 2 +/--20 8+/-22 1+/- 17 -5 +/- 19 C 5 +/- 19 JUNE 01 02 03 04 10 11 05/29 - 06/04 -14+/-27 15+/-37 D 0 +/--22 -7 +/- 22 -3 +/- 26 -33 +/- 22 06/05 - 06/11 -7 +/- 22 6+/-22 E 9 +/-,18 -6 +/- 20 -1+/-+/-20 2 +/-,21 06/12 - 06/18 -1 +/- 26 4 +/--25 -17 +/- 22 28 +/- 25 14+/- 25 -24 +/- 27 06/19 - 06/25 26 +/- 27 -37 +/- 27 2+/--26 -11i+/- 21 0+/-21 -12 +/- 25 APRIL 15-C 27 03/27 - 04/02 -22 16 10 +/- 19 04/03 - 04/09 7 +/- 15 15 +/- 20 04/10 - 04/16 6 +/- 16 -24 +/- 17 04/17 - 04/23 -2 24 2 +/- 24 04/24 - 04/30 -14 18 -16 +/- 19 B MAY 15-C 27 05/01 - 05/07 -10 +/- 21 8+/--22 05/08 - 05/14 0 +/- 23 5 +/-,19 05/15 - 05/21 8 +/- 18 -11 +/- 18 05/22 - 05/28 -12 +/- 19 -5 +/- 22 JUNE 15-C 27 05/29 - 06/04 24+/- 29 17,+/- 33 06/05 - 06/11 -12 +/- 19 11 +/- 20 06/12 - 06/18 -2 19 6 +/--25 06/19 - 06/25 24 - 28 -1 +/- 31

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 3, Airborne Iodine 1-131 (le-3 pCi/m3) Page 3 of 4 Collection Locations Date JULY 01 02 03 04 10 11 06/26 - 07/02 -2+/- 14 -12+/- 15 3+/-11 1 +/- 15 -2+/- 16 -3 +/- 16 07/03 - 07/09 -11 4-22 7 +/-23 13+/- 21 8 +/- 17 7+/-21 1 +/- 19 07/10 - 07/16 -24 18 9 +/-18 -11 +/- 19 -3 +/- 17 -9 +/- 19 -II +/- 20 07/17 - 07/23 -6 28 -5 +/- 29 F 5+/-27 0+/--25 6 +/- 24 0+/--29 07/24 - 07/30 -5 16 -6 +/- 14 16 -6 +/- 12 0+/- 15 2+/--17 AUGUST 01 02 03 04 10 11 07/31 - 08/06 4-+/--22 3 +/- 20 22 +/- 22 -6 +/- 23 -5 +/- 18 -16+/- 19 08/07 - 08/13 24+/--23 5 +/- 25 -5+/- 19 -5 +/- 19 -8 + 23 -11 +/- 18 08/14 - 08/20 14+/--26 -4 +/- 21 F -4+/- 22 1 +/- 19 -2+/- 22 9 +/- 20 08/21 - 08/27 -20 +/- 20 10+/- 22 13 +/- 18 +/-21 12 14 2+/--13 SEPTEMBER 01 02 03 04 10 11 08/28 - 09/03 -6+/- 17 4 +/-22 15 +/-20 -3 +/- 15 2 +/-20 2 +/-19 09/04 - 09/10 -6 +/- 18 9+/--18 6 19 -17 16 9+/--18 -6+/- 19 09/11 - 09/17 12+21 -8 +/- 21 5 21 -4 23 -11 +/-19 0 +/- 26 09/18 - 09/24 8+/-19 -5 +/- 19 20 +/- 18 -13 15 -2 17 -2+/- 19 JULY 15-C 27 06/26 - 07/02 10 17 -9+/- 17 07/03 - 07/09 -6 19 18+/- 21 07/10 - 07/16 -7 19 5+/-19 07/17 - 07/23 2 +/- 27 10+/- 27 07/24 - 07/30 0+/-18 -13 18 AUGUST 15-C 27 07/31 - 08/06 1 +/-21 -2 +/- 21 08/07 - 08/13 12 22 -1+/- 19 08/14 - 08/20 -5 19 6+/-16 08/21 - 08/27 -8 17 5+/--16 SEPTEMBER 15-C 27 08/28 - 09/03 9+/- 19 7+/--18 09/04 - 09/10 5 +/- 20 6+/--18 09/11 - 09/17 10 +/- 29 12 +/- 22 09/18 - 09/24 13+/-- 19 21 +/- 21

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 3, Airborne Iodine 1-131 (le-3 pCi/m3) Page 4 of 4 Collection Locations Date OCTOBER 01 02 03 04 10 11 09/25 - 10/01 -9 +/- 22 2+/- 24 17+/- 27 -13.+/- 24 0+/- 22 5 +/- 22 10/02- 10/08 -3 +/-15 0.+/- 15 -10+/- 16 -6+/- 19 -9+/- 15 -3 +/- 14 10/09- 10/15 -2+/- 19 20 +/- 23 -5 +/- 24 14 +/- 22 8 +/-26 13 +/- 26 10/16- 10/22 2+/-19 -7+/- 19 -14 +/- 24 10-+/- 20 7 +/-20 2 +/- 23 10/23 - 10/29 -14+/-21 -8.+/- 16 4+/-16 -12 +/-16 -11 +/- 28 0-+/- 23 NOVEMBER 01 02 03 04 10 11 10/30 - 11/05 -13 +/-18 -7.+/- 24 -4 +/- 22 2-+/- 23 2+/-26 0 +/- 24 11/06 - 11/12 15 +/- 20 6+/-20 2 +/-24 -8 +/- 21 2+/-25 -20 +/- 24 11/13 - 11/19 2+/- 22 -19.+/- 19 13 +/- 22 0 +/- 20 5 +/- 23 -16 +/- 23 11/20 - 11/26 4+/- 23 4.+/- 17 -10 +/- 23 18+/-20 -16+/- 25 -20 +/- 23 DECEMBER 01 02 03 04 10 11 11/27 - 12/03 2+/-16 9+/--14 -3 +/- 15 3+/-15 -2+/- 18 2+/-18 12/04- 12/10 3+/-16 -1 +/- 12 -7+/- 15 -9+/- 16 -7 +/- 20 +/- 15 12/11 - 12/17 -8 +/- 28 -1+/- 18 -8 +/- 26 7+/-25 5 +/- 26 -9 +/- 23 12/18 - 12/24 -3 +/- 25 5 +/- 27 -3 +/- 26 -19+/- 32 -18 +/- 25 0+/-28 12/25- 12/31 -8 +/- 20 -9 +/- 20 10+/- 21 -5 +/- 25 14+/- 22 2+/-18 OCTOBER 15-C 27 09/25 - 10/01 -8 +/- 21 -5 +/- 26 10/02 - 10/08 4+/- 17 -5 +/- 12 10/09- 10/15 -19+/- 27 7+/-24 10/16- 10/22 -3 27 2+/-22 10/23 - 10/29 2+/- 23 12+/- 20 NOVEMBER 15-C 27 10/30 - 11/05 -3 +/- 22 7-+/--21 11/06 - 11/12 3 +/- 26 -4 +/- 25 11/13 - 1 1/19 -7 +/- 23 -13+/- 21 11/20 - 11/26 2+/-25 9-+/--23 DECEMBER 15-C 27 11/27 - 12/03 10 19 10+/- 19 12/04 - 12/10 -3 17 0+/- 13 12/11 - 12/17 21 -2+/- 19 12/18 - 12/24 -12 +/-20 -11 +/-18 12/25- 12/31 -5+/- 19 -4 21

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 4-A, Air Particulates Gamma Spectra - Quarter 1 (le-3 pCi/m3) Page 1 of I Location Isotope Ba-140 Be-7 Ce-141 Ce-144 Co-58 Co-60 Cr-51 01 -10.0 15.0 91.0 +/- 28.0 0.4 +/- 2.2 -0.6 +/- 3.2 0.3 +/- 1.2 -0.2 +/- 0.8 -2.0 +/- 23.0 02 0.0 16.0 107.0 +/- 29.0 -0.4+/- 1.5 -0.3 +/- 2.1 0.2 +/- 0.9 0.9 +/- 0.8 -7.0+/- 17.0 03 -4.0 16.0 96.0 +/- 25.0 0.8 +/- 2.1 -2.1 +/-2.3 0.5 +/- 1.0 0.5 +/- 0.6 15.0 17.0 04 11.0+ 11.0 107.0 +/- 23.0 -1.9+/- 1.6 -0.2 +/- 2.3 -1.1 +/-1.1 0.4 +/- 0.8 -3.0+/- 14.0 10 0.0+/- 11.0 107.0 28.0 -1.1 +/- 2.1 0.9 +/- 3.1 0.4 1.3 -0.4+/- 1.4 10.0 +/- 24.0 11 -6.0 13.0 87.0 +/- 27.0 0.4 +/- 2.1 -2.3 +/- 3.0 0.1 1.1 0.4+/- 1.0 -20.0 +/- 23.0 15-C -7.0 10.0 77.0 + 24.0 -0.4 +/- 2.0 -0.9 +/- 2.3 1.8 1.4 -1.0 +/- 0.9 -6.0 +/- 24.0 27 14.0 +/- 20.0 84.0 + 29.0 -1.1 +/- 2.5 -0.8 +/- 3.5 -0.2 +/-1.7 0.6+/- 1.3 6.0 18.0 Cs-134 Cs-137 Mn-54 Nb-95 Ru-103 Ru-106 Zr-95 01 0.5 +/- 0.9 0.7 +/- 0.8 0.3 +/- 0.7 1.2+/- 1.9 0.7 +/- 2.0 -0.7 +/- 6.2 -1.0+/- 1.6 02 -0.1 +/- 0.7 0.5 +/- 0.5 0.2+/- 0.9 -0.4+/- 1.8 0.0+/- 1.3 4.4 +/- 6.3 -2.6 +/- 2.6 03 -0.2 +/- 0.6 -0.1 +/-0.6 -0.6+/- 1.0 -1.2+/- 1.6 0.7+/- 1.2 1.3 +/- 6.8 2.5 +/- 2.8 04 0.8 +/- 0.7 0.0 +/- 0.5 0.0+/- 0.5 -1.5 +/- 2.0 0.7+/- 1.3 -0.6 +/- 4.6 -0.8+/- 1.9 10 -0.8 +/- 0.9 0.0 +/- 0.7 0.2+/- 1.0 0.7+/- 1.8 -0.5+/- 1.5 2.4 +/- 8.2 1.7+/- 2.3 11 -0.2 +/- 0.6 0.2 +/- 0.7 0.4 +/- 0.8 0.3 +/- 2.6 0.7+/- 1.0 -6.0 10.0 0.3 +/- 2.5 15-C 0.3 +/- 0.7 -0.1 +/- 0.8 0.1 +/- 0.6 -1.6+/- 1.7 -0.7+/- 1.1 -3.9 +/-6.0 -0.1 +/- 2.2 27 0.7 +/- 0.7 -0.1 +/- 0.9 0.5 +/- 0.8 0.2 +/- 2.2 0.3 +/- 2.0 -3.8 8.4 -1.2 +/- 2.2

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 4-B, Air Particulates Gamma Spectra - Quarter 2 (le-3 pCi/m3) Page I of I Location Isotope Ba-140 Be-7 Ce-141 Ce-144 Co-58 Co-60 Cr-51 01 9.0 +/- 22.0 80.0 +/- 36.0 -0.5 +/- 3.9 -0.4 +/- 5.8 -0.3 +/- 2.0 -0.3 +/- 0.9 -22.0 +/- 36.0 02 5.0+/- 16.0 95.0 +/- 37.0 1.7+/-4.5 6.1 +/- 5.7 1.6+/- 1.9 -0.1 +/- 1.5 30.0 +/- 33.0 03 -4.0 +/- 26.0 98.0 +/- 37.0 0.1+/-4.1 -4.3 +/- 5.7 0.6+/- 1.5 0.6+/- 1.0 -18.0+/- 31.0 04 -8.0 : 20.0 69.0 +/- 33.0 -0.1 +/-3.6 -1.1 +/- 5.4 0.4+/-1.6 0.5 +/- 1.3 -20.0 +/- 30.0 10 -13.0+/-: 15.0 90.0 +/- 34.0 1.6+/-4.7 0.4 +/- 5.5 0.2+/- 1.8 -0.3 +/- 0.8 3.0+38.0 II -16.0+/-:L 20.0 97.0+/- 34.0 -1.2 +/- 3.9 1.5 +/- 4.2 -1.1 +/- 1.2 1.2+/- 1.3 -11.0+/-32.0 15-C 13.0 : 20.0 79.0 +/- 31.0 0.4+/-4.2 -2.9 15.9 0.7+/- 1.5 -1.3 +/- 1.2 6.0 +/- 33.0 27 -4.0 +/- 15.0 139.0 +/- 39.0 1.9 +/- 3.8 -0.4+/- 5.7 -0.9+/- 1.6 0.2+/- 1.1 0.0 +/- 33.0 Cs-134 Cs-137 Mn-54 Nb-95 Ru-103 Ru-106 Zr-95 01 0.4 : 0.9 -0.1 +/- 1.0 0.0+/- 1.2 2.7 +/- 3.4 0.3 +/- 2.4 1.0+/- 12.0 -1.2 +/- 2.8 02 0.7 *- 1.3 0.1 +/-0.9 0.0+/- 1.2 -1.6+/- 3.3 0.7+/- 1.4 -3.0+/- 12.0 1.8 +/- 3.1 03 0.1 : 0.9 0.7 +/- 1.2 -0.2+/- 1.5 -2.9 +/- 2.2 -0.3 +/- 2.6 0.0+/- 10.0 -1.9 +/- 2.9 04 -0.2+/-: 1.0 -0.4+/- 1.1 -0.6+/- 1.0 -0.6+/- 2.3 -0.3 +/- 2.2 -10.0 13.0 -0.6 +/- 2.7 10 0.5*1 1.1 0.0 + 1.0 -0.2+/- 1.1 1.3 +/- 3.5 -1.6 +/- 2.6 1.0 11.0 2.0 +/- 2.3 11 0.0: -0.6 -0.3 +/- 1.0 0.3 +/- 1.2 0.3 +/- 2.6 0.0 +/- 2.1 7.0 8.0 -0.6 +/- 2.4 15-C -0.2:L 1.1 0.5 +/- 1.1 0.2+/- 1.4 -0.1 +/- 3.3 -0.3 +/- 2.4 4.5 9.9 1.7 +/- 2.6 27 0.0=: 1.1 -0.4 +/- 0.9 0.9+/- 1.3 -1.3 +/- 3.6 -0.7 +/- 3.0 -0.9 8.3 -0.2 +/- 2.8

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 4-C, Air Particulates Gamma Spectra - Quarter 3 (le-3 pCi/m3) Page 1 of I Location Isotone Location Istp Ba-140 Be-7 Ce-141 Ce-144 Co-58 Co-60 Cr-51 01 0.0 +/- 19.0 124.0 +/- 34.0 0.4+/- 3.9 -2.8 +/- 5.2 0.5 +/- 1.8 -0.4 +/- 0.9 -5.0 +/-34.0 02 -16.0 +/- 22.0 94.0+/- 30.0 1.1+/-4.1 2.2 +/- 4.6 0.2+/- 1.5 0.3 +/- 0.8 -17.0 35.0 03 0.0 + 22.0 139.0 +/- 33.0 -1.3 +/- 4.0 -2.4 +/- 4.5 1.5 +/- 1.6 0.1 +/- 0.7 16.0 30.0 04 11.0+/- 16.0 140.0 +/- 31.0 2.4 +/- 4.0 -4.0 +/- 4.4 -0.7+/- 1.4 0.1 +/- 1.0 -7.0 +/-32.0 10 8.0+21.0 128.0 +/- 33.0 -0.2+/-3.8 5.3 +/- 4.2 0.5 +/- 1.2 -0.1 +/- 1.0 -12.0 +/-32.0 11 4.0 13.0 107.0 +/- 30.0 2.2 +/- 4.3 -0.8 +/- 4.1 -0.4+/- 1.7 -0.3 +/- 1.1 25.0 +/-31.0 15-C 4.0 18.0 129.0 +/- 34.0 3.2 +/- 4.5 -2.0 +/- 4.9 0.4+/- 1.4 0.1 +/- 0.9 -3.0 +/-34.0 27 11.0+/- 19.0 134.0 +/- 31.0 -0.6 +/- 3.8 -2.0 +/- 4.1 -0.2+/- 1.4 0.0+/- 0.6 -5.0 +/-27.0 Cs-134 Cs-137 Mn-54 Nb-95 Ru-103 Ru-106 Zr-95 01 -0.1 +/- 0.8 1.0 +/- 0.8 0.2 +/- 0.9 1.4+/- 3.0 0.2 +/- 2.2 -0.5 +/- 8.6 -0.4 +/- 2.5 02 0.8 +/- 0.8 -0.4 +/- 0.7 0..5 +/- 1.1 -0.9 +/- 3.2 -0.2 +/- 2.5 4.4+/- 8.7 0.8 +/- 3.1 03 0.4 +/- 0.9 0.5 +/- 0.8 0.1 +/- 0.8 -0.5 +/- 2.1 -2.1 +/- 2.6 -2.5 +/- 8.9 4.1 +/-3.1 04 0.3 +/- 1.0 -0.5 +/- 0.9 0.2 +/- 0.7 -1.6+/- 2.1 0.4+/- 1.8 -2.9 +/- 9.7 0.0 +/- 2.4 10 -0.3 +/- 1.0 0.3 +/- 0.9 -0.2 +/- 0.9 -2.0 +/- 2.3 0.7 +/- 2.6 -1.6+/- 9.0 -0.3 +/- 2.6 11 -0.6 +/- 1.0 0.3 +/- 0.6 -0.1 +/- 1.0 -0.2+/- 3.1 3.3 +/- 2.7 3.2+/- 8.6 -2.4 +/- 2.2 15-C -0.2 +/- 1.0 0.9 +/- 1.0 0.0 +/- 0.8 -1.3 +/- 3.2 0.7 +/- 2.3 -10.7 +/-9.6 1.1 +/-2.8 27 -0.2 +/- 0.9 -0.4 +/- 0.9 -0.4+/- 1.1 0.5 +/- 3.2 -1.4+/- 1.9 -7.3 +/-9.5 2.0 +/- 3.1

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 4-D, Air Particulates Gamma Spectra - Quarter 4 (le-3 pCi/m3) Page I of I Location Isotoce Lo tion Isotope Ba-140 Be-7 Ce-141 Ce-14 Co-58 Co-60 Cr-51 01 80.0 +/- 110.0 58.0 +/- 42.0 5.2 +/- 8.5 0.4+/- 5.2 1.7 +/- 2.6 0.1 +/- 1.5 -67.0 +/- 80.0 02 20.0+/- 110.0 102.0 +/- 44.0 2.8 +/- 7.8 0.0 +/- 5.5 1.4+/- 1.9 -0.6+/- 1.4 32.0 +/- 69.0 03 -26.0 +/- 88.0 135.0 +/- 50.0 6.9+/- 8.4 -2.4+/- 6.0 0.1 +/- 1.7 0.6+/- 1.2 27.0+/- 71.0 04 80.0 +/- 130.0 42.0 +/- 45.0 1.3 +/- 7.4 -0.4+/- 5.9 -2.5 +/- 1.8 0.4+/- 1.1 -13.0+/- 63.0 10 -50.0 +/- 150.0 92.0 +/- 49.0 3.2 +/- 8.9 1.3 +/- 5.5 -1.9 +/- 2.4 -0.3 +/- 0.9 -7.0 83.0 11 -50.0 +/- 110.0 58.0 +/- 39.0 -7.5 +/- 8.7 2.5 +/- 6.4 -1.7 +/- 2.9 -1.0+/- 1.0 -56.0 93.0 15-C -30.0 +/- 100.0 94.0 +/- 49.0 3.3 +/- 9.0 -0.9 +/- 5.9 -0.8 +/- 2.9 -0.1 +/- 1.4 -61.0 80.0 27 30.0 +/- 110.0 93.0 +/- 46.0 1.3 +/- 9.1 1.2 +/- 5.0 -2.4 +/- 2.0 -0.1 +/- 1.1 40.0 +/- 65.0 Cs-134 Cs-137 Mn-54 Nb-95 Ru-103 Ru-106 Zr-95 01 0.2 +/- 0.9 0.3 +/- 0.8 -0.2+/- 1.1 -3.4 +/- 6.6 2.8 +/- 3.3 3.1+/- 9.3 -1.3 +/- 4.8 02 0.0+/- 1.1 -0.3 +/- 1.1 -0.8+/- 1.1 -5.8 +/- 5.2 -1.6 +/- 3.5 2.7 +/- 9.6 1.0 +/- 3.6 03 -0.2 +/- 1.1 -0.4 +/- 1.0 -0.2+/- 1.3 -1.1 +/- 6.1 1.7 +/- 4.8 -1.3 +/- 9.9 0.3 +/- 3.1 04 -0.3 +/- 0.8 -0.3 +/- 1.0 0.9+/- 1.2 -3.8 +/- 7.9 0.6+/- 4.3 4.6+/- 8.8 3.6+/- 4.3 10 -0.7 +/- 1.1 0.5 +/- 0.9 0.0 +/- 0.9 -4.2+/- 8.1 0.6+/- 4.6 -4.0+/- 11.0 -1.6 +/- 4.0 11 -0.1 +/- 1.0 0.6+/- 1.0 -0.2+/- 1.1 -1.9+/- 6.6 -1.7 +/- 4.5 -2.5 9.0 -0.3 +/- 3.9 15-C 0.9 +/- 1.4 -0.8 +/- 1.2 0.2+/- 1.2 1.6 +/- 7.2 -0.6 +/- 4.8 8.0+/- 13.0 0.6+/- 4.9 27 -0.2 +/- 1.2 0.3 +/- 0.9 0.2 +/- 0.8 -3.6+/- 5.7 0.0 +/- 3.5 -3.7+/- 8.2 -1.2 +/- 4.8

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 6, Soil (pCi/g Dry) Page 1 of I Location Collection Isotope Date Date 03 Be-7 Ce-141 Ce-144 Co-58 Co-60 Cr-51 05/05/06 0.06 +/- 0.30 0.00 +/- 0.05 0.10 +/- 0.20 -0.03 +/- 0.04 -0.04 +/- 0.05 -0.01 +/- 0.33 Cs-134 Cs-137 Fe-59 K-40 Mn-54 Nb-95 05/05/06 0.02 +/- 0.04 0.63 +/- 0.10 -0.01 +/- 0.08 10.90 +/- 1.50 -0.02 +/- 0.04 0.00 +/- 0.05 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 05/05/06 0.00 +/- 0.03 0.12 +/- 0.36 0.04 +/- 0.10 0.66 +/- 0.20 -0.01 +/- 0.11 -0.03 +/- 0.06 04 Be-7 Ce-141 Ce-144 Co-58 Co-60 Cr-51 05/05/06 0.27 +/- 0.31 -0.02 +/- 0.05 0.19 +/- 0.22 -0.02 +/- 0.04 0.01 +/- 0.04 0.26 +/- 0.33 Cs-134 Cs-137 Fe-59 K-40 Mn-54 Nb-95 05/05/06 -0.01 +/- 0.03 0.54 +/- 0.08 0.07 +/- 0.08 11.50 +/- 1.30 0.01 +/- 0.04 -0.01 +/- 0.06 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 05/05/06 0.04 +/- 0.04 0.00 +/- 0.37 0.02 +/- 0.09 1.00+/- 0.17 -0.03 +/- 0.17 -0.01 +/- 0.06 14-C Be-7 Ce-141 Ce-144 Co-58 Co-60 Cr-51 05/05/06 0.03 +/- 0.35 -0.03 +/- 0.07 0.00 +/- 0.25 -0.03 +/- 0.04 -0.01 +/- 0.03 -0.08 +/- 0.34 Cs-134 Cs-137 Fe-59 K-40 Mn-54 Nb-95 05/05/06 0.00 +/- 0.04 1.12+/- 0.11 -0.05 +/-+0.07 12.70 +/- 1.30 0.01 +/- 0.04 -0.02 +/- 0.04 Ru-103 Ru-i06 Sb-125 Th-228 Zn-65 Zr-95 05/05/06 -0.01 +/- 0.04 -0.13 +/- 0.32 -0.08 +/- 0.12 1.30 +/- 0.18 0.00 +/- 0.17 -0.02 +/- 0.05

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 7, Cow Milk No data collected during 2006

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 8, Goat Milk (pCi/L) Page 1 of 1 Location Collection Isotope Date 21 Ba-140 Cs-134 Cs-137 1-131 K-40 La-140 05/10/06 -0.70 +/- 5.40 1.80 +/- 4.10 3.40 +/- 4.30 0.02 +/- 0.21 1820.00 +/- 150.00 -0.80 +/- 6.20 05/24/06 3.30 +/- 4.60 1.40 +/- 3.90 9.40 +/- 4.80 0.15 +/- 0.26 1280.00 +/- 120.00 3.80 +/- 5.30 06/14/06 1.10 +/- 6.60 1.10 +/- 4.30 3.30 +/- 4.20 -0.11 +/- 0.04 1470.00 +/- 160.00 1.30 +/- 7.60 06/28/06 0.50 +/- 7.00 2.50 +/- 4.10 5.70 +/- 4.40 0.08 +/- 0.27 1320.00 +/- 120.00 0.60 +/- 8.10 07/26/06 -2.20 +/- 5.10 2.20 +/- 3.80 -2.00 +/- 4.70 -0.04 +/- 0.02 950.00 +/- 130.00 -2.50 +/- 5.90 08/23/06 -3.00 +/- 5.50 0.30 +/- 3.30 7.70 +/- 4.40 0.01 +/- 0.31 950.00 +/- 98.00 -3.50 +/- 6.40 Sr-89 Sr-90 06/28/06 0.80 +/- 5.70 0.90 +/- 1.10 08/23/06 -2.80 +/- 5.20 0.70 +/- 1.10 24-C Ba-140 Cs-134 Cs-137 1-131 K-40 La-140 04/26/06 -4.50 +/- 6.00 -3.10 +/- 4.70 4.20 +/- 4.30 0.02 +/- 0.16 1750.00 +/- 160.00 -5.20 +/- 6.90 06/14/06 7.60 +/- 7.10 1.00 +/- 5.90 2.80 +/- 5.50 -0.07 +/- 0.03 1600.00 +/- 210.00 8.80 +/- 8.20 06/28/06 4.30 +/- 7.40 0.50 +/- 4.30 5.90 +/- 4.20 0.07 +/- 0.30 1710.00 +/- 160.00 4.90 +/- 8.60 07/12/06 2.90 +/- 6.90 -2.80 +/- 5.30 4.00 +/- 4.70 -0.04 +/- 0.02 1600.00 +/- 210.00 3.30 +/- 7.90 07/26/06 -1.00+/- 6.60 -1.70 +/- 4.20 2.60 +/- 4.20 -0.05 +/- 0.02 1380.00 +/- 140.00 -1.10 +/- 7.60 08/09/06 -1.30+/- 4.20 0.40 +/- 3.60 7.50 +/- 5.30 0.45 +/- 0.55 1860.00 +/- 140.00 -1.50 +/- 4.90 08/23/06 2.10+/- 5.40 -0.30 +/- 3.60 12.90 +/- 4.80 -0.07 +/- 0.02 1890.00 +/- 130.00 2.40 +/- 6.30 10/11/06 -2.30 +/- 5.30 1.20 +/- 3.80 4.70 +/- 5.30 -0.06 +/- 0.02 1690.00 +/- 150.00 -2.70 +/- 6.20 Sr-89 Sr-90 06/28/06 -2.50 +/- 4.00 0.84 +/- 0.79 08/23/06 4.60 +/- 5.70 0.10 +/- 1.10

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 9, Pasture Grass (pCi/g Dry) Page I of 4 Location Collection Isotope Date 21 Ba-140 Be-7 Ce-141 Ce-144 Co-58 Co-60 0 1/11/06 -0.004 +/- 0.037 G -0.280 +/- 0.220 0.007 +/- 0.038 -0.070 +/- 0.130 0.005 +/- 0.027 -0.028 +/- 0.042 02/15/06 -0.021 +/- 0.078 G -0.0 10 +/- 0.200 -0.015 +/- 0.043 0.000 +/- 0.120 0.004 +/- 0.030 0.022 +/- 0.028 03/22/06 -0.025 +/- 0.03 1 G 0.230 +/- 0.210 -0.005 +/- 0.030 0.070 +/- 0.110 0.008 +/- 0.025 -0.0 18 +/- 0.032 04/12/06 -0.005 +/- 0.036 G 0.120 +/- 0.190 -0.044 +/- 0.031 0.036 +/- 0.099 -0.007 +/- 0.024 0.004 +/-0.037 04/26/06 0.008 +/- 0.03 6 G -0.040 +/- 0.300 -0.032 +/- 0.044 0.000 +/- 0.140 -0.006 +/- 0.034 -0.02 1 +/- 0.037 07/12/06 -0.024 +/-0.062 0.410 +/- 0.340 -0.013 +/- 0.042 -0.010 +/- 0.130 0.006 +/- 0.033 0.0 19 +/- 0.043 08/09/06 -0.013+/-0.018 0.190 +/-0.190 0.018 +/- 0.022 0.050 +/- 0.071 -0.005 +/- 0.016 0.000 +/- 0.024 08/23/06 -0.044 +/-0.040 0.270 +/- 0.200 -0.006 +/- 0.023 0.007 +/- 0.077 -0.008 +/- 0.020 0.000 +/-0.026 09/06/06 -0.027 +/-0.021 0.860 +/- 0.130 -0.010 +/- 0.013 0.015 +/- 0.039 0.005 +/- 0.009 -0.0 12 +/- 0.012 09/20/06 -0.011 +/-0.011 1.640 +/- 0.200 0.005 +/- 0.009 -0.0 19 +/- 0.033 -0.003 +/- 0.009 0.006 +/- 0.0 12 10/11/06 0.010 +/- 0.029 0.900 +/- 0.180 0.002 +/- 0.0 15 -0.027 +/- 0.043 -0.009 +/- 0.0 15 0.008 +/- 0.0 14 10/25/06 0.000 +/- 0.065 2.150 +/- 0.400 -0.0 17 +/- 0.030 -0.003 +/- 0.087 0.002 +/- 0.020 -0.0 12 +/- 0.028 11/15/06 -0.034 +/- 0.058 2.670 +/- 0.360 -0.010 +/- 0.031 0.069 +/- 0.07 1 -0.005 +/- 0.018 0.000 +/- 0.0 14 11/29/06 0.005 +/- 0.032 2.780 +/- 0.260 -0.007 +/- 0.02 1 -0.040 +/- 0.060 -0.003 +/- 0.014 -0.004 +/- 0.0 12 12/13/06 -0.020 +/- 0.100 G 1.600 +/- 0.340 -0.054 +/- 0.060 0.030 +/-10.100 0.004 +/- 0.026 0.0 17 +/- 0.025 Cr-Si Cs-134 Cs-137 Fe-59 1-13 1 K-40 01/11/06 0.020 +/- 0.250 0.002 +/- 0.031 -0.018 +/- 0.033 -0.018 +/- 0.069 -0.003 +/- 0.001 8.800+/- 1.100 02/15/06 0.150 +/- 0.310 -0.0 15 +/- 0.024 -0.0 15 +/- 0.021 0.024 +/- 0.078 -0.002 +/- 0.00 1 10.300+/- 1.000 03/22/06 0.020 +/- 0.2 10 -0.002 +/- 0.027 -0.006 +/- 0.028 0.032 +/- 0.061 0.003 +/- 0.009 9.100+/- 1.000 04/12/06 0.000 +/- 0.220 0.027 +/-0.027 -0.004 +/- 0.025 -0.0 17 +/- 0.054 0.005 +/- 0.010 8.700 +/-0.930 04/26/06 0.100 +/- 0.290 0.006 +/-0.030 0.005 +/- 0.027 0.042 +/- 0.084 -0.008 +/- 0.0 14 9.300 +/-1.300 07/12/06 -0.050 +/- 0.280 0.006 +/-0.032 0.0 12 +/- 0.032 0.034 +/- 0.077 0.0 12 +/- 0.02 1 -6.300+/-1.100 08/09/06 0.040 +/- 0.140 0.027 +/-0.0 19 0.006 +/- 0.018 -0.010 +/- 0.039 -0.001 +/- 0.017 5.640+/-0.640 08/23/06 0.060 +/- 0.150 0.005 +/-0.020 0.023 +/- 0.022 0.025 +/- 0.053 0.000 +/- 0.0 18 3.510+/-0.670 09/06/06 0.000 +/- 0.090 0.003 +/-0.010 0.011 +/- 0.010 0.007 +/- 0.021 -0.008 +/- 0.003 4.090 +/-0.3 00 09/20/06 -0.032 +/- 0.056 0.008 +/-0.009 0.002 +/- 0.008 -0.007 +/- 0.023 0.005 +/- 0.0 16 3.870 +/-0.470 10/11/06 0.020 +/- 0.110 0.00 1 +/-0.0 14 0.020 +/- 0.013 0.008 +/- 0.036 0.005 +/- 0.0 14 4.760+/-0.520 10/25/06 0.010 +/- 0.220 0.007 +/-0.020 -0.010 +/- 0.021 0.000 +/- 0.054 0.002 +/- 0.016 6.240 +/-0.820 11/15/06 -0.040 +/- 0.180 -0.002 +/- 0.015 0.003 +/- 0.015 -0.018 +/- 0.043 0.016 +/- 0.027 4.440 +/- 0.550 11/29/06 -0.020 +/- 0.150 -0.013 +/- 0.021 -0.004 +/- 0.012 0.008 +/- 0.032 -0.004 +/- 0.00 1 5.3 80 +/- 0.430 12/13/06 0.130 +/- 0.340 -0.0 17 +/- 0.026 0.030 +/- 0.033 -0.085 +/- 0.070 -0.020 +/- 0.270 20.010 +/- 0.840 La-140 Mn-54 Nb-95 Ru-103 Ru-106 Sb-125 01/11/06 -0.005 +/- 0.042 0.017 +/- 0.028 0.009 +/- 0.046 -0.002 +/- 0.024 0.080 +/- 0.240 -0.007 +/- 0.068 02/15/06 -0.024 +/- 0.090 0.002 +/- 0.025 -0.033 +/- 0.039 0.000 +/- 0.032 -0.010 +/- 0.240 0.000 +/- 0.058 03/22/0 6 -0.029 +/- 0.03 6 0.0 17 +/- 0.023 -0.0 12 +/- 0.029 -0.026 +/- 0.022 0.060 +/- 0.240 -0.004 +/- 0.065 04/12/06 -0.005 +/- 0.042 0.003 +/- 0.022 0.004 +/- 0.024 0.007 +/- 0.023 0.0 10 +/- 0.2 10 0.003 +/- 0.058 04/26/06 0.009 +/- 0.04 1 -0.006 +/-0.031 -0.0 17 +/- 0.035 0.022 +/- 0.038 -0.260 +/- 0.270 0.000 +/- 0.075 07/12/06 -0.027 +/- 0.071 -0.008 +/- 0.032 -0.003 +/- 0.039 0.023 +/- 0.030 -0.040 +/- 0.300 -0.050 +/- 0.074 08/09/06 -0.015 +/- 0.020 0.006 +/- 0.016 -0.003 +/- 0.018 -0.007 +/- 0.017 0.020 +/- 0.150 -0.060 +/-0.043 08/23/06 -0.050 +/- 0.046 -0.007 +/- 0.018 -0.014 +/- 0.025 0.002 +/- 0.020 0.000 +/- 0.160 0.003 +/- 0.04 1 09/06/0 6 -0.031 +/- 0.024 0.001 +/- 0.009 0.004 +/- 0.011 -0.003 +/- 0.009 0.0 13 +/- 0.085 0.004 +/- 0.02 1 09/20/06 -0.013 +/- 0.013 -0.006 +/- 0.008 0.0 10 +/- 0.009 0.003 +/- 0.007 -0.0 13 +/- 0.068 0.011 +/- 0.022 10/11/06 0.011 +/- 0.034 -0.009 +/- 0.0 14 -0.005 +/- 0.016 0.005 +/- 0.013 -0.010 +/- 0.110 0.010 +/- 0.032 10/25/06 0.000 +/- 0.075 0.004 +/- 0.020 -0.0 19 +/- 0.030 0.004 +/- 0.023 -0.130 +/- 0.200 -0.023 +/- 0.050 11/15/06 -0.039 +/- 0.067 0.023 +/- 0.0 16 -0.005 +/- 0.025 0.013 +/- 0.020 -0.070 +/- 0.150 -0.045 +/- 0.036 11/29/06 0.005 +/- 0.037 0.003 +/- 0.011 -0.003 +/- 0.017 -0.002 +/- 0.016 -0.030 +/- 0.110 -0.002 +/- 0.029 12/13/06 -0.030 +/- 0.120 0.02 1 +/- 0.023 0.006 +/- 0.03 6 0.005 +/- 0.030 -0.140 +/- 0.220 -0.013 +/- 0.056

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 9, Pasture Grass (pCilg Dry) Page 2 of 4 Location Collection Isotope Date 21 Th-228 Zn-65 Zr-95 01/11/06 0.010 +/- 0.110 0.057 +/- 0.070 -0.032 +/- 0.047 02/15/06 0.035 +/- 0.099 -0.005 +/- 0.054 -0.011 +/- 0,054 03/22/06 0.006 +/- 0.099 0.0 14 +/- 0.062 0.011 +/- 0.039 04/12/06 0.0 10 +/- 0.096 0.008 +/- 0.057 -0.008 +/- 0.03 8 04/26/06 -0.080 +/- 0.110 -0.025 +/- 0.072 0.000 +/- 0.055 07/12/06 0.140 +/- 0.130 -0.038 +/- 0.067 0.026 +/- 0.058 08/09/06 0.048 +/- 0.069 -0.0 15 +/- 0.043 -0.028 +/- 0.029 08/23/0 6 -0.029 +/- 0.062 -0.047 +/- 0.049 -0.0 13 +/- 0.034 09/06/06 0.019 +/- 0.045 -0.0 10 +/- 0.022 -0.007 +/- 0.017 09/20/06 0.033 +/- 0.036 -0.020 +/-0.028 -0.011 +/-0.015 10/11/06 0.064 +/- 0.050 0.045 +/- 0.061 0.0 13 +/- 0.027 10/25/06 0.000 +/- 0.100 -0.029 +/- 0.067 -0.008 +/- 0.041 11/15/06 -0.005 +/- 0.065 -0.033 +/- 0.039 -0.046 +/- 0.032 11/29/06 0.033 +/- 0.056 0.002 +/- 0.047 0.015 :+/- 0.026 12/13/06 0.117 +/- 0.082 -0.001 +/- 0.059 0.037 +/- 0.048 22 Ba-140 Be-7 Ce-141 Ce-144 Co-58 Co-60 01/11/06 -0.022 +/- 0,037 G 0.2 10 +/- 0.200 0.028 +/- 0.04 1 0.020 +/- 0.120 -0.021 +/- 0.030 0.020 +/- 0.033 02/15/06 -0.130 +/- 0.110 G 0.130 +/- 0.320 0.0 12 +/- 0.054 0.090 +/- 0.120 0.0 14 +/- 0.034 0.012 +/- 0.032 03/22/06 -0.019 +/- 0.042 G 0.950 +/- 0.320 -0.034 +/- 0.047 0.070 +/- 0.140 0.0 14 +/- 0.030 0.027 +/- 0.032 04/12/06 0.025 +/- 0.059 G 1,120 +/- 0.280 -0.004 +/- 0.024 -0.0 14 +/- 0.083 -0.007 +/-0.028 0.046 +/- 0.033 04/26/06 -0.022 +/- 0.051 G 3.050+/- 0.340 -0.011 +/- 0.023 -0.074 +/- 0.080 -0.007 +/-0.026 0.009 +/- 0.028 05/10/06 -0.004 +/-0.033 0.260 +/- 0.170 -0.011 + 0.020 -0.068 +/- 0.072 0.006 +/-0.0 17 0.025 +/- 0.032 05/24/06 -0.024 +/-0.035 0.850 +/- 0.330 -0.0 13 +/- 0.024 -0.087 +/- 0.092 0.008 +/-0.022 0.020 +/- 0.034 06/14/06 -0.030 +/-0.120 0.780 +/- 0.430 -0.009 +/- 0.044 -0.020 +/-=0. 100 -0.0 13 +/-0.032 0.012 +/- 0.032 06/28/06 -0.023 +/-0.093 1.230 +/- 0.360 0.012 +/- 0.028 -0.023 +/- 0.083 -0.028 +/-0.03 0 0.000 +/- 0.03 0 07/12/06 -0.025 +/-0.044 0.5 10 +/- 0.300 0.009 +/- 0.03 2 0.010 +/-0.120 -0.0 13 +/-0.028 0.030 +/- 0.027 07/26/06 0.0 18 +/- 0.068 0.980 +/- 0.340 -0.029 +/- 0.025 0.023 +/- 0.083 0.000 +/-0.031 0.020 +/- 0.031 08/09/0 6 -0.009 +/- 0.02 7 1.800 +/- 0.290 0.007 +/- 0.028 0.042 +/- 0.084 -0.005 +/-0.019 -0.006 +/- 0.024 08/23/06 -0.0 18 +/- 0.050 0.760 +/- 0.370 -0.009 +/- 0.034 0.070 +/-0.110 0.006 +/-0.023 -0.012 +/- 0.035 09/06/06 -0.009 +/- 0.024 1.710 +/- 0.160 0.009 +/- 0.0 12 -0.019 +/- 0.032 -0.002 +/-0.011 -0.002 +/- 0.0 12 09/20/06 0.003 +/- 0.009 3.080 +/- 0.190 0.001 +/- 0.008 -0.011 +/- 0.028 -0.009 +/-0.007 0.002 +/- 0.009 10/11/06 -0.025 +/- 0.040 1.240 +/- 0.260 0.004 +/- 0.022 -0.014 +/- 0.068 0.003 +/-0.019 -0.010 +/- 0.023 10/25/06 -0.040 +/- 0.047 2.920 +/- 0.280 0.0 10 +/- 0.020 -0.0 13 +/- 0.062 0.019 +/-0.017 -0.005 +/- 0.020 11/15/06 0.045 +/- 0.070 2.670 +/- 0.380 0.031 +/- 0.041 0.045 +/- 0.081 0.001 +/-0.020 0.013 +/- 0.02 1 11/29/06 0.000 +/- 0.150 G 0.0 10 +/- 0.270 0.009 +/- 0.049 -0.05 1 +/- 0.096 -0.010 +/-0.029 0.011 +/- 0.022 12/13/06 -0.05 1 +/- 0.092 G 1.820 +/- 0.220 -0.035 +/- 0.043 0.021 +/- 0.069 0.001 +/-0.018 -0.011 +/- 0.015 Cr-51 Cs-134 Cs-137 Fe-59 1-131 K-40 01/11/06 -0.140 +/- 0.230 -0.002 +/- 0.032 0.008 +/- 0.028 0.048 +/-0.062 0.006 +/- 0.019 15.460 +/- 0.880 02/15/06 0.290 +/- 0.400 -0.002 +/- 0.033 -0.002 +/- 0.027 -0.003 +/-0.088 -0.002 +/- 0.001 10.440 +/- 0.780 03/22/06 -0.100 +/- 0.250 0.022 +/- 0.033 0.023 +/- 0.030 -0.012 +/-0.059 0.0 15 +/- 0.025 7.070 +/- 0.75 0 04/12/06 -0.030 +/- 0.200 0.003 +/- 0.030 0.024 +/- 0.026 -0.012+/-0.061 -0.003 +/- 0.001 4.540 +/- 0.680 04/26/06 -0.190 +/- 0.180 0.0 17 +/- 0.028 0.020 +/- 0.024 -0.037 +/-0.055 0.0 12 +/- 0.026 2.690 +/- 0.550 05/10/06 -0.020 +/- 0.160 0.003 +/- 0.023 -0.00 1 +/- 0.020 -0.004 +/- 0.046 -0.003 +/- 0.00 1 5.040 +/- 0.770 05/24/06 -0.160 +/- 0.170 0.020 +/- 0.027 0.027 +/- 0.032 -0.005 +/- 0.050 -0.003 +/- 0.00 1 5.650 +/- 0.910 06/14/06 -0.160 +/- 0.290 -0.002 +/- 0.026 0.037 +/-0.042 -0.092 +/- 0.087 -0.005 +/- 0.002 4.870 +/- 0.920 06/28/06 0.040 +/- 0.250 -0.0 16 +/- 0.028 0.0 14 +/- 0.024 0.007 +/- 0,067 -0.002 +/- 0.00 1 4.270 +/- 0.830 07/12/06 -0.090 +/- 0.280 -0.009 +/- 0.027 0.013 +/- 0.03 1 0.024 +/- 0.063 -0.003 +/- 0.00 1 5.630 +/- 0.930 07/26/06 0.020 +/- 0.220 0.008 +/- 0.03 1 0.000 +/- 0.028 0.0 14 +/- 0.055 0.004 +/- 0.018 3.8 10 +/- 0.860 08/09/06 0.050 +/- 0.170 -0.003 +/- 0.02 1 0.011 +/- 0.019 -0.005 +/- 0.04 1 -0.009 +/- 0.016 4.920 +/- 0.610 08/23/06 0.020 +/- 0.220 0.0 10 +/- 0.026 -0.014 +/- 0.029 0.040 +/- 0.06 1 0.0 10 +/- 0.024 4.360 +/- 0.740 09/06/06 -0.036 +/- 0.079 0.006 +/- 0.011 0.004 +/- 0.0 10 0.000 +/- 0.02 6 0.001 +/- 0.015 4.430 +/- 0.370

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 9, Pasture Grass (pCi/g Dry) Page 3 of 4 Location Collection Isotope Date 22 Cr-51 Cs-134 Cs-137 Fe-59 1-131 K-40 09/20/06 -0.013 +/- 0.053 -0.001 +/- 0.007 0.020 +/- 0.010 -0.002 +/- 0.016 0.006 +/- 0.017 4.610 +/- 0.330 10/11/06 0.150+/-0.160 -0.003 +/- 0.018 -0.001 +/- 0.019 -0.033 +/- 0.046 0.006 +/- 0.015 5.320 +/- 0.600 10/25/06 0.060 +/- 0.140 0.015 +/- 0.017 0.003 +/- 0.015 0.024 +/- 0.039 -0.005 +/- 0.002 5.570 +/- 0.530 11/15/06 -0.060 +/- 0.250 0.009 +/- 0.018 0.006 +/- 0.018 0.007 +/- 0.051 -0.002 +/- 0.015 3.700 +/- 0.530 11/29/06 -0.310 +/- 0.380 0.010 +/- 0.033 -0.023 +/- 0.021 0.056 +/- 0.078 -0.060 +/- 0.480 15.240 +/- 0.680 12/13/06 0.060 +/- 0.240 -0.009 +/- 0.020 0.023 +/- 0.017 0.000 +/- 0.044 0.100 +/- 0.260 8.930 +/- 0.420 La-140 Mn-54 Nb-95 Ru-103 Ru-106 Sb-125 01/11/06 -0.025 +/- 0.043 -0.005 +/- 0.028 -0.058 +/- 0.036 0.003 +/- 0.028 -0.050 +/- 0.260 -0.010 +/- 0.066 02/15/06 -0.150+/- 0.130 0.003 +/- 0.030 0.034 +/- 0.045 0.048 +/- 0.042 -0.040 +/- 0.270 0.001 +/- 0.068 03/22/06 -0.022 +/- 0.048 0.008 +/- 0.030 0.034 +/- 0.033 -0.015 +/- 0.032 0.120 +/- 0.290 -0.040 +/- 0.072 04/12/06 0.029 +/- 0.068 -0.020 +/- 0.027 -0.052 +/- 0.037 0.021 +/- 0.028 -0.210 +/- 0.220 -0.003 +/- 0.063 04/26/06 -0.026 +/- 0.058 -0.003 +/- 0.024 -0.018 +/- 0.035 -0.005 +/- 0.024 0.050 +/- 0.190 0.006 +/- 0.057 05/10/06 -0.005 +/- 0.038 0.001 +/- 0.017 -0.014 +/- 0.020 -0.005 +/- 0.017 0.040 +/- 0.180 0.006 +/- 0.042 05/24/06 -0.028 +/- 0.040 -0.008 +/- 0.020 0.002 +/- 0.023 -0.014 +/- 0.021 -0.090 +/- 0.190 0.000 +/- 0.043 06/14/06 -0.040 +/- 0.140 0.002 +/- 0.028 -0.008 +/- 0.049 -0.002 +/- 0.037 -0.070 +/- 0.220 0.016 +/- 0.065 06/28/06 -0.030 +/- 0.110 0.019 +/- 0.027 0.007 +/- 0.034 0.030 +/- 0.029 -0.120+/- 0.180 -0.036 +/- 0.051 07/12/06 -0.028 +/- 0.051 0.000 +/- 0.027 0.020 +/- 0.032 0.009 +/- 0.025 0.060 +/- 0.220 0.009 +/- 0.056 07/26/06 0.021 +/- 0.078 0.018 +/- 0.021 0.006 +/- 0.038 -0.030 +/- 0.031 -0.170 +/- 0.220 -0.065 +/- 0.063 08/09/06 -0.010 +/- 0.032 -0.018 +/- 0.018 0.023 +/- 0.024 0.005 +/- 0.021 -0.030 +/- 0.170 0.008 +/- 0.045 08/23/06 -0.021 +/- 0.058 -0.005 +/- 0.029 0.010 +/- 0.032 0.005 +/- 0.025 0.190 +/- 0.250 0.014 +/- 0.060 09/06/06 -0.010 +/- 0.027 0.001 +/- 0.009 -0.001 +/- 0.015 -0.006 +/- 0.009 -0.073 +/- 0.082 -0.001 +/- 0.023 09/20/06 0.003 +/- 0.011 0.002 +/- 0.007 0.003 +/- 0.008 -0.006 +/- 0.007 0.015 +/- 0.056 -0.002 +/- 0.015 10/11/06 -0.029 +/- 0.046 -0.007 +/- 0.017 0.021 +/- 0.021 -0.006 +/- 0.017 -0.190 +/- 0.160 -0.015 +/- 0.039 10/25/06 -0.046 +/- 0.054 0.002 +/- 0.016 0.006 +/- 0.020 0.007 +/- 0.016 -0.010 +/- 0.130 0.020 +/- 0.036 11/15/06 0.051 +/- 0.081 0.007 +/- 0.016 0.029 +/- 0.031 -0.007 +/- 0.023 0.010 +/- 0.160 -0.033 +/- 0.039 11/29/06 0.000 +/- 0.180 -0.009 +/- 0.023 0.005 +/- 0.043 0.004 +/- 0.037 -0.050 +/- 0.210 0.034 +/- 0.053 12/13/06 -0.060 +/- 0.110 -0.004 +/- 0.015 0.000 +/- 0.026 -0.009 +/- 0.021 -0.060 +/- 0.140 -0.022 +/- 0.036 Th-228 Zn-65 Zr-95 01/11/06 0.000 +/- 0.140 0.016 +/- 0.097 0.002 +/- 0.049 02/15/06 -0.110 +/- 0.140 -0.043 +/- 0.073 0.056 +/- 0.065 03/22/06 0.040 +/- 0.170 -0.058 +/- 0.073 0.003 +/- 0.052 04/12/06 0.110+/- 0.100 -0.014 +/- 0.060 -0.008 +/- 0.048 04/26/06 0.010 +/- 0.120 -0.020 +/- 0.100 0.041 +/- 0.045 05/10/06 -0.011 +/- 0.079 -0.043 +/- 0.047 0.020 +/- 0.031 05/24/06 0.018 +/- 0.093 0.042 +/- 0.051 -0.020 +/- 0.036 06/14/06 -0.026 +/- 0.099 -0.024 +/- 0.073 0.011 +/- 0.065 06/28/06 -0.006 +/- 0.087 0.036 +/- 0.054 -0.027 +/- 0.045 07/12/06 0.090 +/- 0.100 -0.016 +/- 0.064 0.040 +/- 0.048 07/26/06 -0.020 +/- 0.100 -0.026 +/- 0.078 0.006 +/- 0.048 08/09/06 0.060 +/- 0.110 0.002 +/- 0.089 -0.007 +/- 0.035 08/23/06 0.050 +/- 0.100 -0.019 +/- 0.056 -0.060 +/- 0.044 09/06/06 0.041 +/- 0.051 -0.009 +/- 0.025 0.007 +/- 0.017 09/20/06 0.040 +/- 0.033 -0.008 +/- 0.018 -0.009 +/- 0.012 10/11/06 0.018 +/- 0.089 0.000 +/- 0.042 -0.003 +/- 0.037 10/25/06 0.006 +/- 0.072 0.013 +/- 0.039 0.016 +/- 0.031 11/15/06 0.098 +/- 0.083 0.011 +/- 0.043 0.018 +/- 0.036 11/29/06 0.010 +/- 0.120 -0.049 +/- 0.055 0.024 +/- 0.053 12/13/06 0.105 +/- 0.061 0.056 +/- 0.059 0.015 +/- 0.032

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 9, Pasture Grass (pCi/g Dry) Page 4 of 4 Location Collection Isotope Date 24-C Ba-140 Be-7 Ce-141 Ce-144 Co-58 Co-60 01/11/06 0.007 +/- 0.038 G 0.800 +/- 0.270 0.010 +/- 0.036 -0.110 +/- 0.110 0.001 +/- 0.023 0.014 +/- 0.025 02/15/06 0.010 +/- 0.120 G -0.110 +/- 0.260 0.008 +/- 0.043 -0.100 +/- 0.110 0.012 +/- 0.034 0.017 +/- 0.040 03/22/06 0.022 +/- 0.040 G 0.030 +/- 0.220 -0.003 +/- 0.037 -0.090 +/- 0.130 0.006 +/- 0.026 0.005 +/- 0.029 04/12/06 -0.009 +/- 0.045 G 0.070 +/- 0.210 -0.009 +/- 0.040 -0.090 +/- 0.110 -0.008 +/- 0.027 -0.006 +/- 0.030 05/10/06 -0.008 +/- 0.028 0.250 +/- 0.200 -0.001 +/- 0.020 0.049 +/- 0.073 -0.021 +/- 0.021 0.000 +/- 0.025 05/24/06 0.018 +/- 0.029 0.330 +/- 0.260 -0.005 +/- 0.024 0.033 +/- 0.089 -0.012 +/- 0.025 0.009 +/- 0.036 09/06/06 -0.018 +/- 0.020 1.360 +/- 0.140 -0.014 +/- 0.016 -0.031 +/- 0.032 -0.006 +/- 0.009 0.002 +/- 0.012 09/20/06 0.002 +/- 0.007 1.170 +/- 0.160 -0.001 +/- 0.008 -0.013 +/- 0.029 0.004 +/- 0.008 -0.003 +/- 0.013 10/25/06 0.030 +/- 0.220 3.740 +/- 0.570 -0.013 +/- 0.040 0.070+/- 0.110 -0.013 +/- 0.032 0.028 +/- 0.030 11/15/06 0.055 +/- 0.086 2.320 +/- 0.400 0.006 +/- 0.025 -0.033 +/- 0.072 -0.005 +/- 0.024 0.002 +/- 0.021 11/29/06 0.036+/- 0.060 3.220 +/- 0.400 -0.009 +/- 0.026 -0.046 +/- 0.072 -0.007 +/- 0.021 -0.012 +/- 0.023 12/13/06 -0.090 +/- 0.130 G 2.500 +/- 0.440 0.035 +/- 0.057 -0.120+/- 0.130 -0.037 +/- 0.034 -0.015 +/- 0.029 Cr-51 Cs-134 Cs-137 Fe-59 1-131 K-40 01/11/06 0.040 +/- 0.220 -0.004 +/- 0.028 0.014 +/- 0.034 0.047 +/- 0.048 0.002 +/- 0.015 7.690 +/- 0.640 02/15/06 0.200 +/- 0.290 0.004 +/- 0.030 0.052 +/- 0.037 -0.072 +/- 0.085 -0.004 +/- 0.001 13.190+/- 0.910 03/22/06 0.150 +/- 0.240 -0.005 +/- 0.031 0.025 +/- 0.038 0.010 +/- 0.055 0.010+/-0.019 12.050+/- 0.810 04/12/06 -0.040 +/- 0.240 0.000 +/- 0.028 0.063 +/- 0.039 0.012 +/- 0.060 0.003 +/- 0.012 15.030 +/- 0.830 05/10/06 -0.010 +/- 0.130 0.007 +/- 0.023 -0.012 +/- 0.020 -0.019 +/- 0.044 -0.003 +/- 0.001 5.960 +/- 0.840 05/24/06 -0.080 +/- 0.140 0.025 +/- 0.027 0.006 +/- 0.019 0.029 +/- 0.056 -0.003 +/- 0.001 6.000 +/- 1.000 09/06/06 0.049 +/- 0.078 0.009 +/- 0.009 -0.007 +/- 0.009 -0.004 +/- 0.022 -0.007 +/- 0.002 4.550 +/- 0.320 09/20/06 -0.026 +/- 0.055 0.000 +/- 0.009 0.014 +/- 0.009 0.002 +/- 0.017 -0.002 +/- 0.001 4.150 +/- 0.420 10/25/06 0.070 +/- 0.270 0.002 +/- 0.030 -0.012 +/- 0.025 -0.007 +/- 0.076 -0.006 +/- 0.002 6.200 +/- 1.000 11/15/06 0.110 +/- 0.200 0.002 +/- 0.019 0.003 +/- 0.015 -0.011 +/- 0.052 -0.012 +/- 0.004 4.180 +/- 0.690 11/29/06 0.190 +/- 0.200 -0.010 +/- 0.021 -0.017 +/- 0.017 0.020 +/- 0.050 0.010 +/- 0.020 4.460 +/- 0.650 12/13/06 -0.630 +/- 0.420 -0.011 +/- 0.032 0.052 +/- 0.041 0.054 +/- 0.085 0.160 +/- 0.300 11.550 +/- 0.800 La-140 Mn-54 Nb-95 Ru-103 Ru-106 Sb-125 01/11/06 0.008 +/- 0.044 0.013 +/- 0.023 -0.003 +/- 0.026 -0.001 +/- 0.023 -0.120 +/- 0.230 0.034 +/- 0.062 02/15/06 0.010 +/- 0.140 0.000 +/- 0.030 0.018 +/- 0.056 0.002 +/- 0.036 0.100 +/- 0.240 0.022 +/- 0.065 03/22/06 0.025 +/- 0.046 0.012 +/- 0.026 0.001 +/- 0.029 -0.030 +/- 0.025 -0.160 +/- 0.250 0.029 +/- 0.071 04/12/06 -0.010 +/- 0.052 -0.003 +/- 0.027 0.003 +/- 0.038 -0.009 +/- 0.029 -0.050 +/- 0.250 -0.002 +/- 0.061 05/10/06 -0.009 +/- 0.032 -0.007 +/- 0.022 -0.011 +/- 0.023 0.000 +/- 0.017 0.060 +/- 0.160 0.016 +/- 0.046 05/24/06 0.021 +/- 0.033 0.009 +/- 0.020 0.001 +/- 0.025 0.004 +/- 0.018 0.020+/- 0.170 0.038 +/- 0.051 09/06/06 -0.021 +/- 0.023 0.003 +/- 0.008 0.001 +/- 0.010 -0.001 +/- 0.010 0.006 +/- 0.080 0.007 +/- 0.020 09/20/06 0.002 +/- 0.008 0.007 +/- 0.009 0.001 +/- 0.010 0.000 +/- 0.007 0.010+/- 0.064 0.000 +/- 0.019 10/25/06 -0.020 +/- 0.120 0.017 +/- 0.028 -0.026 +/- 0.041 -0.034 +/- 0.031 0.070 +/- 0.220 0.024 +/- 0.062 11/15/06 0.064 +/- 0.099 0.000 +/- 0.019 0.002 +/- 0.029 0.009 +/- 0.025 -0.120+/- 0.150 0.009 +/- 0.038 11/29/06 0.042 +/- 0.069 0.011 +/- 0.019 -0.014 +/- 0.032 0.004 +/- 0.020 -0.090 +/- 0.160 -0.005 +/- 0.043 12/13/06 -0.100 +/- 0.140 -0.006 +/- 0.029 0.031 +/- 0.046 0.020 +/- 0.036 0.360 +/- 0.260 0.048 +/- 0.071 Th-228 Zn-65 Zr-95 01/11/06 0.100 +/- 0.130 -0.035 +/- 0.058 -0.005 +/- 0.043 02/15/06 0.080 +/- 0.140 0.050 +/- 0.066 -0.021 +/- 0.060 03/22/06 0.094 +/- 0.088 -0.085 +/- 0.065 -0.022 +/- 0.047 04/12/06 -0.010 +/- 0.120 0.006 +/- 0.063 0.014 +/- 0.047 05/10/06 0.030 +/- 0.081 0.031 +/- 0.056 0.025 +/- 0.037 05/24/06 0.045 +/- 0.095 -0.012 +/- 0.056 0.021 +/- 0.046 09/06/06 0.037 +/- 0.044 0.008 +/- 0.022 -0.010 +/- 0.015 09/20/06 0.033 +/- 0.038 -0.018 +/- 0.022 -0.008 +/- 0.017 10/25/06 0.100+/- 0.120 -0.035 +/- 0.073 -0.020 +/- 0.040 11/15/06 0.060 +/- 0.063 0.034 +/- 0.047 0.045 +/- 0.043 11/29/06 0.009 +/- 0.073 -0.014 +/- 0.052 -0.012 +/- 0.038 12/13/06 0.040+/- 0.150 0.130+/- 0.110 -0.012 +/- 0.058

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 10, Well Water (pCi/L) Page l of 4 Location Collection Isotope Date 71 Ba-140 Be-7 Co-58 Co-60 Cr-51 Cs-134 03/16/06 -0.6 +/- 4.9 -6.0 21.0 -1.5 +/- 2.4 0.4 +/- 3.0 12.0 24.0 0.0 +/- 2.7 06/14/06 4.5+/-6.7 12.0 43.0 -0.4 +/- 4.2 -0.6 +/- 4.2 2.0 +/- 36.0 0.8 +/- 4.3 09/19/06 -1.3+/-6.0 -5.0 32.0 -5.1 +/- 3.9 -2.1+/-4.1 -18.0 41.0 0.6 +/- 4.4 12/20/06 1.9+/-4.3 -1.0 23.0 0.7 +/- 2.4 -0.9 +/- 2.3 -7.0 24.0 1.1+/- 3.0 Cs-137 Fe-59 H-3 1-131 K-40 La-140 03/16/06 0.4+/-2.5 -5.2 5.5 120.0 +/- 940.0 -4.6 +/- 5.6 -15.0 36.0 -0.7 +/- 5.6 06/14/06 1.1+/-3.9 -6.0 10.0 -440.0 +/- 850.0 0.9+/- 8.2 -3.0 54.0 5.2 +/- 7.7 09/19/06 1.4+/-4.3 -3.5 8.1 10.0 +/- 980.0 0.7 +/- 7.8 54.0 59.0 -1.5 +/- 6.9 12/20/06 0.6+/- 2.6 -6.3 5.4 190.0 +/- 870.0 -2.6 +/- 5.5 -2.0 34.0 2.2 +/- 4.9 Mn-54 Nb-95 Ru-103 Ru-106 Sb-125 Th-228 03/16/06 1.3 +/- 2.5 -4.3 +/- 2.9 -2.9 +/- 2.6 2.0 +/- 24.0 -6.0 6.0 3.0+/- 12.0 06/14/06 -6.8 +/- 4.5 1.1+/- 4.6 -1.5 +/- 4.4 0.0 +/- 39.0 4.0 11.0 -3.0+/- 16.0 09/19/06 0.6+/- 3.4 1.0+/-4.3 -1.5 +/- 4.2 -16.0 +/- 37.0 -6.0 12.0 12.0+/- 13.0 12/20/06 -0.6 +/- 2.4 -0.2 +/- 3.0 1.4 +/- 2.6 4.0 +/- 26.0 -1.9 +/-6.9 -3.5 +/- 9.4 Zn-65 Zr-95 03/16/06 1.4+/- 5.4 2.5 +/- 4.2 06/14/06 -7.5 9.2 2.4 +/- 7.5 09/19/06 8.0+/- 14.0 3.6+/-7.1 12/20/06 8.4 9.9 -0.2 +/- 4.6 72 Ba-140 Be-7 Co-58 Co-60 Cr-51 Cs-134 03/16/06 1.0 +/- 5.2 20.0 20.0 -0.7 +/- 2.5 -1.3 +/- 3.1 -17.0 +/- 23.0 -2.0 +/- 2.5 06/14/06 -0.5 +/- 5.8 -3.0 +/-34.0 -3.1 +/- 3.3 3.7+/- 4.6 8.0 +/- 39.0 1.7 +/- 3.7 09/18/06 -3.2 +/- 4.2 -11.0 18.0 1.0 +/- 2.5 0.7 +/- 2.5 8.0+/- 21.0 -0.2 +/- 2.7 12/01/06 1.7 +/- 4.2 31.0 +/-22.0 -0.6 +/- 2.5 0.4 +/- 2.8 8.0+/- 25.0 0.4 +/- 2.8 12/19/06 4.5 +/- 4.3 30.0 22.0 0.3 +/- 2.7 -0.6 +/- 2.7 -2.0 +/- 24.0 0.1+/- 2.8 Cs-137 Fe-59 H-3 1-131 K-40 La-140 03/16/06 -1.0+/- 2.5 1.9 +/- 5.5 -450.0 +/- 930.0 -2.4+/- 6.1 18.0 +/- 44.0 1.2 +/- 6.0 06/14/06 -0.2 +/- 4.0 3.6+/- 7.5 -310.0 +/- 860.0 1.8 +/- 7.3 13.0 +/- 49.0 -0.6 +/- 6.6 09/18/06 1.6 +/- 2.2 -1.0 +/- 4.8 220.0 +/- 990.0 -0.3 +/- 4.5 -11.0 +/- 35.0 -3.7 +/- 4.8 12/01/06 -1.6+/- 2.6 4.3 +/- 5.7 100.0 +/- 860.0 0.8+/- 5.7 5.0 44.0 1.9 +/- 4.8 12/19/06 0.1 +/- 2.4 -0.6 +/- 4.8 570.0 +/- 880.0 -1.4 +/- 4.9 27.0 49.0 5.2 +/- 4.9 Mn-54 Nb-95 Ru-103 Ru-106 Sb-125 Th-228 03/16/06 1.1 +/- 2.3 -0.6 +/- 3.0 0.6 +/- 2.5 10.0 +/- 24.0 -1.1 +/-6.3 4.0+/-11.0 06/14/06 -0.9 +/- 4.1 0.3 +/- 3.7 -1.2 +/- 3.8 -17.0 +/- 37.0 2.0 10.0 8.0 +/- 17.0 09/18/06 0.5 +/- 2.2 2.7 +/- 2.6 -0.1 +/- 2.7 -9.0 +/- 22.0 0.2 5.8 6.0+/- 11.0 12/01/06 0.4 +/- 2.5 -0.1 +/- 3.1 -1.5 +/- 3.2 9.0 +/- 25.0 -3.2 6.6 4.8 +/- 9.3 12/19/06 -0.5 +/- 2.9 -0.5 +/- 3.1 -3.8 +/- 4.1 -1.0 +/- 24.0 -5.9 6.5 -5.2 +/- 9.9 Zn-65 Zr-95 03/16/06 -1.8 5.6 0.2 +/- 4.4 06/14/06 -11.9 9.6 2.7+/- 5.8 09/18/06 -0.7 7.7 1.6 +/- 4.2 12/01/06 -1.9 6.2 0.2 +/- 5.0 12/19/06 -7.4+/- 6.7 -3.1 +/- 4.6

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 10, Well Water (pCi/L) Page 2 of 4 Location Collection Isotope Date 76-X Ba-140 Be-7 Co-58 ICo-60 Cr-51 Cs-134 06/14/06 2.8 +/- 5.7 30.0 +/- 34.0 -0.7 +/- 3.8 1.0 +/- 4.4 -9.0 +/- 35.0 -0.7 +/- 4.9 09/18/06 2.3 +/- 3.9 -3.0 +/- 20.0 -2.0 +/- 2.4 0.8 +/- 3.0 -7.0 +/- 19.0 -0.9 +/- 2.7 Cs-137 Fe-59 H-3 1-131 K-40 La-140 06/14/06 -0.3 +/- 4.4 -4,0+/- 10.0 -430.0 +/- 850.0 2.0+/- 7.1 -5.0 +/- 54.0 3.3 +/- 6.5 09/18/06 -0.8 +/- 2.3 2.1 +/-5.0 -640.0 +/- 950.0 -0.8 +/- 3.9 -5.0 +/- 41.0 2.6+/- 4.5 Mn-54 Nb-95 Ru-103 Ru-106 Sb-125 Th-228 06/14/06 0.9 +/- 4.3 -6.1 +/- 4.6 -2.6 +/- 4.2 38.0 +/- 39.0 2.0 +/- 10.0 -2.0 +/- 15.0 09/18/06 -0.7 +/- 2.4 1.6 +/- 2.9 -1.3 +/- 2.5 9.0 +/- 20.0 -5.2 +/- 5.8 -1.0+/- 11.0 Zn-65 Zr-95 06/14/06 -14.0 +/- 10.0 -1.1 +/- 7.1 09/18/06 -2.4 +/- 5.5 -1.4 +/- 4.8 77-X Ba-140 Be-7 Co-58 Co-60 Cr-51 Cs-134 12/31/06 I Cs-137 Fe-59 H-3 1-131 K-40 La-140 Mn-54 Nb-95 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 78-X Ba-140 Be-7 Co-58 Co-60 Cr-51 Cs-134 06/14/06 -1.3 +/- 4.0 3.0 +/- 25.0 0.8 +/- 2.4 0.2 +/- 2.7 -5.0 +/- 25.0 -1.4 +/- 3.0 09/18/06 -1.6 +/- 3.5 1.0 +/- 19.0 1.3 +/- 2.2 - 0.6 +/- 2.0 23.0 +/- 20.0 -0.8 +/- 2.4 Cs-137 Fe-59 H-3 1-131 K-40 La-140 06/14/06 0.2 +/- 2.8 -3.2 +/- 5.9 -430.0 +/- 840.0 1.4 +/- 5.5 31.0 +/- 44.0 -1.5 +/- 4.7 09/18/06 -1.4 +/- 2.2 1.1 +/- 4.4 -570.0 +/- 970.0 -3.9 +/- 4.4 7.0 +/- 35.0 -1.8 +/- 4.1 Mn-54 Nb-95 Ru-103 Ru-106 Sb-125 Th-228 06/14/06 -0.7 +/- 2.5 -0.3 +/- 3.1 -4.9 +/- 3.2 10.0 +/- 28.0 5.1 +/- 7.3 1.0+/- 10.0 09/18/06 -0.1 +/- 2.1 -3.7 +/- 2.7 -1.8 +/- 2.3 -5.0 + 21.0 2.7 +/- 5.6 6.4 + 8.4 Zn-65 Zr-95 06/14/06 -5.4 +/- 5.9 -2.1 +/- 4.5 09/18/06 1.6 +/- 9.0 -0.9 +/- 3.8 79

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 10, Well Water (pCi/L) Page 3 of 4 Location Collection Isotope Date 79 Ba-140 Be-7 Co-58 Co-60 Cr-51 Cs-134 06/13/06 0.5 +/- 4.6 6.0 +/- 35.0 -1.8 +/- 3.6 0.8+/- 3.5 -20.0 +/- 32.0 1.2 +/- 4.1 09/18/06 0.0+/-5.1 -20.0 +/- 23.0 -4.2 +/- 3.3 1.5 +/- 3.3 13.0 +/- 22.0 -2.7 +/- 3.2 12/20/06 4.4 +/- 6.8 -5.0 +/- 35.0 -4.5 +/- 4.4 1.5 +/- 5.1 -13.0 +/- 34.0 2.7 +/- 5.0 Cs-137 Fe-59 H-3 1-131 K-40 La-140 06/13/06 0.5 +/- 3.6 -4.8 +/- 7.5 30.0 +/- 860.0 2.7 +/- 7.1 11.0 +/- 56.0 0.6 +/- 5.3 09/18/06 0.7 +/- 2.7 6.5 +/- 6.1 -370.0 +/- 960.0 -1.1 +/- 4.7 19.0 +/- 26.0 0.0 +/- 5.9 12/20/06 -3.3 +/- 4.4 6.0 +/- 9.9 170.0 +/- 880.0 0.5 +/- 6.3 78.0 +/- 61.0 5.1 +/- 7.8 Mn-54 Nb-95 Ru-103 Ru-106 Sb-125 Th-228 06/13/06 0.4 +/- 3.5 -1.6 +/- 4.3 -2.2 +/- 4.2 13.0 +/- 34.0 0.5 +/- 9.0 1.0 +/- 13.0 09/18/06 1.5 +/- 2.7 0.6 +/- 5.2 -2.5 +/- 2.9 -15.0 +/- 23.0 -0.3 +/- 7.4 -9.0 +/- 11.0 12/20/06 1.6 +/- 3.9 -5.1 +/- 5.3 1.7 +/- 4.2 0.0 +/- 37.0 1.0+/- 12.0 -10.0 +/- 16.0 Zn-65 Zr-95 06/13/06 8.0 +/- 15.0 5.1 +/- 6.9 09/18/06 6.0 +/- 13.0 -3.3 +/- 5.3 12/20/06 -2.0 +/- 13.0 3.2 +/- 7.9 80 Ba-140 Be-7 Co-58 Co-60 Cr-51 Cs-134 09/21/06 -1.5 +/- 4.6 -11.0 +/- 22.0 -0.3 +/- 2.5 1.6 +/- 2.3 -4.0 +/- 26.0 1.1 +/- 2.8 12/19/06 -0.3 +/- 3.3 0.0+/- 18.0 -3.1 +/- 2.0 0.8 +/- 2.0 -2.0 +/- 21.0 3.2 +/- 2.2 Cs-137 Fe-59 H-3 1-131 K-40 La-140 09/21/06 -3.2 +/- 2.3 3.6 +/- 5.8 30.0 +/- 980.0 -0.9 +/- 6.4 7.0 +/- 36.0 -1.7 +/- 5.3 12/19/06 3.1 +/-3.4 -2.6 +/- 4.3 -220.0 +/- 880.0 -0.7 +/- 4.1 21.0 26.0 -0.4 +/- 3.7 Mn-54 Nb-95 Ru-103 Ru-106 Sb-125 Th-228 09/21/06 -1.5 +/- 2.4 2.6 +/- 3.1 -0.9 +/- 3.1 6.0 +/- 22.0 -0.4 +/- 6.2 -9.0 10.0 12/19/06 -2.2 +/- 1.9 3.2 +/- 3.6 0.1+/- 2.3 1.0 +/- 19.0 5.3 +/- 5.4 6.2 7.6 Zn-65 Zr-95 09/21/06 6.0 +/- 9.5 -1.6 +/- 4.3 12/19/06 2.2 +/- 8.1 -0.8 +/- 3.5 81 Ba-140 Be-7 Co-58 Co-60 Cr-51 Cs-134 12/19/06 -1.1 +/- 3.3 12.0 +/- 16.0 0.1 +/- 1.9 -0.7 +/- 2.2 1.0 +/- 19.0 0.7 +/- 2.1 Cs-137 Fe-59 H-3 1-131 K-40 La-140 12/19/06 -0.8 +/- 1.9 -0.3 +/- 4.0 0.0 +/- 880.0 -3.9 +/- 4.1 21.0 +/- 33.0 -1.3 +/- 3.8 Mn-54 Nb-95 Ru-103 Ru-106 Sb-125 Th-228 12/19/06 1.6+/- 1.9 -1.3 +/- 3.7 -0.8 +/- 2.1 2.0 +/- 17.0 -2.2 +/- 5.0 8.3 +/- 7.3

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 10, Well Water (pCi/L) Page 4 of 4 Location Collection Isotope Date 81 Zn-65 Zr-95 12/19/06 -0.2 +/- 8.6 -3.9 +/-3.6

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 11, Reservoir Water No data collected during 2006

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 12, Fruits & Vegetables (pCi/g Wet) Page I of 2 Location Collection Sample Type Isotope Date 25 Ba-140 Be-7 Ce-141 Ce-144 Co-58 06/21/06 LETTUCE -0.015 +/- 0.027 0.070 +/- 0.150 -0.004 +/- 0.016 0.056 +/- 0.068 -0.014 +/- 0.017 06/21/06 STRAWBERRIES -0.016 +/- 0.021 0.110 +/- 0.140 0.019 +/- 0.023 0.059 +/- 0.087 0.000 +/- 0.012 09/06/06 APPLES 0.010 +/- 0.024 0.010 +/- 0.110 0.014 +/- 0.018 -0.017 +/- 0.051 0.007 +/- 0.015 09/06/06 KALE 0.003 +/- 0.023 0.090 +/- 0.160 -0.007 +/- 0.023 0.012 +/- 0.088 0.001 +/- 0.014 10/25/06 RHUBARB -0.007 +/- 0.021 0.415 +/- 0.090 -0.019 +/- 0.016 0.010 +/- 0.028 0.003 +/- 0.007 Co-60 Cr-51 Cs-134 Cs-137 Fe-59 06/21/06 LETTUCE -0.006 +/- 0.022 -0.050 +/- 0.110 0.001 +/- 0.016 0.007 +/- 0.015 -0.023 +/- 0.038 06/21/06 STRAWBERRIES 0.012 +/- 0.020 0.110 +/- 0.140 -0.005 +/- 0.017 0.005 +/- 0.016 -0.007 +/- 0.032 09/06/06 APPLES 0.018 +/- 0.017 -0.010 +/- 0.110 0.026 +/- 0.020 0.010 +/- 0.013 -0.011 +/- 0.034 09/06/06 KALE -0.002 +/- 0.024 -0.130 +/- 0.140 0.005 +/- 0.018 -0.003 +/- 0.019 0.003 +/- 0.031 10/25/06 RHUBARB 0.005 +/- 0.005 0.015 +/- 0.075 0.000 +/- 0.011 0.039 +/- 0.009 -0.007 +/- 0.014 1-131 K-40 La-140 Mn-54 Nb-95 06/21/06 LETTUCE 0.014 +/- 0.021 1.810 +/- 0.500 -0.018 +/- 0.031 0.004 +/- 0.018 0.004 +/- 0.017 06/21/06 STRAWBERRIES -0.002 +/- 0.027 0.940 +/- 0.380 -0.019 +/- 0.025 -0.004 +/- 0.014 0.002 +/- 0.015 09/06/06 APPLES -0.001 +/- 0.020 0.690 +/- 0.320 0.012 +/- 0.028 -0.005 +/- 0.017 0.000 +/- 0.017 09/06/06 KALE -0.023 +/- 0.026 3.580 +/- 0.590 0.003 +/- 0.027 -0.003 +/- 0.018 0.003 +/- 0.019 10/25/06 RHUBARB -0.021 +/- 0.034 4.210 +/- 0.210 -0.008 +/- 0.024 -0.001 +/- 0.007 -0.002 +/- 0.009 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 06/21/06 LETTUCE -0.004 +/- 0.014 -0.050 +/- 0.120 0.023 +/- 0.039 -0.039 +/- 0.053 -0.024 +/- 0.040 06/21/06 STRAWBERRIES -0.001 +/- 0.016 0.000 +/- 0.140 0.014 +/- 0.043 0.006 +/- 0.062 0.017 +/- 0.036 09/06/06 APPLES -0.002 +/- 0.014 -0.060 +/- 0.130 -0.014 +/- 0.036 0.002 +/- 0.052 -0.035 +/- 0.034 09/06/06 KALE 0.000 +/- 0.016 0.040 +/- 0.160 -0.023 +/- 0.041 0.006 +/- 0.077 0.043 +/- 0.039 10/25/06 RHUBARB 0.000 +/- 0.008 0.007 +/- 0.064 0.014 +/- 0.016 0.002 +/- 0.040 -0.015 +/- 0.016 Zr-95 06/21/06 LETTUCE -0.015 +/- 0.030 06/21/06 STRAWBERRIES 0.004 +/- 0.025 09/06/06 APPLES -0.017 +/- 0.030 09/06/06 KALE -0.008 +/- 0.030 10/25/06 RHUBARB -0.017 +/- 0.013 26-C Ba-140 Be-7 Ce-141 Ce-144 Co-58 06/21/06 LETTUCE -0.012 +/- 0.019 0.010 +/- 0.120 -0.008 +/- 0.022 -0.086 +/- 0.078 0.003 +/- 0.015 06/21/06 STRAWBERRIES -0.004 +/- 0.032 0.010 +/- 0.130 -0.008 +/- 0.022 0.016 +/- 0.082 0.005 +/- 0.018 09/06/06 PEACHES 0.019 +/- 0.018 0.040 +/- 0.096 -0.004 +/- 0.018 -0.092 +/- 0.066 -0.006 +/- 0.011 09/06/06 SWISS CHARD 0.008 +/- 0.021 0.180 +/- 0.230 -0.001 +/- 0.024 -0.057 +/- 0.082 -0.007 +/- 0.020 Co-60 Cr-51 Cs-134 Cs-137 Fe-59 06/21/06 LETTUCE -0.007 +/- 0.021 0.060 +/- 0.140 -0.009 +/- 0.017 -0.008 +/- 0.016 -0.009 +/- 0.035 06/21/06 STRAWBERRIES -0.002 +/- 0.021 0.060 +/- 0.140 -0.001 +/- 0.019 0.015 +/- 0.018 -0.009 +/- 0.039 09/06/06 PEACHES -0.005 +/- 0.012 0.080 +/- 0.110 0.007 +/- 0.012 0.004 +/- 0.014 0.002 +/- 0.028 09/06/06 SWISS CHARD 0.010 +/- 0.027 -0.100 +/- 0.150 0.006 +/- 0.018 0.008 +/- 0.019 0.008 +/- 0.039 1-131 K-40 La-140 Mn-54 Nb-95 06/21/06 LETTUCE -0.012 +/- 0.027 2.020 +/- 0.450 -0.013 +/- 0.021 0.003 +/- 0.016 -0.001 +/- 0.016 06/21/06 STRAWBERRIES -0.002 +/- 0.031 0.820 +/- 0.430 -0.005 +/- 0.037 -0.002 +/- 0.017 0.019 +/- 0.021 09/06/06 PEACHES 0.004 +/- 0.019 1.650 +/- 0.330 0.022 +/- 0.021 -0.002 +/- 0.013 -0.011 +/- 0.013 09/06/06 SWISS CHARD -0.003 +/- 0.025 4.740 +/- 0.750 0.009 +/- 0.025 0.013 +/- 0.019 0.007 +/- 0.018 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 06/21/06 LETTUCE 0.002 +/- 0.019 0.130 +/- 0.140 -0.011 +/- 0.040 0.023 +/- 0.063 0.027 +/- 0.039 06/21/06 STRAWBERRIES 0.006 +/- 0.017 0.000 +/- 0.140 0.038 +/- 0.044 0.013 +/- 0.081 -0.009 +/- 0.037

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 12, Fruits & Vegetables (pCi/g Wet) Page 2 of 2 Location Collection Sample Type Isotope Date 26-C Ru-103 Ru-106 Sb-125 Th-228 Zn-65 09/06/06 PEACHES 0.002 +/- 0.012 0.090 +/- 0.130 -0.001 +/- 0.032 0.010 +/- 0.047 -0.028 +/- 0.034 09/06/06 SWISS CHARD -0.017 +/- 0.016 0.120 +/- 0.160 -0.006 +/- 0.046 0.000 +/- 0.069 -0.030 +/- 0.053 Zr-95 06/21/06 LETTUCE -0.010 +/- 0.027 06/21/06 STRAWBERRIES 0.000 +/- 0.034 09/06/06 PEACHES -0.011 +/- 0.024 09/06/06 SWISS CHARD -0.007 +/- 0.036

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 13, Broadleaf Vegetation (pCi/g Wet) Page 1 of 3 Location Collection Isotope Date 01 Ba-140 Be-7 Ce-141 Ce-144 Co-58 Co-60 04/13/06 H 05/18/06 0.011 +/- 0.014 1.460 +/- 0.270 0.019 +/- 0.020 0.012 +/- 0.076 -0.001 +/- 0.016 -0.001 +/- 0.019 06/21/06 -0.075 +/- 0.079 0.860 +/- 0.390 0.020 +/- 0.041 -0.061 +/- 0.099 0.017 +/- 0.036 0.008 +/- 0.034 07/26/06 0.023 +/- 0.042 0.900 +/- 0.310 -0.014 +/- 0.035 0.050 +/- 0.110 0.000 +/- 0.021 -0.012 +/- 0.023 08/22/06 -0.019 +/- 0.063 0.710 +/- 0.350 -0.020 +/- 0.033 0.090 +/- 0.110 -0.001 +/- 0.025 0.002 +/- 0.029 09/26/06 0.020 +/- 0.064 2.630 +/- 0.530 -0.032 +/- 0.046 -0.010 +/- 0.120 0.007 +/- 0.026 -0.014 +/- 0.020 10/17/06 0.062 +/- 0.062 2.470 +/- 0.440 -0.059 +/- 0.037 -0.020 +/- 0.110 -0.002 +/- 0.024 0.007 +/- 0.022 11/07/06 -0.005 +/- 0.025 0.870 +/- 0.160 -0.028 +/- 0.024 -0.020 +/- 0.048 -0.005 +/- 0.013 0.008 +/- 0.015 Cr-51 Cs-134 Cs-137 Fe-59 1-131 K-40 05/18/06 0.140 +/- 0.130 0.003 +/- 0.020 0.011 +/- 0.016 0.020 +/- 0.031 -0.013 +/- 0.020 3.530 +/- 0.580 06/21/06 0.060 +/- 0.260 0.000 +/- 0.027 0.014 +/- 0.031 0.076 +/- 0.080 0.060 +/- 0.120 3.960 +/- 0.970 07/26/06 -0.040 +/- 0.200 0.011 +/- 0.024 -0.008 +/- 0.023 0.048 +/- 0.051 0.028 +/- 0.062 3.950 +/- 0.640 08/22/06 0.070 +/- 0.250 -0.007 +/- 0.029 -0.013 +/- 0.026 -0.010 +/- 0.067 0.056 +/- 0.084 4.150 +/- 0.740 09/26/06 0.100 +/- 0.310 0.013 +/- 0.028 0.020 +/- 0.030 0.033 +/- 0.071 0.150 +/- 0.160 3.460 +/- 0.720 10/17/06 -0.160 +/- 0.300 -0.009 +/- 0.024 -0.001 +/- 0.025 -0.027 +/- 0.063 0.000 +/- 0.015 3.730 +/- 0.650 11/07/06 0.071 +/- 0.098 0.009 +/- 0.014 0.010 +/- 0.012 -0.018 +/- 0.030 -0.008 +/- 0.030 3.640 +/- 0.370 La-140 Mn-54 Nb-95 Ru-103 Ru-106 Sb-125 05/18/06 0.013 +/- 0.016 0.003 +/- 0.015 0.009 +/- 0.017 -0.008 +/- 0.017 -0.070 +/- 0.120 0.028 +/- 0.037 06/21/06 -0.086 +/- 0.091 0.035 +/- 0.032 -0.003 +/- 0.043 0.009 +/- 0.034 -0.140 +/- 0.200 -0.045 +/- 0.064 07/26/06 0.027 +/- 0.049 -0.004 +/- 0.020 0.000 +/- 0.029 -0.021 +/- 0.023 0.050 +/- 0.190 --0.049 +/- 0.051 08/22/06 -0.022 +/- 0.073 -0.012 +/- 0.026 -0.019 +/- 0.026 0.006 +/- 0.025 0.250 +/- 0.210 -0.013 +/- 0.059 09/26/06 0.023 +/- 0.074 0.002 +/- 0.026 -0.020 +/- 0.036 -0.005 +/- 0.031 -0.240 +/- 0.250 0.000 +/- 0.062 10/17/06 0.072 +/- 0.071 -0.005 +/- 0.023 -0.023 +/- 0.029 0.003 +/- 0.026 0.010 +/- 0.220 -0.020 +/- 0.061 11/07/06 -0.006 +/- 0.029 0.005 +/- 0.013 -0.001 +/- 0.016 -0.002 +/- 0.012 -0.020 +/- 0.100 0.016 +/- 0.028 Th-228 Zn-65 Zr-95 05/18/06 0.017 +/- 0.063 -0.002 +/- 0.038 -0.032 +/- 0.029 06/21/06 0.080 +/- 0.110 -0.008 +/- 0.060 0.016 +/- 0.062 07/26/06 0.041 +/- 0.079 0.024 +/- 0.089 0.003 +/- 0.040 08/22/06 0.070 +/- 0.130 -0.022 +/- 0.053 -0.017 +/- 0.045 09/26/06 0.060 +/- 0.110 -0.089 +/- 0.085 0.013 +/- 0.052 10/17/06 0.080 +/- 0.093 -0.012 +/- 0.059 0.003 +/- 0.042 11/07/06 0.052 +/- 0.066 -0.020 +/- 0.029 0.008 +/- 0.024 10 Ba-140 Be-7 Ce-141 Ce-144 Co-58 Co-60 04/13/06 H 05/18/06 0.002 +/- 0.030 0.860 +/- 0.290 -0.010 +/- 0.021 -0.008 +/- 0.083 -0.008 +/- 0.019 -0.017 +/- 0.020 06/21/06 -0.018 +/- 0.057 0.300 +/- 0.380 -0.017 +/- 0.051 0.070 +/- 0.150 -0.008 +/- 0.029 -0.015 +/- 0.030 07/26/06 0.025 +/- 0.044 0.320 +/- 0.290 0.006 +/- 0.032 -0.010 +/- 0.099 -0.004 +/- 0.022 -0.001 +/- 0.030 08/22/06 -0.014 +/- 0.046 0.320 +/- 0.270 0.003 +/- 0.028 0.001 +/- 0.090 -0.014 +/- 0.027 -0.024 +/- 0.037 09/26/06 -0.039 +/- 0.052 1.520 +/- 0.200 -0.017 +/- 0.029 -0.016 +/- 0.045 0.005 +/- 0.012 0.009 +/- 0.012 10/17/06 0.160+/- 0.160 1.570 +/- 0.280 0.018 +/- 0.026 0.016 +/- 0.074 -0.008 +/- 0.020 -0.014 +/- 0.019 11/07/06 0.000 +/- 0.051 1.000 +/- 0.270 -0.014 +/- 0.024 -0.008 +/- 0.062 0.002 +/- 0.022 0.011 +/- 0.022 Cr-51 Cs-134 Cs-137 Fe-59 1-131 K-40 05/18/06 0.030 +/- 0.150 0.000 +/- 0.022 0.021 +/- 0.023 -0.025 +/- 0.043 0.011 +/- 0.025 3.010 +/- 0.800 06/21/06 0.130 +/- 0.360 0.001 +/- 0.030 0.007 +/- 0.031 -0.029 +/- 0.072 0.040 +/- 0.140 3.760 +/- 0.970 07/26/06 -0.100 +/- 0.230 -0.006 +/- 0.026 0.004 +/- 0.026 0.026 +/- 0.048 -0.056 +/- 0.077 3.590 +/- 0.790 08/22/06 0.000 +/- 0.250 -0.004 +/- 0.027 0.009 +/- 0.026 0.017 +/- 0.062 0.000 +/- 0.078 3.990 +/- 0.770

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 13, Broadleaf Vegetation (pCi/g Wet) Page 2 of 3 Location Collection Isotope Date 10 Cr-51 Cs-134 Cs-137 Fe-59 1-131 K-40 09/26/06 -0.270 +/- 0.200 0.008 +/- 0.012 0.012 +/- 0.011 0.006 +/- 0.033 -0.060 +/- 0.094 4.030 +/- 0.370 10/17/06 -0.110+/- 0.200 -0.019 +/- 0.017 0.003 +/- 0.019 -0.010 +/- 0.046 0.010 +/- 0.023 3.360 +/- 0.490 11/07/06 0.130 +/- 0.160 -0.015 +/- 0.022 0.020 +/- 0.021 0.012 +/- 0.052 0.025 +/- 0.045 3.200 +/- 0.610 La-140 Mn-54 Nb-95 Ru-103 Ru-106 Sb-125 05/18/06 0.003 +/- 0.034 -0.001 +/- 0.022 -0.006 +/- 0.025 0.013 +/- 0.020 0.040 +/- 0.210 -0.027 +/- 0.046 06/21/06 -0.021 +/- 0.065 0.000 +/- 0.035 0.039 +/- 0.043 -0.017 +/- 0.027 -0.030 +/- 0.260 -0.060 +/- 0.072 07/26/06 0.029 +/- 0.051 0.015 +/- 0.025 -0.004 +/- 0.024 0.015 +/- 0.023 -0.080 +/- 0.240 -0.013 +/- 0.052 08/22/06 -0.017 +/- 0.052 0.017 +/- 0.025 -0.027 + 0.028 0.000 +/- 0.025 -0.140 +/- 0.250 -0.007 +/- 0.053 09/26/06 -0.045 +/- 0.060 0.001 +/- 0.011 0.003 +/- 0.017 -0.010 +/- 0.015 0.000 +/- 0.110 -0.006 +/- 0.025 10/17/06 0.013 +/- 0.095 -0.029 +/- 0.018 0.008 +/- 0.027 0.017 +/- 0.019 0.150 +/- 0.150 -0.001 +/- 0.045 11/07/06 0.000 +/- 0.059 0.005 +/- 0.019 0.003 +/- 0.026 0.003 +/- 0.016 0.060 +/- 0.170 0.028 +/- 0.042 Th-228 Zn-65 Zr-95 05/18/06 -0.001 + 0.099 -0.026 +/- 0.055 -0.023 + 0.047 06/21/06 0.011 +/- 0.092 -0.005 +/- 0.056 0.022 +/- 0.060 07/26/06 0.020 +/- 0.110 0.000 +/- 0.066 0.022 +/- 0.050 08/22/06 -0.010 +/- 0.100 -0.031 +/- 0.064 0.034 +/- 0.045 09/26/06 0.059 +/- 0.043 0.014 +/- 0.027 -0.003 +/- 0.023 10/17/06 0.089 +/- 0.064 -0.037 +/- 0.038 -0.006 +/- 0.025 11/07/06 0.050 +/- 0.110 0.012 +/- 0.045 -0.031 +/- 0.035 17 Ba-140 Be-7 Ce-141 Ce-144 Co-58 Co-60 04/13/06 H 05/18/06 0.002 +/- 0.024 1.190 +/- 0.280 -0.002 +/- 0.021 -0.055 +/- 0.066 0.001 +/- 0.018 0.008 +/- 0.027 06/21/06 0.060 +/- 0.110 0.780 +/- 0.400 -0.027 +/- 0.041 -0.020 +/- 0.120 -0.009 +/- 0.043 0.004 +/- 0.039 07/26/06 -0.009 +/- 0.040 0.860 +/- 0.480 0.000 +/- 0.042 0.010 +/- 0.140 0.012 +/- 0.032 -0.002 +/- 0.037 08/22/06 -0.048 + 0.071 1.000 +/- 0.350 -0.004 +/- 0.035 0.020 +/- 0.079 0.012 +/- 0.026 0.008 +/- 0.029 09/26/06 0.004 +/- 0.034 2.490 +/- 0.200 0.015 +/- 0.018 -0.004 +/- 0.043 -0.003 +/- 0.010 -0.001 +/- 0.009 10/17/06 -0.021 +/- 0.076 1.790 +/- 0.290 0.005 +/- 0.027 0.063 +/- 0.059 -0.013 +/- 0.023 0.015 +/- 0.021 11/07/06 -0.005 +/- 0.036 6.110 +/- 0.340 0.009 +/- 0.024 -0.026 +/- 0.082 -0.007 +/- 0.017 0.010 +/- 0.017 Cr-51 Cs-134 Cs-137 Fe-59 1-131 K-40 05/18/06 0.000 +/- 0.130 0.003 +/- 0.021 0.003 +/- 0.020 0.014 +/- 0.035 0.013 +/- 0.021 3.990 +/- 0.780 06/21/06 -0.120 +/- 0.310 0.013 +/- 0.032 0.009 +/- 0.032 0.019 +/- 0.085 -0.050 +/- 0.130 3.010+/- 0.810 07/26/06 -0.050 +/- 0.300 -0.014 +/- 0.028 -0.023 +/- 0.038 -0.049 +/- 0.073 -0.016 +/- 0.092 2.460 +/- 0.740 08/22/06 0.000 +/- 0.220 -0.007 +/- 0.030 0.015 +/- 0.027 -0.006 +/- 0.066 0.028 +/- 0.071 3.850 +/- 0.780 09/26/06 0.080 +/- 0.130 0.011 +/- 0.010 -0.003 +/- 0.008 0.008 +/- 0.025 0.030 +/- 0.079 4.000 +/- 0.290 10/17/06 0.030 +/- 0.190 -0.008 +/- 0.022 0.023 +/- 0.018 0.024 +/- 0.047 -0.008 +/- 0.003 3.720 +/- 0.490 11/07/06 0.010 +/- 0.180 0.004 +/- 0.017 0.182 +/- 0.028 0.000 +/- 0.037 -0.002 +/- 0.054 2.080 +/- 0.340 La-140 Mn-54 Nb-95 Ru-103 Ru-106 Sb-125 05/18/06 0.002 +/- 0.028 0.003 +/- 0.022 -0.002 +/- 0.022 0.006 +/- 0.019 -0.040 +/- 0.170 0.013 +/- 0.045 06/21/06 0.070 +/- 0.120 -0.007 +/- 0.027 0.006 +/- 0.043 0.018 +/- 0.035 -0.090 +/- 0.280 0.028 +/- 0.076 07/26/06 -0.010 +/- 0.046 0.005 +/- 0.036 -0.019 +/- 0.034 0.000 +/- 0.032 0.030 +/- 0.290 -0.010 +/- 0.075 08/22/06 -0.055 +/- 0.082 -0.013 +/- 0.027 -0.004 +/- 0.039 -0.005 +/- 0.028 0.050 +/- 0.240 -0.044 +/- 0.062 09/26/06 0.004 +/- 0.040 -0.001 +/- 0.009 0.012 +/- 0.013 0.001 +/- 0.012 -0.049 +/- 0.090 0.009 +/- 0.021 10/17/06 -0.024 +/- 0.087 0.004 +/- 0.019 0.005 +/- 0.025 0.010 +/- 0.022 0.030 +/- 0.140 0.045 +/- 0.044 11/07/06 -0.005 +/- 0.041 -0.001 +/- 0.016 0.003 +/- 0.020 -0.002 +/- 0.018 0.000 +/- 0.160 -0.028 +/- 0.043

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 13, Broadleaf Vegetation (pCi/g Wet) Page 3 of: 3 Location Collection Isotope Date 17 Th-228 Zn-65 Zr-95 05/18/06 0.072 +/- 0.089 -0.019 +/- 0.054 -0.011 +/- 0.036 06/21/06 0.090 +/- 0.150 -0.033 +/- 0.062 -0.051 +/- 0.062 07/26/06 0.370 +/- 0.190 -0.092 +/- 0.085 0.022 +/- 0.059 08/22/06 0.240 :k 0.110 -0.065 +/- 0.069 0.026 +/- 0.059 09/26/06 0.043 +/- 0.046 -0.003 +/- 0.021 0.008 +/- 0.018 10/17/06 0.052 +/- 0.098 0.010 +/- 0.046 -0.004 +/- 0.039 11/07/06 0.134 +/- 0.082 0.021 +/- 0.060 0.009 +/- 0.029

Dominion Nuclear Connecticut. Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 14, Sea Water (pCi/L) Page 1 of 2 Location Collection Isotope Date 32 Ba-140 Be-7 Co-58 Co-60 Cr-51 Cs-134 01/31/06 0.0+/- 4.8 18.0 +/-30.0 -2.3 +/- 3.5 2.5 +/- 3.3 -13.0 32.0 -1.3 +/- 3.9 02/28/06 0.9 +/-5.6 -8.0 +/-26.0 0.4 +/- 3.3 1.5 +/- 3.6 -5.0 31.0 -3.3 +/- 4.1 03/28/06 3.2 +/-6.7 -7.0 +/-30.0 -2.8 +/- 3.7 2.5 +/- 4.3 7.0 +/-28.0 -0.7 +/- 4.4 04/25/06 0.0+/-5.9 -18.0 +/-40.0 -4.1 +/- 4.0 -3.2 +/- 4.1 21.0 36.0 0.3 +/- 3.8 05/30/06 -1.3 +/-5.8 -29.0 32.0 0.6 +/- 4.0 0.8 +/- 4.4 31.0 34.0 0.3 +/- 4.0 06/27/06 0.0 +/- 6.0 14.0 25.0 3.0 +/- 3.2 -0.7 +/- 3.2 -2.0 29.0 0.5 +/- 2.9 07/25/06 -0.9 +/-5.0 -10.0 19.0 1.1 +/- 2.5 0.5 +/-2.1 1.0 24.0 -0.9 +/- 2.0 08/29/06 -1.9 +/-5.0 4.0 +/- 22.0 -1.9 +/- 2.5 -0.7 +/- 2.5 -8.0 25.0 -1.7 +/- 2.9 09/26/06 -1.9 +/-3.6 -3.0 +/- 20.0 0.6 +/- 2.2 0.1+/- 2.4 -11.0 21.0 0.1 +/- 2.5 10/31/06 -2.9 +/- 3.7 10.0 +/- 25.0 -0.7 +/- 3.0 2.0 +/- 3.1 -5.0 26.0 -2.2 +/- 3.5 11/28/06 -3.5 +/- 6.0 14.0 +/- 27.0 -2.5 +/- 3.2 4.6 +/- 4.2 31.0 32.0 -0.1+/- 3.6 12/26/06 2.1 +/- 5.5 7.0 +/- 25.0 0.7 +/- 3.1 2.3 +/- 3.9 14.0 +/- 25.0 -0.3 +/- 3.6 Cs-137 Fe-59 H-3 1-131 K40 La-140 01/31/06 -2.1 +/- 3.1 1.9 +/- 7.4 50.0 120.0 0.3 +/- 6.3 274.0 +/- 72.0 0.0 +/- 5.5 02/28/06 -2.2 +/- 3.4 -3.8 +/- 7.8 540.0 +/- 160.0 -3.4 +/- 6.2 229.0 +/- 78.0 1.0 +/- 6.4 03/28/06 -0.4 +/- 3.5 3.5 +/- 7.3 770.0 +/- 190.0 -3.3 +/- 6.4 263.0 +/- 88.0 3.7 +/- 7.7 04/25/06 0.6+/- 3.6 1.9 +/- 9.5 550.0 +/- 180.0 -4.4 +/- 6.9 316.0 +/- 82.0 0.0 +/- 6.8 05/30/06 -2.3 +/- 3.5 0.9 +/- 8.2 190.0 170.0 -2.2 +/- 7.5 288.0 +/- 88.0 -1.5 +/- 6.7 06/27/06 -1.1+/-2.4 1.5 +/- 7.0 90.0 +/- 170.0 0.0+/- 8.0 226.0 +/- 72.0 0.0 +/- 6.9 07/25/06 0.0 +/- 2.0 2.1+/-4.9 50.0 +/- 180.0 0.7 +/- 8.0 259.0 +/- 53.0 -1.0 +/- 5.8 08/29/06 2.9+/- 2.6 3.5 +/- 5.7 350.0 +/- 180.0 -4.2 +/- 5.6 338.0 +/- 60.0 -2.2 +/- 5.8 09/26/06 0.2 +/- 2.1 0.6 +/- 4.4 190.0 +/- 990.0 -0.1+/- 5.1 268.0 +/- 48.0 -2.2+/-4.1 10/31/06 0.0 +/- 2.7 -0.9 +/- 6.2 270.0 +/- 900.0 5.0 +/- 5.4 299.0 +/- 63.0 -3.3 +/- 4.2 11/28/06 -1.3 +/- 3.7 1.2 +/- 7.6 290.0 +/- 180.0 -1.4 +/- 6.2 330.0 +/- 86.0 -4.1+/- 6.9 12/26/06 -1.4+/- 3.1 1.7 +/- 7.3 550.0 +/- 170.0 0.9 +/- 5.1 236.0 +/- 75.0 2.5 +/- 6.3 Mn-54 Nb-95 Ru-103 Ru-106 Sb-125 Th-228 01/31/06 3.7 +/- 3.0 -2.8 +/- 3.7 -0.1 +/- 3.5 5.0 +/- 33.0 -0.8 +/- 9.1 -13.0 12.0 02/28/06 -0.6+/- 3.3 0.0 +/- 4.2 -0.9 +/- 3.8 -10.0 +/- 33.0 -0.8+/- 9.0 1.0+/-12.0 03/28/06 2.3 +/- 3.6 0.0 +/- 4.6 1.1 +/-4.2 20.0 +/- 30.0 -0.4 +/- 9.7 5.0 +/- 14.0 04/25/06 -1.2 +/- 3.8 0.3 +/- 4.8 -0.8 +/- 4.4 11.0 +/- 32.0 4.8 +/- 9.5 -4.0+/- 15.0 05/30/06 -1.7 +/- 4.1 -1.7+/- 5.1 -3.1+/- 4.6 -7.0 +/- 40.0 -4.6 +/- 8.8 1.0 14.0 06/27/06 -0.7 +/- 2.7 -1.7+/- 3.3 -3.5 +/- 3.3 0.0+/-24.0 -2.7 +/- 7.1 -4.2 9.5 07/25/06 1.0+/- 1.9 1.8+/- 2.9 -1.8 +/- 2.7 5.0 +/- 20.0 2.3 +/- 5.2 -3.4 7.1 08/29/06 -0.3 +/- 2.4 0.1 +/- 2.9 -0.2 +/- 2.6 -19.0 +/- 24.0 0.3 +/- 7.2 3.0+/- 10.0 09/26/06 -1.3 +/- 2.1 0.3 +/- 2.5 -2.4 +/- 2.5 -12.0+/- 19.0 5.4 +/- 5.6 -7.7 +/-8.5 10/31/06 -0.1 +/-2.9 -1.2 +/- 3.1 -1.0 +/- 3.3 39.0 +/- 28.0 4.9+/- 7.4 8.0 10.0 11/28/06 -3.7 +/- 3.1 -0.7 +/- 3.7 -0.6 +/- 3.4 -21.0 +/- 34.0 -0.6+/- 8.7 12.0 13.0 12/26/06 -0.4 +/- 3.2 -0.2 +/- 4.0 -1.7 +/- 3.1 -6.0 +/- 27.0 -4.9 +/- 7.4 3.0 12.0 Zn-65 Zr-95 01/31/06 -3.7 +/- 7.5 -0.7+/- 6.1 02/28/06 13.0+/- 13.0 3.2+/- 6.1 03/28/06 -3.0 +/- 7.7 -0.4 +/- 7.2 04/25/06 4.0+/- 16.0 1.7 +/- 6.3 05/30/06 2.0+/- 10.0 3.6+/- 6.9 06/27/06 2.8+/- 6.3 5.8 +/- 5.4 07/25/06 -3.0 +/- 5.4 0.5 +/- 4.1 08/29/06 -4.4 +/- 5.8 -0.7 +/- 4.2 09/26/06 -5.1 +/- 6.7 1.3 +/- 3.8 10/31/06 0.0 +/- 6.7 -1.3 +/- 4.2 11/28/06 -4.3 +/- 8.0 -1.3 +/- 5.9 12/26/06 -3.0 +/- 7.0 0.5 +/- 5.4

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 14, Sea Water (pCi/L) Page 2 of 2 Location Collection Isotope Date 37-C Ba-140 Be-7 Co-58 Co-60 Cr-51 Cs-134 02/28/06 0.2 +/- 5.3 -16.0 +/- 28.0 -2.6 +/- 3.2 -2.1 +/- 3.4 6.0 +/-33.0 1.1+/- 3.9 06/06/06 -3.2 +/- 4.6 -10.0 +/- 21.0 -1.9 +/- 2.6 0.0+/- 3.7 13.0 +/-23.0 -3.0 +/- 2.8 09/05/06 1.4+/- 5.2 -5.0+/-21.0 -2.8 +/- 2.8 -1.9 +/- 3.2 -1.0 +/-24.0 3.6 +/- 3.0 12/05/06 3.5 +/- 4.2 22.0 + 23.0 0.6 +/- 2.4 2.1 +/-2.5 5.0 +/-23.0 0.5 +/- 2.7 Cs-137 Fe-59 H-3 1-131 K40 La-140 02/28/06 2.1 +/- 3.2 3.3 +/- 6.1 -70.0+/- 150.0 -7.2 +/- 6.2 209.0 +/- 66.0 0.2 +/- 6.1 06/06/06 1.2 +/- 2.9 -0.7 +/- 6.6 -300.0 +/- 860.0 0.3 +/- 4.9 262.0 +/- 66.0 -3.7 +/- 5.2 09/05/06 -0.7 +/- 3.1 -0.4 +/- 6.8 -320.0 +/- 770.0 -2.2 +/- 4.7 276.0 +/- 64.0 1.6 +/- 5.9 12/05/06 -0.9 +/- 2.4 -4.4+/-5.5 310.0+/- 860.0 -3.7+/- 5.2 235.0 +/- 50.0 4.0 +/- 4.9 Mn-54 Nb-95 Ru-103 Ru-106 Sb-125 Th-228 02/28/06 -0.6 +/- 3.3 0.2+/-3.5 -0.5 +/- 3.3 11.0 +/- 29.0 -1.8 +/- 9.3 1.0+/- 11.0 06/06/06 -2.3 +/- 2.6 2.9+/-2.8 -1.7 +/- 2.6 18.0 +/- 25.0 -7.1 +/- 6.4 13.0+/- 12.0 09/05/06 -0.7 +/- 2.6 -2.1 +/- 3.2 0.1 +/- 2.8 -1.0+/- 25.0 3.4 +/- 7.3 6.0+/- 13.0 12/05/06 2.3 +/- 2.3 -1.1 +/- 2.7 -1.6 +/- 2.8 -2.0 +/- 23.0 3.6 +/- 6.0 2.0+/- 11.0 Zn-65 Zr-95 02/28/06 -7.5 +/- 8.3 0.3 +/- 5.3 06/06/06 -4.7 +/- 6.9 -1.8+/- 4.6 09/05/06 1.8 +/- 8.9 2.7 +/- 4.9 12/05/06 -5.0 +/- 6.1 -0.2 +/- 4.2

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 15, Bottom Sediment (pCi/g Dry) Page 1 of 3 Location Collection Isotope Date Date 29 Ag-il0m Be-7 Co-58 Co-60 Cr-51 Cs-134 04/26/06 -0.011 +/- 0.029 0.010 +/- 0.180 -0.016+/- 0.018 0.006 +/- 0.021 -0.150 +/- 0.220 0.047 +/- 0.089 10/17/06 -0.005 +/- 0.036 0.050 +/- 0.260 0.010 + 0.031 0.024 +/- 0.029 -0.100 +/- 0.340 0.011 +/- 0.044 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 04/26/06 0.028 +/- 0.028 -0.041 +/- 0.053 -0.005 +/- 0.053 13.880 +/- 0.920 -0.008 +/- 0.024 0.000 +/- 0.027 10/17/06 0.011 +/- 0.029 -0.030 +/- 0.073 -0.010 +/- 0.170 16.930 +/- 0.970 -0.004 +/- 0.028 -0.012 +/- 0.043 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 04/26/06 0.016 +/- 0.021 -0.040 +/- 0.190 -0.014 +/- 0.058 1.043 +/- 0.096 -0.070 +/- 0.110 0.041 +/- 0.040 10/17/06 -0.007 +/- 0.036 0.040 +/- 0.250 -0.004 +/- 0.070 1.200 +/- 0.110 -0.080 +/- 0.120 -0.010 +/- 0.058 31 Ag-110m Be-7 Co-58 Co-60 Cr-51 Cs-134 04/27/06 -0.032 +/- 0.039 0.260 + 0.280 -0.014 +/- 0.026 -0.009 +/- 0.030 0.010 +/- 0.350 0.019 +/- 0.029 11/07/06 -0.004 +/- 0.033 0.100 +/- 0.230 -0.017 +/- 0.026 -0.005 +/- 0.021 0.060 +/- 0.260 0.005 +/- 0.024 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 04/27/06 0.026 +/- 0.034 -0.031 +/- 0.064 0.064 +/- 0.094 11.100 +/- 0.900 -0.002 +/- 0.049 -0.005 +/- 0.040 11/07/06 -0.003 +/- 0.026 0.017 +/- 0.064 0.022 +/- 0.077 17.700 +/- 1.100 -0.007 +/- 0.028 -0.002 +/- 0.034 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 04/27/06 0.011 +/- 0.036 0.040 +/- 0.290 -0.025 +/- 0.079 3.320 +/- 0.160 0.060 +/- 0.130 -0.024 +/- 0.076 11/07/06 0.006 +/- 0.029 -0.060 +/- 0.240 -0.003 +/- 0.060 0.870 +/- 0.110 0.070 +/- 0.100 0.048 +/- 0.051 32 Ag-110m Be-7 Co-58 Co-60 Cr-51 Cs-134 04/26/06 -0.027 +/- 0.033 0.000 +/- 0.220 0.011 +/- 0.027 -0.011 +/- 0.032 0.000 +/- 0.240 -0.008 +/- 0.021 10/17/06 0.018 +/- 0.055 0.050 +/- 0.390 -0.023 +/- 0.036 0.010 +/- 0.042 0.220 +/- 0.460 0.016 +/- 0.039 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 04/26/06 0.004 +/- 0.028 0.038 +/- 0.071 0.004 +/- 0.054 12.700 +/- 1.300 0.013 +/- 0.028 0.007 +/- 0.042 10/17/06 -0.029 +/- 0.042 0.000 +/- 0.110 -0.130 +/- 0.350 14.600 +/- 1.400 -0.005 +/- 0.035 -0.052 +/- 0.060 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 04/26/06 -0.009 +/- 0.027 0.060 +/- 0.220 0.007 +/- 0.072 0.660 +/- 0.130 -0.020 +/- 0.140 -0.024 +/- 0.049 10/17/06 -0.043 +/- 0.044 -0.160 +/- 0.350 0.011 +/- 0.087 0.950 +/- 0.160 0.050 +/- 0.170 0.019 +/- 0.075 33 Ag-110m Be-7 Co-58 Co-60 Cr-51 Cs-134 04/26/06 0.016+/- 0.039 0.050 +/- 0.210 0.008 +/- 0.026 -0.009 +/- 0.025 0.030 +/- 0.240 -0.009 +/- 0.036 11/03/06 -0.008 +/- 0.031 0.160 +/- 0.230 -0.011 +/- 0.025 -0.003 +/- 0.022 -0.100 +/- 0.320 0.021 +/- 0.027 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 04/26/06 0.000 +/- 0.032 -0.039 +/- 0.065 0.003 +/- 0.062 16.700 +/- 1.400 -0.015 +/- 0.021 0.011 +/- 0.032 11/03/06 -0.007 +/- 0.026 -0.032 +/- 0.059 0.090 +/- 0.100 12.130 +/- 0.880 0.009 +/- 0.024 -0.001 +/- 0.043

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 15, Bottom Sediment (pCi/g Dry) Page 2 of 3 Location Collection Isotope Date 33 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 04/26/06 0.006 +/- 0.024 -0.070 +/- 0.240 0.086 +/- 0.061 0.340 +/- 0.100 -0.033 +/- 0.081 0.003 +/- 0.038 11/03/06 -0.010 +/- 0.026 0.030 +/- 0.190 0.020 +/- 0.062 0.880 +/- 0.100 -0.060 +/- 0.110 -0.012 +/- 0.048 34 Ag-il0m Be-7 Co-58 Co-60 Cr-51 Cs-134 04/26/06 -0.022 +/- 0.031 0.090 +/- 0.170 0.007 +/- 0.024 0.002 +/- 0.026 -0.050 +/- 0.160 -0.003 +/- 0.018 11/03/06 -0.007 +/- 0.031 0.230 +/- 0.210 -0.038 +/- 0.031 0.008 +/- 0.027 0.080 +/- 0.230 0.003 +/- 0.020 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 04/26/06 0.025 +/- 0.024 -0.033 +/- 0.059 0.054 +/- 0.046 15.100 +/- 1.300 -0.021 +/- 0.024 -0.011 +/- 0.031 11/03/06 0.011 +/- 0.021 -0.011 +/- 0.081 -0.028 +/- 0.095 15.200 +/- 1.300 0.028 +/- 0.028 -0.017 +/- 0.036 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 04/26/06 -0.005 +/- 0.016 -0.100 +/- 0.170 -0.033 +/- 0.051 0.086 +/- 0.096 -0.018 +/- 0.066 -0.011 +/- 0.036 11/03/06 -0.027 +/- 0.027 -0.050 +/- 0.180 -0.021 +/- 0.058 0.100 +/- 0.140 0.030 +/- 0.120 0.007 +/- 0.044 35-X Ag-110m Be-7 Co-58 Co-60 Cr-51 Cs-134 04/26/06 0.010 +/- 0.040 0.270 +/- 0.260 -0.025 +/- 0.034 0.013 +/- 0.038 0.130 +/- 0.310 0.031 +/- 0.030 10/17/06 0.000 +/- 0.050 0.320 +/- 0.380 -0.014 +/- 0.040 -0.002 +/- 0.038 0.180 +/- 0.520 0.026 +/- 0.038 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 04/26/06 0.041 +/- 0.040 0.031 +/- 0.079 0.019 +/- 0.077 11.800 +/- 1.400 0.026 +/- 0.034 -0.039 +/- 0.046 10/17/06 0.011 +/-0.040 0.030 +/- 0.110 0.210 +/- 0.360 16.200 +/- 1.400 0.000 +/- 0.038 0.007 +/- 0.069 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 04/26/06 0.024 +/- 0.033 0.020 +/- 0.330 -0.052 +/- 0.081 0.770 +/- 0.140 -0.040 +/- 0.160 -0.002 +/- 0.052 10/17/06 0.007 +/- 0.054 -0.060 +/- 0.350 -0.078 +/- 0.086 0.870 +/- 0.160 -0.050 +/- 0.180 0.036 +/- 0.078 37-C Ag-il0m Be-7 Co-58 Co-60 Cr-51 Cs-134 04/27/06 -0.034 +/- 0.028 0.100 +/- 0.180 0.005 +/- 0.023 0.001 +/- 0.026 0.050 +/- 0.170 0.010 +/- 0.017 11/07/06 -0.003 +/- 0.041 -0.060 +/- 0.210 0.036 +/- 0.030 -0.012 +/- 0.025 -0.110 +/- 0.270 0.018 +/- 0.036 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 04/27/06 0.027 +/- 0.019 0.000 +/- 0.057 0.034 +/- 0.043 15.400 +/- 1.100 -0.002 +/- 0.021 0.011 +/- 0.025 11/07/06 0.030 +/- 0.031 0.033 +/- 0.076 0.014 +/- 0.079 13.200 +/- 1.300 0.013 +/- 0.028 -0.018 +/- 0.032 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 04/27/06 0.012 +/- 0.021 0.060 +/- 0.150 0.019 +/- 0.045 0.348 +/- 0.084 -0.078 +/- 0.060 -0.035 +/- 0.034 11/07/06 0.000 +/- 0.032 0.070 +/- 0.230 -0.012 +/- 0.061 0.440 +/- 0.120 -0.036 +/- 0.073 -0.047 +/- 0.045 39-X

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 15, Bottom Sediment (pCi/g Dry) Page 3 of 3 Location Collection Isotope Date 39-X Ag-ll0m Be-7 Co-58 Co-60 Cr-51 Cs-134 04/26/06 -0.003 +/- 0.038 0.010 +/- 0.270 -0.024 +/- 0.029 0.014 +/- 0.042 0.230 +/- 0.290 -0.002 +/- 0.029 10/17/06 -0.031 +/- 0.062 -0.260 +/- 0.530 0.003 +/- 0.055 0.097 +/- 0.047 0.990 +/- 0.700 0.034 +/- 0.049 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 04/26/06 0.174 +/- 0.057 0.043 +/- 0.079 0.062 +/- 0.078 15.100 +/- 1.400 0.006 +/- 0.032 -0.030 +/- 0.037 10/17/06 0.109 +/- 0.062 -0.050 +/- 0.120 0.380 +/- 0.460 19.500 +/- 1.700 0.000 +/- 0.046 -0.058 +/- 0.074 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 04/26/06 0.004 +/- 0.035 -0.180 +/- 0.270 0.040 +/- 0.070 0.570 +/- 0.140 -0.040 +/- 0.150 -0.018 +/- 0.045 10/17/06 0.000+ 0.064 0.060 +/- 0.430 0.160 +/- 0.120 0.960 +/- 0.200 0.070 +/- 0.220 -0.010 +/- 0.098 67-X Ag-lr0m Be-7 Co-58 Co-60 Cr-51 Cs-134 04/26/06 0.014 +/- 0.052 -0.050 +/- 0.340 -0.035 +/- 0.048 0.047 +/- 0.049 -0.060 +/- 0.360 -0.026 +/- 0.040 11/03/06 0.006 +/- 0.031 0.280 +/- 0.250 -0.017 +/- 0.029 0.0 16 +/- 0.022 -0.130 +/- 0.330 0.005 +/- 0.024 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 04/26/06 0.183 +/- 0.089 -0.100 +/- 0.110 -0.036 +/- 0.080 14.100 +/- 1.800 0.040 +/- 0.045 -0.033 +/- 0.067 11/03/06 0.096 +/- 0.038 0.011 +/- 0.065 -0.070 +/- 0.130 16.830 +/- 0.970 0.009 +/- 0.027 -0.035 +/- 0.041 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 04/26/06 -0.026 +/- 0.044 -0.030 +/- 0.370 0.030 +/- 0.110 1.600 +/- 0.200 0.020 +/- 0.240 -0.029 +/- 0.087 11/03/06 0.009 +/- 0.034 0.130 +/- 0.220 0.034 +/- 0.069 1.820 +/- 0.120 -0.040 +/- 0.120 0.032 +/- 0.054 69-X Ag-ll0m Be-7 Co-58 Co-60 Cr-51 Cs-134 04/26/06 -0.008 +/- 0.037 0.090 +/- 0.180 -0.005 +/- 0.022 -0.001 +/- 0.029 0.180 +/- 0.220 -0.004 +/- 0.021 11/03/06 0.024 +/- 0.022 0.030 +/- 0.180 -0.007 +/- 0.020 0.005 +/- 0.018 0.110 +/- 0.220 0.034 +/- 0.056 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 04/26/06 0.008 +/- 0.027 -0.026 +/- 0.069 -0.010 +/- 0.045 15.400 +/- 1.300 -0.007 +/- 0.025 0.003 +/- 0.025 11/03/06 0.009 +/- 0.018 0.009 +/- 0.050 -0.008 +/- 0.085 15.450 +/- 0.860 0.002 +/- 0.017 -0.033 +/- 0.025 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 04/26/06 -0.017 + 0.022 0.000 +/- 0.200 -0.025 + 0.059 0.140 +/- 0.130 0.000 +/- 0.071 -0.015 +/- 0.032 11/03/06 -0.006 - 0.019 -0.010 +/- 0.160 0.050 +/- 0.048 0.191 +/- 0.071 0.080 +/- 0.085 -0.022 +/- 0.029

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 16, Aquatic Flora - Fucus (pCi/g Dry) Page lof3 Location Collection Isotope Date 29 Ag-110m Be-7 Co-58 Co-60 Cr-51 Cs-134 02/07/06 -0.006 +/- 0.008 0.117 +/- 0.060 0.000 +/- 0.005 0.004 +/- 0.009 0.012 +/- 0.040 0.002 +/- 0.006 05/17/06 -0.020 +/- 0.016 0.080 +/- 0.110 -0.003 +/- 0.012 0.007 +/- 0.020 0.006 +/- 0.094 -0.004 +/- 0.015 08/08/06 -0.002 +/- 0.018 0.060 +/- 0.110 -0.005 +/- 0.014 -0.008 +/- 0.022 -0.060 +/- 0.110 0.001 +/- 0.017 11/20/06 0.004 +/- 0.017 0.140+/-0.110 -0.004 +/- 0.012 -0.004 +/- 0.014 0.010 +/- 0.110 -0.002 +/- 0.014 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 02/07/06 0.001 +/- 0.005 -0.005 +/- 0.014 0.019 +/- 0.012 4.860 +/- 0.300 0.003 +/- 0.005 -0.004 +/- 0.005 05/17/06 -0.001 +/- 0.012 0.000 +/- 0.031 0.002 +/- 0.017 4.360 +/- 0.600 -0.009 +/- 0.014 0.007 +/- 0.013 08/08/06 0.001 +/- 0.014 -0.013 +/- 0.030 -0.005 +/- 0.023 6.690 +/- 0.670 -0.002 +/- 0.013 -0.006 +/- 0.015 11/20/06 -0.001 +/- 0.013 -0.026 +/- 0.032 0.028 +/- 0.022 6.810 +/- 0.540 0.006 +/- 0.012 -0.001 +/- 0.012 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 02/07/06 0.002 +/- 0.005 -0.005 +/- 0.047 -0.007 +/- 0.011 0.023 +/- 0.022 0.002 +/- 0.015 -0.008 +/- 0.009 05/17/06 0.006 +/- 0.010 0.010 +/- 0.120 -0.005 +/- 0.032 -0.035 +/- 0.064 -0.009 +/- 0.026 -0.005 +/- 0.020 08/08/06 -0.011 +/- 0.016 -0.040 +/- 0.130 -0.017 +/- 0.029 0.005 +/- 0.059 -0.006 +/- 0.034 0.004 +/- 0.028 11/20/06 -0.004 +/- 0.011 -0.040 +/- 0.110 -0.001 +/- 0.033 0.042 +/- 0.050 0.012 +/- 0.030 0.001 +/- 0.022 32-X Ag-il0m Be-7 Co-58 Co-60 Cr-51 Cs-134 02/07/06 0.001 +/- 0.002 0.084 +/- 0.020 -0.001 +/- 0.002 -0.001 + 0.002 -0.007 +/- 0.018 0.001 +/- 0.002 05/17/06 -0.001 +/- 0.013 0.072 +/- 0.085 0.009 +/- 0.011 0.003 +/- 0.016 0.044 +/- 0.059 -0.007 +/- 0.012 08/08/06 -0.004 +/- 0.017 0.078 +/- 0.088 -0.003 +/- 0.011 0.001 + 0.016 0.019 +/- 0.086 0.008 +/- 0.013 11/20/06 -0.002 +/- 0.025 0.120 +/- 0.130 0.014 +/- 0.017 0.007 +/- 0.025 -0.010 +/- 0.120 -0.001 +/- 0.020 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 02/07/06 -0.001 +/- 0.002 0.000 +/- 0.005 0.029 +/- 0.011 5.793 +/- 0.085 -0.002 +/- 0.002 0.001 +/- 0.003 05/17/06 0.007 +/- 0.009 -0.003 +/- 0.027 0.006 +/- 0.011 4.220 +/- 0.560 0.005 +/- 0.008 -0.002 +/- 0.012 08/08/06 0.012 +/- 0.013 0.009 +/- 0.027 0.013 +/- 0.018 5.820 +/- 0.530 -0.010 +/- 0.012 -0.003 +/- 0.012 11/20/06 0.011 +/-0.018 0.004 +/- 0.046 0.050 +/- 0.031 6.920 +/- 0.820 0.013 +/- 0.018 0.006 +/- 0.020 Ru- 103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 02/07/06 0.000 + 0.002 0.000 +/- 0.014 -0.001 +/- 0.004 0.040 +/- 0.005 0.003 +/- 0.008 0.002 +/- 0.003 05/17/06 -0.003 +/- 0.009 0.025 +/- 0.087 0.002 +/- 0.025 0.036 +/- 0.043 -0.003 +/- 0.033 0.004 +/- 0.021 08/08/06 -0.002 +/- 0.010 0.060 +/- 0.100 -0.003 +/- 0.025 0.059 +/- 0.053 -0.031 +/- 0.030 0.013 +/- 0.020 11/20/06 0.013 +/- 0.018 -0.060 +/- 0.130 -0.018 +/- 0.046 0.053 +/- 0.077 0.007 +/- 0.041 0.008 +/- 0.033 33-X Ag-110m Be-7 Co-58 Co-60 Cr-51 Cs-134 02/08/06 -0.001 +/- 0.012 0.092 +/- 0.090 -0.001 +/- 0.007 -0.002 +/- 0.013 -0.010 +/- 0.058 0.007 +/- 0.008 05/17/06 -0.004 +/- 0.007 0.060 +/- 0.042 -0.002 +/- 0.005 -0.003 +/- 0.007 0.012 +/- 0.039 0.003 +/- 0.006 08/09/06 0.009 +/- 0.019 0.067 +/- 0.098 -0.001 +/- 0.013 0.002 +/- 0.016 -0.050 +/- 0.100 0.006 +/- 0.016 11/21/06 0.005 +/- 0.028 0.170 +/- 0.170 0.005 +/- 0.022 0.002 +/- 0.023 0.030 +/- 0.170 -0.010 +/- 0.021 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 02/08/06 0.009 +/- 0.008 -0.001 +/- 0.022 0.009 +/- 0.011 6.7 10 +/- 0.470 -0.001 +/- 0.008 0.006 +/- 0.009 05/17/06 0.003 +/- 0.005 0.006 +/- 0.013 0.009 +/- 0.009 4.040 +/- 0.240 0.001 +/- 0.006 -0.004 +/- 0.005 08/09/06 -0.017 +/- 0.013 0.017 +/- 0.027 0.011 +/- 0.019 6.000 +/- 0.550 0.002 +/- 0.014 0.001 +/- 0.015 11/21/06 0.017+/-0.021 -0.012 +/- 0.044 0.030 +/- 0.029 7.220 +/- 0.880 0.000 +/- 0.019 -0.012 +/- 0.020

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 16, Aquatic Flora - Fucus (pCi/g Dry) Page 2 of 3 Location Collection Isotope Date 33-X Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 02/08/06 0.004 +/- 0.007 -0.039 +/- 0.070 0.000 +/- 0.016 0.040 +/- 0.033 0.004 +/- 0.023 0.005 +/- 0.012 05/17/06 -0.003 +/- 0.005 -0.011 +/- 0.047 0.003 +/- 0.011 0.021 +/- 0.020 -0.004 +/- 0.013 0.010 +/- 0.009 08/09/06 0.007 +/- 0.013 0.010 +/- 0.110 0.002 +/- 0.028 0.017 +/- 0.059 0.036 +/- 0.045 0.015 +/- 0.024 11/21/06 -0.012 +/- 0.016 0.040 +/- 0.180 0.015 +/- 0.041 0.036 +/- 0.089 -0.016 +/- 0.050 -0.014 +/- 0.032 35-X Ag-ll0m Be-7 Co-58 Co-60 Cr-51 Cs-134 02/08/06 -0.002 +/- 0.009 0.246 +/- 0.072 -0.002 +/- 0.005 -0.002 +/- 0.008 -0.036 +/- 0.043 0.000 +/- 0.006 05/17/06 -0.001 +/- 0.014 0.082 +/- 0.085 -0.005 +/- 0.012 0.000 +/- 0.013 0.017 +/- 0.078 -0.001 +/- 0.012 08/08/06 -0.005 +/- 0.026 0.150 +/- 0.160 0.002 +/- 0.019 -0.001 +/- 0.028 0.020 +/- 0.150 0.009 +/- 0.016 11/21/06 -0.009 +/- 0.023 0.140 +/- 0.140 -0.002 +/- 0.015 0.003 +/- 0.020 0.200 +/- 0.140 -0.010 +/- 0.016 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 02/08/06 0.004 +/- 0.006 -0.004 +/- 0.014 0.013 +/- 0.012 5.810 +/- 0.320 0.007 +/- 0.006 -0.003 +/- 0.006 05/17/06 0.008 +/- 0.009 -0.024 +/- 0.017 0.016 +/- 0.015 3.950 +/- 0.450 -0.002 +/- 0.011 0.000 +/- 0.011 08/08/06 0.013 +/- 0.021 0.055 +/- 0.046 0.024 +/- 0.033 10.340 +/- 0.990 -0.008 +/- 0.019 -0.008 +/- 0.017 11/21/06 0.006+/- 0.018 -0.015 +/- 0.036 0.025 +/- 0.025 6.080 +/-0.640 -0.005 +/- 0.016 -0.002 +/- 0.016 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 02/08/06 -0.003 +/- 0.005 -0.025 +/- 0.049 -0.002 +/- 0.013 0.060 +/- 0.021 -0.008 +/- 0.016 0.003 +/- 0.011 05/17/06 0.004 +/- 0.009 0.053 +/- 0.088 -0.003 +/- 0.023 0.018 +/- 0.039 0.012 +/- 0.026 -0.004 +/- 0.020 08/08/06 -0.024 +/- 0.019 0.110 +/- 0.170 -0.016 +/- 0.039 0.070 +/- 0.100 -0.028 +/- 0.051 0.031 +/- 0.028 11/21/06 0.005 +/- 0.015 0.110 +/- 0.160 -0.002 +/- 0.041 0.023 +/- 0.074 -0.018 +/- 0.036 0.017 +/- 0.029 36-X Ag-110mi Be-7 Co-58 Co-60 Cr-51 Cs-134 02/08/06 0.001 +/- 0.007 0.118 +/- 0.061 -0.002 +/- 0.005 -0.003 +/- 0.007 -0.004+/- 0.043 -0.003 +/- 0.006 05/17/06 0.003 +/- 0.013 0.080 +/- 0.080 0.001 +/- 0.009 0.008 +/- 0.014 0.031 +/- 0.067 0.007 +/- 0.011 08/09/06 -0.002 +/- 0.014 -0.057 +/- 0.093 0.001 +/- 0.010 -0.003 +/- 0.013 0.034 +/- 0.087 0.009 +/- 0.011 11/20/06 -0.014 +/- 0.018 0.100 +/- 0.120 0.005 +/- 0.014 -0.006 +/- 0.016 -0.090 +/- 0.130 -0.006 +/- 0.017 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 02/08/06 0.002 +/- 0,006 -0.004 +/- 0.013 0.018 +/- 0.010 5.690 +/- 0.290 -0.004 +/- 0.005 -0.006 +/- 0.006 05/17/06 0.001 +/- 0.009 0.009 +/- 0.024 0.011 +/- 0.015 4.110 +/- 0.430 0.004 +/- 0.009 0.007 +/- 0.011 08/09/06 0.004 +/- 0.011 -0.005 +/- 0.026 0.010 +/- 0.017 3.710 +/- 0.450 -0.001 +/- 0.010 0.002 +/- 0.012 11/20/06 0.013 +/- 0.015 -0.022 +/- 0.031 0.015 +/- 0.029 6.550 +/- 0.600 0.001 +/- 0.013 -0.007 +/- 0.014 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 02/08/06 -0.002 +/- 0.004 0.038 +/- 0.043 0.005 +/- 0.012 0.053 +/- 0.024 -0.014 +/- 0.016 0.001 +/- 0.009 05/17/06 -0.004 +/- 0.009 0.000 +/- 0.081 0.000 +/- 0.023 0.027 +/- 0.038 0.012 +/- 0.023 0.014 +/- 0.016 08/09/06 0.010 +/- 0.010 0.007 +/- 0.089 -0.020 +/- 0.027 -0.003 +/- 0.041 -0.028 +/- 0.030 0.004 +/- 0.018 11/20/06 -0.008 +/- 0.014 0.060 +/- 0.130 0.002 +/- 0.035 0.073 +/- 0.058 -0.001 +/- 0.039 -0.003 +/- 0.024 90-C Ag-I lOm Be-7 Co-58 Co-60 Cr-51 Cs-134 08/09/06 -0.007 +/- 0.013 0.186 +/- 0.095 -0.002 +/- 0.009 0.000 +/- 0.016 -0.029 +/- 0.075 0.009 +/- 0.011 11/21/06 -0.004 +/- 0.021 0.080 +/- 0.130 0.015 +/- 0.017 0.006 +/- 0.019 -0.100 +/- 0.110 0.004 +/- 0.021

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 16, Aquatic Flora - Fucus (pCi/g Dry) Page 3 of 3 Location Collection Isotope Date 90-C Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 08/09/06 0.012 +/- 0.009 0.009 +/- 0.024 0.072 +/- 0.022 10.140 + 0.550 -0.003 +/- 0.010 -0.007 +/- 0.010 11/21/06 -0.001 +/- 0.016 -0.011 +/- 0.036 0.142 +/- 0.038 6.430 0.690 -0.011 +/- 0.018 -0.009 +/- 0.018 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 08/09/06 -0.003 +/- 0.010 -0.006 +/- 0.079 0.007 +/- 0.019 0.060 +/- 0.038 -0.021 +/- 0.029 0.012 +/- 0.017 11/21/06 -0.012 +/- 0.013 -0.110+/- 0.140 0.000 +/- 0.034 0.098 +/- 0.061 -0.040 +/- 0.039 -0.004 +/- 0.027

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 17-A, Fish - Flounder (pCi/g Dry) Page I of I Location Collection Isotope Date 32 Ag-110m Be-7 Co-58 Co-60 Cr-51 Cs-134 03/30/06 1 05/31/06 -0.023 +/- 0.039 0.020 +/- 0.260 0.024 +/- 0.025 -0.005 +/- 0.030 -0.100 +/- 0.270 -0.013 +/- 0.030 07/12/06 -0.014 +/- 0.034 0.190 +/- 0.280 -0.020 +/- 0.027 -0.010 +/- 0.040 -0.080 +/- 0.250 -0.003 +/- 0.026 10/03/06 -0.027 +/- 0.033 0.010 +/- 0.200 -0.002 +/- 0.024 0.009 +/- 0.028 0.190 +/- 0.250 0.012 +/- 0.026 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 05/31/06 0.011 +/- 0.033 -0.017 +/- 0.061 -0.020 + 0.052 4.690 +/- 0.790 0.035 +/- 0.028 -0.021 +/- 0.030 07/12/06 0.003 +/- 0.042 0.023 +/- 0.099 0.029 +/- 0.053 3.700 +/- 1.100 0.009 +/- 0.038 0.018 +/- 0.038 10/03/06 -0.001 +/- 0.026 -0.025 + 0.058 0.004 +/- 0.082 3.960 +/- 0.610 0.006 +/- 0.023 -0.011 +/- 0.029 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 05/31/06 0.004 +/- 0.028 -0.090 +/- 0.270 -0.044 +/- 0.081 0.000 + 0.120 -0.014 +/- 0.066 0.003 + 0.046 07/12/06 -0.004 +/- 0.024 -0.040 +/- 0.290 -0.028 +/- 0.082 0.020 +/- 0.140 0.047 +/- 0.089 -0.003 +/- 0.047 10/03/06 -0.002 +/- 0.025 -0.210 +/- 0.250 -0.033 +/- 0.061 -0.007 + 0.094 0.024 +/- 0.062 -0.006 +/- 0.045 35 Ag-ll0m Be-7 Co-58 Co-60 Cr-51 Cs-134 03/30/06 1 04/17/06 0.007 +/- 0.031 0.000 +/- 0.170 -0.006 +/- 0.025 0.006 +/- 0.030 0.000 +/- 0.190 0.001 +/- 0.027 07/12/06 0.011 +/- 0.032 -0.160 +/- 0.220 -0.008 +/- 0.027 -0.003 +/- 0.030 -0.020 +/- 0.260 0.008 +/- 0.030 11/15/06 -0.007 +/- 0.015 0.004 +/- 0.085 -0.008 +/- 0.011 0.002 +/- 0.012 -0.011 +/- 0.097 0.008 +/- 0.013 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 04/17/06 0.020 +/- 0.019 0.044 +/- 0.055 -0.029 +/- 0.057 2.910 +/- 0.850 -0.016 +/- 0.019 -0.016 +/- 0.026 07/12/06 -0.002 +/- 0.035 0.038 +/- 0.054 0.000 +/- 0.047 3.700 +/- 1.000 0.004 +/- 0.026 0.010 +/- 0.025 11/15/06 -0.003 +/- 0.011 -0.021 +/- 0.025 0.005 +/- 0.019 3.840 +/- 0.400 0.012 +/- 0.011 0.016 +/- 0.013 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 04/17/06 -0.006 +/- 0.021 0.030 +/- 0.190 0.000 +/- 0.061 -0.040 +/- 0.096 -0.013 +/- 0.053 0.001 +/- 0.035 07/12/06 -0.007 +/- 0.021 -0.160 +/- 0.330 -0.031 +/- 0.075 -0.010 +/- 0.110 -0.029 +/- 0.052 -0.007 +/- 0.049 11/15/06 -0.004 +/- 0.012 -0.050 +/- 0.110 0.008 +/- 0.028 0.008 +/- 0.044 -0.024 +/- 0.030 -0.003 +/- 0.020

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 17-B, Fish - Other (pCi/g Dry) Page 1of 2 Location Collection Sample Type Isotope Date 32 Ag-110m Be-7 Co-58 Co-60 Cr-51 03/30/06 FISH-OTHER K 06/06/06 TAUTOG 0.036 +/- 0.036 0.030 +/- 0.230 0.015 +/- 0.025 -0.011 +/- 0.030 -0.010 +/- 0.200 08/28/06 TAUTOG 0.034 +/- 0.033 -0.050 +/- 0.200 0.019 +/- 0.019 -0.006 +/- 0.023 0.060 +/- 0.220 10/31/06 TAUTOG 0.000 +/- 0.010 0.038 +/- 0.054 -0.012 +/- 0.007 0.005 +/- 0.007 -0.041 +/- 0.063 12/18/06 STRIPED BASS 0.001 +/- 0.008 -0.030 +/- 0.046 0.001 +/- 0.006 0.004 +/- 0.007 0.028 +/- 0.048 Cs-134 Cs-137 Fe-59 1-131 K-40 06/06/06 TAUTOG -0.018 +/- 0.032 0.019 +/- 0.031 0.051 +/- 0.068 0.008 +/- 0.039 2.960 +/- 0.940 08/28/06 TAUTOG 0.002 +/- 0.018 0.004 +/- 0.026 -0.006 +/- 0.052 0.010 +/- 0.055 3.680 +/- 0.770 10/31/06 TAUTOG -0.002 +/- 0.007 0.000 +/- 0.007 -0.004 +/- 0.017 -0.004 +/- 0.019 3.770 +/- 0.240 12/18/06 STRIPED BASS -0.003 +/- 0.006 0.006 +/- 0.006 0.006 +/- 0.015 0.002 +/- 0.016 3.620 +/- 0.220 Mn-54 Nb-95 Ru-103 Ru-106 Sb-125 06/06/06 TAUTOG -0.004 +/- 0.030 0.006 +/- 0.029 -0.006 +/- 0.026 0.160 +/- 0.190 -0.007 +/- 0.077 08/28/06 TAUTOG -0.014 +/- 0.025 0.018 +/- 0.027 -0.024 +/- 0.025 0.130 +/- 0.220 0.005 +/- 0.060 10/31/06 TAUTOG -0.003 +/- 0.007 0.008 +/- 0.008 0.004 +/- 0.007 0.042 +/- 0.062 -0.005 +/- 0.015 12/18/06 STRIPED BASS -0.001 +/- 0.005 0.004 +/- 0.008 -0.001 +/- 0.006 0.026 +/- 0.046 -0.005 +/- 0.013 Th-228 Zn-65 Zr-95 06/06/06 TAUTOG -0.040 +/- 0.100 -0.010 +/- 0.061 0.012 +/- 0.037 08/28/06 TAUTOG -0.072 +/- 0.092 0.006 +/- 0.071 0.035 +/- 0.041 10/31/06 TAUTOG -0.009 +/- 0.034 -0.003 +/- 0.016 -0.010 +/- 0.012 12/18/06 STRIPED BASS 0.014 +/- 0.035 -0.006 +/- 0.014 0.003 +/- 0.013 35 Ag-110m Be-7 Co-58 Co-60 Cr-51 03/30/06 FISH-OTHER K 06/06/06 TAUTOG -0.003 +/- 0.043 -0.030 +/- 0.310 0.011 +/- 0.035 0.048 +/- 0.042 0.190 +/- 0.360 08/24/06 STRIPED BASS -0.020 +/- 0.032 0.190 +/- 0.190 0.006 +/- 0.025 0.021 +/- 0.027 -0.070 +/- 0.200 10/04/06 TAUTOG 0.007 +/- 0.019 0.000 +/- 0.120 -0.005 +/- 0.015 -0.011 +/- 0.016 -0.030 +/- 0.150 Cs-134 Cs-137 Fe-59 1-131 K-40 06/06/06 TAUTOG -0.001 +/- 0.034 0.061 +/- 0.041 0.054 +/- 0.071 0.010 +/- 0.110 4.340 +/- 0.930 08/24/06 STRIPED BASS -0.003 +/- 0.022 0.010 +/- 0.021 0.023 +/- 0.055 -0.067 +/- 0.082 4.100 +/- 0.830 10/04/06 TAUTOG -0.002 +/- 0.016 -0.006 +/- 0.013 0.007 +/- 0.036 0.009 +/- 0.044 4.100 +/- 0.510 Mn-54 Nb Ru-103 Ru-106 Sb-125 06/06/06 TAUTOG 0.011 +/- 0.037 -0.016 +/- 0.039 -0.006 +/- 0.038 -0.150 +/- 0.310 0.004 +/- 0.082 08/24/06 STRIPED BASS 0.008 +/- 0.022 -0.015 +/- 0.032 0.012 +/- 0.027 0.040 +/- 0.180 -0.029 +/- 0.057 10/04/06 TAUTOG 0.002 +/- 0.016 -0.001 +/- 0.021 0.001 +/- 0.017 0.030 +/- 0.140 -0.020 +/- 0.036 Th-228 Zn-65 Zr-95 06/06/06 TAUTOG 0.010 +/- 0.150 -0.033 +/- 0.073 0.035 +/- 0.060 08/24/06 STRIPED BASS 0.008 +/- 0.086 0.027 +/- 0.061 0.037 +/- 0.043 10/04/06 TAUTOG -0.038 +/- 0.057 0.009 +/- 0.033 0.013 +/- 0.027 40-X Ag-110m Be-7 Co-58 Co-60 Cr-51 03/08/06 STRIPED BASS 0.007 +/- 0.020 0.020 +/- 0.150 0.009 +/- 0.019 0.010 +/- 0.022 -0.090 +/- 0.130 06/19/06 STRIPED BASS -0.013 +/- 0.023 0.000 +/- 0.130 0.000 +/- 0.017 -0.014 +/- 0.019 -0.010 +/- 0.160 Cs-134 Cs-137 Fe-59 1-131 K-40 03/08/06 STRIPED BASS -0.011 +/- 0.019 0.007 +/- 0.017 -0.008 +/- 0.037 0.021 +/- 0.039 3.610 +/- 0.600 06/19/06 STRIPED BASS 0.008 +/- 0.017 0.003 +/- 0.015 -0.006 +/- 0.042 -0.016 +/- 0.030 3.730 +/- 0.540

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 17-B, Fish - Other (pCi/g Dry) Page 2 of 2 Location Collection Sample Type Isotope Date 40-X Mn-54 Nb-95 Ru-103 Ru-106 Sb-125 03/08/06 STRIPED BASS 0.002 +/- 0.015 -0.015 +/- 0.019 0.001 +/- 0.017 -0.020 +/- 0.120 0.003 +/- 0.039 06/19/06 STRIPED BASS -0.007 +/- 0.017 0.005 +/- 0.018 0.001 +/- 0.016 0.000 +/- 0.140 -0.016 +/- 0.039 Th-228 Zn-65 Zr-95 03/08/06 STRIPED BASS 0.015 +/- 0.060 -0.012 +/- 0.041 -0.015 + 0.030 06/19/06 STRIPED BASS -0.016 +/- 0.061 0.001 +/- 0.039 0.010 +/- 0.028

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 18, Mussels (pCi/g Dry) Page I of I Location Collection Isotope Date 28 Ag-110m Be-7 Co-58 Co-60 Cr-51 Cs-134 03/23/06 -0.006 +/- 0.029 0.120 +/- 0.160 -0.002 +/- 0.022 -0.016 +/- 0.021 0.040 +/- 0.200 0.021 +/- 0.023 05/24/06 -0.003 +/- 0.028 0.180 +/- 0.200 0.004 +/- 0.020 0.004 +/- 0.025 0.010 +/- 0.170 0.021 +/- 0.020 07/10/06 -0.006 +/- 0.017 0.080 +/- 0.100 -0.008 +/- 0.012 0.003 +/- 0.016 -0.100 +/- 0.110 0.005 +/- 0.012 12/18/06 -0.012 +/- 0.019 0.090 +/- 0.130 -0.006 +/- 0.013 0.009 +/- 0.013 -0.070 +/- 0.160 -0.009 +/- 0.015 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 03/23/06 0.005 +/- 0.023 0.028 +/- 0.048 0.012 +/- 0.057 1.790 +/- 0.540 -0.021 +/- 0.025 0.016 +/- 0.027 05/24/06 0.006 +/- 0.024 0.009 +/- 0.040 -0.017 +/- 0.038 1.560 +/- 0.500 -0.004 +/- 0.018 0.000 +/- 0.021 07/10/06 -0.009 +/- 0.013 0.000 +/- 0.024 0.005 +/- 0.028 2.120 +/- 0.350 -0.002 +/- 0.011 -0.012 +/- 0.015 12/18/06 0.010+/- 0.014 0.022 +/- 0.029 0.021 +/- 0.050 1.730 +/- 0.360 0.004 +/- 0.014 0.008 +/- 0.016 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 03/23/06 0.000 +/- 0.022 -0.080 +/- 0.190 0.004 +/- 0.057 0.047 +/- 0.092 0.018 +/- 0.041 0.004 +/- 0.040 05/24/06 -0.002 +/- 0.017 0.060 +/- 0.190 0.034 +/- 0.054 0.064 +/- 0.077 -0.034 +/- 0.046 0.007 +/- 0.037 07/10/06 -0.001 +/- 0.013 -0.010 +/- 0.130 -0.003 +/- 0.027 0.007 +/- 0.054 -0.002 +/- 0.030 -0.014 +/- 0.021 12/18/06 -0.004 +/- 0.015 -0.010 +/- 0.120 0.029 +/- 0.035 0.023 +/- 0.057 -0.007 +/- 0.030 -0.004 +/- 0.026 30 Ag-110m Be-7 Co-58 Co-60 Cr-51 Cs-134 03/22/06 0.009 +/- 0.030 0.070 +/- 0.210 -0.017 +/- 0.021 0.004 +/- 0.019 0.020 +/- 0.210 0.004 +/- 0.019 06/19/06 0.026 +/- 0.025 0.110+/--0.180 -0.004 +/- 0.017 -0.007 +/- 0.021 -0.040 +/- 0.160 0.004 +/- 0.022 08/08/06 -0.013 +/- 0.020 0.080 +/- 0.130 0.000 +/- 0.016 -0.006 +/- 0.020 0.050 +/- 0.100 -0.010 +/- 0.020 11/30/06 -0.003 +/- 0.010 0.093 +/- 0.068 -0.001 +/- 0.007 -0.006 +/- 0.009 0.022 +/- 0.074 -0.009 +/- 0.007 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 03/22/06 -0.004 +/- 0.022 -0.023 +/- 0.047 0.036 +/- 0.063 1.750 +/- 0.550 -0.002 +/- 0.025 0.010 +/- 0.021 06/19/06 -0.027 +/- 0.022 0.022 +/- 0.037 -0.001 +/- 0.042 1.840 +/- 0.500 0.008 +/- 0.018 -0.004 +/- 0.019 08/08/06 0.001 +/- 0.016 -0.015 +/- 0.039 0.001 +/- 0.021 1.900 +/- 0.470 -0.005 +/- 0.017 -0.010 +/- 0.020 11/30/06 0.006 +/- 0.008 -0.009 +/- 0.018 0.008 +/- 0.024 1.470 +/- 0.190 -0.005 +/- 0.007 -0.001 +/- 0.008 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 03/22/06 0.005 +/- 0.018 0.140 +/- 0.190 -0.023 +/- 0.058 0.072 +/- 0.079 -0.005 +/- 0.046 0.008 +/- 0.035 06/19/06 -0.011 +/- 0.018 -0.050 +/- 0.170 0.001 +/- 0.053 0.071 +/- 0.072 -0.006 +/- 0.046 0.007 +/- 0.031 08/08/06 0.006 +/- 0.014 0.130 +/- 0.140 -0.011 +/- 0.038 -0.001 +/- 0.073 -0.023 +/- 0.045 -0.012 +/- 0.030 11/30/06 0.001 +/- 0.008 -0.028 +/- 0.065 -0.004 +/- 0.017 -0.003 +/- 0.034 -0.012 +/- 0.017 0.015 +/- 0.014

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 19, Oysters (pCi/g Dry) Page lof 3 Location Collection Isotope Date 31 Ag-ll0m Be-7 Co-58 Co-60 Cr-51 Cs-134 03/09/06 0.000 +/- 0.025 -0.080 +/- 0.130 0.007 +/- 0.017 0.001 +/- 0.019 -0.020 +/- 0.160 0.005 +/- 0.015 06/12/06 0.005 +/- 0.039 0.070 +/- 0.220 -0.016 +/- 0.025 0.011 +/- 0.029 0.100 +/- 0.230 -0.008 +/- 0.022 09/27/06 0.013 +/- 0.027 -0.010 +/- 0.170 -0.005 +/- 0.021 0.017 +/- 0.019 -0.100 +/- 0.170 0.002 +/- 0.019 11/30/06 -0.011 +/- 0.017 -0.040 +/- 0.130 -0.007 +/- 0.015 0.014 +/- 0.017 -0.040 +/- 0.110 -0.003 +/- 0.016 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 03/09/06 -0.007 +/- 0.018 -0.025 +/- 0.041 0.000 +/- 0.047 1.390 +/- 0.390 -0.008 +/- 0.016 0.011 +/- 0.019 06/12/06 0.017 +/- 0.023 -0.024 +/- 0.049 0.000 +/- 0.045 2.340 +/- 0.750 -0.010 +/- 0.022 0.037 +/- 0.030 09/27/06 -0.020 +/- 0.021 0.002 +/- 0.029 0.000 +/- 0.031 1.700 +/- 0.460 -0.005 +/- 0.019 -0.009 +/- 0.022 11/30/06 -0.001 +/- 0.013 0.007 +/- 0.037 -0.010 +/- 0.035 1.580 +/- 0.390 0.008 +/- 0.014 -0.003 +/- 0.020 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 03/09/06 0.000 +/- 0.018 -0.030 +/- 0.170 -0.026 +/- 0.038 -0.016 +/- 0.068 -0.017 +/- 0.032 0.004 +/- 0.030 06/12/06 -0.011 +/- 0.024 -0.080 +/- 0.270 -0.019 +/- 0.062 0.036 +/- 0.097 0.000 +/- 0.046 0.011 +/- 0.043 09/27/06 0.005 +/- 0.017 -0.040 +/- 0.180 0.004 +/- 0.049 -0.043 +/- 0.074 -0.063 +/- 0.054 0.009 +/- 0.033 11/30/06 -0.012 +/- 0.014 -0.060 +/- 0.120 0.007 +/- 0.033 0.010 +/- 0.053 -0.013 +/- 0.032 -0.004 +/- 0.030 32 Ag-ll0m Be-7 Co-58 Co-60 Cr-51 Cs-134 03/07/06 0.019 +/- 0.022 0.050 +/- 0.140 -0.001 +/- 0.021 0.004 +/- 0.018 0.030 +/- 0.160 -0.006 +/- 0.020 06/13/06 0.077 +/- 0.034 0.020 +/- 0.180 0.003 +/- 0.026 -0.004 +/- 0.030 0.000 +/- 0.190 0.000 +/- 0.027 09/27/06 0.046 +/- 0.018 -0.130 +/- 0.130 -0.002 +/- 0.015 -0.009 +/- 0.018 0.080 +/- 0.110 0.005 +/- 0.017 12/13/06 0.061 +/- 0.044 0.110 +/- 0.200 -0.013 +/- 0.031 0.004 +/- 0.034 -0.080 +/- 0.220 0.014 +/- 0.038 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 03/07/06 -0.010 +/- 0.017 -0.026 +/- 0.045 0.020 +/- 0.047 2.050 +/- 0.480 -0.006 +/- 0.019 -0.009 +/- 0.023 06/13/06 -0.046 +/- 0.080 -0.039 +/- 0.041 0.028 +/- 0.047 1.750 +/- 0.750 0.000 +/- 0.024 0.053 +/- 0.037 09/27/06 -0.013 +/- 0.044 0.003 +/- 0.027 -0.005 +/- 0.023 2.250 +/- 0.470 0.003 +/- 0.013 -0.015 +/- 0.019 12/13/06 -0.023 +/- 0.032 0.011 +/- 0.066 -0.036 +/- 0.052 0.910 +/- 0.620 0.006 +/- 0.025 -0.006 +/- 0.039 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 03/07/06 -0.011 +/- 0.020 -0.050 +/- 0.140 0.025 +/- 0.043 0.040 +/- 0.068 0.086 +/- 0.074 -0.022 +/- 0.032 06/13/06 -0.027 +/- 0.024 0.050 +/- 0.210 0.017 +/- 0.053 0.059 +/- 0.088 0.024 +/- 0.053 0.015 +/- 0.053 09/27/06 -0.007 +/- 0.015 -0.010 +/- 0.150 -0.025 +/- 0.040 -0.021 +/- 0.053 0.009 +/- 0.039 0.000 +/- 0.025 12/13/06 0.000 +/- 0.030 -0.190 +/- 0.270 -0.015 +/- 0.067 -0.012 +/- 0.068 -0.063 +/- 0.052 0.034 +/- 0.048 34-X Ag-ll0m Be-7 Co-58 Co-60 Cr-51 Cs-134 03/09/06 -0.021 +/- 0.024 0.050 +/- 0.140 -0.008 +/- 0.019 0.008 +/- 0.021 -0.030 +/- 0.160 -0.002 +/- 0.015 06/12/06 -0.017 +/- 0.043 0.120 +/- 0.220 0.014 +/- 0.023 0.002 +/- 0.036 0.060 +/- 0.220 0.003 +/- 0.025 09/27/06 0.003 +/- 0.029 0.060 +/- 0.160 -0.006 +/- 0.018 0.004 +/- 0.024 -0.070 +/- 0.180 -0.005 +/- 0.016 12/04/06 0.008 +/- 0.023 0.020 +/- 0.110 -0.007 +/- 0.016 0.002 +/- 0.018 -0.010 +/- 0.140 -0.009 +/- 0.017 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 03/09/06 -0.006 +/- 0.019 0.013 +/- 0.041 0.006 +/- 0.044 1.860 +/- 0.520 -0.010 +/- 0.017 0.001 +/- 0.021 06/12/06 -0.002 +/- 0.019 0.010 +/- 0.051 0.000 +/- 0.048 2.090 +/- 0.750 0.007 +/- 0.028 -0.012 +/- 0.029 09/27/06 0.022 +/- 0.019 0.035 +/- 0.042 0.004 +/- 0.029 2.110 +/- 0.530 0.010 +/- 0.019 0.009 +/- 0.021 12/04/06 0.002 +/- 0.015 0.007 +/- 0.042 -0.030 +/- 0.035 2.400 +/- 0.490 0.014 +/- 0.014 0.006 +/- 0.019

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 19, Oysters (pCi/g Dry) Page 2 of 3 Location Collection Isotope Date 34-X Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 03/09/06 0.000 +/- 0.018 -0.090 +/- 0.140 0.006 +/- 0.042 0.005 -0.073 -0.012 +/- 0.049 -0.022 +/- 0.031 06/12/06 -0.009 +/- 0.029 -0.120 +/- 0.220 -0.057 +/- 0.053 0.020 + 0.100 0.000 +/- 0.078 -0.040 +/- 0.041 09/27/06 -0.004 +/- 0.017 0.030 +/- 0.150 -0.017 +/- 0.047 -0.037 + 0.076 0.036 +/- 0.040 0.011 +/- 0.031 12/04/06 -0.010 +/- 0.014 -0.020 +/- 0.140 0.000 +/- 0.039 0.062 + 0.074 -0.017 +/- 0.036 -0.005 +/- 0.029 36 Ag-110m Be-7 Co-58 Co-60 Cr-51 Cs-134 03/30/06 L 06/15/06 -0.006+/- 0.028 -0.040 +/- 0.140 -0.002 +/- 0.018 0.011 +/- 0.023 -0.030 +/- 0.190 0.005 +/- 0.019 09/26/06 0.036 +/- 0.025 -0.080 +/- 0.130 0.010 +/- 0.018 0.016 +/- 0.022 -0.030 +/- 0.160 -0.005 +/- 0.017 12/11/06 0.038 +/- 0.035 -0.200 +/- 0.220 0.000 +/- 0.022 0.008 +/- 0.032 0.000 +/- 0.270 -0.002 +/- 0.026 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 06/15/06 -0.012 +/- 0.021 -0.021 +/- 0.043 0.007 +/- 0.030 1.360 +/- 0.570 0.009 +/- 0.021 -0.001 1 0.023 09/26/06 0.011 +/- 0.022 0.013 +/- 0.038 0.000 +/- 0.038 2.090 +/- 0.540 0.001 +/- 0.016 -0.003 +/- 0.017 12/11/06 -0.001 +/- 0.024 -0.015 +/- 0.063 0.042 +/- 0.092 1.750 +/- 0.610 -0.009 +/- 0.022 0.014 +/- 0.029 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 06/15/06 -0.013 +/- 0.017 -0.090 +/- 0.210 0.001 +/- 0.059 0.008 +/- 0.072 -0.058 +/- 0.051 0.008 +/- 0.025 09/26/06 0.002 +/- 0.019 -0.070 +/- 0.200 -0.020 +/- 0.047 -0.003 +/- 0.076 0.018 +/- 0.035 0.002 +/- 0.031 12/11/06 0.005 +/- 0.025 -0.200 +/- 0.190 0.012 +/- 0.067 0.027 +/- 0.087 -0.054 +/- 0.069 0.017 +/- 0.040 37-C Ag-il0m Be-7 Co-58 Co-60 Cr-51 Cs-134 03/08/06 0.004+/-0.021 -0.070+/- 0.110 0.014+/- 0.016 -0.005 +/- 0.015 0.050+/-0.140 -0.009 +/- 0.014 06/15/06 0.002 +/- 0.030 -0.200 +/- 0.300 -0.014 +/- 0.025 0.000 +/- 0.035 0.170 +/- 0.220 0.010 +/- 0.031 09/26/06 0.014 +/- 0.021 0.000 +/- 0.120 -0.014 +/- 0.014 0.008 +/- 0.018 0.020 +/- 0.140 -0.004 +/- 0.019 12/11/06 0.000 +/- 0.007 -0.006 +/- 0.047 -0.002 +/- 0.005 0.001 +/- 0.005 0.046 +/- 0.077 0.006 +/- 0.005 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 03/08/06 0.006 +/- 0.015 -0.002 +/- 0.036 0.023 +/- 0.044 1.870 +/- 0.370 0.008 +/- 0.014 0.001 1 0.015 06/15/06 0.015 +/- 0.027 0.013 +/- 0.060 0.007 +/- 0.040 2.340 +/- 0.980 -0.010 +/- 0.035 0.000 +/- 0.044 09/26/06 -0.001 +/- 0.015 -0.011 +/- 0.034 -0.003 +/- 0.034 1.870 +/- 0.390 -0.015 +/- 0.015 -0.006 +/- 0.016 12/11/06 0.002 +/- 0.005 0.010 +/- 0.013 -0.002 +/- 0.030 1.980 +/- 0.140 -0.002 +/- 0.006 0.006 +/- 0.007 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 03/08/06 0.001 +/- 0.015 0.050 +/- 0.130 0.030 +/- 0.035 -0.039 +/- 0.051 -0.014 +/- 0.035 -0.009 +/- 0.027 06/15/06 0.004 +/- 0.028 -0.040 +/- 0.190 0.000 +/- 0.069 -0.056 +/- 0.067 -0.042 +/- 0.073 -0.008 +/- 0.065 09/26/06 -0.001 +/- 0.016 -0.030 +/- 0.140 -0.005 +/- 0.039 -0.005 +/- 0.053 -0.037 +/- 0.035 0.004 +/- 0.030 12/11/06 0.003 +/- 0.006 -0.017 +/- 0.047 0.000 +/- 0.013 0.007 +/- 0.026 -0.001 +/- 0.011 0.003 +/- 0.012 40-X Ag-lOnm Be-7 Co-58 Co-60 Cr-51 Cs-134 03/30/06 0.063 +/- 0.024 -0.090 +/- 0.180 -0.002 +/- 0.022 0.008 +/- 0.023 -0.010 +/- 0.170 -0.019 +/- 0.022 06/20/06 0.024 +/- 0.055 -0.200 +/- 0.330 0.000 +/- 0.041 0.002 +/- 0.036 0.130 +/- 0.330 0.001 +/- 0.035 09/19/06 0.061 +/- 0.020 -0.050 +/- 0.130 -0.007 +/- 0.014 -0.001 +/- 0.016 0.100 +/- 0.110 -0.004 +/- 0.016 11/21/06 0.091 +/- 0.008 0.019 +/- 0.055 0.007 +/- 0.006 -0.004 +/- 0.007 -0.047 +/- 0.061 0.003 +/- 0.006

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 19, Oysters (pCi/g Dry) Page 3 of 3 Location Collection Isotope Date 40-X Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 03/30/06 -0.033 +/- 0.027 -0.017 +/- 0.029 0.008 +/- 0.032 2.420 +/- 0.560 -0.013 +/- 0.017 0.021 +/- 0.024 06/20/06 -0.016 +/- 0.048 0.016 +/- 0.079 -0.004 +/- 0.071 0.990 +/- 0.660 0.014 +/- 0.037 -0.011 +/- 0.045 09/19/06 -0.002 +/- 0.046 0.020 +/- 0.032 0.004 +/- 0.049 1.930 +/- 0.380 -0.004 +/- 0.013 0.006 +/- 0.022 11/21/06 0.002+/- 0.018 0.005 +/- 0.014 -0.009 +/- 0.020 2.060 +/- 0.170 0.003 +/- 0.006 -0.012 +/- 0.012 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 03/30/06 -0.002 +/- 0.018 -0.110+/- 0.200 -0.016+/- 0.052 -0.013 +/- 0.070 -0.004 +/- 0.037 0.013 +/- 0.039 06/20/06 -0.007 +/- 0.036 -0.130 +/- 0.340 0.076 +/- 0.098 0.030 +/- 0.140 -0.065 +/- 0.085 0.000 +/- 0.066 09/19/06 -0.005 +/- 0.017 0.000 +/- 0.110 0.018 +/- 0.033 0.057 +/- 0.069 -0.023 +/- 0.038 0.006 +/- 0.026 11/21/06 -0.001 +/- 0.007 0.002 +/- 0.062 -0.010+/- 0.016 0.017 +/- 0.032 -0.007 +/- 0.014 0.002 +/- 0.011

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 20, Clams (pCi/g Dry) Page lof 2 Location Collection Isotope Date 29 Ag-110m Be-7 Co-58 Co-60 Cr-51 Cs-134 03/23/06 0.004 +/- 0.036 0.000 +/- 0.210 -0.008 +/- 0.024 -0.002 +/- 0.022 -0.140 +/- 0.210 0.006 +/- 0.025 06/20/06 0.000 +/- 0.034 -0.020 +/- 0.170 -0.013 +/- 0.022 0.012 +/- 0.030 0.140 +/- 0.170 0.030 +/- 0.029 08/30/06 -0.016 +/- 0.029 0.110 +/- 0.150 0.005 +/- 0.018 0.013 +/- 0.021 0.190 +/- 0.220 -0.008 +/- 0.020 11/15/06 0.006 +/- 0.014 -0.106 +/- 0.087 -0.004 +/- 0.010 -0.002 +/- 0.011 0.039 +/- 0.095 0.009 +/- 0.011 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 03/23/06 0.014 +/- 0.024 -0.007 +/- 0.049 -0.010 +/- 0.060 1.520 +/- 0.650 0.000 +/- 0.020 -0.024 +/- 0.027 06/20/06 -0.002 +/- 0.018 -0.007 +/- 0.041 -0.004 +/- 0.040 2.030 +/- 0.690 0.008 +/- 0.024 0.010 +/- 0.021 08/30/06 0.001 +/- 0.016 -0.007 +/- 0.059 -0.048 +/- 0.059 1.870 +/- 0.600 -0.005 +/- 0.018 -0.002 +/- 0.026 11/15/06 0.000 +/- 0.012 0.009 +/- 0.022 0.008 +/- 0.017 2.090 +/- 0.290 0.007 +/- 0.011 0.001 +/- 0.010 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 03/23/06 -0.005 +/- 0.023 -0.060 +/- 0.220 -0.067 +/- 0.057 -0.003 +/- 0.090 -0.039 +/- 0.062 0.000 +/- 0.038 06/20/06 0.000 +/- 0.021 -0.030 +/- 0.260 0.043 +/- 0.061 0.002 +/- 0.082 0.007 +/- 0.049 0.010 +/- 0.038 08/30/06 -0.012 +/- 0.022 -0.200 +/- 0.210 0.005 +/- 0.048 -0.039 +/- 0.085 -0.007 +/- 0.050 0.006 +/- 0.037 11/15/06 0.001 +/- 0.010 -0.038 +/- 0.097 0.017 +/- 0.028 0.058 +/- 0.040 -0.008 +/- 0.020 0.003 +/- 0.019 35-X Ag-110m Be-7 Co-58 Co-60 Cr-51 Cs-134 03/23/06 -0.013 +/- 0.035 -0.060 +/- 0.150 0.011 +/- 0.027 0.000 +/- 0.030 -0.060 +/- 0.200 -0.007 +/- 0.038 06/20/06 0.003 +/- 0.026 -0.040 +/- 0.160 -0.007 +/- 0.027 -0.020 +/- 0.022 0.030 +/- 0.170 --0.010 +/- 0.024 09/19/06 0.007 +/- 0.030 -0.100 +/- 0.190 0.004 +/- 0.023 -0.004 +/- 0.017 0.050 +/- 0.210 -0.013 +/- 0.022 11/15/06 0.002 +/- 0.022 0.020 +/- 0.120 -0.007 +/- 0.016 -0.002 +/- 0.017 0.100 +/- 0.140 -0.003 +/- 0.018 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 03/23/06 -0.012 +/- 0.019 -0.009 +/- 0.071 0.042 +/- 0.044 1.570 +/- 0.650 -0.008 +/- 0.029 0.014 +/- 0.022 06/20/06 0.014 +/- 0.025 0.000 +/- 0.049 -0.006 +/- 0.035 2.190 +/- 0.720 -0.008 +/- 0.017 0.010 +/- 0.026 09/19/06 0.022 +/- 0.019 -0.037 +/- 0.056 0.022 +/- 0.076 1.700 +/- 0.630 -0.006 +/- 0.024 0.013 +/- 0.028 11/15/06 -0.009 +/- 0.016 -0.018 +/- 0.035 -0.004 +/- 0.028 1.690 +/- 0.400 0.008 +/- 0.017 0.005 +/- 0.022 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 03/23/06 -0.016 +/- 0.025 0.150 +/- 0.200 0.018 +/- 0.059 -0.006 +/- 0.084 -0.025 +/- 0.060 -0.040 +/- 0.054 06/20/06 -0.025 +/- 0.020 -0.210 +/- 0.170 -0.062 +/- 0.058 0.000 +/- 0.100 -0.016 +/- 0.063 0.014 +/- 0.035 09/19/06 0.002 +/- 0.022 -0.160 +/- 0.210 -0.004 +/- 0.055 -0.034 +/- 0.081 -0.006 +/- 0.059 0.032 +/- 0.044 11/15/06 -0.008 +/- 0.018 0.060 +/- 0.140 -0.010 +/- 0.036 0.007 +/- 0.055 0.016 +/- 0.072 0.002 +/- 0.027 38 Ag-110m Be-7 Co-58 Co-60 Cr-51 Cs-134 03/23/06 0.005 +/- 0.037 -0.070 +/- 0.200 -0.004 +/- 0.025 -0.010 +/- 0.040 0.060 +/- 0.230 0.011 +/- 0.027 06/20/06 -0.029 +/- 0.030 0.020 +/- 0.160 -0.017 +/- 0.022 0.024 +/- 0.034 0.130 +/- 0.210 -0.027 +/- 0.027 09/19/06 -0.004 +/- 0.037 -0.020 +/- 0.180 -0.011 +/- 0.020 -0.026 +/- 0.030 -0.020 +/- 0.250 0.017 +/- 0.025 11/15/06 -0.005 +/- 0.021 -0.030 +/- 0.130 0.006 +/- 0.018 -0.005 +/- 0.017 -0.090 +/- 0.140 0.000 +/- 0.017 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 03/23/06 -0.023 +/- 0.022 0.052 +/- 0.070 -0.016 +/- 0.065 2.210 +/- 0.750 0.005 +/- 0.019 0.027 +/- 0.022 06/20/06 0.004 +/- 0.021 -0.008 +/- 0.060 0.021 +/- 0.047 1.800 +/- 0.690 -0.001 +/- 0.020 -0.013 +/- 0.027 09/19/06 -0.020 +/- 0.022 -0.007 +/- 0.053 0.044 +/- 0.075 2.230 +/- 0.680 0.009 +/- 0.014 -0.002 +/- 0.029 11/15/06 -0.002 +/- 0.017 0.028 +/- 0.037 -0.011 +/- 0.027 2.680 +/- 0.450 0.005 +/- 0.012 -0.004 +/- 0.013

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 20, Clams (pCi/g Dry) Page 2 of 2 Location Collection Isotope Date 38 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 03/23/06 0.006 +/- 0.023 -0.040 +/- 0.240 -0.012 +/- 0.063 0.020 +/- 0.120 -0.051 +/- 0.053 0.028 +/- 0.043 06/20/06 0.013 +/- 0.026 0.050 +/- 0.230 0.000 +/- 0.060 0.051 +/- 0.098 -0.025 +/- 0.069 -0.001 +/- 0.040 09/19/06 -0.012 +/- 0.028 0.000 +/- 0.220 -0.020 +/- 0.061 0.080 +/- 0.110 0.020 +/- 0.062 -0.023 +/- 0.040 11/15/06 0.003 +/- 0.014 -0.070 +/- 0.140 -0.003 +/- 0.041 0.008 +/- 0.048 0.005 +/- 0.064 0.000 +/- 0.028 39-X Ag-ll0m Be-7 Co-58 Co-60 Cr-51 Cs-134 03/27/06 0.009 +/- 0.022 0.150 +/- 0.160 0.005 +/- 0.019 -0.017 +/- 0.022 0.070 +/- 0.140 -0.004 +/- 0.022 06/21/06 -0.003 +/- 0.029 0.140 +/- 0.160 0.006 +/- 0.020 0.014 +/- 0.022 -0.130 +/- 0.180 0.018 +/- 0.020 08/30/06 0.013 +/- 0.020 0.050 +/- 0.140 -0.002 + 0.013 0.010 +/- 0.018 -0.040 +/- 0.150 0.011 +/- 0.015 12/12/06 0.014 +/- 0.028 0.230 +/- 0.230 -0.004 +/- 0.025 0.002 +/- 0.029 -0.090 +/- 0.280 0.004 +/- 0.028 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 03/27/06 0.004 +/- 0.017 -0.016 +/- 0.045 0.006 +/- 0.025 1.480 +/- 0.540 0.002 +/- 0.019 -0.030 +/- 0.025 06/21/06 0.001 +/- 0.017 0.021 +/- 0.043 0.016 +/- 0.037 2.030 +/- 0.560 -0.017 +/- 0.022 0.012 +/- 0.021 08/30/06 -0.004 +/- 0.015 -0.007 +/- 0.034 0.004 +/- 0.041 5.460 +/- 0.560 -0.002 +/- 0.011 -0.007 +/- 0.018 12/12/06 -0.016 +/- 0.033 0.000 +/- 0.059 -0.054 +/- 0.089 2.440 +/- 0.720 -0.010 +/- 0.021 0.001 +/- 0.033 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 03/27/06 -0.003 +/- 0.020 0.030 +/- 0.170 -0.020 +/- 0.033 -0.043 +/- 0.061 -0.017 +/- 0.051 -0.003 +/- 0.040 06/21/06 0.011 +/- 0.020 -0.070 +/- 0.190 -0.030 +/- 0.053 0.002 +/- 0.082 0.000 +/- 0.044 -0.019 +/- 0.034 08/30/06 -0.001 +/- 0.014 -0.030 +/- 0.130 -0.002 +/- 0.036 0.024 +/- 0.060 -0.024 +/- 0.034 -0.017 +/- 0.028 12/12/06 0.018 +/- 0.027 -0.080 +/- 0.270 0.063 +/- 0.069 0.010 +/- 0.120 0.016 +/- 0.065 0.028 +/- 0.050 40-X Ag-ll0m Be-7 Co-58 Co-60 Cr-51 Cs-134 09/19/06 0.003 +/- 0.032 -0.010 +/- 0.170 0.004 +/- 0.024 0.021 +/- 0.026 -0.010 +/- 0.210 -0.006 +/- 0.024 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 09/19/06 -0.004 +/- 0.020 -0.039 +/- 0.051 -0.043 +/- 0.063 2.070 +/- 0.540 -0.006 +/- 0.022 0.015 +/- 0.028 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 09/19/06 -0.023 +/- 0.025 -0.160 +/- 0.200 -0.034 +/- 0.052 -0.005 +/- 0.067 -0.101 +/-+0.056 0.029 +/- 0.041

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 21, Scallops No data collected during 2006

Dominion Nuclear Connecticrat, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 22, Lobsters (pCi/g Dry) Page I of 2 Location Collection Isotope Date 32 Ag-ll0m Be-7 Co-58 Co-60 Cr-51 Cs-134 01/20/06 0.004 +/- 0.007 0.013 +/- 0.041 0.001 +/- 0.005 0.006 +/- 0.006 0.040 +/- 0.044 0.003 +/- 0.005 05/03/06 0.008 +/- 0.024 -0.060 +/- 0.130 0.002 +/- 0.017 0.005 +/- 0.019 -0.080 +/- 0.140 0.001 +/- 0.020 07/10/06 -0.0240 +/- 0.031 -0.060 +/- 0.200 -0.003 +/- 0.019 -0.016 +/- 0.034 0.080 +/- 0.220 0.039 +/- 0.028 10/31/06 0.001 +/- 0.009 -0.044 +/- 0.055 0.001 +/- 0.007 0.001 +/- 0.007 0.002 +/- 0.069 0.001 +/- 0.007 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 01/20/06 -0.0011 +/- 0.005 0.002 +/- 0.011 -0.001 +/- 0.009 2.060 +/- 0.150 -0.002 +/- 0.005 0.008 +/- 0.006 05/03/06 -0.00)7 +/- 0.020 0.003 +/- 0.036 0.029 +/- 0.029 2.320 +/- 0.490 -0.016 +/- 0.016 -0.006 +/- 0.017 07/10/06 0.016 +/- 0.024 0.000 +/- 0.053 0.037 +/- 0.053 2.050 +/- 0.650 -0.008 +/- 0.023 -0.018 +/- 0.023 10/31/06 0.006 +/- 0.006 -0.011 +/- 0.016 0.008 +/- 0.021 2.440 +/- 0.190 0.005 +/- 0.007 0.000 +/- 0.009 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 01/20/06 -0.004 +/- 0.006 -0.011 +/- 0.048 0.001 +/- 0.012 0.024 +/- 0.020 -0.004 +/- 0.013 -0.003 +/- 0.009 05/03/06 0.0012 +/- 0.017 0.110 +/- 0.160 0.005 +/- 0.043 0.055 +/- 0.071 -0.020 +/- 0.044 -0.001 +/- 0.029 07/10/06 -0.0-14 +/- 0.025 -0.080 +/- 0.210 -0.011 +/- 0.056 -0.093 +/- 0.085 0.014 +/- 0.056 -0.008 +/- 0.041 10/31/06 0.00/0 +/- 0.008 0.034 +/- 0.060 -0.011 +/- 0.017 0.023 +/- 0.033 -0.008 +/- 0.016 -0.002 +/- 0.012 35 Ag-110m Be-7 Co-58 Co-60 Cr-51 Cs-134 01/25/06 -0.014+/- 0.024 0.050+/-0.150 -0.001 +/-0.019 -0.011 +/-0.016 -0.110+/-0.130 0.001 +/-0.019 05/03/06 -0.018 +/- 0.018 0.050 +/- 0.120 -0.010 +/- 0.021 -0.010 +/- 0.022 0.010 +/- 0.130 0.012 +/- 0.019 07/10/06 0.003 +/- 0.027 -0.020 +/- 0.160 0.008 +/- 0.022 0.000 +/- 0.025 -0.020 +/- 0.210 0.003 +/- 0.021 10/31/06 0.002 +/- 0.008 0.009 +/- 0.057 -0.001 +/- 0.006 -0.002 +/- 0.006 0.001 +/- 0.070 0.004 +/- 0.007 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 01/25/06 0.004 +/- 0.016 0.005 +/- 0.040 0.002 +/- 0.024 2.170 +/- 0.610 -0.006 +/- 0.022 -0.013 +/- 0.021 05/03/06 0.04 +/- 0.017 0.011 +/- 0.039 -0.015 +/- 0.025 2.510 +/- 0.540 -0.008 +/- 0.017 -0.001 +/- 0.015 07/10/06 -0.00,7 +/- 0.023 0.050 +/- 0.054 -0.008 +/- 0.046 3.660 +/- 0.730 -0.010 +/- 0.022 0.023 +/- 0.031 10/31/06 -0.002 +/- 0.007 0.001 +/- 0.014 -0.014 +/- 0.022 2.510 +/- 0.190 0.005 +/- 0.006 0.008 +/- 0.008 Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 01/25/06 0.006 +/- 0.018 -0.020 +/- 0.160 -0.020 +/- 0.039 -0.042 +/- 0.070 0.005 +/- 0.050 0.001 = 0.037 05/03/06 -0.023 +/- 0.016 0.040 +/- 0.140 0.039 +/- 0.037 -0.011 +/- 0.068 -0.012 +/- 0.041 -0.013 +/- 0.027 07/10/06 -0.018 +/- 0.027 0.080 +/- 0.230 0.040 +/- 0.044 0.035 +/- 0.078 -0.021 +/- 0.062 0.031 +/- 0.039 10/31/06 0.000 +/- 0.007 -0.020 +/- 0.059 -0.013 +/- 0.016 0.015 +/- 0.031 -0.008 +/- 0.015 0.004 +/- 0.011 37-X Ag-Ur0m Be-7 Co-58 Co-60 Cr-51 Cs-134 01/17/06 -0.0092 +/- 0.006 -0.004 +/- 0.042 0.002 +/- 0.005 -0.003 +/- 0.005 -0.061 +/- 0.048 0.004 +/- 0.006 05/15/06 -0.011 +/- 0.024 -0.040 +/- 0.160 -0.007 +/- 0.017 0.007+/- 0.023 -0.080 +/- 0.160 0.006+/- 0.016 08/09/06 -0.005 +/- 0.019 0.040 +/- 0.130 0.001 +/- 0.014 0.010 +/- 0.024 0.020 +/- 0.130 -0.011 +/- 0.017 11/09/06 0.005 +/- 0.012 -0.036 +/- 0.062 0.004 +/- 0.007 0.002 +/- 0.009 0.000 +/- 0.066 0.003 +/- 0.009 Cs-137 Fe-59 1-131 K-40 Mn-54 Nb-95 01/17/06 0.00S +/- 0.006 0.003 +/- 0.011 0.003 +/- 0.011 2.360 +/- 0.150 -0.001 +/- 0.005 -0.004 +/- 0.006 05/15/06 0.010 +/- 0.021 0.019 +/- 0.046 -0.020 +/- 0.029 2.230 +/- 0.560 -0.015 +/- 0.025 0.016 +/- 0.017 08/09/06 0.008 +/- 0.018 -0.008 +/- 0.041 0.006 +/- 0.026 2.230 +/- 0.520 0.006 +/- 0.016 0.000 +/- 0.018 11/09/06 0.007 +/- 0.009 0.007 +/- 0.018 0.003 +/- 0.012 2.770 +/- 0.270 -0.005 +/- 0.007 0.003 +/- 0.009

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Table 22, Lobsters (pCi/g Dry) Page 2 of 2 Location Collection Isotope Date 37-X Ru-103 Ru-106 Sb-125 Th-228 Zn-65 Zr-95 01/17/06 0.001 +/- 0.005 -0.037 +/- 0.045 0.007 +/- 0.013 0.001 +/- 0.026 0.014 +/- 0.017 -0.002 +/- 0.008 05/15/06 -0.014 +/- 0.019 0.170 +/- 0.160 -0.023 +/- 0.050 -0.046 +/- 0.079 0.000 +/- 0.049 -0.007 +/- 0.034 08/09/06 -0.015 +/- 0.016 0.100 +/- 0.170 0.003 +/- 0.036 0.006 +/- 0.068 -0.041 +/- 0.040 0.014 +/- 0.031 11/09/06 0.004 +/- 0.007 -0.016 +/- 0.075 0.003 +/- 0.019 -0.008 +/- 0.034 0.003 +/- 0.021 0.000 +/- 0.014

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 NOTES FOR DATA TABLES

  1. Collection Dates for Air Particulates and lodines are listed as Monday -

Sunday, however the typical change-out days are on Tuesdays A TLD at location 16C missing, pole was removed by CL&P (see CR 03493)

B Low volume (7745 cubic feet) caused by blown pump fuse and broken fuse holder (see CR-06-04356)

C Low volume (8725 cubic feet) caused by faulty surge suppressor (CR 05337)

D Low volume (980 cubic feet) caused by power outage (CR-06-05332)

E Low volume (9706 cubic feet) caused power outage (CR-06-05332)

F Low volume caused by breaker trips (CR-06-08664)

G Non pasture grass sample (e.g., hay or other feed)

H Not collected in April (locations 1, 10 & 17) since no sample available during that time I Unable to obtain water at location 77X J First Quarter flounder samples (locations 32 & 35) were not available (typically scarce during this time of year)

K First Quarter fish-other sample (location 32 & 35) were not available (typically scarce this time of year)

L First Quarter oyster sample at location 36 not available since winter storm activity caused cage to break

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006

4. DISCUSSION OF RESULTS This section summarizes the results of the analyses on the REMP (Radiological Environmental Monitoring Program) samples. DNC has carefully examined the data throughout the year and has presented in this section all cases where station related radioactivity could be detected. The results are compared with previous environmental surveillance data. Few impacts of the station operation on the environment were observed. Sub-sections contain a description of each particular media or potential exposure pathway.

Naturally occurring nuclides such as Be-7, K-40, and Th-228 were detected in numerous samples. Be-7, which is produced by cosmic processes, was observed predominantly in airborne and vegetation samples. Th-228 results were variable and are generally at levels higher than plant related radionuclides.

Cs-137 and Sr-90 were observed at levels similar to those of past years. The levels of Cs-137 and Sr-90 detected were the result of atmospheric nuclear weapons testing in the 1960's.

4.1 Gamma Exposure Rate (Table 1)

Gamma exposure rate is determined from the integrated exposure measured over a calendar quarter using CaSO 4(Tm) Panasonic model UD-804 ASx thermoluminescent dosimeters (TLDs). In 2000, the TLDs (Victoreen glass bulb CaF 2(Mn)), which historically were used to measure radioactivity around Millstone for over 20 years, were replaced with the Panasonic TLDs.

The dosimeters are strategically placed at a number of on-site locations, as well as at inner and outer off-site locations. Starting in 2001, the collection of TLDs was changed from monthly to quarterly and additional measurement locations were incorporated into the REMP requirements listed in the REMODCM (Radiological Effluent Monitoring and Offsite Dose Calculation Manual). Three more locations were added in mid-2003 to prepare for monitoring the potential effect of ISFSI (Independent Spent Fuel Storage Installation - Dry Cask Storage). Two Dry Cask Containers were loaded in the first quarter 2005. Three more were loaded in mid 2006. The exposure rate measurements at these three locations remains unchanged from the background measurements listed in the last two annual reports (9.5 uR/hour at location 73X, 7.6 uR/hour at location 74X and 6.9 uR/hour at location 75X).

Table 1 lists the exposure rate measurements for all 44 monitored locations. Trends similar to those of past years are apparent. These measurements demonstrate the general variations in background radiation between the various on-site and off-site locations and include gamma exposure from all sources of radioactivity. For example, the Weather Shack (location 02), MP3 Discharge (location 05), Environmental Laboratory (location 08), Bay Point Beach (location 09), Pleasure Beach (location 10),

Corey Road (location 48), and Site Switchyard Fence (location 73) experience higher exposure rates due to their proximity to granite beds and stonewalls. In addition, the Mystic (location 13C) and Ledyard (location 14C) control locations experience relatively higher background exposure rate than the other control locations at Norwich and Old Lyme (locations 15C and 16C). The only appreciable effect seen in the TLD data is that attributable to the variation in the background radiation that is consistent with previous years.

4-1

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Figure 4.1-1 shows a historical trend of TLD exposure rate measurements, comparing an annual average of all indicator TLDs, an annual average of all control TLDs, and the annual average of the two most critical indicator locations which are used to represent the two closest site boundary residences in the North-northwest and Northeast directions. Examination of the average measurements since 1990, shows interesting site changes and site characteristics. For example, the average of all indicator locations for the period when Unit 1 was still in operation (through 1995) display the effects of N-16 BWR turbine building sky-shine to immediate areas onsite. As discussed in previous annual reports, the effects of sky-shine at onsite monitoring stations were increases as high as 6 uR/hr at certain onsite locations. Sky-shine decreased rapidly with distance and was indistinguishable from normal background measurements at even the nearest offsite monitoring stations. Also apparent in Figure 4.1-1 is the replacement of the historical Victoreen TLD monitoring system with the Panasonic system in year 2000.

The difference in response between the two systems is very apparent, with the new Panasonic TLDs reading 15% to 20% lower. This lower response is consistent for all locations, including both indicator and control locations.

The figure also relates the difference in critical indicator locations 1 and 3 and the annual average of all indicator TLDs to the annual average of the control TLDs collected and measured during coincident periods throughout the year. As discussed earlier, the exposure measurements of many indicator locations onsite are influenced by natural background exposure differences caused by the many granite out-croppings typical of the Millstone area. As shown in Figure 4.1-1, the annual average at indicator locations 1 and 3 are slightly higher in gamma exposure rate than the average control gamma exposure rate. This difference is the result of the nearby granite.

Review of the individual quarterly data for all locations indicates that at locations 5 and 8, there seems to be an effect caused by storage of the Unit 2 replaced reactor head.

Beginning in the second quarter of 2005, the dose rate in these areas increased by more than the typical variability for this type of measurement. As expected, this increase has shown a decreasing trend because of radioactive decay. The head was shipped offsite for disposal in the fourth quarter 2006; the measured levels at these two locations have returned to the levels measured prior to the head being placed in the storage area. The largest increase during the storage time interval time was at location 5, which is closer to the replaced reactor head storage area than location 8. Based upon the data, the increase in dose rate averaged approximately 0.8 uR/hour. This would equate to a dose of 10 mrem (for these six quarters). These locations are onsite; dose rates at the site boundary would be significantly less. These resulting site boundary doses are bounded by dose rates from other radwaste storage areas and are discussed in Section 5.

The second quarter result for location 55 (Magonk Point - 1.8 miles ESE) showed an unusual increase. Initial results indicated an approximate 30% increase. Investigation (CR-06-07330) indicated that the calibration factors for the TLD badge that were used at this location had changed; corrected results still indicated an approximate 15% increase which is occasionally seen for this type of measurement.

4-2

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 4.2 Air Particulate Gross Beta Radioactivity (Table 2)

Air is continuously sampled at seven inner ring (0 to 2 miles) locations and one control location (14 miles) and by passing it through glass fiber particulate filters. ,These samples are collected weekly and analyzed for gross beta radioactivity. Results are shown on Figure 4.2-1 and Table 2. Gross beta activity remained at levels similar to that seen over the last decade. Inner and control monitoring locations continue to show no significant variation in measured activities (see Figure 4.2-2). This indicates that any station contribution is not measurable.

4.3 Airborne Iodine (Table 3)

Charcoal cartridges are included at all of the air particulate monitoring stations for the collection of atmospheric iodine. These cartridges are analyzed on a weekly basis for I-131. No detectable levels of 1-131 were seen in the 2006 charcoal samples.

4-3

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Figure 4.2-1 MILLSTONE AIR PARTICULATE pCi/m3 2006 Gross Beta Radioactivity 0.035 I- Control

-ndicator I 0.03 0.025 0.02 0.015 0.01 v---- ...

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Figure 4.2-2 MILLSTONE AIR PARTICULATE pCi/mn3 5 Year Historical Gross Beta Radioactivity 3.50E-02 I0 Indicators Control I 3.OOE-02 2.50E 2.OOE-02 1.50E-02 -....

I .OOE-02 .C C........................

c~

(9- '4 ( ( N ) f 75~~(~.,

z A Z z99 4-4

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 4.4 Air Particulate Gamma (Table 4A-D)

The air particulate samples that are utilized for the weekly gross beta analyses are composited quarterly and analyzed for gamma emitting isotopes. The results, as shown in Tables 4A - 4D, indicate the presence of naturally occurring Be-7, which is produced by cosmic radiation. No other positive results are seen. These analyses indicate the lack of station effects.

4.5 Air Particulate Strontium (Table 5)

Prior to 1989 Table 5 was used for listing the data for measurements of Sr-89 and Sr-90 in quarterly composite air particulate filters. The historical data indicated the lack of any detectable station related activity. Since these analyses are not listed in NUREG 1301, these measurements were discontinued. In the event of widespread station related contamination or other unusual events (such as the 1986 Chernobyl incident), these measurements could be made. Historically, when world events created conditions that caused detectable measurements of these nuclides, there was no difference noted between indicator and control locations. This further confirms that any of the detectable levels for these nuclides were not plant related.

4.6 Soil (Table 6)

Millstone resumed collection of soil as a required media type in 2001. Prior to 2001, it had not been sampled for over fifteen years. These samples were discontinued due to the fact that, previous sample results never indicated any station related detectable activity. Similarly, since 2001, no station detectable activity has been seen in these samples. The results of these samples, allows for the determination of baseline activity levels in soil. This is particularly important for Cs-1 37, since significant levels from past weapons testing fallout remain in the soil. Baseline levels should be useful in the future, when site characterization and decommissioning of the station become the focus during preparations for License termination. This media is collected annually from one control and two indicator locations.

4.7 Cow Milk (Table 7)

Typically, the most sensitive indicator of fission product existence in the terrestrial environment is radiological analysis of milk samples. Since milk is a widely consumed food, it is usually one of the most critical exposure pathways. Since 1996 all dairy (cow) farms close enough to Millstone to be considered an indicator location (i.e.

conservatively within 10 miles since reference 15 specifies 5 miles) have ceased operation. Therefore, the sampling of cow milk has been discontinued until such time dairy activities resume. Each year the Land Use Census is used to identify locations of milk animals that should be included in the monitoring program. It is performed annually and is maintained by observations, door-to-door surveys and consulting with local agriculture authorities. The 2006 census can be seen in Appendix A. If a new dairy farm is identified close enough to Millstone to be considered an indicator location, the collection of cow milk will resume.

4-5

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 4.8 Goat Milk (Table 8)

When available, these samples are collected twice per month during grazing season and once per month during the rest of the year. Each sample is analyzed for 1-131 and gamma emitting nuclides. Although not required by the REMODCM, samples from each location are composited quarterly and analyzed for Strontium.

Goat milk samples are typically a more sensitive indicator of fission products in the terrestrial environment than cow milk samples. It should be noted that the uptake of radionuclides in milk is dependent on a number of parameters. These include:

metabolism of these animals, feeding habits, farming practices and feed type. Similar to previous years, Cs-137 and Sr-90 are observed in goat milk. During past weapons testing periods, samples taken at certain milk locations indicated higher uptake of fallout than others. This was especially apparent in past samples collected in the immediate area around Millstone (see previous Annual Operating Reports). One of these sites, located at 5.2 Mi. NNE of Millstone (previous location 22, sampled from 1994 through 2004), exhibited a trend of showing higher Sr-90 and Cs-137 concentrations than at some of the other locations (including ones closer to Millstone). The station and regulatory authorities have carefully reviewed past and present data. The presence of the Sr-90 and Cs-137 is the result of residual radioactivity deposited into the environment from the fallout of past nuclear weapons testing. The facts that lead to this conclusion are presented in Section 6.0. These facts include: effluent release totals for these isotopes show insufficient quantities to account for such measurements; Sr-89 and Cs-134 which are chemically similar and generally released in comparable quantities were not detected, and a trend since the early 1960's that shows a consistent declining presence of Cs-1 37 and Sr-90 in milk from Connecticut.

The 2006 results indicate no detectable 1-131 in this media. In the 1970's and 1980's low levels of plant related 1-131 were seen in some of these samples. However, for over 17 years, no plant related detectable levels of 1-131 have been seen in goat milk samples. The only other occasions where 1-131 was detected were fallout episodes from the Chinese Weapons Tests of the mid to late 1970's and Chernobyl.

Goat milk was unavailable at all locations both early and late in the year. Per requirements, pasture grass or feed is collected as a substitute when milk is not available (see 4.9. Pasture Grass and Feed).

4.9 Pasture Grass and Feed (Table 9)

When the routine milk samples are unavailable, samples of pasture grass are required as a replacement. These samples may also be taken to further investigate the levels of radioactivity in milk. During the winter months and early spring, insufficient growth often prohibits sampling of pasture grass. Feed (e.g., hay) is typically sampled whenever pasture grass is not available.

No station effects are noted in these samples. Cosmic produced Be-7 was observed in the majority of the pasture grass samples and many of the hay samples. Due to its relatively short half-life (52 days), it was not detected in the several of the "older" hay samples. Naturally occurring K-40 was a factor of two times higher in hay (compared to pasture grass). Similar to goat milk, the Cs-137 values at the indicator and control locations are comparable. This provides an indication that the levels observed are the result of residual weapons testing fallout 4-6

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 4.10 Well Water (Table 10)

These samples were discontinued in 1985, because no detectable station activity was ever observed in these samples. However, based upon lessons learned at other nuclear plants, including several undergoing decommissioning, sampling was resumed at several locations starting in the fourth quarter 2003. Three additional locations were added in 2005 to monitor potential leakage from ISFSI. Due to the heightened sensitivity on this potential pathway, three more locations were added in the fourth quarter of 2006. Consistent with the past data, there still has not been any station activity detected in any of these samples.

4.11 Reservoir Water (Table 11)

Reservoir water samples are special samples not required by the REMP. Previous data has shown the lack of detectable station activity in this media. This fact and the extremely unlikely possibility of observing routine station effluents in this media have resulted in discontinuing these samples. In the event of widespread station related contamination, these samples may be collected.

4.12 Fruits and Veqetables (Table 12)

Consistent with past years, this media did not show any station effects. Naturally occurring K-40 was detected in all samples.

4.13 Broad Leaf Veqetation (Table 13)

Consistent with past years, this media did not show any station effects. Most samples had detectable levels of cosmic produced Be-7, at levels consistent with previous years.

Positive indications of Cs-137 were observed in one sample. This level is comparable to those observed in past years and is due to fallout.

This media can be an early and sensitive indicator of releases from the station for both unplanned releases and normal operations. Therefore, to enhance program-monitoring effectiveness, samples of broadleaf vegetation are collected monthly during the growing season, April - October, even though requirements are to collect this media twice a year.

4.14 Seawater (Table 14)

In the vicinity of discharge (location 32), seawater is normally sampled by using a continuous sampler. A technician collects an aliquot from this sampler on a weekly frequency and composites it for monthly analyses. In September 1999, Millstone increased the required analysis frequency for this composite sample to a monthly basis to increase monitoring effectiveness. For the Control Location, Giants Neck (location 37C), six weekly grab samples are obtained for quarterly compositing. In 2003, the LLD for H-3 (tritium) at the indicator location (32) was lowered by approximately a factor of four to further enhance monitoring effectiveness. This lower LLD was continued through 2006.

4-7

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Naturally occurring K-40 was seen all but two of the samples. Measured plant related levels of H-3 inseawater from the immediate vicinity of discharge (location 32) were observed in 7 of the 12 samples. This sample is taken directly from liquid effluent flow prior to dilution into Long Island Sound. Dilution studies performed for this discharge have determined that a dilution factor of 3 is appropriate to estimate concentrations immediately outside the quarry within a near-field area.

Tritium builds up in the reactor coolant during each fuel cycle. It is generated during plant operation from fission and neutron reactions. Between 1992 and 2002, H-3 was not typically detected. However, due to the enhanced detection sensitivity, H-3 levels are now typically detectable. Figure 4.14-1 shows a thirteen-year trend of H-3 releases in the Millstone liquid effluents versus the measured environmental concentrations from the vicinity of discharge location. As can be noted from the figure, since the restart of Unit 3 in 1998 and Unit 2 in 1999, tritium releases in liquid effluents have risen to levels at, or above, those observed during the pre-shutdown period. The lower LLD enables a direct comparison of effluent monitoring to environmental monitoring for this exposure pathway. Figure 4.14-2 shows this comparison. This comparison is also more accurate than Figure 4.1-1 since it takes into account the dilution flow during each month.

Dilution flow can change substantially during plant outages. By plotting the data monthly, the resolution of the comparison is further enhanced, although there can be slight discrepancies due to the REMP sample not necessarily being on the last day of each month.

Figure 4.14-1 MILLSTONE LIQUID H-3 RELEASE VERSUS SEAWATER CONCENTRATION 1700 13 Year Historical Trend 1600 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 I

300 200 100 0 ) . e -*

C 0 INV 4-8

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Figure 4.14-2 NilLSTONESeawater - Tritium 2006 S ampiles ". Effluent Meas urements 1000

-Fbu ASeawater SanopDes

  • -I-Effluent Measurements 800 600 0

0.

400 200 0

JJan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 4.15 Bottom Sediment (Table 15)

Cs-137 was detected in the samples from Golden Spur (67X). This is typical for this location, since it is a fresh water area. The levels of Cs-137 at this location are comparable to those observed in past river water sediments taken from other areas of the Connecticut River. Because of the relative distance and direction of the Golden Spur location from the station "and comparable levels seen at even much farther locations, the Cs-1 37 detected at Golden Spur is from weapons testing fallout.

Cs-137 was also detected in the extra samples from Jordon Cove Bar (39X). The levels at Jordan Cove Bar are similar to those at Golden Spur and likely exhibit some effect of the fresh water drainage from Jordan Brook. Although these levels may be the result of fallout, the samples from Jordan Cove Bar also indicated detectable quantities of Co-60.

Therefore, some of this detectable Cs-137 in Jordan Cove may be the result of plant operation.

The levels of Co-60 in Jordan Cove are considered plant related activity. Similar levels were noted in 2004 and 2005 and somewhat lower levels in 2003. Prior to 2003, plant related activity has not been detected in bottom sediment for over a decade. The present levels are comparable to the levels observed in 1990. Bottom sediment is not a significant dose pathway to man, especially at areas not typically used by the public.

Examinations of other aquatic media, including seafood, sampled from these locations (discussions that follow) do not show any detectable Co-60 or Cs-1 37. A new location was added near the closest public beach (location 69X). The data for this location did not indicate any plant related activity.

4-9

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 4.16 Aquatic Flora (Table 16)

Although sampling of this media is not required, it provides useful information since it a very sensitive indicator of station discharges. Low levels of activity (e.g., Mn-54, Co-58, Co-60, Zn-65, 1-131 and Ag-11 Om) have been detected in the past. However, since 2000 levels have decreased to undetectable for all nuclides except for 1-131. One positive measurement was noted in 2004, several in 2005 and several more this year.

There has been a decrease in liquid releases from the station, which has caused most of these nuclides to become undetectable. However, seaweed has a significant bioaccumulation factor which makes it an extremely sensitive indicator of iodine in the environment.

Initial investigation of the positive measurement from the September 14, 2005 sample (CR-05-10353) indicated that the 1-131 activity may have been caused by low levels in recent releases. Additional follow-up samples were taken on November 7, 2005, prior to a Unit 2 liquid discharge and on November 8, 2005 after a Unit 2 liquid discharge. These extra samples seemed to confirm the effect from a liquid discharge. The 1-131 levels were quite low and are often hidden within the counting statistics. However, further follow-up in 2006 included sampling in the Thames River and at Rocky Neck to determine if there may have been other sources for the 1-131. These extra samples indicated the most likely cause for the 2004 - 2006 positive 1-131 results was outfall from wastewater (sewage) treatment plants. The usage of 1-131 in medical treatments is becoming more common and it is not unusual for it to be in wastewater. The New London Waste Water Treatment Plant is located on the west side of the Thames River near Fort Trumbull. Groton has two wastewater treatment plants, one located across the Thames River (and slightly upstream) from the New London treatment plant and the other near Bluff Point. Note that the highest 1-131 results are in the samples from the Thames River, which were taken near the outfall from the New London Waste Water Treatment Plant. There was no 1-131 detected in any of the other aquatic (fish and shellfish) samples. No other station potentially related radioactivity was detected in aquatic flora in 2006.

4.17 Fish (Tables 17A and 17B) 4.17.1 Flounder (Table 17A)

The activity in Flounder is the same as that seen for the past decade. No activity was observed except for the naturally occurring nuclides.

4.17.2 Fish - Other (Table 17B)

The activity in other fish is the same as that seen for the past decade. No activity was observed in this media except for naturally occurring nuclides, including samples taken from within the quarry.

4.18 Mussels (Table 18)

Similar to the last several years, this sampling media showed no station related radioactivity at all locations.

4-10

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 4.19 Oysters (Table 19)

All locations, except for the quarry, utilize oysters stocked in trays. The oysters used for stocking these trays been obtained from location 68Z for the last several years. To confirm that the stocked oysters are not initially contaminated, the oysters from location 68Z have also been analyzed. The stocked trays are kept at most of the sampling areas to guarantee samples and facilitate sample collection. Native oysters are sampled at the quarry (location 40X), which is an extra location.

Station related Ag-1 10m was observed in two of the four samples from within the station discharge area (locations 32) and in three of the four samples from the Quarry (40X).

Although location 32 is labeled as the vicinity of discharge, it has actually been located at the end of the quarry until last year when it was moved to a more accessible area in the middle of the quarry to address safety concerns. No station related activity was observed in samples from beyond the station discharge area.

For several previous years, high levels of Zn-65 were observed in oysters. This was caused by their high capacity for accumulating zinc. Studies have shown that oysters can accumulate as much as 50 times or more the amount of zinc compared to most other seafood (Wolfe, 1979). A remarkable correlation existed between the Zn-65 concentration measured in. the native quarry oysters and the amount of Zn-65 discharged into the environment. However, since the permanent shutdown of Millstone Unit 1 in 1996, the amount of Zn-65 in liquid effluents has decreased to being undetectable in the station discharges. Starting in 2001, no Zn-65 has been released in liquid effluents and no Zn-65 has been detected in oysters. Figure 4.19-1, shows the historical trend that existed between Zn-65 releases and measured concentrations in quarry oysters. The decreasing trend in effluent radioactive releases is apparent in both the curies released and the measured concentrations in oysters.

Figure 4.19-2 shows a similar trend of Ag-110m concentration in quarry oysters compared to the liquid effluents discharged. Again, the correlation between Ag-1 1Om discharged and the Ag-110m concentration measured in the native quarry oysters is apparent. The historical sensitivity between station measured effluent discharges of Zn-65 and Ag-110m when compared to environmental measured concentrations has provided a basis for Millstone to adjust the bioaccumulation factors for Zn-65 and Ag-11 Om used in the standard industry effluent dose consequence codes. Section 5 shows a comparison of the two dose methods. (i.e., dose from the station's measured radioactive discharges input into conservative models versus actual measurements of the concentrations of radioactivity in environmental media to calculate annual dose commitment from consumption).

Because no station activity was observed at locations beyond the station discharge area and since the two locations in the quarry are on-site and not available for public use, the actual concentration of the nuclides in oysters available for public consumption is much less. The near-field dilution factor for liquid discharges from the Millstone quarry discharge is a factor of 3. The dose consequence of the station related radioactivity via this pathway is discussed in Section 5.0 4-11

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 4.20 Clams (Table 20)

Occasionally this media indicates the presence of station related radioactivity. No station related radioactivity was observed in any of the clam samples taken in 2006.

4.21 Scallops (Table 21)

Scallops are not required by the REMP. However, attempts are made to sample this media to confirm station effects because scallops are available for public consumption.

No scallop samples have been available for several years.

4.22 Lobsters (Table 22)

Like the last several years, no station related radioactivity was detected in this sample media in 2006.

4-12

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Figure 4.19-1 Zn-65 COMPARISON Curies Conc. (pCilgram)

Curies Discharged vs. Native Oyster Conc.

0.1 100


Curies 0ischarged W- Oyster Cbonc.

0.01 10 0.001- 1 0.0001 0.1 0.00001 0.000001 .

Quarter Figure 4.19-2 Ag-110m COMPARISON Curies Conc. (pCi/gram)

Curies Discharged vs. Native Oyster Conc.

0.1 - 100

-- Curies ischargedo 0.01 i ýýA -I-- Oyster Conc.

.10 0.001 i 1V -1 lwýfýA ?

U 0.0001 - ý* 10.1 0.00001 -0.01 0.000001 - -0.001 9

Quarter 4-13

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006

5. OFFSITE DOSE EQUIVALENT COMMITMENTS The off-site dose consequences (dose equivalent commitments) of the station's radioactive liquid and airborne effluents have been evaluated using two methods.

The first method utilizes calculations of direct dose from sources onsite and the station's measured radioactive discharges as input parameters into conservative models to simulate the transport mechanism through the environment to man. This results in the calculation of the maximum dose consequences to individuals. The results of these computations have been submitted to the NRC in the Radioactive Effluent Release Report written in accordance with the Radiological Effluent Monitoring and Offsite Site Calculation Manual,Section I.F.2. This method, which is usually conservative (i.e., computes higher doses than that which actually occur), has the advantage of approximating an upper bound to the dose consequences. This is important in those cases where the actual dose consequence cannot be measured because they are so small as to be well below the capabilities of conventional monitoring techniques.

The second method utilizes the actual measurements of the concentrations of radioactivity in various environmental media (e.g., fish, shellfish) and then computes the dose consequences resulting from the consumption of these foods.

The results of both methods are compared in Table 5.1 for those pathways where a potential dose consequence exists and a comparison is possible. The doses presented in this table are calculated at the location of maximum effect from the station effluents for that pathway and for the critical age group. For example, the external gamma dose from gaseous effluents is calculated for the site boundary location which is not only the nearest but also has the greatest directional wind frequency and fish and shellfish doses are calculated assuming they are from an area within 500 feet of the station discharge.

Summarizing the data in Table 5.1:

MAXIMUM TOTAL INDIVIDUAL DOSES: WHOLE BODY = 0.24 mrem GI(LLI) 0.022 mrem Thyroid = 0.071 mrem The majority of the whole body dose is due to a conservative determination of dose (-0.22 mrem) to the nearest resident as a result of direct radiation from on-site radioactive waste operation/storage facilities and continuous occupancy. The GI(LLI) dose is essentially all attributable to the liquid pathway based upon Method 2. The thyroid dose is based upon conservative assessments using Method 1.

Since the maximum dose consequence to an individual is at the location of highest dose consequence, doses will be less for all other locations. The average whole body dose to an individual within 50 miles historically is on the order of 1000 times less than the maximum individual whole body dose.

In order to provide perspective on the doses in Table 5.1, the standards on the allowable maximum dose to an individual of the general public are given in 40CFR190 as 25 mrem whole body, 75 mrem thyroid, and 25 mrem to any other organ. These standards are a fraction of the normal background radiation dose of approximately 284 mrem per year and are designed to be inconsequential in regard to public health and safety. Since station related doses are even a smaller fraction of natural background, they have insignificant public health consequences. In fact, the station related doses to the maximum individual are less than 10%

of the variation in natural background in Connecticut.

5-1

2Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 TABLE 5.1 COMPARISON OF DOSE CALCULATION METHODS MILLSTONE POWER STATION 2006 Annual Dose (millirem)

Method 1 Mthod .2(

Pathway Individual Organ Unit I Unit 2 Unit 3 Station Station (BWR) (PWR) (PWR) Total Airborne Effluents Max(2) Whole Body 0.0000 0.00379 0.00020 0.0040 ND(3)

1. External Gamma Dose (gamma air)(8)
2. Whole Body Dose Max~2 ) Whole Body 0.00098 0.0101 0.0123 0.023 ND (internal and external)
3. Inhalation, vegetables and Max(2) Thyroid 0.00095 0.0581 0.0123 0.0714 ND goat milk Direct Dose Nearest Residence Max(2) Whole Body N/A N/A N/A -0.22(') ND(5) 5-2

3Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 TABLE 5.1 (Cont.)

COMPARISON OF DOSE CALCULATION METHODS MILLSTONE POWER STATION 2006 Annual Dose (millirem)

Max -Method 1 ( Method 2!'i Pathway Individual Organ Unit 1 Unit 2 Unit 3 Station Station (BWR) (PWR) (PWR) Total Liquid Effluents

1. Fish
  • Adult Whole Body 0.000000 0.000222 0.000174 0.000396 ND(3)

Teen 0.000000 0.000181 0.000149 0.000330 Child 0.000000 0.000164 0.000148 0.000313

  • Adult GI(LLl)(6) 0.000000 0.001457 0.000438 0.001895 ND Teen 0.000000 0.001044 0.000326 0.001369 Child 0.000000 0.000431 0.000163 0.000594 Adult Liver 0.000000 0.000328 0.000310 0.000638 ND
  • Teen 0.000000 0.000301 0.000296 0.000598 Child 0.000000 0.000270 0.000275 0.000546
2. Shellfish
  • Adult Whole Body 0.000000 0.000117 0.000114 0.000231 0.000026(')

Teen 0.000000 0.000110 0.000112 0.000223 0.000027 Child 0.000000 0.000125 0.000136 0.000261 0.000030

  • Adult GI(LLI) 0.000000 0.001346 0.000699 0.002045 0.0181 (7)

Teen 0.000000 0.000903 0.000502 0.001445 0.0124 Child 0.000000 0.000359 0.000199 0.000558 0.0044 Adult Liver 0.000000 0.000262 0.000316 0.00578 0.000044(7)

  • Teen 0.000000 0.000266 0.000329 0.00595 0.000044 Child 0.000000 0.000259 0.000330 0.00589 0.000037 5-3

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Notes:

1. Except for direct dose, method 1 uses measured station discharges and meteorological data as input parameters to transport-to-man models that conservatively calculate dose to people; method 2 uses actual measured concentrations in environmental media to estimate the dose.
2. Maximum individual - The maximum individual dose is the dose to the most critical age group at the location of maximum concentration of station related activity. The dose to the average individual is much less than the maximum individual dose.
3. ND - Not Detectable - No station related activity could be detected above natural background or above the minimum detectable level (MDL).
4. The dominant source of direct dose from the station is from storage and movement of radioactive waste. Storage of radioactive waste is allowed in several areas onsite.

Operation of the storage facilities is limited by design to ensure that the maximum direct dose at the site boundary from each area does not exceed one millirem. Actual exposure throughout the year was maintained much less than this operational limit. Each facility is monitored onsite by the Radiation Protection Department using TLDs. The exposure measured for each facility TLD was corrected for distance to the nearest site boundary residence. The resultant exposure was conservatively multiplied by 1.5 to account for sky-shine. These maximum estimated doses from each facility were summed for a cumulative site commitment of approximately 0.22 millirem. The whole body dose from airborne effluents was 0.023 and from liquid effluents was 0.00075. This results in a total estimated whole body dose to the maximum individual of 0.24 mrem (0.22 + 0.023 + 0.000715).

5. Measured dose was derived from monthly TLD readings. There are two residences that qualify as the closest residence; each has a TLD near enough to use as an estimate to each residence. The one with the highest average dose rate was used to estimate the direct dose to the closest residence. A background dose rate was subtracted. This background was derived from the average of the five control TLD locations. This method is very conservative assuming natural exposure influences, such as granite, are actually plant related exposure. This method provides a bounding high value. The exposure measurements of the select indicator locations are influenced by natural background exposure differences caused by the many granite out-croppings typical of the Millstone area. Historical data has shown that TLD sample locations in the vicinity of granite can be dramatically influenced by natural radioactivity contained within the granite.
6. GI (LLI) - Gastrointestinal Tract - Lower Large Intestine.
7. Based on measured levels in quarry oysters. A measured near field dilution factor of 3 was used to adjust for the fact that these oysters are on-site and inaccessible to the public. This factor adjusts the measured on-site concentration to that which could occur to a public accessible off-site location after dilution of the effluent by the Long Island Sound.
8. Based upon the conservatively assuming no correction for building shielding and occupancy.

5-4

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006

6. DISCUSSION The evaluation of the effects of station operation on the environment requires the careful consideration of many factors. Those factors depend upon the media being affected. They include station release rates, effluent dispersion, occurrence of nuclear weapons tests, seasonal variability of fallout, local environment, and locational variability of fallout. Additional factors affecting the uptake of radionuclides in milk include soil conditions (mineral content, pH, etc.),

quality of fertilization, quality of land management (e.g., irrigation), pasturing habits of animals, and type of pasturage. Any of these factors could cause significant variations in the measured radioactivity. A failure to consider these factors could cause erroneous conclusions.

Consider, for example, the problem of deciphering the effect of station releases on the radioactivity measured in milk samples. This is an important issue because this product is widely consumed and several fission products readily concentrate in this media. Some of these fission products, such as 1-131 and Sr-89 are relatively short-lived. Therefore they can result from either station effluents, nuclear weapons tests or nuclear incidents (e.g. Chernobyl).

Sr-89's lifetime is longer than 1-131's, therefore it will remain around for much longer periods of time. The even longer-lived fission products, Sr-90 and Cs-137, cause more of a concern.

These isotopes are still remaining from the weapons testing era of the 1960's. This results in measurable amounts of Sr-90 and Cs-137 appearing in some milk samples. Distinguishing between this "background" of fallout activity and station effects is of prime interest for a Radiological Environmental Monitoring Program.

In reviewing the historical and present Sr-90 and Cs-137 measured in cow and goat milk in the areas around Millstone station, a casual observer could notice that in some cases the levels of these isotopes are higher at farms closer to the station than at those further away from the station. The station's effluents -might at first appear to be responsible. However, the investigation of the following facts proves this conclusion wrong.

(1) The stations accurately measure many fission products, including Sr-90 and Cs-137 in their releases. Based on these measurements and proven models developed by the Nuclear Regulatory Commission, concentrations in the environment can be calculated. These calculations (generally conservative, see Section 5.0) show that insufficient quantities of Sr-90 and Cs-137 have been released from the plants to yield the measured concentrations in milk.

(2) Over the many years of station operation, Sr-89 has often been released in comparable quantity to Sr-90. Since they are chemically similar, comparable levels should have been detected in milk if the Sr-90 was station related. No station related Sr-89 has ever been detected in milk samples.

(3) Similar to Sr-89, Cs-134 can be used as an indication of station related Cs-137. Although not as conclusive as Sr-89, the lack of any measurable Cs-134 in any of the milk samples suggests that the Cs-1 37 is not station related. This is further confirmed by the evaluation of the air particulate data. The only occurrences of detectable Cs-1 34 in milk resulted from the Chernobyl incident.

(4) Dairy milk sampling in Connecticut began in the 1960's, several years prior to nuclear station operation. The highest levels of weapons fallout related Sr-90 and Cs-137 (see Figures 6-1 and 6-2), were measured in the years prior to station operation. Samples taken in the immediate station areas have always shown higher levels of weapons related fallout than samples taken from the Central Connecticut Region (CT Pooled Milk). Radioactivity levels of fallout related Sr-90 and Cs-137 have decreased significantly since the 1964 Nuclear Test Ban Treaty due to decay.

6-1

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 (5) Local variability of Sr-90 and Cs-1 37 in milk is common throughout the United States. Due to the variability in soil conditions, pasturing methods, rainfall, etc., it is the rule rather than the exception. Therefore, it is not surprising that certain farms have higher levels of radioactivity than other farms. In fact, in the past there are some cases where the farms further from the station have higher Sr-90 and Cs-1 37 values than the farms that are closer to the station.

(6) In the past when a goat farm operated near Millstone (2.0 Mi - ENE), the highest levels of Sr-90 and Cs-137 were typically indicated. This same farm also experienced the highest levels of short-lived activity from the 1976 and 1977 Chinese Tests and the 1986 Chemobyl accident. This indicates that for some unknown reason this farm had the ability for higher reconcentration. Special studies performed at this and other farms failed to find any link to the station.

Based on these facts, the observation that the station effluents are responsible is obviously false. The cause must be one or more of the other variables.

Dominion has carefully examined the data throughout the years and has presented in this report all cases where station related radioactivity could be detected. An analysis of the potential exposure to the maximum individual from any station related activity has been performed and shows that in all cases the exposure is insignificant.

The Connecticut Department of Environmental Protection (DEP) performs an independent check on certain environmental program analyses. The results of their analyses are comparable to the results from this program's analyses. These comparisons can be used as a cross-reference to verify measured station activity. DEP performed a comprehensive review of all the historical Millstone data in 2006 (reference 17). It concluded that "the collective sampling in and around Millstone Power Station show expected levels of residual fallout from weapons testing and the Chernobyl event and are unrelated to the operation of the Millstone Power Station."

Figure 6-1 Strontium-90 in Milk pC1/liter 25- 25 --.e-- CT Pooled W~ik 20- Haddam area Wk area Mik 15-Mlstone 10-5 01 61 63 65 67 69 71 73 75 77 79 81 83 85 87 89 91 93 95 97 99 Year 6-2

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 Figure 6-2 Cesium-137 in Milk 1 Wi/liter 140 ---CT Pooled Milk 120 m Haddam area Milk 100 A Millstone area Milk 80 60 40 20 0

61 63 65 67 69 71 73 75 77 79 81 83 85 87 89 91 93 95 97 99 Year Dairy milk is no longer available in the Millstone area, Haddam Neck no longer collects milk, and CT Pooled milk has not been collected by the State of CT since 1994. Graphs provided to show historical trends.

CY Start-up occurred: July 24,1967 MP2 Start-up occurred: December, 1975 MP1 Start-up occurred: October 26,1970 MP3 Start-up occurred: January 23,1986 6-3

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006

7. REFERENCES
1) United States of America, Code of Federal Regulations, Title 10, Part 50, Appendix A Criteria 64.
2) Donald T. Oakley, "Natural Radiation Exposure in the United States." U. S. Environmental Protection Agency, ORP/SID 72-1, June 1972.
3) National Council on Radiation Protection and Measurements, Report No. 93, "Ionizing Radiation Exposures of the Population of the United States," September 1987.
4) National Council on Radiation Protection and Measurements, Report No. 94, "Exposure of the Population of the United States and Canada from Natural Background Radiation,"

December 1987.

5) United States Nuclear Regulatory Commission, Regulatory Guide 8.29, "Instructions Concerning Risks from Occupational Radiation Exposure," Revision 0, July 1981.
6) Millstone Training Brochure.
7) United States Nuclear Regulatory Commission, Regulatory Guide 1.109, "Calculation of Annual Doses to Man from Routine Releases of Reactor Effluents for the Purpose of Evaluating Compliance with 10 CFR Part 50, Appendix I," Revision 1, October 1977.
8) Millstone Power Station Radiological Effluent Monitoring and Offsite Dose Calculation Manual, Revision 025-02, December 2006.
9) United States of America, Code of Federal Regulations, Title 10, Part 20.1301.
10) United States of America, Code of Federal Regulations, Title 10, Part 50, Appendix I.
11) United States of America, Code of Federal Regulations, Title 40, Part 190.
12) United States Nuclear Regulatory Commission, Regulatory Guide 4.1, "Program for Monitoring Radioactivity in the Environs of Nuclear Power Plants," Revision 1, April 1975.
13) ICN/Tracerlab, "Millstone Nuclear Power Station Pre-operational Environmental Radiation Survey Program, Quarterly Reports," April 1967 to June 1970.
14) International Commission of Radiological Protection, Publication No. 43, "Principles of Monitoring for the Radiation Protection of the Population," May 1984.
15) United States Nuclear Regulatory Commission, NUREG-1301, "Offsite Dose Calculation Manual Guidance: Standard Radiological Effluent Controls for Pressurized Water Reactors," April 1991.
16) United States Nuclear Regulatory Commission, Branch Technical Position, "An Acceptable Radiological Environmental Monitoring Program," Revision 1, November 1979.
17) Reassessment of Millstone Power Station's Environmental Monitoring Data, Connecticut Department of Environmental Protection, Division of Radiation, March 2006.

7-1

APPENDIX A LAND USE CENSUS FOR 2006 A-1

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 TABLE A-1 Dairy Cows Within 20 miles of Millstone Point- 2006 Direction Distance Location # of Cows N 14 Miles Preston 60*

N 20 Miles Norwich 220*

NNE 16 Miles Preston 65*

NNE 16 Miles Norwich 25*

NNE 16.5 Miles Preston 55 NNE 17 Miles Preston 126 NNE 19 Miles Preston 50 NE 13.5 Miles Ledyard 50 NE 18 Miles Preston 50 NE 18 Miles North Stonington 65 NE 19 Miles North Stonington 49 ENE 17.3 Miles North Stonington 280 ENE 20 Miles North Stonington 330 WNW 10.5 Miles Lyme 69 NW 10.4 Miles Lyme 10"*

Note: No cow farms on this list are used for sampling, all farms are greater than ten miles from plant.

  • unknown (based upon 2005 census)
    • sheep A-2

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 TABLE A-2 Dairv Goats Within 20 miles of Millstone Point- 2006 Direction Distance Sample Location # of Goats N 2.4 Miles Waterford (LOCATION 21) 7/4*

N 20 Miles North Franklin 2/2 NE 2.7 Miles Waterford (LOCATION 22) 12/0 ENE 2 Miles Waterford 1/0 ENE 13 Miles Stonington 7/2 ENE 16.2 Miles North Stonington 3/0 WNW 5.1 Miles Niantic WNW 18 Miles Haddam 6/3 NW 17.3 Miles East Haddam 6/2 NNW 12.3 Miles Salem 12/6 NNW 18 Miles Colchester 37/20 NNW 20.8 Miles Colchester 6/3 NNW 29 Miles Hebron (LOCATION 24) 70/26

  • Number of Goats/Number of Milkers
    • Unable To Contact As Of This Time A-3

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 TABLE A-3 2006 Resident/Garden Survey Distance to Distance to Downwind Closest Closest Garden Direction Resident (meters)

(meters)

N 1500 1490 NNE 860 820 NE 790 800 ENE 1590 1620 E 1500 1670 ESE 1690 1990 SE SSE S

SSW SW 3700 3840 WSW 3190 35500 W 2870 2950 WNW 2470 2740 NW 770 2180 NNW 740 1020

  • N/A - not applicable (over water sectors)

A-4

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 APPENDIX B DNC QA PROGRAM B-1

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 INTRODUCTION Dominion Nuclear Connecticut (DNC) maintains an independent non-required quality assurance (QA) program as part of the radiological environmental monitoring program (REMP). The QA program consists of contractor appraisals and quality control samples.

This independent program is applicable to all Dominion nuclear facilities because they share a joint contract with Framatome ANP DE&S Environmental Laboratory.

DNC QA PROGRAM The DNC independent QA Program includes spikes of various sample media and duplicate samples. Sample spikes are a check on the accuracy of results of the contractor's radioanalyses. Duplicate samples tests the contractor's precision, or reproducibility of results, by comparing analytical results of split samples. The number and type of DNC QA Program quality control samples are defined in Millstone Nuclear Power Station Health Physics Operations Procedure REMP 1.4, "Quality Control of Radiological Environmental Monitoring Program." An investigation is conducted on any result or trend that does not satisfy acceptance criteria.

OTHER QA PROGRAMS The DNC Independent QA Program is not the only QA Program which monitors REMP radioanalysis performance. Other programs include:

1. Contractor lab's internal QA program. In addition to the Millstone quality control samples, the radioanalysis contractor has its own quality control samples. In total, at least five percent of the contractor's sample analyses include quality control samples.
2. Contractor lab's interlaboratary comparison program with an independent third party, Analytics, Inc. Results of the Analytics intercomparison are contained in Appendix C.

Primary contractor participation in an interlaboratory comparison program is required by station Technical Specifications. The Analytics comparison satisfies this requirement.

3. Contractor lab's participation in the National Institute of Standards and Technology (NIST)

Measurement Assurance Program (MAP), the Environmental Resource Associates (ERA)

Proficiency Test (PT) Program, the Department of Energy (DOE) Quality Assessment Program (QAP), and the Mixed Analyte performance Evaluation Program (MAPEP). The lab participates in these interlaboratory QA programs because of other clients' needs, not because of nuclear power station environmental sample analyses. However, some of these intercomparison samples are also applicable to nuclear power environmental samples.

B-2

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 RESULTS OF MILLSTONE QA PROGRAM FOR CONTRACTOR RADIOANALYSES Criteria for passing QA sample analysis is that the result be within 20% of the known spike except in the case of Sr-89 or Sr-90 spikes in milk which have to be within 30% of the known spike. To allow more tolerance for lower activity spikes an alternate criterion may be used. If the two sigma error range of the analyzed result includes the known spike value the result passes.

The Millstone QA Program indicated that the contractor lab's environmental radiological analysis program was adequate in 2006. Results are shown on Table 2. All of the TLD spike tests satisfied the procedural criteria. Of the 50 individual nuclide analysis results on QA samples, 46 passed the acceptance criteria, a 92% success rate. Of the 4 failures, 3 were low by 26 - 34% and one was low by 47%. This is consistent with last year's results.

B-3

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 TABLE 1 91)OAl ni lIAI ITV r-.tIMTIrAI Q1 TLD Spike 16 (Note 2) 160 Milk - Strontium 2 12 Milk - Iodine 5 Milk - Gamma (Note 3) -30 Pasture Grass/Hay - Gamma (Milk 0 -30 Substitute)

Water - Gamma 4 28 Water - Tritium 4 28 Fish/Invertebrate - Gamma 4 80 Vegetation/Aquatic 0 81 Flora/Sediment/Soil - Gamma Air Particulate - Gross Beta 3 416 Iodine 4 416 Gamma 1 32 FOOTNOTE (Table 1):

1. All samples are spikes except fish/invertebrate which are duplicate oyster samples.

Does not include January 2006 since those results were included in the 2005 report.

2. A set of four TLDs are spiked quarterly for readout during the routine quarterly readout.
3. Gamma in water QA spikes are treated as milk surrogates.

B-4

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 TABLE 2 IALITY CONTROL SAMPLE ANALYSES I L-LisJi.IIX II T Milk - Strontium 4 0 Milk - Iodine 2 3 (Note 2)

Water - Gamma 20 (Note 1) 1 Water - Tritium 4 0 Oysters - Gamma 4 0 Air Particulate - Gross Beta 3 0

- Iodine 4 0

- Gamma 5 0 TOTALS TLDs: 12 TLDs: 0 Individual Nuclides: Individual Nuclides: 4 46 FOOTNOTE (Table 2):

1. To provide a more detailed comparison of pass versus failure, each nuclide was considered for the gamma and strontium analyses.
2. These ranged from 26 to 34 percent low.

B-5

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 APPENDIX C

SUMMARY

OF INTERLABORATORY COMPARISONS C-1

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 INTRODUCTION This appendix covers the Intercomparison Program of the AREVA-NP Environmental Laboratory as required by technical specifications for each Millstone unit. AREVA-NP uses QA/QC samples provided by Analytics, Inc to monitor the quality of analytical processing associated with the Radiological Environmental Monitoring Program (REMP). The suite of Analytics QA/QC samples are designed to be comparable with the pre-1996 US EPA Interlaboratory Cross-Check Program in terms of sample number, matrices, and nuclides. It was modified to more closely match the media mix presently being processed by AREVA-NP and includes:

" milk for gamma (10 nuclides) and low-level (LL) Iodine-131 analyses once per quarter

  • water for gamma (10 nuclides) and low-level (LL) Iodine-131 analyses during the 1st and 3rd quarters
  • water for Sr-89 and Sr-90 analyses during the 1st and 4th quarters
  • water tritium analysis during the 2nd and 4th quarters
  • air filter for gamma (9 nuclides) analyses during the 2nd quarter
  • air filter for gross beta analysis during the 1st and 3rd quarters
  • charcoal filter for 1-131 during the 1st and 3rd quarters

" air filter for Sr-89 and Sr-90 analyses during the 2nd and 4th quarters In addition to the Analytics Intercomparison Program, AREVA-NP also participates in other intercomparsion programs which include radionuclides and media similar to those required by the Millstone program. These programs are the National Institute of Standards and Technology (NIST) Measurement Assurance Program (MAP), the Environmental Resource Associates (ERA) Proficiency Test (PT) Program, the Department of Energy (DOE) Quality Assessment Program (QAP), and the Mixed Analyte Performance Evaluation Program (MAPEP).

RESULTS Intercomparison program results are evaluated using AREVA-NP's internal bias acceptance criterion. The criterion is defined as within 25% of the known strontium value for samples containing both Sr-89 and Sr-90 and within 15% of the known value for other radionuclides, or within two sigma of the known value. Any sample analysis result which does not pass the criteria is investigated by AREVA-NP.

Analytics Intercomparison Program results are included on pages C-3 through C-6 for 2006.

Since the Fourth Quarter Analytics results are not usually available until mid April, the previous year's results are listed. A total of 111 analysis results were obtained with 112 passing criteria, a 99% success rate.

C-2

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 AREVA NP ENVIRONMENTAL LABORATORY ANALYTICS RADIOLOGICAL ENVIRONMENTAL CROSS-CHECK PERFORMANCE EVALUATION E4836-162 4th/2005 Water H-3 DCi/L 13700 13200 1.04 E4837-162 4th/2005 Water Sr-89 pCi/L 80.3 91.4 0.88 E4837-162 4th/2005 Water Sr-90 pCi/L 7.18 7.4 0.97 E4838-162 4th/2005 Filter Gross Alpha pCi 22.3 25.0 0.89 E4838-162 4th/2005 Filter Gross Beta pCi 146 136 1.07 E4839-162 4th/2005 Filter Ce-141 pCi 122 131 0.93 E4839-162 4th/2005 Filter Cr-51 pCi 113 113 1.00 E4839-162 4th/2005 Filter Cs-134 pCi 48.0 51.0 0.94 E4839-162 4th/2005 Filter Cs-1 37 pCi 111 111 1.00 E4839-162 4th/2005 Filter Co-58 pCi 44.2 45.2 0.98 E4839-162 4th/2005 Filter Mn-54 pCi 93.5 88.9 1.05 E4839-162 4th/2005 Filter Fe-59 pCi 44.6 48.1 0.93 E4839-162 4th/2005 Filter Zn-65 pCi 95.8 89.9 1.07 E4839-162 4th/2005 Filter Co-60 pCi 59.1 64.6 0.91 E4840-162 4th/2005 Filter Sr-89 pCi 103 121 0.85 E4840-162 4th/2005 Filter Sr-90 pCi 9.05 9.70 0.93 E4841-162 4th/2005 Milk 1-131LL pCi/L 72.4 74.6 0.97 E4841-162 4th/2005 Milk 1-131 pCi/L 74.1 74.6 0.99 E4841-162 4th/2005 Milk Ce-I 41 pCi/L 217 224 0.97 E4841-162 4th/2005 Milk Cr-51 pCi/L 190 193 0.98 E4841-162 4th/2005 Milk Cs-134 pCi/L 86.4 87.3 0.99 E4841-162 4th/2005 Milk Cs-137 pCi/L 187 189 0.99 E4841-162 4th/2005 Milk Co-58 pCi/L 78.7 77.5 1.02 E4841-162 4th/2005 Milk Mn-54 pCi/L 153 152 1.01 E4841-162 4th/2005 Milk Fe-59 pCi/L 87.8 82.4 1.07 E4841-162 4th/2005 Milk Zn-65 pCi/L 148 154 0.96 E4841-162 4th/2005 Milk Co-60 pCi/L 106 ill 0.95 E4879-162 4th/2005 Charcoal 1-131 pCi 68.4 72.0 0.95 C-3

Dominion Nuclear Connecticut, Inc. Annual Radiological Environrmental Operating Report Millstone Station 2006 AREVA NP ENVIRONMENTAL LABORATORY ANALYTICS ENVIRONMENTAL CROSS CHECK PROGRAM PERFORMANCE EVALUATION E4884-162 lst/2006 Water Gross Alpha pCi/L 38.7 38.1 1.02 E4884-162 lst/2006 Water Gross Beta pCi/L 265 262 1.01 E4885-162 1st/2006 Water I-131LL pCi/L 65.8 67.4 0.98 E4885-162 1st/2006 Water 1-131 pCi/L 66.3 67.4 0.98 E4885-162 1st/2006 Water Ce-1 41 pCi/L 83.0 86.8 0.96 E4885-162 1st/2006 Water Cr-51 pCi/L 217 234 0.93 E4885-162 1st/2006 Water Cs-134 pCi/L 91.9 101 0.91 E4885-162 lst/2006 Water Cs-137 pCi/L 73.3 74.3 0.99 E4885-162 1st/2006 Water Co-58 pCi/L 84.7 87.5 0.97 E4885-162 1st/2006 Water Mn-54 pCi/L 74.7 78.1 0.96 E4885-162 1st/2006 Water Fe-59 pCi/L 73.2 72.4 1.01 E4885-162 1st/2006 Water Zn-65 pCi/L 146.7 148 0.99 E4885-162 1st/2006 Water Co-60 pCi/L 102.5 107 0.96 E4886-162 lst/2006 Water Sr-89 pCi/L 82.0 99.4 0.82 E4886-162 1st/2006 Water Sr-90 pCi/L 10.2 10.8 0.94 E4887-162 1st/2006 Charcoal 1-131 pCi 84.3 84.8 0.99 E4888-162 lst/2006 Filter Gross Alpha pCi 13.5 14.2 0.95 E4888-162 1st/2006 Filter Gross Beta pCi 104.5 97.3 1.07 E4889-162 1st/2006 Milk 1-131LL pCi/L 81.8 78.0 1.05 E4889-162 1st/2006 Milk 1-131 pCi/L 77.4 78.8 0.98 E4889-162 1st/2006 Milk Ce-141 pCi/L 101 104 0.97 E4889-162 lst/2006 Milk Cr-51 pCi/L 277 280 0.99 E4889-162 1st/2006 Milk Cs-134 pCi/L 113.8 121 0.94 E4889-162 lst/2006 Milk Cs-137 pCi/L 86.7 88.8 0.98 E4889-162 1st/2006 Milk Co-58 pCi/L 100 105 0.95 E4889-162 1st/2006 Milk Mn-54 pCi/L 94.6 93.3 1.01 E4889-162 1st/2006 Milk Fe-59 pCi/L 90.7 86.6 1.05 E4889-162 1st/2006 Milk Zn-65 pCi/L 172.2 176 0.98 E4889-162 1st/2006 Milk Co-60 pCi/L 125.0 128 0.98 E4890-162 1st/2006 Milk Sr-89 pCi/L 79.7 99.2 0.80 E4890-162 lst/2006 Milk Sr-90 pCi/L 10.6 10.8 0.98 C-4

Dominion Nuclear Connecticut, Inc. Annual Radiological Environmental Operating Report Millstone Station 2006 AREVA NP ENVIRONMENTAL LABORATORY ANALYTICS RADIOLOGICAL ENVIRONMENTAL CROSS-CHECK PERFORMANCE EVALUATION E5013-162 2nd/2006 Water H-3 pCi/L 5830 6000 0.97 E5014-162 t 2nd/2006 Filter +

Gross AIirha DCi 31.8 36.6 0.87 E5014-162 2nd/2006 Filter Gross Beta pCi 103.8 96.8 1.07 E5015-162 2nd/2006 Filter Ce-1 41 pCi/L 91.6 92.8 0.99 E5015-162 2nd/2006 Filter Cr-51 pCi/L 131.7 131 1.01 E5015-162 2nd/2006 Filter Cs-1 34 pCi/L 60.5 63.9 0.95 E5015-162 2nd/2006 Filter Cs-1 37 pCi/L 62.9 59.3 1.06 E5015-162 2nd/2006 Filter Co-58 pCi/L 52.0 50.6 1.03 E5015-162 2nd/2006 Filter Mn-54 pCi/L 74.5 73.9 1.01 E5015-162 2nd/2006 Filter Fe-59 pCi/L 46.4 47.3 0.98 E5015-162 2nd/2006 Filter Zn-65 pCi/L 93.4 93.6 1.00 E5015-162 2nd/2006 Filter Co-60 pCi/L 63.0 65.0 0.97 E5016-162 2nd/2006 Filter Sr-89 DCi/L 146.6 163 0.90 E5016-162 2nd/2006 Filter Sr-90 pCi/L 7.01 12.3 0.57 E5017-162 2nd/2006 Milk 1-131LL pCi/L 67.0 63.2 1.06 E5017-162 2nd/2006 Milk 1-131 pCi/L 62.0 63.2 0.98 E5017-162 2nd/2006 Milk Ce-141 pCi/L 180.8 184 0.98 E5017-162 2nd/2006 Milk Cr-51 pCi/L 248.0 259 0.96 E5017-162 2nd/2006 Milk Cs-134 pCi/L 120.1 127 0.95 E5017-162 2nd/2006 Milk Cs-137 pCi/L 117.3 117 1.00 E5017-162 2nd/2006 Milk Co-58 pCi/L 97.3 100 0.97 E5017-162 2nd/2006 Milk Mn-54 pCi/L 150.5 146 1.03 E5017-162 2nd/2006 Milk Fe-59 pCi/L 95.4 93.6 1.02 E5017-162 2nd/2006 Milk Zn-65 pCi/L 183.9 185 0.99 E5017-162 2nd/2006 Milk Co-60 pCi/L 126.2 129 0.98 C-5

Dominion Nuclear Connecticut, Inc. Annual Radiological Environr mental Operating Report Millstone Station 2006 AREVA NP ENVIRONMENTAL LABORATORY ANALYTICS ENVIRONMENTAL CROSS CHECK PROGRAM PERFORMANCE EVALUATION E5090-162 3rd /2006 Water Gross Alpha pCi/L 71.5 69.4 1.03 E5090-162 3rd /2006 Water Gross Beta pCi/L 253 273 0.93 E5091-162 3rd /2006 Water 1-131LL pCi/L 84.4 79.9 1.06 E5091-162 3rd /2006 Water 1-131 pCi/L 77.3 79.9 0.97 E5091-162 3rd /2006 Water Ce-141 pCi/L 84.5 88.0 0.96 E5091-162 3rd /2006 Water Cr-51 pCi/L 287 288 1.00 E5091-162 3rd /2006 Water Cs-1 34 pCi/L 85.6 87.0 0.98 E5091-162 3rd /2006 Water Cs-137 pCi/L 174 179 0.97 E5091-162 3rd /2006 Water Co-58 pCi/L 108 112 0.96 E5091-162 3rd /2006 Water Mn-54 pCi/L 116 115 1.01 E5091-162 3rd /2006 Water Fe-59 pCi/L 47.0 44.7 1.05 E5091-162 3rd /2006 Water Zn-65 pCi/L 146 148 0.99 E5091-162 3rd /2006 Water Co-60 pCi/L 130 137 0.95 E5092-162 3rd /2006 Charcoal 1-131 pCi 88.3 91.1 0.97 E5093-162 3rd /2006 Filter Gross Alpha pCi 36.9 37.3 0.99 E5093-162 3rd /2006 Filter Gross Beta pCi 142 147 0.97 E5094-162 3rd /2006 Milk 1-131LL pCi/L 79.9 73.8 1.08 E5094-162 3rd /2006 Milk 1-131 pCi/L 72.5 73.8 0.98 E5094-162 3rd /2006 Milk Ce-141 pCi/L 85.5 86.0 0.99 E5094-162 3rd /2006 Milk Cr-51 pCi/L 288 282 1.02 E5094-162 3rd /2006 Milk Cs-1 34 pCi/L 84.8 85.0 1.00 E5094-162 3rd /2006 Milk Cs-137 pCi/L 171 175 0.98 E5094-162 3rd /2006 Milk Co-58 pCi/L 106 109 0.97 E5094-162 3rd /2006 Milk Mn-54 pCi/L 112 113 0.99 E5094-162 3rd /2006 Milk Fe-59 pCi/L 45.3 43.7 1.04 E5094-162 3rd /2006 Milk Zn-65 pCi/L 146 145 1.01 E5094-162 3rd /2006 Milk Co-60 pCi/L 129 134 0.96 C-6