ML13165A242

Summary of Public Meeting Webinar to Discuss Nrc'S Perspectives on Palisades Nuclear Power Plant Effluents

ML13165A242
Person / Time
Site:	Palisades
Issue date:	06/13/2013
From:	Jack Giessner Reactor Projects Region 3 Branch 4
To:
References
Download: ML13165A242 (13)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION REGION III 2443 WARRENVILLE ROAD, SUITE 210 LISLE, IL 60532-4352 June 13, 2013 LICENSEE: Entergy Nuclear Operations, Inc.

FACILITY: Palisades Nuclear Plant

SUMMARY

OF THE MAY 23, 2013, PUBLIC MEETING WEBINAR REGARDING NUCLEAR POWER PLANT EFFLUENTS On May 23, 2013, the U S. Nuclear Regulatory Commission (NRC) held a two part Public Meeting webinar to discuss NRCs perspectives on nuclear power plant effluents. During the first part of the meeting, the NRC staff presented an overall discussion regarding the basics of power plant effluents, and the regulatory requirements that apply to releases from plants. is a list of attendees at the meeting. Copies of the slides used by the NRC staff during the meeting can be accessed through the NRCs Agency wide Document Access and Management System: ADAMS (ML13140A358).

The NRC staff stated in the opening remarks that the second part of the meeting was geared towards answering follow up questions from the public about nuclear plant releases and the recent leak at Palisades. There were 74 meeting participants that had the opportunity to submit questions to the NRC staff about effluent issues through the Webinar process.

In addition to answering questions from members of the public on May 23, NRC representatives agreed to provide an answer to technical questions regarding the topic of effluents that were submitted during the meeting, but were not answered during the allocated meeting time. The answers to these questions and the follow-up to two questions answered during the webinar are included in this meeting summary (Enclosure 2). A recording of the webinar can be accessed through ADAMS (ML13162A570). Additionally, a recording of the previous webinar related to Pressurized Thermal Shock (ML13108A336) can be found on ADAMS (ML13162A550).

Entergy Nuclear Operations, Inc. Please note that these recordings will take additional time to download because of the large file size. The recordings can be accessed on the second page of the PDF document by clicking on the forward arrow located on the bottom left corner.

Sincerely,

/RA/

John B. Giessner, Chief Branch 4 Division of Reactor Projects Docket Nos. 50-255 and 72-007 License No. DPR-20

Enclosures:

As Stated cc w/encls: Distribution via ListServTM

PUBLIC MEETING PRINCIPAL ATTENDEES May 23, 2013 NRC Attendees C. Casto, Regional Administrator, RIII C. Pederson, Deputy Regional Administrator, RIII J. Giessner, Chief, Division of Reactor Projects, Branch 4 J. Cassidy, Senior Health Physicist, Division of Reactor Safety, RIII M. Phalen, Senior Health Physicist, Division of Reactor Safety, RIII R. Conatser, Health Physicist, Office of Nuclear Regulatory Research S. Shah, Reactor Engineer, Division of Reactor Projects, Branch 4 V. Mitlyng, Senior Public Affairs Officer, RIII P. Chandrathil, Public Affairs Officer, RIII Enclosure 1

Questions for the NRC Meeting on May 23, 2013

1. What is aluminum - concrete interaction?

The aluminum concrete interaction is an interaction which causes corrosion of the aluminum. Unlike steel which corrodes rapidly in acidic solutions, aluminum corrodes in both acidic and basic environments. Wet concrete is a very basic environment.

Recently, in some locations where the aluminum bottom or nozzles of the safety injection refueling water tank were in contact with the tanks concrete base, a small amount of corrosion has been observed. The appearance and amount of corrosion observed are about what should be expected for aluminum in contact with wet concrete.

No other type of corrosion appears to be involved.

2. Why did the NRC think that 38 gallons per day of radioactive water leakage into the control room at Palisades was acceptable? What if the water had reached safety-critical electric circuits or equipment? Couldnt control on the reactor have been lost, with the loss of equipment? Why didnt NRC tell the public about the leak into the control room?

It took courageous Palisades whistleblowers, their attorney, and a Member of the U.S. Congress to bring the leakage into the control room to public knowledge.

The 38 gallons per day (gpd) value is leakage that would be allowed from the tank. This leakage should not go to the control room. During the most recent leak from the safety injection refueling water tank (SIRWT), no leakage occurred into the control room. On a couple distinct occasions leakage did go into the control room. Leakage into the Palisades control room occurred on the following occasions at very low quantities and short periods of time: several days in May 2011 (less than 0.08 gpd), May 2012 (very small quantity on the order of a couple ounces), June 29, 2012 (very small quantity on the order of a couple ounces) and several hours on June 3, 2013 (maximum of a couple ounces). At no point did this leakage reach the 38 gpd rate. In all cases, the NRC resident inspectors verified that there was no impact on equipment as a result of this leakage. If this leakage reached safety-related circuits, it is unlikely that there would be a loss of reactor control with such low quantities of water dripping (a few drops per minute). In addition, safety-related components required to shut down the reactor are required to be designed with at least two redundant and independent components with separate electrical circuits. This design will ensure that failure of one circuit/component will not affect the other. The public was not notified of this leak because the leak was minor and did not impact any safety-related equipment. The NRC notes that this leakage should not have occurred and is taking action to ensure the licensee addresses the issue.

3. Why was the SIRW tank allowed to be built right above the control room? Wasnt this asking for trouble over 40 years ago? Why was this allowed?

The licensee submitted their original application in accordance with NRC construction requirements. The SIRWT was constructed in accordance with these requirements.

The design met all NRC requirements and regulations. These requirements provide assurance of tank safety. The licensees application included technical information regarding the SIRWTs structure and components; its material composition; the environment that it is exposed to; and the applicable effects for each material and 1 Enclosure 2

environment combination. Therefore, the original design to establish the SIRWT above the auxiliary building was acceptable. If the NRC discovers information which shows the construction did not meet appropriate requirements, or discovers new information which affects the safety of the tank, the NRC would take appropriate action to ensure plant safety.

4. Isnt it true that there are no real time radioactivity monitors installed directly on the dry casks storing high-level radioactive waste? Why not?

There are no real time radioactivity monitors installed directly, and none are required, on the dry fuel storage casks because NRC regulations require spent fuel storage systems to be designed to remain subcritical under all credible normal, off-normal and accident conditions. Regulations specific to nuclear criticality safety of the cask system are specified in Part 10 Code of Federal Regulations (CFR) 72.124:

(http://www.nrc.gov/reading-rm/doc-collections/cfr/part072/part072-0124.html) and 72.236(c) (http://www.nrc.gov/reading-rm/doc-collections/cfr/part072/part072-0236.html).

Other pertinent regulations include 10 CFR 72.24(c)(3), 72.24(d):

(http://www.nrc.gov/reading-rm/doc-collections/cfr/part072/part072-0024.html) and 72.236(g) (http://www.nrc.gov/reading-rm/doc-collections/cfr/part072/part072-0236.html).

Moreover, the safety of the cask design is required to be established on the basis of an acceptable geometry or permanent poisons that absorb neutrons. When solid neutron absorbing materials are used, the design is required to provide for a positive means to verify their continued efficacy during the storage period. Per NRC regulations, criticality safety of the cask system does not rely on the use of burn-up of the fuel and fuel-related burnable neutron absorbers.

Periodic monitoring of the casks is performed to ensure there is no loss of shielding.

Both the vertical and horizontal casks are subject to the dose limit requirements specified in 10 CFR Part 20 and 72. Specifically, the regulatory requirements for radiation protection are specified in Part 72.104 and Part 20.1301:

§ 72.104 Criteria for radioactive materials in effluents and direct radiation from an Independent Spent Fuel Storage Installation (ISFSI) or Vertical Storage Casks (VSC):

(a) During normal operations and anticipated occurrences, the annual dose equivalent to any real individual who is located beyond the controlled area must not exceed 0.25 mSv (.025 rem to the whole body, 0.75 mSv (.075 rem) to the thyroid and 0.25 mSv (.025 rem) to any other critical organ as a result of exposure to:

§ 20.1301 Dose limits for individual members of the public:

(a) Each licensee shall conduct operations so that (1) The total effective dose equivalent to individual members of the public from the licensed operation does not exceed 1 mSv (.1 rem) in a year.

To comply with these requirements, licensees place dosimeters around the ISFSI perimeter and monitor them periodically. Typically the dosimeters are read on a quarterly basis. This program is controlled by the radiation protection program at the site and is part of the NRCs inspection. Additionally, surveys are performed at some frequency on the ISFSI pad, typically performed on a monthly or quarterly basis. Any degradation in shielding would likely be detected in one of these surveys. When NRC 2 Enclosure 2

inspectors conduct inspections related to ISFSI, we perform our own independent surveys of the casks.

For example, this is the license requirement for the ventilated (vertical) storage casks (VSC-24s):

2.3.2 CofC § 1.3.2, "Exterior Ventilated Concrete Cask (VCC) Surface Inspection" Surveillance: The VCC exterior surface shall be inspected annually for any damage (chipping, spalling, etc.).

The design function of the VCC is to provide shielding and protect the canister containing fuel. Any external degradation would be evaluated against the required design requirements.

5. How far away do the sediment tests take place along the water? I live within half mile south of the plant. The water released into the lake may travel away from the plant and end up near me. Are the tests only on the plant lake shore property?

One sample is collected semiannually from the beach between the north boundary of the plant and the Van Buren State Park, approximately 1/2 mile north of the plant discharge.

These samples taken near the plant conservatively capture the highest amount of activity from plant releases and ensure that this activity is below the established NRC limits for public safety. Activity from these releases is also reduced as a result of dilution as the water travels away from the plant. Therefore, the activity from plant releases in regions far away from the plant is well below any NRC or EPA limits.

6. Isnt it true that the SIRW tank water also does contain radioactive hot particles that can emit doses measured in rems per hour, if not tens of rems per hour? This too could have leaked out into the Lake, right? What if someone drinks that? Isnt that a health risk?

There is no associated health risk from previous releases related to the SIRWT. It is true that radioactive hot particles have been previously identified inside the SIRWT after the water was drained, although not at the dose rates implied in the question. No radioactive hot particles were identified outside of the tank. As the name indicates, radioactive hot particles are particles, like a grain of sand, that have size and mass. It would not be expected that a particle could pass through the dimensions of the crack identified in the SIRWT. Even if the radioactive hot particle COULD pass through the crack, the mass and the pathway would prevent the particle from reaching Lake Michigan or a member of the public. As a result, hot particles, like what are described in the question, have no chance of being in the drinking water.

7. Isnt it true that there is no economically feasible way to filter tritium out of water, steam or air? Isnt it true that NRC simply allows tritium to be discharged into the environment? So long as the concentration of tritium in water or air is below a certain level. Couldnt Entergy then just use more water, or more air, to dilute the tritium to an allowable concentration? That is, whats stopping Palisades from just releasing all its tritium into the environment?

3 Enclosure 2

There are two NRC requirements and both must be met for plant releases to the environment; release rate and total dose. The two parameters assess different functions of the release. Release rate assesses the control of the release, while total dose assesses the impact on the general public. Release rate, as the name implies, is a function of time or concentration; parameters that can be controlled by reducing the concentration by extending the release duration, or reducing the concentration through dilution. Total dose is determined for the total activity of the release and is not affected by the release duration or dilution. The dose from all releases from the nuclear power plants is well below the values established by the Environmental Protection Agency (EPA) and these levels ensure the general public is protected from the adverse health effects of ionizing radiation. Palisades tritium releases have been maintained below NRC allowable concentrations. Drinking water at the South Haven water supply and the Palisades Park, south of the plant, show no detectable activity of tritium. The NRC would take required actions per its regulations if tritium release concentrations exceeded the allowable limits.

8. What about seasonal batch releases of radioactive liquid discharge into Lake Michigan?

Why doesnt NRC have safety and health protection regulations prohibiting Palisades from doing this on a summer Saturday, when there could be hundreds of people swimming and boating and fishing immediately downstream of Palisades discharge pathway. Shouldnt Palisades be required to warn the public to stay out of the Lake when it is doing these seasonal batch releases into the Lake?

The regulations for protecting the public are effective every day of year. One of these regulations requires the licensee to calculate the resultant dose commitment for the release which is then added to all other releases for the calendar year, not just any given day. The dose from all releases from the plant is well below the values established by the EPA and these levels ensure the general public is protected from the adverse health effects of ionizing radiation. Therefore, warnings are not warranted. The NRC will take required actions per its regulations if release concentrations into the Lake exceed the allowable limits.

9. Jack Giessner just said no detectable tritium in Lake Michigan. But even natural levels are 3 to 24 pico-curies per liter in the earths surface water. Artificial tritium would add to that. Shouldnt NRC have better detectors? Obviously, there is both natural, and more significantly, artificial tritium, in Lake Michigans water. Shouldnt NRC be able to detect it?

It is true that tritium is produced naturally through cosmic radiation and there are detectable levels of tritium in the earths surface water. Tritium was also created as a result of nuclear weapons testing fallout in the 1950s and 1960s. This tritium has been decaying since that time. The NRC established detection capabilities for environmental sample analysis sufficiently low to detect levels that ensure the general public is protected from the adverse health effects of ionizing radiation. The detection capabilities are adequate and have previously detected tritium that is the result of this fallout.

4 Enclosure 2

10. Is NRC doing its own environmental monitoring for Palisades radiological releases?

Or does NRC depend entirely on Entergys own testing? How can Entergy be trusted?

Isnt this a violation of chain of custody of samples? It puts a lot of trust in Entergy, doesnt it, this approach?

Per Title 10 Code of Federal Regulations (CFR) 50.9, Completeness and Accuracy of Information, licensees are required to provide complete and accurate information to the NRC. Licensees who willfully present misleading information to the NRC would be in violation of 10 CFR 50.5, Deliberate Misconduct, and are subject to NRC enforcement per the NRC Enforcement Policy located at http://www.nrc.gov/about-nrc/regulatory/enforcement/enforce-pol.html. Although the NRC does not perform environmental monitoring near the Palisades plant or other nuclear power plants, it ensures, through its inspections, that the licensee is performing required environmental monitoring and providing this information to the NRC. The NRC measures nuclear plant performance through a combination of objective performance indicators reported by the licensee and through NRC inspection findings. They are both closely focused on those plant activities having the greatest impact on public safety and overall risk.

11. Can a licensee change calculational parameter values, such as the assumed dilution factor, without NRC approval?

The NRC is required to be informed of all changes to the Offsite Dose Calculation Manual (ODCM). However, a licensee can make some changes to the ODCM via an NRC approved process without prior NRC approval or license amendment. These changes are limited changes that do not impact a licensees ability to maintain the level of radioactive effluent control required by NRC and EPA regulations, and do not adversely impact the accuracy or reliability of effluent, dose, or set point calculations. In addition, for accidents, which are evaluated in the safety analysis report of the plant, the licensee can make changes as long as it does not result in more than a minimal increase in the radiological consequences of an accident in that analysis. The licensee must make changes to the ODCM in accordance with the licensees Technical Specifications.

All changes have to be documented with a justification to demonstrate the effectiveness of the radioactive effluent control program has not been reduced. ODCM changes have to be reviewed by a qualified reviewer (typically the licensees Plant Operations Safety Review Committee) and the changes become effective after approval by the licensees Plant Manager (per Technical Specifications/ODCM). As stated earlier, all changes to the ODCM must be submitted to the Commission as part of the Annual Radioactive Effluent Release Report as required by the licensees Technical Specifications and ODCM with changes identified by markings in the margin of the affected pages, clearly indicating the area of the page that was changed, and shall indicate the date (e.g.,

month/year) the change was implemented. The NRC makes these changes available on the public webpage and in ADAMS. The NRC inspector reviews changes to the ODCM during the routine baseline inspections. The NRC has the right to challenge any changes to the ODCM. On occasion, the NRC has issued inspection findings to licensees for not following the process, or for making changes that were not appropriate.

5 Enclosure 2

12. You just said the risk from the 82.1 gallon leak of radioactivity into Lake Michigan was small. You compared the radioactive leak into the Lake to living in a brick house, or flying at high altitude. But tritium in the leak, if ingested by a South Haven resident from their tap water, could organically bind, in any and all of their cells, tissues, and organs.

Organically bound tritium can do damage for a decade in a human body. Radiation exposure from brick and high altitude flight is from gamma rays, an external dose, for a short period. Ingested radioactive contaminants are internal doses, which can be chronic for years. Why didnt your speaker talk about the difference between internal and external exposures?

In the webinar, the NRC staff gave examples of internal dose and external dose. In the presentation, the NRC staff compared the risk from the tank leak to the risks associated with 3 everyday situations. The following situations were mentioned in the presentation.

• Living in a brick or stone house for 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br />

• Living with the radioactivity in a human body for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />

• One minute of flying at high altitude on a cross-country flight The first and third examples are the external dose scenarios you mentioned. The second example, exposure to radioactivity in the human body, involves internal dose.

A person receives about .014 rem (14 mrem) per year from the natural potassium they ingest from various foods. The NRC staff did not go into any detail about the internal dose during the webinar; however, here is some relevant information:

More detail is provided below on internal exposure from naturally occurring radioactivity consumed, such as that from potassium. The US Food and Drug Administration (FDA) established a minimum daily allowance (MDA) for potassium. There is an amount of natural potassium the human body needs to maintain the proper amount of electrolytes in the body. If the concentration of electrolytes (potassium) in the human body is too low, it can be fatal. In general, we ingest very low levels of radioactive materials, such as potassium, every day. So all of us have low-level, long-term exposure to natural radioactive materials, and that exposure occurs throughout our lifetime. So even though no health effects are expected from the tank leak at Palisades, an estimate of the health risk from that leak can be calculated. The estimated risk associated with the tank leak is similar to the risk posed by the internal dose a person receives in one hour from the natural potassium in their own body - a very small amount.

Regarding the radioactivity of drinking water: Palisades Park was sampled after the leak and has shown no detectable tritium. The South Haven water supply is scheduled to be tested, but those tests have not been completed. Based on current information, tritium from the tank leak at Palisades is not expected to impact the South Haven water supply.

13. Radon is deemed the second leading cause of lung cancer. Why even use natural radiation as a metric. Arsenic can also be natural. No one recommends ingesting it.

6 Enclosure 2

In order to get a perspective on the health consequences of the tank leak at Palisades, it is helpful to compare it to other sources of radiation exposure. The intent of the webinar was to compare impacts to a person. Radon occurs naturally in the environment and radon is a major source of natural radiation for the typical person in the United States.

Because radon occurs naturally, some exposure to radon is unavoidable. To ensure public safety, the EPA established regulations and standards to limit radon so that the health and safety of the public are protected. If radon is controlled to sufficiently low concentrations, the radiation exposure is reduced to a level that the EPA establishes as acceptable. The radiation dose from the tank leak at Palisades is much less than the dose the average person receives from typical radon levels that are considered acceptable.

14. Jack Giessner just said that there is no evidence that a 10 rem dose shown any evidence of health risks. But the International Council on Radiation Protection figures show that a 10 rem per year exposure rate would result in very high cancer incidence rates - 1 in 4 people exposed to such levels for a lifetime (70 years) would develop cancer because of such high levels of exposure. And about half of those cancer cases will end in death from that cancer. So a 0.1 rem per year exposure, which NRC allows as acceptably risky, would allow for a 1% cancer incidence rate compared to that 10 rem per year exposure. So, 0.1 rem per year could cause a 1 in 400 cancer incidence rate, right? And about a 1 in 800 cancer fatality rate, right? Is my math correct?

Suggestions that very low doses of radiation are known to cause cancer are not supported by the technical literature. The most recent information from the International Commission on Radiological Protection (ICRP), ICRP Report 103, states, There is general agreement that epidemiological methods used for the estimation of cancer risk do not have the power to directly reveal cancer risks in the dose range up to around 100 mSv (which is 10 rem).

The ICRP (in ICRP-103) also states, the [ICRP] judges that it is not appropriate, for the purposes of public health planning, to calculate the hypothetical number of cases of cancer or heritable disease that might be associated with very small radiation doses received by large numbers of people over very long periods of time.

The dose from the Palisades tank leak was calculated to be 0.000002 rem. This is commonly accepted to be a very low dose. The scientific literature indicates no health effects would be expected for such a low dose of radiation. Please see response to question 17.

15. On your radiation protection exposure pie chart, you said that National Council on Radiation Protection (NCRP) was the source of the information. NCRP is now proposing a 1 in 6 cancer rate, due to exposure to radioactive exposure due to contamination after a radiological event. How much faith and trust can we put in an institution willing to let the American people live amidst radioactive contamination, and die at a rate equivalent to a game of Russian roulette that ends badly?

Most, if not all, of the information on the NCRPs pie chart is available from other sources. The NCRP is not responsible for establishing the federal standards and limits for radiological emergencies. The EPA is the agency in the United States that 7 Enclosure 2

establishes the standards for radiological events that impact the general environment.

Additionally, the NRC is the agency that regulates radioactive effluents from commercial nuclear power plants. The EPA and the NRC establish the radiological standards and limits used in the United States to protect the health and safety of the public.

16. Lake Huron has an average tritium level of 5bq/l. What is the level in Lake Michigan?

Prior to significant nuclear weapon testing in the early 1950s, tritium levels in Lake Michigan were about 6 pCi/L. In the mid-1960s, Lake Michigan had a tritium concentration of about 19 Bq/L (which is 513 pCi/L) due to the weapons testing being conducted at the time. Based on the most recent data available, Lake Michigans tritium concentration has been decreasing since about 1963. That inventory of tritium has been decaying, and the concentration in 1997 and 1998 was 3 Bq/L (or 81 pCi/L). The level is likely lower today. From Tritium in the Canadian Environment: Levels and Health Effects, Canadian Nuclear Safety Commission, March, 2002.

http://www.odwac.gov.on.ca/standards_review/tritium/Osborne_CNSC-RSP-0153-1.pdf.

http://deepblue.lib.umich.edu/bitstream/handle/2027.42/93604/mmpp013.pdf?sequence

=1.

17. Why did you not mention that the linear no-threshold (LNT) has not been demonstrated below 5 rem acute doses and therefore, application at low levels is a mathematical method for estimating risk on the assumption that LNT is applicable?

Studies indicate that doses above about 10 rem may reasonably be associated with some health effects. As the dose above 10 rem becomes greater, the health effects become greater. This is not the case below 10 rem. During the webinar, the NRC staff mentioned that scientific studies indicate there is no observable evidence of adverse health effects for doses below about 10 rem (See question #14 above). At low doses, where no health effects have been observed either in reality or during scientific studies, a mathematical model (LNT) is used to estimate risks. The NRC recognizes this, and for purposes of establishing limits, design objectives, and reporting levels, the NRC assumes a linear relationship (between risk and dose) exists below 10 rem. The NRC establishes regulations at values below 10 rem to ensure the regulatory limits are protective of the health and safety of the public. The occupational dose limit for workers is 5 rem in a year and the dose limit for the public is 0.1 rem per year.

8 Enclosure 2

Entergy Nuclear Operations, Inc. Please note that these recordings will take additional time to download because of the large file size. The recordings can be accessed on the second page of the PDF document by clicking on the forward arrow located on the bottom left corner.

Sincerely,

/RA/

John B. Giessner, Chief Branch 4 Division of Reactor Projects Docket Nos. 50-255 and 72-007 License No. DPR-20

Enclosures:

As Stated cc w/encls: Distribution via ListServTM DOCUMENT NAME: Palisades Meeting Summary May 23, 2013 Publicly Available Non-Publicly Available Sensitive Non-Sensitive To receive a copy of this document, indicate in the concurrence box "C" = Copy without attach/encl "E" = Copy with attach/encl "N" = No copy OFFICE RIII RIII NAME SShah:rj JGiessner DATE 06/13/13 06/13/13 OFFICIAL RECORD COPY

Letter to Entergy Nuclear Operations, Inc. from J. Giessner dated June 13, 2013

SUMMARY

OF THE MAY 23, 2013, PUBLIC MEETING WEBINAR REGARDING NUCLEAR POWER PLANT EFFLUENTS DISTRIBUTION:

Doug Huyck RidsNrrPMPalisades Resource RidsNrrDorlLpl3-1 Resource RidsNrrDirsIrib Resource Chuck Casto Cynthia Pederson Steven Orth Allan Barker Carole Ariano Linda Linn DRPIII DRSIII Patricia Buckley Tammy Tomczak ROPassessment.Resource@nrc.gov