Saturday, February 4, 2012


 The catastrophic accident at Japan’s Fukushima Daiichi Nuclear Power Plant in March 2011 has resulted in a global re-examination of the safety of nuclear power and teaches us a lot about the risks of continued operation at the Indian Point reactor in New York. Just in the spring and summer of 2011, five nuclear power plants in the United States were damaged and underwent emergency shutdown due to flooding, earthquakes, tornadoes, and hurricanes. A review of the potential radiological consequences of a nuclear accident at Indian Point, the seismic hazards in its location, and cost estimates of a hypothetical accident shows just how dangerous the situation is.
 Among the 104 operating U.S. nuclear reactors, the two units at Indian Point, 34 miles north of Central Park, pose heightened risks. Very large populations could be exposed to radiation in a major accident, the reactors are located in a seismically active area, and their owner currently seeks to extend the reactors’ lives beyond their engineered 40-year lifespan.
1.An accident at Indian Point Unit 3 on the scale of Fukushima Daiichi could require the sheltering or evacuation of as many as 5.6 million people due to a fallout plume blown south to the New York City metropolitan area. People in the path of the plume would be at risk for receiving a whole-body radiation dose greater than 1 rem, which for an average individual results in a 0.3 percent increase in risk of premature death from cancer. An accident of this scale would require the administration of stable iodine to more than six million people (where people would be at risk for receiving a thyroid radiation dose greater than 10 rad).
2. An accident at Indian Point Unit 3 involving a full reactor core melt approaching the scale of Chernobyl could put people in New York City at risk for receiving a wholebody radiation dose greater than 25 rem, resulting in a 7 percent  crease in risk of premature death from cancer for an average individual. An accident of this scale would require the administration of stable iodine throughout the New York City metropolitan area, and put thousands at risk for radiation sickness in and near the Hudson Valley.
3. An accident at one of Indian Point’s reactors on the scale of the recent catastrophe in Japan could cause a swath of land down to the George Washington Bridge to be uninhabitable for generations due to radiation contamination. A release of radiation on the scale of Chernobyl’s would make Manhattan too radioactively contaminated to live in if the city fell within the plume

The Nuclear Regulatory Commission’s (NRC’s) approach to calculating seismic risk used to oversee Indian Point is outdated, and underestimates the danger of a damaging earthquake that could lead to a radiological release. NRDC estimates that, if the plume of radiation headed south from Indian Point to New York City, the cost of a severe accident at the plant would be 10 to 100 times higher than for the Fukushima Daiichi accident, where the cost for cleanup and compensation is projected to exceed $60 billion.
Radiological Releases in a Severe Accident
The Indian Point Energy Center is located in the village of Buchanan, New York, on the east bank of the Hudson River in Westchester County, 34 miles directly north of the center of Manhattan Island.1 Entergy Nuclear Northeast (with headquarters in Jackson, Mississippi), a subsidiary of Entergy Corporation (with headquarters in New Orleans, Louisiana), owns and operates 12 nuclear plants at 10 sites2, including the two operating Pressurized Water Reactor (PWR) units at Indian Point. Figure 1 shows a regional map of Indian Point with 10, 20, and 50 mile rings around the plant drawn. Figure 2 shows an aerial photograph of Indian Point with labels for the containment building3 for Unit 1, which was shut down in October 1974, and containment buildings for Unit 2, which began commercial operation in August 1974, and Unit 3, which began commercial operation two years later.
In Entergy’s 2010 “Indian Point Energy Center Emergency Plan,” the highest category of emergency is termed a “General Emergency” and is described as: “actual or imminent substantial core degradation or melting with potential for loss of containment integrity” with “the potential for a large release of radioactive material.”4 In 1981, Sandia National Laboratory conducted a study for the NRC that predicted a maximum of 50,000 immediate fatalities as far as 17.5 miles downwind and another 14,000 fatal cancers due to radiological releases from a damaged reactor at Indian Point. 5
The 9-11 attacks have caused additional concern that Indian Point could be the target of a terrorist attack. In 2004, a study by the Union of Concerned Scientists estimated as many as 44,000 near-term deaths from acute radiation syndrome and as many as 518,000 long-term cancer deaths could occur in people within 50 miles of Indian Point in the event of a severe accident.6
In order to fully appreciate the implications of a major accident at Indian Point, NRDC used the U.S. Department of Defense (DoD) computer model HPAC (Hazard Prediction and Assessment Capability)7 to calculate resulting fallout plumes. The DoD software contains specific data on the
reactors at Indian Point (as well as at Fukushima Daiichi). Importantly, HPAC computes an inventory of radioactive elements that accumulate in the nuclear fuel rods of these reactors during normal operation. The DoD model captures many other important aspects of the release of radiation due to an accident at a nuclear power plant as well, including the radiological source term, the ambient weather, and data on nearby populations; these terms are defined below.
The source term for an accident at a nuclear plant is the type and quantity of radioactive materials (fission products and transuranic elements) released from the core of a reactor, first into the containment atmosphere and then from within the containment into the surrounding environment. This depends on the design of a reactor, its operating power at the time of the accident, the type of fuel, and the degree of damage to fuel, to containment, and to other reactor components in the accident. The DoD code models three degrees or types of nuclear facility accidents for PWR large
and dry containment leakage and failure. In progressing severity these are: gap release; in-vessel severe core damage; and vessel melt-through.
The PWR accident progression8 begins with loss of reactor coolant and failure of emergency core cooling, as occurred at Fukushima Daiichi due to Station Blackout and earthquake and tsunami damage. As the core heats up, fuel cladding (the metal sheath surrounding the uranium fuel) warps and cracks, resulting in release of the radioactivity located in the gap between nuclear fuel pellets and the cladding: the gap release. If cooling can’t be re-established, the core gradually melts and slumps to the bottom of the reactor pressure vessel (the core’s sealed steel container), called the in-vessel severe core damage. Finally, if the bottom head of the reactor pressure vessel fails, molten core debris can be ejected from the reactor pressure vessel and will react with the concrete floor below: the vessel melt-through.
Preliminary estimates of the amount of radioactive Iodine-131 and Cesium-137 discharged from the Fukushima Daiichi nuclear power plant in the first intense weeks of its 2011 accident are 4.05E+06 Curies (Ci) and 3.24E+05 Ci, respectively. 9 These values are about one-tenth of the quantities of radioactive material released in the 1987 Chernobyl accident in Ukraine.10 Similarly, both the land area highly contamination with Cesium-137 and cancer deaths from radiation exposure are estimated to be on the order of 10 times less for Fukushima Daiichi than for Chernobyl.11
Much of the radiation emitted from Fukushima Daiichi occurred on March 15, 2011, in a plume traveling northwest from the reactors, likely originating from Unit 2. Table 1below shows the DoD HPAC computer model’s source terms for progressively more severe accidents at Fukushima Daiichi Unit 2 and at Indian Point Unit 3. It is important to note that the thermal power of Indian
Point Unit 3 is greater than for Fukushima Daiichi Unit 2, so there is a larger quantity of fuel and radioactive material in the Indian Point reactor. Once the larger power of Indian Point Unit 3 is taken into account, (as shown in Table 1) that the amount of radioactivity calculated by HPAC in the source terms for Fukushima Daiichi and Indian Point are in fact similar. Also note that these calculations were performed  for a hypothetical accident at only one of Indian Point’s two operating reactors, and the accident scenarios did not involve radiation release from the spent fuel pools, unlike for Fukushima, which was a multi-unit accident with damage to spent nuclear fuel storage.
Given estimates of the amount of radiation actually emitted at Fukushima Daiichi, the severity of this accident would fall in between HPAC’s gap release and HPAC’s in vessel severe core damage source terms—a release of about 8percent of the core inventory calculated by the DoD’s HPAC code. The three Indian Point source terms calculated in HPAC bracket the Fukushima Daiichi accident:
1.      Gap release: About two-thirds of Fukushima Daiichi
2.      In-vessel severe core damage: Four to five times higher  than Fukushima Daiichi
3.      Vessel melt-through: nine times higher than  Fukushima Daiichi.
The size of an accident’s source term also depends on the time and duration of a radiation release. For these calculations, it was conservatively assumed that the release of radiation from the Indian Point reactor begins eight hours after an emergency shut-down, or “scram.” It is within this eight-hour period in the hypothetical accident that the reactor core loses cooling; damage to the fuel occurs as it is uncovered and overheats and containment is severely damaged. Importantly, during this eight-hour period between scram and the start of the fallout plume, the intensity of radioactivity in the fuel will decrease as shorter lived radio nuclides produced in the fuel during normal operation of the reactor decay. We conservatively modeled the plume resulting from gap release as emitted over one hour, the plume resulting from in-vessel severe core damage as emitted over two hours, and the plume resulting from vessel melt -through as emitted over ten hours.12
Ambient weather determines in what direction, how far, and how fast radioactive fallout would travel from Indian Point following a major accident. In NRDC’s analysis, we examined wind rose data for the nearby Poughkeepsie/ Dutchess County Airport, shown in Figure 3.13 The length of
the petals in the wind rose shows the frequency with which the wind blows from a given direction averaged over a 10 year period, and the relative size of the colored bands in a petal shows with what probability the wind blows at different speeds. Northerly and westerly winds are predominant at
Indian Point.Winds in the Hudson Valley are most often radiation result in an average radiation exposure of about 0.6 rem. The added risk of exposure to 1 rem to an average individual would increase a person’s chances of getting cancer or dying by about 0.3 percent, 5 rem, by about 1.4 percent, and 25 rem by about 7 percent.
As shown in Table 2, the most extreme accident consequences are for northerly winds carrying the plume to the New York metropolitan area. In the first stage of accident progression, the Gap Release scenario, about three million people would be advised to shelter or evacuate, to reduce the radiation dose and increased risk of cancer and genetic damage. For the next most severe scenario of in-vessel severe core damage, the computer model predicts over five million people could receive the radiation dose allowed for emergency lifesaving workers, which results in elevated 1.4%
increased cancer risk for an average individual. Finally, for a vessel melt-through, the model predicts six million people could receive a radiation dose greater than 25 rem, 10 million people could need stable iodine, and potentially thousands would be at risk for radiation sickness in the areas near to the reactor. Figure 4 through Figure 6 illustrate the fallout plumes from the DoD HPAC calculations for progressively severe accidents at Indian Point occurring at different times
of the day, using historical weather data for the month of October. Figure 7 shows a plume of radiation impacting New York City for the vessel melt-through accident scenario carried by light northerly winds. As can be seen from these figures, the ambient weather plays a large role in the direction and extent, and therefore the consequences, of fallout from an accident.
Seismic Risk
The NRC staff recently recognized that the current state of knowledge related to earthquake threats and accident modeling is not reflected in the regulations at many sites.16 In general, past attempts by the NRC to reconcile disparities between seismic science and nuclear regulations have not been comprehensive, imposing few or no requirements on previously-licensed reactors. In 1996, the NRC set forth two new seismic regulations, but only applied these new criteria to applications submitted after January 10, 1997.   The NRC’s attempts to revise seismic risks at U.S. reactors have suffered from two key flaws: either the scope or methods of the review were limited by scarce data, or the NRC showed deference to voluntary nuclear industry initiatives. When licensees volunteered to reassess earthquake risk, the NRC did not validate the results or even require licensees to report whether or not the studies were  actually completed.17 In a 2008 article by seismologists at Columbia University’s Lamont-Doherty Earth Observatory,18 the authors catalogued 383 earthquakes in the New York region and found concrete evidence for a previously unknown active seismic zone that runs from Stamford, Connecticut, to Peekskill, New York, passing less than a mile north of the Indian Point plant (Figure 8). Due to the zone’s proximity to other known seismic structures, the authors pointed out the possibility of an earthquake of magnitude 6 or higher along the zone.
The authors go as far as to say that the Indian Point site in particular “is clearly one of the least favorable sites in our area study from an earthquake hazard and risk perspective.” This study illustrates that new forms of sophisticated analysis, decades of new data on tremors, and improved
models together provide valuable insight into the extent to which current NRC regulations may be lacking. In April 2011, the NRC conducted an inspection at Indian Point Nuclear Generating Unit 2 and reported that the “licensee identified a number of potential vulnerabilities regarding firefighting following a Safe Shutdown Earthquake  (SSE). The potential vulnerabilities stem from the fact that
the fire protection system in non-safety related buildings, buried/underground fire headers, fire pumps, and the city water makeup supply are not seismically designed which could result in a loss of portions of the fire protection system following a SSE.”19 A SSE is the maximum earthquake
potential for which certain structures, systems and components important to safety are designed to remain functional.
Currently, the NRC is conducting a process begun in 2005 to evaluate seismic hazards based on new data for the Central and Eastern United States; this process is called GI-199. A determination of the site-specific seismic hazards and associated plant risk are planned for the next phase of GI-199. However, the overall process appears to be falling short of implementing the already-known seismic criteria established in 1996.On the surface, the results of GI-199 only seem to establish how these new seismic evaluations are considered through a cost-benefit analysis. But if the finding within GI-199 emerges that Indian Point is indeed lacking in its ability protect against earthquakes (an August 2010 NRC report revealed that Indian Point Unit 3 had the highest probability of core damage of any plant in the country)20then the implications are compounded by the power plant’s
proximity to large populations.
Fukushima and the Potential Economic Costs of an Accident at Indian Point
The cost of the nuclear accident at Fukushima Daiichi is enormous. In August of 2011 Tokyo Electric Power Company (TEPCO), the utility which owns the Fukushima Daiichi reactors and other plants impacted by the Great East Japan Earthquake and tsunami, posted a $7.39 billion loss for its April to June quarter.21 This loss includes a projection of costs through the final phase of TEPCO’s roadmap to achieve cold shutdown of the Fukushima reactors between October 2011 and January 2012. TEPCO's estimated losses, detailed in the assessment, included:
1.      $680 million operating loss due to suspended operations at nuclear plants and replacement with thermal generating capacity
2.      $1.37 billion cost for resources to bring the crisis at the plant under control
3.      $1.15 billion compensation for mental distress caused by the accident
4.      $1.32 billion compensation to companies that became inoperable due to the evacuation orders and other reasons
5.      $1.84 billion compensation to people who could not work because of the accident
6.      $870 million compensation for losses caused by shipment restrictions on agriculture and marine products due to radiation contamination. On September 9, 2011, the Japanese government announced that it planned to spend $2.9 billion on cleaning up residential areas contaminated by the Fukushima accident.  Japan’s Chief Cabinet Secretary Osamu Fujimura described the government’s plan to build a facility to store radioactive material in Fukushima Prefecture before it is removed to a final disposal site.22 These costs are in addition to multibillion capital losses from destruction of the reactors themselves and loss of the value of their future generating capacity. And more recently, a Japanese government panel reviewing TEPCO’s finances projected that the utility company would eventually face damages of at least $59 billion.23 Real estate and economic activity within the New York area is among the most valuable in the world. The damage claims from radioactive contamination of this region would be vast. In the 2004 Union of Concerned Scientists’ study, theeconomic damages within 100 miles of Indian Point were calculated to exceed $1.1 trillion for the worst cases evaluated, using NRC methodologies. Estimating the full cost of a severe accident at Indian Point is difficult, but it can be inferred from two factors that the cost of an accident at the power plant would indeed be one to two orders of magnitude higher than the eventual total cost of the Fukushima Daiichi accident.
First, it is likely that winds blew some of the fallout from Fukushima Daiichi eastward out to sea, reducing the radiation dose to nearby populations and diminishing contamination of land. Second, the Fukushima Daiichi accident was located in a predominantly non-urban area. Neither of these
considerations would hold for Indian Point.  One factor affecting the cost of an accident at Indian
Point would be the extent of the ground concentration of radioactive materials downwind from the reactor. Following the Chernobyl accident, cesium-137, a radionuclide with a half-life of about 30 years, contaminated over 1,000 square kilometers to a level greater than 40 Curies per square  kilometer, a level of contamination at which the population was encouraged to leave permanently. The accident at Fukushima Daiichi produced a zone of similar levels of contamination of cesium-137 to the northwest of the plant over about 175 square kilometers. NRDC’s calculations for a Fukushima-scale accident and for a Chernobyl-scale accident at Indian Point, on a day with typical, northerly winds, are shown in Figure 9. As can be seen from this figure, an accident at one of Indian Point’s reactors on the scale of Chernobyl’s would make Manhattan too radioactively contaminated to live in if the city fell within the plume.

1 The Indian Point site measures 239 acres and is centered at 41° 16’ 11” latitude, 73° 57’ 8” longitude (41.269722 N, 73.952222 W).
2 In addition to the two units at Indian Point, Entergy Nuclear owns and operates: Arkansas Nuclear
(Units 1 and 2) near Russellville, Arkansas; Cooper Nuclear Station near Brownville, Nebraska;
FitzPatrick in Oswego, New York; Grand Gulf Nuclear Station near Port Gibson, Mississippi; Pilgrim Nuclear Power Station in Plymouth, Massachusetts; Palisades Power Plant in Covert, Michigan; River Bend Station near St. Francisville, Louisiana; Vermont Yankee in Vernon, Vermont; and Waterford 3 in Taft, Louisiana.
3 Of the three types of containment structures for PWRs – Large Dry, Subatmospheric, and Ice
Condenser – Indian Point Unit 2 and Unit 3 have steel-lined reinforced concrete Large Dry containment structures with hemispherical domes and flat bases.
4 Frank Phillips and Brian Sullivan “Indian Point Energy Center Emergency Plan,” (Revision 10, Entergy Corporation, December 2010), pp. D-5, D-17.
5 Subcommittee on Oversight & Investigations, Committee on Interior and Insular Affairs, U.S. House of Representatives, “Calculation of Reactor Accident Consequences (CRAC2) For U.S. Nuclear Power Plants Conditional on an ‘SST1’ Release,” November 1, 1982. In July, 2011 the Union of Concerned Scientists analyzed documents it obtained under the Freedom of Information Act from the NRC, and found that an updated analysis of severe nuclear accidents – NRC’s State of the Art Reactor Consequence Analysis or SOARCA – did not differ substantially from the 1982 study.
6 Edwin S. Lyman, Chernobyl on the Hudson? The Health and Economic Impacts of a Terrorist Attack at the Indian Point Nuclear Plant, (Washington, D.C.: Union of Concerned Scientists, Commissioned by Riverkeeper, September 2004) p. 4.
7 Hazard Prediction and Assessment Capability, version 4.0.4 ( Washington, D.C.: Defense Threat Reduction Agency , April 2004). The HPAC documentation describes the code as: “…a counter proliferation, counterforce tool that predicts the effects of hazardous material releases into the atmosphere and its collateral effects on civilian and military populations. HPAC assists warfighters
in destroying targets containing weapons of mass destruction (WMD) and responding to hazardous
agent releases. It employs integrated source terms, high-resolution weather forecasts and particulate transport algorithms to rapidly model hazard areas and human collateral effects.”
8 L Soffer, S. B. Burson, C. M. Ferrell, R. Y. Lee, J. N. Ridgely, “Accident Source Terms for  ight-Water Nuclear Power Plants: Final Report (NUREG-1465),” (Washington, D.C.: Office of Nuclear Regulatory Research, U.S. Nuclear Regulatory Commission, February 1995), pp. 2-3.
9 Masamichi Chino, Hiromasa Nakayama, Haruyasu Nagai, Hiroaki Terada, Genki Katata And  Hiromi Yamazawa, “Preliminary Estimation of Release Amounts of 131I and 137Cs Accidentally Dischargedfrom the Fukushima Daiichi Nuclear Power Plant into the Atmosphere,” Journal of Nuclear ScienceAnd Technology, 48, no. 7, p. 1129–1134, 2011.
10 L. Devell, S. Guntay, and D. A. Powers, “The Chernobyl Reactor Accident Source Term: Development of a Consensus View,” (Issy-les-Moulineaux, France: Committee on the Safety of Nuclear Installations, OECD Nuclear Energy Agency, November 1995).
11 Frank N. von Hippel, “The radiological and psychological consequences of the Fukushima Daiichi accident,” Bulletin of the Atomic Scientists 67, no.5, pp 27-36.
12 NUREG-1465, pg. 9.
13 Ricardo K. Sakai, David R. Fitzjarrald, Chris Walcek, Matt J. Czikowsky, and Jeffrey M. Freedman, ”Wind Channeling in the Hudson Valley, NY,” (2006), p. 1.
14 Manual of Protective Action Guides and Protective Actions for Nuclear Incidents, (Washington, D.C.:Office of Radiation Programs, United States Environmental Protection Agency).
15 Manual of Protective Action Guides and Protective Actions for Nuclear Incidents, pg. 2-12.
16 Recommendations for Enhancing Reactor Safety in the 21st Century – The Near-Term Task ForceReview of Insights from the Fukushima Daiichi Accident, (Washington, D.C.: Nuclear RegulatoryCommission, July 12, 2011), pp. 25-30.
17 Supplement 4 to GL 88-20, “Individual Plant Examination of External Events (IPEEE) for Severe Accident Vulnerabilities, 10 CFR 50.54(f)” Nuclear Regulatory Commission, August 29, 1989.
18 LR Sykes, JG Armbruster, W Kim, L Seeber, “Observations and Tectonic Setting of Historic and Instrumentally Located Earthquakes in the Greater New York City-Philadelphia Area,” Bulletin of the Seismological Society of America 98, no.4 (August 2008), pp. 1696-1719.
19 Indian Point Nuclear Generating Unit 2 - NRC Temporary Instruction 2515/183 Inspection Report 05000247 1201 1009, Lawrence T. Doerflein, Chief Engineering Branch 2, Division of Reactor Safety, Nuclear Regulatory Commission, May 13, 2011.
20 “Generic Issue 199 (GI-199), Implications of Updated Probabilistic Seismic Hazard Estimates in Central and Eastern United States on Existing Plants, Safety/Risk Assessment,” August 2010.
21 Kazumasa Takenaka, “TEPCO Posts 571 Billion Yen Net Loss in Quarter,” The Asahi Shimbun, August 10, 2011
22 “Decon Plan May Cost ¥220 Billion,” The Japan Times, Saturday, September 10, 2011.
23 Tsuyoshi Inajima and Yuji Okada, “Tepco Faces ‘Zombie’ Future as Fukushima Claims Set to Surpass  $59 Billion,” Bloomberg, September 30, 2011.
24 Jase Bernhardt, Victoria Kelly, Allison Chatrchyan, and Art DeGaetano, The Natural Resource
Inventory of Dutchess County NY: Chapter 2 Climate and Air Quality, Revised October 2010, pp. 13-14.

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