Nuclear Street - Nuclear Power Portal

Order to Modify Licenses with Regard to Reliable Hardened Containment Vents

Nuclear Street News — Wed, 14 Mar 2012 14:26:35 GMT

The attached Order applies only to U.S. boiling-water reactors that have “Mark I” or “Mark II” containment structures.

The NRC has determined that ensuring adequate protection of public health and safety requires that all operating BWR facilities with these containments have a reliable hardened venting capability for events that can lead to core damage. These new requirements provide greater mitigation capability consistent with the overall defense-in-depth philosophy, and therefore greater assurance that the challenges posed by severe external events to power reactors do not pose an undue risk to public health and safety.

The Order has been issued to the following plants: Limerick, Nine Mile Point, Pilgrim, Perry, Susquehanna, River Bend, Clinton, Vermont Yankee, Fitzpatrick, Columbia, Quad Cities, La Salle, Duane Arnold, Monticello, Grand Gulf, Cooper, Fermi, Dresden, Browns Ferry, Brunswick, Hatch.

Order to Modify Licenses with Regard to Reliable Spent Fuel Pool Instrumentation

Nuclear Street News — Wed, 14 Mar 2012 14:08:22 GMT

The attached Order requires the plants to install enhanced equipment for monitoring water levels in each plant’s spent fuel pool.

The spent fuel pool level instrumentation at U.S. nuclear power plants is typically narrow range and, therefore, only capable of monitoring normal and slightly off-normal conditions. Although the likelihood of a catastrophic event affecting nuclear power plants and the associated spent fuel pools in the United States remains very low, beyond-design-basis external events could challenge the ability of existing instrumentation to provide emergency responders with reliable information on the condition of spent fuel pools. Reliable and available indication is essential to ensure plant personnel can effectively prioritize emergency actions.

The NRC has determined that the spent fuel pool instrumentation required by this Order represents a significant enhancement to the protection of public health and safety and is an appropriate response to the insights from the Fukushima Dai-ichi accident

The Order has been issued to the following plants: Susquehanna, La Salle, Perry, Limerick, Vermont Yankee, Oyster Creek, Hatch, Monticello, River Bend, Quad Cities, Peach Bottom, Hope Creek, Cooper, Fitzpatrick, Columbia, Pilgrim, Grand Gulf, Fermi, Nine Mile Point, Clinton, Dresden, Browns Ferry, Duane Arnold, Brunswick.

Order to Modify Licenses With Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events

Nuclear Street News — Wed, 14 Mar 2012 13:35:50 GMT

The attached Order gives guidance and strategies if the loss of power, motive force, and normal access to the ultimate heat sink to prevent fuel damage in the reactor and SFP, affected all units at a site simultaneously. This Order requires a three-phase approach for mitigating beyond-design-basis external events. The initial phase requires the use of installed equipment and resources to maintain or restore core cooling, containment, and SFP cooling, The transition phase requires providing sufficient, portable, onsite equipment and consumables to maintain or restore these functions until they can be accomplished with resources brought from off site. The final phase requires obtaining sufficient offsite resources to sustain those functions indefinitely.

The Order has been issued to the following plants: Quad Cities, Ginna, Point Beach, Grand Gulf, Turkey Point, Kewaunee, Watts Bar, St Lucie, Three Mile Island, Robinson, Waterford, Surry, Summer, Sequoyah, Seabrook, Indian Point, Fermi, South Texas, Shearon Harris, Pilgrim, Perry, Oyster Creek, Nine Mile Point, Limerick, Farley, Dresden, Callaway, Wolf Creek, Vermont Yankee, San Onofre, Salem, Palisades, North Anna, Hope Creek, Duane Arnold, Diablo Canyon, Vogtle, Susquehanna, River Bend, Prairie Island, McGuire, Cooper, Comanche Peak, Oconee, Monticello, Hatch, DC Cook, Columbia, La Salle, Fort Calhoun, Clinton, David Besse, Calvert Cliffs, Fitzpatrick, Crystal River, Brunswick, Browns Ferry, Catawba, Byron, ANO, Braidwood, Beaver Valley, Millstone.

Sources of Radiation

Sena — Tue, 05 Apr 2011 18:20:09 GMT

Apart from the amount of radiation a worker may receive while performing work, they will also be exposed to radiation because of the very nature of our environment. All individuals are subject to some natural irradiation even though they may not work with radioactive substances. This natural source of exposure is often referred to as background radiation.

Studies of the nature and origin of this source of exposure to humans have revealed three main components: terrestrial radiation (which includes the radioactivities of the earth's surface, air and water), cosmic radiation, and the naturally occurring radionuclides deposited in the human body. One might add that man-made sources influence the contribution from some of these sources. The amount that each of these factors contributes varies with the locale.

The study of these factors throughout the world is of value for a number of reasons. Foremost among these is that the use of such data provides a basis or standard from which allowable exposure limits for radiation workers may be developed. In areas where the levels are much higher because of larger concentrations of natural radioactive materials, knowledge may be gained about human hereditary effects at these increased levels. Such data are also needed in assessing the impact on, or contribution of a nuclear facility to the existing concentrations in a given area. In the design of buildings and shielding for low-level work, it is of value to know the radioactive contents of the substances used. Often the levels inside a building are higher than those outside of the building because this factor has been neglected.

Radiological Protection Standards

Sena — Tue, 05 Apr 2011 18:17:32 GMT

The task of setting exposure limits is both a vital and yet a very difficult undertaking. It is vital because workers must be protected from the harmful effects of ionizing radiation. It is difficult because of the many factors which enter into the effects which radiation produces. Even though a vast amount of data has been gathered and studied, there are still many areas where much work is needed before firm conclusions can be drawn. Nevertheless, in order to advance in the field of nuclear energy, people must work with radiation. Thus, certain levels must be set which will protect workers from undue exposure.

Radioactivity -n- Radioactive Decay

Sena — Tue, 05 Apr 2011 18:13:12 GMT

As discussed in previous lessons, there are many different kinds of elements. The atoms of these elements are composed of a nucleus surrounded by orbital electrons. The nucleus consists of protons and neutrons. Each element has a specific number of protons, while the number of neutrons may vary, resulting in various isotopes of the same element.

In addition, a slight difference in mass-energy exists between a composite nucleus and the sum of the free-standing nucleons; that difference being the energy that binds the nucleus together. This indicates that each nucleon, i.e., proton or neutron, give up a certain amount of its mass-energy in order for the nucleus to hold together. Because only isotopes exist in nature, this must mean that only specific combinations of neutrons and protons are possible for the existence of the unchanging stable nuclei. Variations from these specific combinations are possible, but the nuclei may not be completely stable. In other words, there may be more energy present in the nuclei of some isotopes than is required to hold them together. With that excess of energy nuclei will not be stable and will, most likely, dissipate it in some manner, in order to become stable.

Stable nuclei will remain unchanged as long as there is no external influence causing them to become unstable. Unstable nuclei, however, will spontaneously emit excess energy and transform into more stable nuclei. Such transformations are independent of external influences such as temperature or chemical reactions of the atom. The emission of excess energy by unstable nuclei in order to achieve stability is the phenomenon of radioactivity.

Radiation Detector Theory

Sena — Tue, 05 Apr 2011 18:10:57 GMT

In all aspects of radiological control, knowledge of the characteristic and magnitude of the radiation field is essential in evaluating the degree of radiological hazard present. Radiation itself cannot be detected directly. Because of this, radiation detection is accomplished by analysis of the effects produced by the radiation as it interacts in a material. Numerous methods of accomplishing this analysis have been developed and implemented with varying degrees of success. Several of these have found extensive application in radiological control.

Nuclear Physics

Sena — Tue, 05 Apr 2011 18:08:17 GMT

Nuclear power is made possible by the process of nuclear fission. Fission is but one of a large number of nuclear reactions that can take place. Many reactions other than fission are quite important because they affect the way we deal with all aspects of handling and storing nuclear materials. These reactions include radioactive decay, scattering, and radioactive capture. This lesson is designed to provide an understanding of the forces present within an atom.

Internal Exposure Control

Sena — Tue, 05 Apr 2011 18:06:23 GMT

Radiological control involves the protection of human population and its environment from the harmful effects of exposure to radiation or radioactive materials. The tasks that make up the responsibilities of the RCT include those actions used to minimize the potential exposure of workers and include efforts at reduction of both internal and external exposures. This lesson is designed to familiarize the technician with those actions necessary to minimize the entry of radioactive materials into the body and the basis for those actions. Major topics include:

Modes of entry into the body
Preventive measures, their use, and their basis
Metabolism of materials and elimination processes
Assessment methods
Definitions.

Interaction of Radiation with Matter

Sena — Tue, 05 Apr 2011 18:01:53 GMT

All radiation possesses energy, either inherently (electromagnetic radiation) or as kinetic energy of motion (particulate radiations). The interaction of radiation with matter transfers some or all of this energy to atoms of the medium through which the radiation is passing. To say that radiation interacts with matter is to say that it is either scattered or absorbed. The mechanisms of energy transfer for radiation are of fundamental interest in the field of radiological health for the following reasons:

Deposition of energy in body tissues may result in physiological injury.
The products of interactions are used in radiation detection systems.
The degree of absorption or type of interaction is a primary factor in determining shielding requirements.

External Exposure Control

Sena — Tue, 05 Apr 2011 17:59:49 GMT

The goal of any radiation safety program is to reduce exposure, whether internal or external, to a minimum. The external exposure reduction and control measures available are of primary importance to the every day tasks performed by the RCT. In this lesson, we will address the DOE and Facility Administrative Exposure limits and the basic methods used for reducing radiation exposure. Various techniques such as time, distance, and shielding that are used to help reduce external exposure controls will be discussed. These techniques are useful to maintain personnel exposure below administrative and federal limits.

Biological Effects of Radiation

Sena — Tue, 05 Apr 2011 17:58:13 GMT

Within a year after Roentgen's discovery of X-rays in 1895, it was learned that exposure to ionizing radiation could lead to biological damage. Since that time, a tremendous amount of research has been done attempting to interpret the reactions that take place from the moment that radiation enters a living cell until some permanent damage is produced. From beginning to end, these initial reactions are probably completed in a millionth of a second, making them very difficult to study. For this reason, it is still not known which of the many chemical or biochemical reactions brought about by ionizing radiation are responsible for initiating biological damage.

ALARA

Sena — Tue, 05 Apr 2011 17:53:58 GMT

All personnel at a facility must be committed to the ALARA philosophy. The RCT can play a major role in establishing and maintaining that commitment by understanding its concepts. This lesson will familiarize the student with the ALARA concepts and the essential components of an effective ALARA program.

Radoilogical Worker II Training Study Guide

Sena — Mon, 04 Apr 2011 20:34:27 GMT

Training for Radiological Workers

SCBA Training

Sena — Mon, 04 Apr 2011 20:22:00 GMT

Upon completion of this course, the participants will demonstrate their knowledge and understanding of the Self-Contained Breathing Apparatus (SCBA) by obtaining a minimum score of 80 percent on the written examination and also by satisfactory completion of a practical exercise as per this lesson material.

Radiological Worker Training

Sena — Mon, 04 Apr 2011 20:19:39 GMT

A nuclear power plant has common potential hazards found in other industrial facilities, but the additional hazard of exposure to radiation exists. Your duties will require you to enter and work in areas where access is controlled for the purpose of protecting you from radiological hazards. Therefore, this training is intended to familiarize you with some procedures and requirements of the nuclear plant and to provide you with the knowledge to work safely around radioactive material. The guidelines provided in ACAD 00-007, "Guidelines for General Employee Training"
have been followed to develop course content.

Radiological Respirator Training

Sena — Mon, 04 Apr 2011 20:13:04 GMT

Upon completion of this presentation, participants shall acknowledge understanding of theengineering controls and work practices to minimize airborne radioactivity, methods for monitoring and recording exposure from airborne radioactivity, and principles of respiratory devices. Understanding of the Radiological Respirator Program will be achieved by passing a written exam with a score of >80%. Initial Training participants shall be required to complete a practical exercise for inspecting, donning, performing a negative pressure test and removing a respiratory device.

Plant Acess Training Requalification - TVA Specific

Sena — Mon, 04 Apr 2011 20:08:19 GMT

Plant Access Training (PAT) is mandatory for all personnel who require unescorted access to TVA NPG plants. PAT is designed for both new employees and personnel already familiar with nuclear power stations. The purpose of PAT is to inform and familiarize personnel with the policies being used. The guidelines provided in Nuclear Energy Institute (NEI) 03-04, Guideline for Plant Access Training, have been used to provide an industry standard for this training.

Plant Access Training Initial -TVA Specific

Sena — Mon, 04 Apr 2011 20:03:16 GMT

The information presented in this lesson plan is identified as being specific to the TVA NPG Plants. This information is also provided in TVA NPG’s Plant Access Training (PAT010) Course. This course is intended for those who already have current equivalent training at another utility and only need the information specific to TVA NPG. The guidelines provided in NEI 03-04, “Guideline for Plant Access Training,” have been used to provide an industry standard for this training.

Foreign Material Exclusion

Sena — Mon, 04 Apr 2011 19:57:35 GMT

Upon successful completion of this course, participants will be able to implement the Nuclear Power Group (NPG) Foreign Material Exclusion [FME] program as detailed in Standard Programs and Process SPP-6.5. In order to demonstrate their knowledge, students must score >80% on a written examination.

Fitness for Duty

Sena — Mon, 04 Apr 2011 19:52:55 GMT

Fitness For Duty (FFD) training is mandatory for all personnel who require unescorted access to Tennessee Valley Authority Nuclear Power Group (TVA NPG) plants and must be completed prior to receiving a picture badge. The purpose of FFD training is to inform and familiarize personnel with polices being used. An examination with a score of greater than or equal to 80 percent is required in order to obtain credit for this course. The guidelines provided in NEI 03-04, “Guideline for General Access Training,” have been used to develop course content. TVA NPG requirements for FFD are contained in SPP-1.2, “Fitness for Duty.”

Vogtle Outage General Employee Training Handbook

Sena — Mon, 04 Apr 2011 19:47:59 GMT

Vogtle Outage General Employee Training Handbook

GE ESBWR Fact Sheet

Sena — Fri, 18 Feb 2011 21:43:05 GMT

GE Hitachi Nuclear Energy’s (GEH) next evolution of advanced Boiling Water Reactor (BWR) technology is the ESBWR. This simplified design provides improved safety; excellent economics; better plant security; a broad seismic design envelope; and operational flexibility that increases plant availability.

Toshiba ABWR Fact Sheet

Sena — Fri, 18 Feb 2011 18:41:57 GMT

The Advanced Boiling Water Reactor (ABWR) is the only advanced nuclear design to have successfully entered operation. It has few of the first-of-a-kind technology risks found with all other advanced nuclear designs. The four ABWR units in commercial operations have been built in between 37 and 43 months from first safety concrete to first fuel load in Japan, and have more than a decade of operating history.

GE ABWR Overview

Sena — Thu, 17 Feb 2011 20:29:01 GMT

The information in this PDF contains the BWR Overview. It also contains information about Containment, Nuclear Steam Supply, Engineered Safety Features, Digital C&I, Miscellaneous Systems, Safety (Core Damage), and Defense in Depth.