Text

Official Exhibit - NYS000138-00-BD01 - Report of Earle Bascom in Support of Contentions NYS-6/7 (2011 Bascom Report)
	ML12334A648
Person / Time
Site:	Indian Point
Issue date:	12/13/2011
From:	Bascom E; Electrical Consulting Engineers
To:	; Atomic Safety and Licensing Board Panel
	SECY RAS
References
	RAS 21545, 50-247-LR, 50-286-LR, ASLBP 07-858-03-LR-BD01
	Download: ML12334A648 (35)
	v • d • e

United States Nuclear Regulatory Commission Official Hearing Exhibit NYS000138 Entergy Nuclear Operations, Inc. Submitted: December 15, 2011 In the Matter of:

(Indian Point Nuclear Generating Units 2 and 3)

ASLBP #: 07-858-03-LR-BD01 Docket #: 05000247 l 05000286 Exhibit #: NYS000138-00-BD01 Identified: 10/15/2012 Admitted: 10/15/2012 Withdrawn:

Rejected: Stricken:

Other:

UNITED STATES NUCLEAR REGULATORY COMMISSION ATOMIC SAFETY AND LICENSING BOARD

x In re: Docket Nos. 50-247-LR; 50-286-LR License Renewal Application Submitted by ASLBP No. 07-858-03-LR-BD01 Entergy Nuclear Indian Point 2, LLC, DPR-26, DPR-64 Entergy Nuclear Indian Point 3, LLC, and Entergy Nuclear Operations, Inc. December , 2011

x REPORT OF EARLE C. BASCOM III, P.E.

IN SUPPORT OF CONTENTIONS NYS-6 and 7

Prepared for the State of New York Office of the Attorney General 2

Report of Earle Bascom III

Table of Contents 1.0 Introduction .....................................................................................................................4 2.0 Background on Underground Cable Systems ................................................................6 2.1 Underground Cable Construction...............................................................................7 2.1.1 Conductor .................................................................................................................8 2.1.2 Conductor Shield......................................................................................................8 2.1.3 Insulation .................................................................................................................9 2.1.4 Insulation Shield......................................................................................................9 2.1.5 Concentric Metallic Shield or Neutral ....................................................................9 2.1.6 Jacket .......................................................................................................................9 2.1.7 Conduits .................................................................................................................10 2.2 Other Major Extruded Cable System Components..................................................10 2.2.1 Terminations ..........................................................................................................10 2.2.2 Splices.....................................................................................................................10 2.3 Cable Failures............................................................................................................10 2.3.1 Manufacturing Defects ..........................................................................................11 2.3.2 Workmanship Defects at Accessories ...................................................................11 2.3.3 Mechanical Damage...............................................................................................11 2.3.4 Thermally Induced Degradation ...........................................................................12 2.3.5 Water Trees and Electrical Trees .........................................................................12 2.4 Cable Tests.................................................................................................................14 3.0 Description of AMPS for non-eq inaccessible cables EXPOSED TO SIGNIFICANT MOISTURE in GENERIC AGING LESSONS LEARNED ("GALL") REPORTS .................15 4.0 Entergys Initial Aging Management Plan for Non-EQ Inaccessible Medium and Low Voltage Cables ...........................................................................................................................20 5.0 Entergy's Amended Aging Management Plan for Non-EQ Inaccessible Medium and Low Voltage Cables ...................................................................................................................21 5.1 Background ................................................................................................................21 5.2 Assessment of Entergy's Amended Aging Management Plan for Non-EQ Inaccessible Medium and Low-Voltage Cables Exposed to Significant Moisture ..............23 5.2.1 Amended AMP Does Not Identify Cable Types....................................................23 5.2.2 Amended AMP Does Not Identify Test Method(s) to be Used.............................24 5.2.3 Amended AMP Does Not Identify Alternative Test Methods .............................25 5.2.4 Amended AMP Does Not Identify Approach to or Use of Trending....................25 5.2.5 Amended AMP Does Not Identify Acceptance Criteria .......................................26 5.2.6 Amended AMP Does Not Identify Corrective Actions .........................................26 5.2.7 Entergy's LRA Does Not Address the Effects of Aging Caused By Thermal Stress on Non-EQ Inaccessible Low and Medium Voltage Cables ..................................27 6.0 Conclusion ......................................................................................................................31 7.0 References ......................................................................................................................32 Appendix A - Earle C. Bascom, III Biography ........................................................................34 3

Report of Earle Bascom III

Review of Entergy's Aging Management Plans for Non-Environmentally Qualified Inaccessible Medium and Low Voltage Power Cables Exposed to Adverse Localized Environments at the Indian Point Energy Center, Units 1 and 2 13-December-2011

1.0 INTRODUCTION

I, Earle C. Bascom, III, Principal Engineer with Electrical Consulting Engineers, P.C., (ECE), have been retained by New York State to review Entergy's Aging Management Plan for non-environmentally qualified inaccessible low- and medium-voltage power cables in the Indian Point 2 and 3 nuclear power plants that are exposed to adverse localized environments and to assess whether Entergy has demonstrated that the AMP will manage the effects of aging of these cables so that they will be able to perform their intended function for another 20 years during the extended licensing period.

ECE is a New York professional corporation providing engineering consulting services to the electric power industry. I earned an A.S. in Engineering Science from Hudson Valley Community College in Troy, New York in 1987, a B.S. and M.E.

in Electric Power Engineering from Rensselaer Polytechnic Institute in Troy, New York in, respectively, 1989 and 1990, and an MBA from the State University of New York at Albany in 1993. I am a licensed professional engineer in the State of New York and have spent my entire 21-year career focusing on underground power cables in the areas of analysis, design, specification, and assessment. I am a member of the Institute of Electrical and Electronics Engineers (IEEE), its Power &

Energy Society, and the Insulated Conductors Committee (ICC) and a voting member of the Standards Association to write, review and approve IEEE guides and standards. I am also a member of CIGRÉ. Appendix A contains my biography.

The Atomic Safety and Licensing Board granted New York State's petition to intervene in the Nuclear Regulatory Commission's relicensing proceeding for IP2 and IP3 and has admitted Contentions 6 and 7 which challenge the adequacy of Entergy's Aging Management Plans ("AMPS") for inaccessible non-environmentally qualified medium and low voltage cables. These AMPS are contained in Entergy's License Renewal Application for the extended operation of the Indian Point 2 and 3 nuclear power plants ("IP 2 and 3") located in Buchanan, in New York State on the Hudson River approximately 24 miles from the New York City border. The present licenses for IP2 and IP3 are due to expire, respectively, in September 2013 and December 2015.

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Figure 1 - Location of IP#2 and IP#3 Plants Due to the significant complexity of nuclear power plants, and the potentially catastrophic effects of failing to adequately control and contain the nuclear energy generation process, New York State seeks to insure that, if IP 2 and IP3 are relicensed, Entergy is adequately managing the aging of non-environmentally qualified ("non-EQ") inaccessible low and medium voltage cables that are exposed to localized adverse environmental conditions so that they continue to perform their intended function for another 20 years during the extended license period. The recent failure of power systems at the Fukushima Dai-ichi nuclear plants in the area near Okuma and Futaba, Japan are examples of why reliable power supply to critical systems in nuclear power plants is essential.

I have reviewed the materials provided by New York State and identified by Entergy as relevant to New York State's contentions about the insufficiency of its aging management programs for non-environmentally qualified, inaccessible low and medium voltage cables that are exposed to localized adverse environmental conditions. I have also reviewed information provided by the NRC Staff, NRC guidance documents and technical reports relevant to these contentions. Attached to this report is a list of the documents I reviewed in reaching my conclusions.

Based on my review of these documents and my twenty-one years of experience related to underground and submarine cable applications and technologies, I have concluded that Entergy's Aging Management Plans for these cables is lacking in substantive detail such that Entergy has not demonstrated that the effects of aging on these cables will be managed during the 20 year period of extended operations so that the cables will perform their intended function. In sum, Entergy does not specify the location or number of the relevant cables, does not identify their 5

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function, or criticality to plant operations, does not describe their physical characteristics, does not identify the cable condition monitoring tests that will be used, does not explain the criteria for determining whether the test results are acceptable, and does not identify what corrective actions, if any, Entergy will take if a defective cable is found. Without this essential detail, Entergy has not demonstrated that the Aging Management Program ("AMP") for non-EQ inaccessible low and medium voltage cables that are exposed to significant moisture will adequately manage the effects of aging during the license renewal period.

In addition, Entergy's LRA contains no plan to manage the effects of other localized adverse environmental conditions, such as excessive heat, on inaccessible non-environmentally qualified cables, and no explanation of why such a plan is not necessary.

In order to fully explain the bases for my conclusion, I have provided background about the construction and function of electric cables, the problems that can arise when inaccessible cables are subject to localized adverse environments that they were not designed to withstand, and which an effective AMP should address and manage, and the way in which the NRC and Entergy have responded to these issues during the course of this proceeding.

2.0 BACKGROUND

ON UNDERGROUND CABLE SYSTEMS An electric current is a flow of electrons through a conductor. A cable conductor is comprised of stranded wires made of copper or aluminum; these materials offer little resistance to the electron flow. In order for an electric current to perform work, the conductor must be part of a circuit through which the current continuously flows.

Voltage from an electric generator produces the force (electromotive force) to move the electrons through the conductor and around an electric circuit. That force is measured in volts and is described as voltage. Electric current is measured in amperes. Electric power, or the work electricity can do, is the product of amperes and voltage and is expressed as watts.

.There are two basic components of an electric cable - the conductor that carries the current and the cable insulation that prevents the electricity in the conductor from discharging into the surroundings. Other components of the cable help assure that these two basic functions are maintained. If insulation is no longer capable of preventing the electricity from discharging into the surroundings, the voltage of the electricity drops, the electrical current faults to ground, the circuit fails and the circuit is then unable to perform its task. In an electric cable, the voltage between the conductor and the outer cable layers is called "line to ground voltage." It represents the electrical potential on the conductor to drive the movement of the electrons. The total power carried by a single cable is the line-to-ground voltage 6

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multiplied by the current, and is expressed as watts (or kilowatts or megawatts in large power systems).

Power equipment is often designated by voltage class which is based on the magnitude of the voltage with which the equipment operates and usually reflects the difference in magnitude of the voltage in two of three cables in three-phase systems (i.e., line to line voltage). Transmission class equipment generally operates at or above 69,000 volts. Distribution class equipment generally operates below 69,000 volts. In a utility setting, medium voltage equipment is a subset of distribution class and usually refers to equipment that operates above 2,400 volts to 69,000 volts. Low voltage equipment refers to equipment that operates at 2,400 volts or less. Low voltage cables are sometimes part of single-phase (as compared to three-phase) circuits.

All underground distribution cables are either medium or low voltage; the main distinction between the two is that low-voltage cables may not contain a metallic shield or concentric neutral to carry charging current, fault current and neutral return current.

Cables may be installed in cable trays or above ground conduits, directly buried underground or pulled through buried or above ground conduits. "Inaccessible cables are directly buried or in buried or above ground conduits where direct visual inspection is not possible, or potentially in areas that people cannot access because of safety or environmental hazards.

Extruded cables are a specific type of power cable, with the extruded referring to the manner in which the insulation material is applied to the cable. "Extruded cables" are most likely the type utilized in the IP2 and IP3 plants. Therefore, the discussion in the following sections focuses on the basic components of an extruded underground cable:

2.1 Underground Cable Construction I created Figure 2 below, which is a composite of pictures from various sources, to illustrate the parts of an insulated power cable. Detailed descriptions of the various components are provided below the figure.

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Figure 2 - Low and Medium Voltage Underground Cable Components 2.1.1 Conductor The conductor (or phase conductor) is a metal, either copper or aluminum, that carries current; as the conductor cross-sectional area increases, the current-carrying capacity of the cable increases because the conductor resistance is reduced. The conductor is usually manufactured using stranded wires that improve flexibility and permit the manufacturer to adjust conductor size (area). Factors that influence the selection of conductor size are required current-carrying capacity and installation conditions such as burial depth, soil characteristics, and ambient temperature.

2.1.2 Conductor Shield While generally smooth, the conductor on a cable has inherent imperfections and non-uniformity that would cause electrical stress in the overlying insulation layer.

To minimize the impact of these imperfections, a thin semi-conducting ( i.e., while the material is neither a good conductor or insulator, it exhibits characteristics that make it partially or semi conducting) layer of material is applied over the conductor to provide a smooth interface with the insulation that will support the 8

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line-to-ground voltage. The main issue is to minimize electrical stress within the insulation.

2.1.3 Insulation The insulation on extruded cables is most often either cross-linked polyethylene (XLPE) or ethylene-propylene-rubber (EPR), sometimes called high molecular weight polyethylene, (HMWPE). Both of these materials are created by combining the necessary chemical components using reagents, heat and pressure in a factory that then pumps (extrudes) the insulation through a die at high temperature over the conductor and conductor shield; the insulation material is then allowed to cool and set. The thickness of the material is a function of voltage with greater voltage requiring a thicker insulation.

XLPE-insulated cable is less expensive to manufacture and is generally more susceptible to damage when exposed to water or moisture as compared to EPR insulation. For this reason, some modern low- and medium-voltage XLPE cables contain a hermetic metallic moisture barrier, similar to that used on high voltage underground transmission cables. More commonly at medium and low voltage, the XLPE insulation contains an additive to the insulation that limits the formation of water trees (sometimes referred to as tree-retardant XLPE or TRXLPE).

2.1.4 Insulation Shield Similar to the conductor shield, a non-metallic insulation shield on a cable provides a smooth interface between the insulation and outer cable layers. The insulation shield is a semi-conducting material similar to the conductor shield.

2.1.5 Concentric Metallic Shield or Neutral Outside the insulation and insulation shield, the cable may include a metallic shield. This is generally a feature of cables with rated voltages above 2.4kV (2,400V) and enhances control of the electrical stress as well as carrying insulation charging current and the return current from the phase conductor. The metallic shield/neutral can consist of helical copper- or aluminum-wire strands, helical copper or aluminum tapes or longitudinal copper or aluminum foil tape (like a cigarette wrap). Some cables have a foil laminate and wires. The longitudinal foil and, to a lesser degree, the helical tapes provide a degree of moisture barrier (i.e., a sheath) to the cable insulation but generally do not form a hermetic seal.

2.1.6 Jacket Over the insulation, insulation shield and/or metallic shield, is an insulating jacket made of polyvinyl chloride (PVC), polyethylene (PE) or other materials, such as 9

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chlorinated polyethylene or chlorosulfonated polyethylene (commercially called Hypalon). The jacket provides mechanical protection to the shield and insulation, prevents corrosion of the metallic shield/neutral, and electrically insulates the metallic shield/neutral from the surrounding environment. Though plastic materials such as PVC inhibit moisture intrusion, they are not a hermetic barrier and do not alone prevent moisture intrusion into the insulation.

2.1.7 Conduits Conduits are used for some cable installations. They provide mechanical protection to the cables and separate the activities of the civil contractor during the construction of the cable circuit (who digs the trenches, installs the conduits and manholes/vaults, backfills, etc.) from the activities of the electrical contractor (who pulls cable, installs joints and terminations, connects other electrical equipment, etc.). Conduits are typically made of polyvinyl chloride (PVC), fiberglass reinforced epoxy (FRE), or metal. Unlike high transmission voltages where single cables are installed in individual conduits, multiple low- and medium-voltage cables may be installed in a common conduit.

2.2 Other Major Extruded Cable System Components In addition to the cable itself, the cable system includes terminations and joints 2.2.1 Terminations A termination is a mechanical component that allows a transition from the power cable insulated with high-dielectric strength materials such as XLPE or EPR insulation, to the relatively low-dielectric strength of air or directly to another electrical component such as a switch, circuit breaker, transformer, motor, pump or valve. At low- and medium- voltages, a termination is generally pre-molded by the manufacturer and then supplied for a given cable size and application.

2.2.2 Splices A splice or joint is constructed where two sections of cable must be joined together.

The most common application of a splice is in a vault, hand-hole or manhole when cables are being installed in conduits. Splices may also be directly buried when connecting cables that are similarly placed directly in the ground.

2.3 Cable Failures In the simplest terms, a failure occurs when a component or apparatus no longer performs its intended function. In this regard, a power cable circuit failure prevents the circuit from carrying power to the intended location or equipment.

Fundamentally, this means that the cable circuit stops carrying current (failure or 10 Report of Earle Bascom III

interruption of the conductor) or stops supporting line-to-ground voltage (failure of the insulation), or both.

A cable conductor failure alone is uncommon. This could result from the inadvertent severing of a cable during a dig-in or the subjection of the cable to longitudinal mechanical forces that damage the conductor without affecting the insulation. However, in the process of severing the conductor, the insulation is also compromised so there is usually a break-down in the insulation accompanied by the break in the conductor.

Most cable failures result from the slow or rapid degradation of the insulation between the conductor and shield that supports the applied line-to-ground voltage, or from a breakdown between cable conductors of the same circuit, the phase-to-phase voltage. Causes for the breakdown in the extruded insulation include:

2.3.1 Manufacturing Defects Quality control in extruded cable manufacturing is essential to the reliable operation of cables. Industry standards and specifications provide guidance on manufacture of extruded cables and accessories. The manufacturer generally performs qualification, routine and sample tests to assure the buyer that a particular cable has met industry standards, and to identify problem cable before it is sold or installed. Many times manufacturing defects not detected at the factory are uncovered when the completed cable system is commissioned or in the first few years of operation.

2.3.2 Workmanship Defects at Accessories The most likely cause of cable failures is workmanship errors associated with installing the joints or terminations. While the cable is manufactured in a controlled factory environment, joints and terminations must be assembled in the field where factors such as training, worker fatigue and environmental conditions at the time of assembly can impact the quality of the completed joints and/or terminations. In most cases, joints and termination failures are in accessible locations, such as substations, equipment cabinets, or vaults and manholes.

2.3.3 Mechanical Damage Conventional buried utility circuits may be inadvertently damaged by dig ins, usually by contractors excavating near the cable circuits. Mechanical damage can be caused by a neighboring circuit that sustains a fault that burns or arcs, commutes to a parallel cable and damages it. Damage of this type may also occur from load cycling (thermal-mechanical bending or TMB) or fatigue from inadequate support when suspended in air or clamped.

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2.3.4 Thermally Induced Degradation Thermally induced degradation occurs when a cable is operated above its rated temperature. Eventually, the insulation may melt or burn causing the dielectric strength (voltage insulating properties) to degrade to the point of an electrical breakdown. Thermal degradation can occur when the environment around the cable does not adequately remove heat. For underground cables, the thermal resistance of the soil through which the underground cable passes may be higher than expected, and thus increase the temperature in the soil surrounding the cable..

In addition, the cable may pass through a localized environment that has a higher ambient temperature than expected. Or external sources, such as heat from other cables in close proximity to the subject cable, particularly in underground conduits, will cause the temperature to rise in the vicinity of the subject cable and cause a mutual heating effect. Other external heat sources, such as a steam line or hot water pipe may also cause the subject cable to operate above its rated temperature.

2.3.5 Water Trees and Electrical Trees Water treeing, or electrochemical degradation, is a phenomenon that was first described in technical references in 1969, (Exhs. NYS000139 through NYS000145).

Water treeing is an electro-chemo-mechanical phenomenon which has caused premature failure of XLPE and EPR cables.

Water treeing occurs in cables that are not constructed to resist water intrusion but are nevertheless wetted or submerged in water for periods of time and exposed to voltage. Electrochemical degradation (i.e., water treeing), which is a precursor to electrical treeing, is the primary cause of unreliability of medium voltage XLPE and EPR cable. High failure rates during the 1970s and 1980s of XLPE and EPR cable led to technical developments to reduce water trees, including dry curing of cable, the installation of semi-conductive shields with substantially reduced ionic content (i.e., materials lacking free ions that could induce water treeing), and eventually, the creation of tree retardant compounds which reduce the insulation's propensity toward water treeing.

Water trees can form in certain insulation materials when water and voltage are present. Water permeates the insulation over time unless a metallic shield prevents the moisture from getting into the cable. Moisture migrating into the insulation may form channels that resemble trees when the cable is energized, i.e.,

exposed to voltage. If the cables are not energized, water trees will not form. Water trees are more likely to occur in unshielded medium than unshielded low voltage cables because of the higher voltage. A cable with a water tree and early stages of electrical trees may still be able to operate even though a degree of partial discharge (i.e. localized electrical breakdown) may occur at the locations where water trees 12 Report of Earle Bascom III

have started to carbonize. Over time, this localized electrical breakdown propagates to further carbonize (e.g., burn) the water tree channels to form electrical trees.

When sufficient electrical trees have formed through the insulation thickness, the insulation will break down (i.e., the cable fails). At this point, the cable will not be able to support voltage and therefore cannot carry current.

Water trees initially form in areas of high electrical stress within the insulation.

For this reason, they usually form in the insulation nearest the cable conductor.

Areas of high electrical stress will also occur around insulation voids or where a contaminant is in the insulation; at these locations a bow tie tree may form (so named because it may resemble a bow tie).

Figure 3 is a photograph I took of a cross-section of cable sample with water trees (dyed to provide contrast) in a thin cable sample; this cable sample had not yet failed. The conductor and outer layers have been removed with only portions of the conductor shield, insulation (containing the water trees) and insulation shield visible.

Figure 3 - Example of water trees in cable insulation Water trees are not visible from the outside of the cable and may not present a problem until the water tree forms an electrical tree; electrical trees eventually will lead to an electrical breakdown of the insulation resulting in a cable failure. In a dry cable environment, water trees cannot occur. Cables, particularly with XLPE insulation of the vintage used at the time the original IP2 and IP3 power plants were constructed have shown high failure rates when subjected to conditions that form water trees. Water trees alone may not result in a cable failure because the 13 Report of Earle Bascom III

water tree does not significantly break down the dielectric strength of the insulation. For this reason, water trees are more difficult to detect than electrical trees which do cause more significant degradation in the insulating properties of the dielectric. The primary means of detecting a problem is either to apply a test that can detect electrical trees in the insulation before the cable fails or a test that drives the cable to failure quickly if there is a defect, so that the cable can be repaired during the testing outage when it is not expected to perform; the goal of this latter method of testing is to force a planned outage rather than experience an unplanned outage.

Electrical trees occasionally form on their own (without water treeing) under certain circumstances such as prolonged operation with an insulation protrusion (portion of the conductor or insulation shield, or a foreign object extends into the insulation) or other manufacturing defect that causes an electrical tree to form.

2.4 Cable Tests Testing cable integrity is an important part of underground cable system operation and maintenance and, if a failure occurs, a repair. Prequalification, routine, sample and commissioning tests are part of the manufacturing and new installation of cable systems. Fault location is a type of test used to find a cable failure. From the standpoint of assessing the condition of an existing, installed cable system, these tests are not particularly relevant.

Maintenance and diagnostic tests assess the condition of a cable system or verify a successful repair; this type of testing is most relevant to assessing the condition of cables such as those installed in IP2 and IP3. Diagnostic tests are used to evaluate the condition of some element of the cable system, such as performing partial discharge detection on the insulation.

Tests of this nature may be withstand type tests where a cable is tested to a certain stress, usually beyond normal stress, to elicit a failure or, in the absence of a failure, in an attempt to assure reliability. The goal of a withstand type test is to control when a failure occurs, if one is to occur.

Diagnostic tests are usually intended to be non-destructive, i.e., application of the test will not damage the cable but only detect a problem.

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3.0 DESCRIPTION

OF AMPS FOR NON-EQ INACCESSIBLE CABLES EXPOSED TO SIGNIFICANT MOISTURE IN GENERIC AGING LESSONS LEARNED ("GALL") REPORTS The NRC has issued three versions of a guidance document entitled Generic Aging Lessons Learned ("GALL"). The GALL Reports list generic aging management reviews of systems, structures and components that may be in the scope of license renewal and identifies aging management programs ("AMPS") that the NRC finds acceptable for managing the aging effects expected during a plant's operation past the expiration date of its original license. The first revision of the GALL in 2005 was in effect when Entergy submitted its LRA. NUREG-1801, Rev. 1, Vol.2, Generic Aging Lessons Learned (GALL) Report (September 2005) ("Sept. 2005 GALL Report"), Exh. NYS00146A-00146D.

The AMP in the 2005 GALL Report for non-EQ inaccessible cables exposed to significant moisture did not include low-voltage cables but proposed monitoring and testing only of medium voltage cables, i.e., 2.4-15 kV; cable testing was proposed at least once every ten years, and inspection of accessible sections of cable in manholes or vaults was proposed at least once every two years. Only cables that were subject to both significant moisture and significant voltage were included in the AMP.

Exposure to "significant moisture was defined as "periodic exposures to moisture that last more than a few days (e.g. cable in standing water)." Sept. 2005 GALL Report at page XI E-8, Exh. NYS00146C. A cable was defined as exposed to significant voltage if it was energized 25% of the time. The initial GALL and its first revision listed insulation power factor, partial discharge and polarization index testing as proven tests for detecting deterioration of the insulation system due to wetting or submergence.

The New GALL Report issued in December 2010 requires inspection, monitoring and testing of both low and medium voltage cables, i.e., all cables between 400 V and 15kV exposed to significant moisture. NUREG-1801, Rev. 2, Generic Aging Lessons Learned (GALL) Report), Final Report (December 2010) ("New GALL"),

Exh. NYS00147A -00147E. The inspection frequency of accessible sections of cable in manholes or vaults is based on plant experience, i.e., past experience with water accumulation over time, and on events such as flooding or heavy rain. Inspections of accessible sections of cables in manholes and vaults are proposed to be done at least annually .Cable testing is proposed at least once every six years. Cables that are exposed to significant moisture are included in the AMP whether or not they are subject to significant voltage. Exposure to "significant moisture" is still defined as "periodic exposures to moisture that last more than a few days (e.g. cable wetting or submergence in water"). New GALL at XI E3-1, Exh. NYS00147D.

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The list of proven tests for detecting deterioration of the insulation system due to wetting or submergence was expanded and now includes, but is not limited to, Dielectric Loss (Dissipation Factor/Power Factor), AC Voltage Withstand, Partial Discharge, Step Voltage, Time Domain Reflectometry, Insulation Resistance and Polarization Index, Line Resonance Analysis, or other testing that is state-of-the-art at the time the tests are performed. New GALL at XI E3-1. Exh. NYS00147D.

In sum, the AMP for inaccessible non-EQ cables in the latest version of the GALL now covers inaccessible low- and medium-voltage cables (i.e. - between 400V and 35 kV ) that are subject to significant moisture whether or not they are subject to significant voltage. It requires more frequent checking of accessible sections of inaccessible cables for water accumulation and requires more frequent cable testing using one or more of an expanded list of testing methods that are proven for detecting deterioration of the insulation system due to wetting or submergence. 1 The New GALL also states that "trending actions are included as part of this AMP, although the ability to trend results is dependent on the specific type of test(s) or inspections chosen." New GALL at XIE3-3, Exh. NYS000147D.

As the GALL notes, trendable results "provide additional information on the rate of cable insulation degradation."

There are two types of trending; relative and statistical. Relative trending evaluates the results of tests on the same cable over time in an effort to determine if the cable insulation has degraded between tests or if its condition has remained essentially the same. Statistical trending evaluates test results on a sample of a larger group of similar cables, usually when time or resources are inadequate to test all members of a group. The performance of that sample on a given test is assumed to characterize the performance of the entire group of similar cables. Some examples of relative and statistical trending are highlighted in the method descriptions below.

A summary description of the test methods listed in the GALL is set forth below.

All of these methods require taking the cables out of service to perform the test, and each test has some limitations or disadvantages:

1 These methods, and others, are described and their advantages and disadvantages analyzed in an NRC guidance document published in January 2010, approximately one year before the new GALL was issued. That guidance document, NUREG/CR-7000, is titled Essential Elements of an Electric Cable Condition Monitoring Program. Exh. NYS000148.

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x Insulation (dielectric) Dissipation Factor - This test compares the characteristics of the cable insulation (dielectric) material to that of a near-perfect dielectric using a standard capacitor and a capacitive bridge. The capacitive bridge is used to determine the dissipation factor through the known capacitance of a standard capacitor with that of the unknown capacitance of the cable. The test is most beneficial on paper-insulated cables that have appreciable dielectric losses. This particular test only detects gross defects of the cable, i.e., characteristics that affect the bulk of the cable insulation but does not find localized problems. The test is generally non-destructive. However, it is performed with rated or higher voltage, so it is possible that the cable may fail during the test.

The results of this test can be trended based on relative performance --

that is, by comparing test results at one time to previous test results to see if the dissipation factor is increasing as the insulation ages and whether that increase begins to accelerate closer to the end of cable life.

Statistical trending is also possible with this method.

x AC Voltage Withstand - This type of test subjects the cable to a voltage at or above the voltage that the cable was designed to withstand.

Either the cable will withstand the increased voltage or it will fail due to a defect in the insulation. The failure, if there is one, will occur under controlled conditions, i.e., when planned around the test rather than failing when the cable is in service and expected to perform. This type of test is destructive because the cable cannot be put back in service if it fails the test. In addition, even it a cable passes the test, its insulation may be degraded from the test, rendering it more vulnerable to failure in the future. This type of test is analogous to a medical stress test in that the test specimen is subjected to rigors above what might normally occur; if the cable passes, it can reasonably be assumed that under normal conditions, it will continue to operate successfully, at least for a period of time.

The results of such a pass/fail test cannot be effectively trended based on relative performance from test to test on the same cable because there is no relative measure of performance.

However, statistical trending may be performed by results obtained on a sample of cables of all the cables available for testing. Additional insight may be obtained by first grouping cables before doing tests on a sample of each group. Groupings may be based on characteristics including 17 Report of Earle Bascom III

vintage, manufacturer, insulation type, location within the plant, installation conditions.

x Partial Discharge Detection - This test detects the minute electrical noise (partial discharge or "PD") that is generated where localized breakdowns are occurring in electrical equipment. The test is conducted at rated or, sometimes, higher voltage. As the voltage is raised, localized breakdowns in the insulation - called partial discharge - generate a signal that can be detected from the end of the cable. The test takes advantage of the propagation velocity of the signal through the cable to determine the location within a cable that the PD is occurring- i.e., in a specific location within the cable, or in a joint or termination. The magnitude of the signal detected reflects the extent of the partial discharge. Because the signals being measured are minute, the test equipment and method are sensitive to electrical interference near where the test equipment is used. Also, loss of the minute signal to be detected occurs more readily in unshielded cables so it is a less effective method for unshielded cables or ones where a helically taped shield has aged causing attenuation. The test itself is not destructive, but it is carried out with rated or, perhaps, higher voltage applied to the cable system so there is the possibility that the cable could be damaged.

Relative performance trending with this method is possible from test to test on the same cable because partial discharge occurring in an area that had not previously shown a problem may indicate increased cable insulation degradation. Statistical trending is also possible.

x Step Voltage Test - The step voltage test uses a direct current (DC) voltage. The voltage is raised in stages and the leakage current is monitored during the test to determine if there are problems in the insulation. In general, DC testing of extruded XLPE insulated cables is not recommended based on research done by the Electrical Power Research Institute ("EPRI") and others that shows a higher incidence of failures in service-aged cable exposed to DC tests. As such, this test probably should not be used except for testing of paper-insulated cables.

x Time Domain Reflectometry (TDR) - In this method, a signal is sent through the cable from one accessible cable end; the magnitude and timing of reflections returned to the test equipment gives a measure of the insulation impedance characteristics; the cable propagation velocity is used by the test equipment to determine the location of the impedance. The test is not destructive because the signals sent through the cable are not known to cause damage. While a degrading insulation condition might take time to develop, this test does not necessarily 18 Report of Earle Bascom III

provide any sort of prediction of performance.

Relative performance trending by repeated testing of the same cable is possible since test results from subsequent tests may be compared to prior tests. Statistical trending may also be done.

x Line Resonance Analysis - This method of testing is under development. Information claimed about the method indicate it could be performed without taking the cable system out of service if appropriate sensors are already in place, but only cables so instrumented are available for evaluation. Also, it appears as though the method is non-destructive.

Monitoring methods not considered, but not excluded, in the new GALL include the following:

x Very Low Frequency (VLF) testing has the advantage that test equipment is generally portable and avoids the potential damaging effects of applying DC voltage to an extruded cable. The test is a more effective test than the AC voltage withstand test because it more effectively converts water trees to electrical trees during the time the voltage is applied. As set forth earlier, water trees do not necessarily cause a breakdown in the dielectric strength of the cable to failure, while an electrical tree does reduce the dielectric strength. The benefit of effectively converting a water tree to an electrical tree during the test is to better force weakened insulation to fail during the outage so that a repair can be scheduled when the cable is not in operation. Like the AC withstand test, VLF can be applied to unshielded cables. The test is destructive in that if the cable fails the test, it must be repaired or replaced.

The results of such a pass/fail test cannot be effectively trended based on relative performance from test to test on the same cable because there is no relative measure of performance.

However, statistical trending may be performed.

x Damped AC Voltage (DAC) uses the cable capacitance and an inductive reactor to generate a voltage that can be used for cable testing. As with any of the voltage withstand tests, application of the method may cause a failure.

Relative performance trending is not effective but statistical trending can be performed.

19 Report of Earle Bascom III

The above summary indicates that no individual method is ideal for condition monitoring of inaccessible cables. Partial discharge detection (PD) and TDR can be used on shielded cables (i.e., medium voltage), but taped metallic shields tend to deteriorate over time resulting in less effective tests; wire shielded cables could be tested more effectively over time.

PD provides more extensive information about cable insulation degradation caused by water trees and other forms of insulation degradation than TDR, although both could indicate problems within the insulation system.

Unshielded (low voltage) cables cannot be tested effectively with TDR or PD because the signal loss (attenuation) is too significant, particularly for longer cable circuits. Very low frequency (VLF) testing is more appropriate for low voltage cables that do not include a metallic shield. The VLF test is effective because it drives a weakened cable to failure more quickly than power frequency voltage, helping to identify problematic cables. However, a cable can be damaged even if it passes the VLF, step voltage (or variations such as Damped AC) or AC withstand tests, because the test only confirms that the breakdown voltage of the damaged section at the time the test was conducted is greater than the test voltage applied; the test does not establish anything about the cable's future performance even though it may be reasonable to assume that it will operate successfully at normal voltage for some time into the future. The applied voltages are also often above rated voltage, so there is the possibility that applying the test may further damage weakened areas of the cable system causing incipient failures. The intent with these types of tests is to avoid an unscheduled or unplanned outage by driving an existing defect to failure during the time of the test (30-60 minutes).

Low voltage cables do not have shields and jackets, so the insulation of the cable may effectively be the surface of the cable. Embrittlement (degradation due to heat or radiation) of the cable insulation could be visible from the surface of the cable.

Embrittlement combined with mechanical movement of an affected cable could cause the cable to lose the integrity of the insulation and fail. Visual inspection might be appropriate for accessible sections of otherwise inaccessible cables.

However, this would not provide conclusive proof of the integrity of cables in inaccessible areas.

4.0 ENTERGYS INITIAL AGING MANAGEMENT PLAN FOR NON-EQ INACCESSIBLE MEDIUM AND LOW VOLTAGE CABLES Entergys April 30, 2007 license renewal application for IP2 and IP3 ("LRA"),

contained the following AMP for the aging management of non EQ inaccessible medium voltage cables:

20 Report of Earle Bascom III

In scope medium-voltage cables (cables with operating voltage from 2kV to 35kV) exposed to significant moisture and voltage will be tested at least once every ten years to provide an indication of the condition of the conductor insulation. The program includes inspections for water accumulation in manholes at least once every two years. LRA Section B1.2.3 NUREG-1801 Consistency The Non-EQ Inaccessible Medium-Voltage Cable Program will be consistent with the program attributes described in NUREG-1801,Section XI.E3, Inaccessible Medium-Voltage Cables Not Subject To 10 CFR 50.49 Environmental Qualification Requirements.

The initial LRA contains no AMP for inaccessible low-voltage cables and no other detail about the AMP for medium voltage cables.

New York State's Contentions 6 and 7 challenged the adequacy of this AMP.

In opposing Contentions 6 and 7, the NRC Staff argued that Entergy satisfied 10 CFR § 54.21(a)(3) by agreeing to develop a program that incorporates the GALL's attributes and was not required to include the actual AMP in its LRA. Indeed, the Staff acknowledged that Entergy had not submitted an actual AMP for non-EQ inaccessible medium voltage cables.

In admitting Contentions 6 and 7, the Board rejected the position of NRC Staff and stated that "we do not comprehend how a commitment to develop a program can demonstrate that the effects of aging will be adequately managed."

5.0 ENTERGY'S AMENDED AGING MANAGEMENT PLAN FOR NON-EQ INACCESSIBLE MEDIUM AND LOW VOLTAGE CABLES 5.1 Background After the initial GALL was issued in 2000, the NRC learned that some cables that were qualified for 40 years were failing before the end of their qualified life. The NRC conducted a detailed review of the problem and issued a Generic Letter in 2007 to all current licensees, informing them that "in the absence of adequate monitoring of cable insulation, equipment could fail abruptly during service, causing plant transients or disabling accident mitigation systems" NRC Generic Letter 2007-01: Inaccessible or Underground Power Cable Failures That Disable Accident Mitigation Systems or Cause Plant Transients (Feb. 7, 2007) ("Generic Letter 2007-01") at 1, Exh. NYS000149. Generic Letter 2007-01 also asked 21 Report of Earle Bascom III

licensees to provide a history of inaccessible or underground power cable failures for all voltage cables and to describe their inspection, testing and monitoring programs to detect the degradation of inaccessible or underground cables.

After obtaining licensee responses to the Generic Letter, the NRC issued the new GALL in 2010, with its more stringent requirements for cable testing and manhole inspections.

Entergy did not initially amend its AMP in response to the new GALL.

Finally, on February 10, 2011, the NRC issued a request for additional information

("RAI") asking Entergy to explain how it will manage the effects of aging in inaccessible low-voltage cable and to show that the proposed frequency of manhole inspections and cable testing in its proposed AMP for non-EQ Inaccessible Medium Voltage Cables "incorporate recent industry and plant-specific operating experience for both inaccessible low and medium voltage cable." NRC Request for Additional Information for the Review of the Indian Point Nuclear Generating Unit Number 2 and 3 (Feb. 10, 2011)("RAI") at 6, Exh. NYS000150.

In response to the RAI, Entergy committed to follow the recommendations of the latest GALL and it amended its LRA to incorporate those commitments. Entergy Responses to Request for Additional Information for the Review Of The Indian Point Nuclear Generating Unit Number 2 and 3, NL-11-074 March 28, 2011 ("Entergy March 28 Response") Exh. NYS000151; NL-11-090 July 14, 2011 ("Entergy July 14 Response") Exh. NYS000152; NL-11-090 July 27, 2011 ("Entergy July 27 Response") Exh. NYS000153 and NL 096 ("Entergy Aug.9 Response") Exh.

NYS000154. The amended AMP, with Entergy's edits revealing the changes at page 12 of Entergy's March 28 Response, is set forth below. Exh. NYS000151.

B.1.23 NON-EQ INACCESSIBLE MEDIUM-VOLTAGE CABLE Program Description The Non-EQ Inaccessible Medium-Voltage Cable Program is a new program that entails periodic inspections for water collection in cable manholes and periodic testing of cables. In scope medium voltage cables (cables with operating voltage from 2kV to 35kV) and low-voltage power cables (400 V to 2 kV) exposed to significant moisture and-voltage will be tested at least once every ten six years to provide an indication of the condition of the conductor insulation. Test frequencies will be adjusted based on test results and operating experience. The program includes inspections for water accumulation in manholes at least once every two years-(annually). In addition to the periodic manhole inspections, inspection for event-22 Report of Earle Bascom III

driven occurrences, such as heavy rain or flooding will be performed. Inspection frequency will be increased as necessary based on evaluation of inspection results.

5.2 Assessment of Entergy's Amended Aging Management Plan for Non-EQ Inaccessible Medium and Low-Voltage Cables Exposed to Significant Moisture Entergys amended aging management plan for non-environmentally qualified inaccessible low- and medium-voltage cables does not provide a specific plan that demonstrates that Entergy will adequately manage the effects of aging on non-EQ inaccessible low and medium voltage cables exposed to significant moisture and thus insure that the cables can perform their intended function during the 20 years of extended operation. Although Entergy has generally committed to follow the New GALL, it does not select appropriate test methods, or test acceptance criteria or corrective actions from among those listed in the new GALL, nor does it identify or justify any criteria it will use for making these selections. I have identified the following areas of concern in this regard.

5.2.1 Amended AMP Does Not Identify Cable Types The Brookhaven National Laboratory (NUREG/CR7000) noted in its report prepared for the NRC, that "once a decision is made to perform more intrusive testing, the characteristics of the cable to be monitored must be considered in selecting an appropriate technique." Some of the relevant cable characteristics identified by Brookhaven include cable voltage rating, cable insulation/jacket material, cable shielding and cable location. NUREG/CR 7000 at 3-20, Exh.

NYS000148.

However, the amended AMP does not identify the non-EQ inaccessible cables or their characteristics. Without the cables and their characteristics identified, the Board cannot assess if the aging management plan can adequately detect problems with these cables and appropriately manage the condition of the cables. If Entergy has not yet inventoried the non-EQ inaccessible cables within IP2 and IP3, it cannot prepare a specific program for the management of their aging. If Entergy has done this inventory, the results should be included in the amended AMP.

Similarly, the presence of a metallic shield or not and the type of shield would determine if certain methods such as PD or TDR testing can be applied affectively or not.

23 Report of Earle Bascom III

In addition to identifying the cable types, the number of cable circuits, installation conditions of cables, and cable circuit lengths would determine if some methods could be used.

Knowing the number of relevant circuits would assist in evaluating whether Entergy will be able to fulfill the commitment in its revised AMP to test all of them at least once before the period of extended operation begins. Entergy March 28 Response at 12, Exh. NYS000151. The current license for Indian Point 2 expires in September 2013, which is less than two years from the date of this report.

Depending on the accessibility of the cables, locations of terminals, and calibration of equipment, three to five partial discharge tests might be performed in a normal work day allowing time for setup. Similarly depending on accessibility, five to ten voltage withstand tests might be performed in a day.

Because Entergy has not specified the number of relevant cables, it is not clear that it has planned for a sufficient number of days of planned outage to accomplish the task of testing all the cables by the time the current IP 2 license expires.

Entergy has therefore not demonstrated that it will be able to test all the relevant cables before the period of extended operation.

5.2.2 Amended AMP Does Not Identify Test Method(s) to be Used Because Entergy has not identified the physical characteristics of the relevant cables, its amended AMP does not identify the test methods that will be used to assess the condition of the cables. For example, I have presumed in this report that the cables used in the IP2 and IP3 plants are of extruded construction. However, if some or all of the cables are paper-lead, another distribution cable type that was frequently used by utilities in the 1960s and 1970s and continues to be used by some utilities today, then DC Hi-Pot, Step Voltage and Insulation Dissipation Factor Measurement would be appropriate for these cables but not for most extruded cables.

As another example, if Entergy intends to use partial discharge detection on unshielded cable and the cables are more than a few hundred feet long, the test results will be ineffective or, at a minimum, misrepresent that partial discharge is not occurring when it is -- i.e. a false negative. Similarly, if Entergy selects Step Voltage, which uses a DC voltage, for testing on XLPE-insulated cable, the test method might induce additional cable failures.

The Board must know before Entergy's license is renewed what test methods Entergy will use for what types of cable. Without that information, the Board cannot determine whether the selected test method(s) is (are) effective for type(s) of cable installed in the plant.

24 Report of Earle Bascom III

5.2.3 Amended AMP Does Not Identify Alternative Test Methods The New GALL's list of appropriate test methods is not exclusive. It does not include VLF testing, which can be quite effective in assessing the condition or at least the continued functionality of low voltage unshielded XLPE cables. Because Entergy simply states that its AMP will be implemented consistent with the attributes of the New GALL, and the New GALL does not list VLF as a testing method, the Board cannot know whether Entergy will reject VLF simply because it is not listed in the New GALL.

5.2.4 Amended AMP Does Not Identify Approach to or Use of Trending Although the NRC recognizes that the ability to trend test results depends on the specific type of test, it nevertheless includes trending actions as part of the AMP in the New GALL. New GALL at XIE3-3, Exh. NYS00147D.

Test results are trendable if later test results can be compared to earlier ones so that the cable's relative performance on the test over time can be obtained. As the New GALL states, trendable test results "provide additional information on the rate of insulation degradation." Armed with that information, Entergy might be able to repair or replace cables before they failed.

Entergy does not mention trending at all in the revised AMP despite its significance.

Because trending is a part of the New GALL's AMP for non-EQ inaccessible low and medium voltage cables, Entergy should select tests with trendable results wherever possible. For example, VLF or AC Withstand tests are pass/fail. Their results cannot be trended from test to test because they do not reveal anything about the extent of cable degradation at the time of the test. By contrast, the results of PD or TDR testing can be trended from test to test on the same cable because partial discharge or changes in cable impedance shown on a TDR trace occurring in a new area in a later test may indicate increased cable insulation degradation.

25 Report of Earle Bascom III

5.2.5 Amended AMP Does Not Identify Acceptance Criteria Because Entergy has not identified which test methods it will use, it cannot identify the acceptance or pass/fail criteria it will use for whatever tests it eventually selects. The board thus cannot assess what will constitute a successfully passed test with one that will not.

Thus it cannot be determined whether Entergy will interpret the test results according to acceptance criteria that leave degraded cables in place that should be replaced or repaired. For example, if Entergy plans to use AC Voltage Withstand or VLF testing on particular cables, but has not specified what test voltages it will use on each of the cables based on their respective voltage classes, Entergy could apply a voltage below the cable's rated voltage so that a passing grade would be meaningless.

Similarly, in the Partial Discharge Test, the partial discharges that occur at the location of degraded insulation are measured in picocoulombs. If Entergy applies the PD test to certain cables, it must explain what level of picocoulomb discharge is acceptable and what level is not. Otherwise, Entergy could select as an acceptance criterion, an unusually high partial discharge level that allowed degraded cables to pass the PD test that would otherwise fail if an appropriate acceptance criterion were selected.

5.2.6 Amended AMP Does Not Identify Corrective Actions Preventing cable insulation degradation in the first instance is a more effective aging management program than testing the condition of cables whose insulation has already degraded and determining whether to replace them. Because water trees in cable insulation cannot form in the absence of water, and electrical trees do not generally form in the absence of water trees, a robust program for preventing water accumulation in the raceways is essential.

The new GALL lists some corrective measures such as installation of permanent drainage systems, installation of sump pumps and alarms, more frequent cable testing or manhole inspections or replacement of the affected cable but provides no guidance about when one or the other of these measures is necessary. New GALL at XI E3-2, Exh. NYS00147D. In its AMP, Entergy does not describe or commit to any of these corrective measures and does not explain when its response will simply be more manhole inspections as opposed to measures that will actually prevent these non-EQ cables from being exposed to significant moisture. Entergy has not demonstrated that it will adequately manage the effects of aging if there remains the possibility that it will do nothing to prevent cables from being repetitively exposed to significant moisture.

26 Report of Earle Bascom III

Moreover, if flooding cannot be substantially prevented with permanent drainage systems or sump pumps, Entergy does not indicate that cables installed in those areas will be replaced with cables qualified to operate in wet environments.

Similarly, in the event a cable fails a condition monitoring test, Entergy's amended AMP does not identify how the cable problem will be addressed. Corrective actions in the New GALL include, but are not limited to more frequent testing, or replacement of cables.

Entergy must explain whether, and under what circumstances, Entergy will select more frequent testing as the corrective action instead of cable replacement and whether replacement cables will be environmentally qualified to be submerged in water.

Thus, when cables fail a voltage withstand test, at a minimum, the section of the cable that failed must be replaced. Other corrective options include replacing the entire cable or replacing the entire cable circuit. In addition, submarine cable that is impervious to water intrusion could be used as a replacement instead of newer XLPE cable in which the possibility of water trees has been reduced but not eliminated. Entergy must explain its criteria for selecting one of these corrective measures over another and must establish that those corrective criteria will assure that the cables continue to perform their intended function.

5.2.7 Entergy's LRA Does Not Address the Effects of Aging Caused By Thermal Stress on Non-EQ Inaccessible Low and Medium Voltage Cables Entergy has not provided an AMP for inaccessible cables exposed to localized adverse environments such as excessive heat, nor has it demonstrated that there are no inaccessible cables at IP 2 and IP3 exposed to excessive heat. It has thus failed to demonstrate that the effects of aging will be adequately managed.

First, thermal degradation of cables can result in failures of cable systems. This has occurred at utilities, with some cases publicly documented. For example, in 1988, a power outage caused by thermal degradation of cables occurred in Auckland, New Zealand and left the central business district with minimal power for several weeks and with power restrictions for another month. Inquiry into The Auckland Power Supply Failures: Technical Report -Cable Failures , Integral Energy Australia, May 5, 1998, Exh. NYS000155. Second, adverse temperature conditions may exist for cables in inaccessible locations. Because there is uncertainty about the installation environment of inaccessible cables or the mutual heating that can occur among cables installed in close proximity underground, the effects of adverse temperature must be considered in any AMP for inaccessible cables.

27 Report of Earle Bascom III

Section XI.E1 of the new GALL contains an AMP for non-EQ accessible cables that are exposed to "adverse localized environments caused by temperature, radiation or moisture." New GALL at XI E1-1, Exh. NYS00147D. In this AMP, the NRC recognizes that an adverse localized environment caused by heat may exist in inaccessible cables, but only suggests that "if an unacceptable condition or situation is identified for a cable or connection in the inspection, a determination is made as to whether the same condition or situation is applicable to inaccessible cables or connections." Thus, Entergy's adoption of this AMP does not constitute a specific plan to manage the effects of excessive heat on inaccessible cables.

Adverse temperature conditions can occur in any circumstance that causes the cable temperature to exceed the normal rated temperature of the cable system for an extended period of time. A cable's rated temperature (e.g., 90°C for XLPE and EPR cables) is based on its ability to operate for a sustained period of time under certain loading and environmental conditions. The length of time it takes for cables exposed to excessive heat to degrade or fail depends on the severity of the actual operating temperature as compared to the cables' rated temperature.. A cable that is operating slightly above rated temperature, say 95°C, would not be expected to experience insulation degradation as quickly as one that is operated at, say 125°C.

The same cable with conditions that result in a temperature of 150°C may degrade to failure within days to months. Cables have a long thermal time constant.

Because of this characteristic, the conditions that would result in extra-normal temperature must persist for an extended period of time or be significantly severe for a problem to occur.

Cable systems, including selection of conductor size, are normally designed to avoid having the cables operate above their rated temperature. Circumstances where there is extra-normal temperature are usually inadvertent because some condition or circumstance was not fully evaluated or loading patterns have changed over time Extra-normal cable temperatures can occur if one of the following conditions related to the environment in which they are installed happens:

x Thermal Resistance of Environment - Basic heat transfer for underground cables is by thermal conduction. When heat passes through a thermal resistance, it results in a temperature rise. For example, buried cables are installed in soils with thermal resistivity characteristics. If Entergy assumes the soil thermal resistivity is lower than it actually is, the cable operating temperature will be greater than expected. The heat source causing the interaction with the environment comes from heat losses when cable current flows through the electrical resistance of the cable conductor and, if present, the metallic shield.

x External Heat Sources - Cables in the vicinity of a subject cable will produce heat when carrying current. These cables will cause a temperature rise in the 28 Report of Earle Bascom III

vicinity of the subject cable, resulting in mutual heating. The extent of mutual heating depends on the number of external heat sources, proximity to the subject cable, amount of electrical current flowing in the cables and the thermal resistance of the environment.

x High Ambient Temperature - The temperature of a cable depends directly on the ambient temperature in which it is installed plus any temperature rise caused by external heat sources and heat from the subject cable passing through the thermal resistance of the environment. If the ambient temperature is higher than expected, the cable will be operating at a higher temperature.

Since a cable rated at 90ºC can degrade to failure within days to months if exposed to a temperature of 150°C, cable testing every six years of inaccessible cables may be insufficient to assure that cables exposed to substantially excessive heat will continue to perform their intended function during the period of extended operation.

In addition to condition monitoring tests on a six year schedule, tests that can detect hot spots on inaccessible cables at an early stage, before serious cable degradation occurs, are critical to prevent a sudden cable failure that may compromise safety. There are two such tests available.

x Distributed temperature sensing (DTS) using a fiber optic sensor is a method that can determine if there are hot spots on inaccessible cable. However, the method requires that a special fiber be installed along with the cables to be evaluated, and retrofitting a fiber into occupied conduits may be difficult. The test provides temperature readings along the length of the cable approximately every 3.3ft (1m).

The test can be trended in that if a hot spot is developing in a cable and appears to becoming worse with respect to time and between tests, the results may be compared and evaluated. Statistical trending may also be applied by, for example, installing the fiber optic sensor in a sample of conduits in which the cables are located and then inferring from the test results, that similar conditions exist in cable installations with similar characteristics that do not have a fiber installed.

x Discrete thermocouple temperature monitoring at known hot spots can also be used at inaccessible locations as an alternative to thermographic testing on accessible cables. The test is less comprehensive than DTS testing and requires an advance determination of the critical locations where the sensors should be installed. As the NRC has noted, that advance determination can be based on a review of Environmental Qualification (EQ) zone maps that show radiation levels and temperatures for various plant areas, consultations with plant staff who are cognizant of plant conditions, and a review of relevant plant-specific and 29 Report of Earle Bascom III

industry operating experience The results for thermocouple temperature monitoring can be compared from test to test.

Power cables have emergency operating temperature limits intended to address short incursions above rated temperature and load. If failed DTS or discrete temperature tests indicate that cables are consistently operating at temperatures above their short-term "emergency" operating limits, then corrective actions must be taken. Those actions include, but are not limited to, removing additional thermal insulation that may be placed around the cables, reducing the number of cables installed in close proximity (to mitigate mutual heating), replacing existing cables with larger conductor cables to decrease heat losses, lowering the ambient temperature in which the cables are installed, and replacing high thermal resistivity soils around the cable conduits or direct buried cables with a lower thermal resistivity thermal backfill.

Degradation of cables caused by excessive heat is not a hypothetical problem. The Sandia National Laboratory commissioned a study entitled Aging Management Guideline for Commercial Nuclear Power Plants - Electrical Cable and Terminations, SAND96-0344. The study report was issued in 1996 and concluded that "thermal embrittlement of insulation is one of the most significant aging mechanisms for low-voltage cable." SAND96-0344, Aging Management Guideline for Commercial Nuclear Power Plants - Electrical Cable and Terminations (September 1996) at 1-3, Exh. NYS00156A.

Because all the safety-related power cables at IP 2 and 3 are low-voltage, Entergy's failure to explain how it will manage the effects of excessive heat on the insulation of non-EQ inaccessible low-voltage cables is a critical omission from its License Renewal Application. Without such a plan, Entergy has failed to demonstrate that its safety-related low-voltage power cables will continue to perform their critical function during the period of extended license operations.

30 Report of Earle Bascom III

6.0 CONCLUSION

Entergy's AMP is lacking in substantive detail, and thus has fails to demonstrate, as required for a renewed license, that the AMP will manage the effects of aging of non.EQ inaccessible cables exposed to significant moisture or excessive heat so that they will be able to perform their intended function for another 20 years during the extended licensing period of operation.

The following specific critical details are missing from Entergy's LRA

Age of the cable circuits

The number of cable circuits

The lengths of cable circuits

The voltage class of the cables

The types of cables, including insulation type

The types of testing that will be performed

The acceptance criteria for each of the tests

The corrective actions

The management of the effects of aging due to t hermal stress

Justification for failing to consider aging due to thermal stress Because of this absence of substantive detail, the licensing board cannot adequately assess if Entergy's LRA should be approved for the continued operation of IP2 and IP3.

December 13, 2011 Sc~ectady , New York

~~ ...:.-.

Earle C. Bascom III, P.E.

President I Principal Engineer Electrical Consulting Engineers, P.C.

4037 Ryan Place* Suite 216 Schenectady, New York 12303 (518) 357*4550 r.bascom@ec-engineers.com 31 Report of Earle Bascom III

7.0 REFERENCES

1. T. Miyashita, Deterioration of water-immersed polyethylene coated wire by treeing, in Proc. IEEE-NEMS Electrical Insulation Conf., 1969, pp. 131-135.

2. L. A. Dissado, Electrical Degradation and Breakdown in Polymers. London, U.K.: Peter Peregrinus, 1992, p. 19.

3. S. A. Boggs, J. Densley, and J. Kuang, Mechanism for impulse conversion of water trees to electrical trees in XLPE, IEEE Trans. Power Del., vol. 13, no.

2, pp. 310-315, Apr. 1998.

4. C. T. Meyer and A. Chamel,Water and ion absorption by polyethylene in relation to water treeing, IEEE Trans. Elect. Insul., vol. EI-I5, no. 5, pp.

389-393, Oct. 1980.

5. R. Ross, Water treeing theoriesCurrent status, views and aims, in Proc.

Int. Symp. Electrical Insulating Materials, 1998, pp. 535-540.

6. N. Hampton, R. Hartlein, et. al., Long-Life XLPE Insulated Power Cable, Jicable, 2007.

7. W. Shu, S. Boggs, Effect of Cable Restoration Fluid on Inhibiting Water Tree Initiation, IEEE Transactions on Power Delivery, Vol. 26, No. 1, January 2011.

8. Essential Elements of an Electric Cable Condition Monitoring Program, U.S. Nuclear Regulatory Commission, NUREG/CR-7000, January 2010.

9. Effect of DC Testing on Extruded Crosslinked Polyethylene Insulated Cables, Electric Power Research Institute, TR-101245, October 1995.

10. W. Vahlstrom, Putting Hipot Out to Pasture, EC&M, October 2003.

11. Medium-Voltage Cables in Nuclear Plant Applications - State of Industry and Condition Monitoring, Electric Power Research Institute, 1003664, October 2003.

12. Plant Support Engineering: Aging Management Program Guidance for Medium-Voltage Cable Systems for Nuclear Power Plants, Electric Power Research Institute, 1020805, June 2010.

32 Report of Earle Bascom III

13. Inquiry into The Auckland Power Supply Failures: Technical Report -Cable Failures , Integral Energy Australia, May 5, 1998.

14. "Aging Management Guideline for Commercial Nuclear Power Plants -

Electrical Cable and Terminations," Sandia National Laboratory, SAND96-0344

15. NUREG -1801 Revision 1 Volume 2 September 2005

16. NUREG -1801 Revision 2 Final Report December 2010

17. NRC Generic Letter 2007-01, February 7, 2001

18. Request For Additional Information For The Review Of The Indian Point Nuclear Generating Unit Number 2 and 3 (February 20, 2011)

19. Entergy Response to Request for Additional Information for the Review Of The Indian Point Nuclear Generating Unit Number 2 and 3, NL-11-032 (March 28, 2011)

20. Entergy Response to Request for Additional Information for the Review Of The Indian Point Nuclear Generating Unit Number 2 and 3, NL-11-074 (July 14, 2011)

21. Entergy Response to Request for Additional Information for the Review Of The Indian Point Nuclear Generating Unit Number 2 and 3, NL-11-090 (July 27, 2011)

22. Entergy Response to Request for Additional Information for the Review Of The Indian Point Nuclear Generating Unit Number 2 and 3, NL-11-096 (August 9, 2011) 33 Report of Earle Bascom III

APPENDIX A - EARLE C. BASCOM, III BIOGRAPHY 34 Report of Earle Bascom III

~ ELECTRICAL CONSULTING ENGINEERS, P.C.

EARLE C. (RUSTY) BASCOM, 111- PRINCIPAL ENGINEER Rusty Bascom holds a Bachelor's of Science (1989) and Master's of Engineering (1990) degrees in Electric Power Engineering from Rensselaer Polytechnic Institute. He also holds an A.S. in Engineering Science (1987) from Hudson Valley Community College, and an MBA (1993) from the State University of New York.

While completing studies for his Master's of Engineering degree, Mr. Bascom worked in the Software Products Department of Power Technologies, Inc. to develop time over-current and distance relay software for PSS/E. He joined PTI's Underground Cable Systems group in 1990 as an Analytical Engineer where he spent nine years gaining experience in the T&D Technology and System Planning & Operations departments wh ile focusing on underground and submarine cable applications and technologies. Mr.

Bascom was with Power Delivery Consultants from 1999 to 2010 where he continued specializing in the underground cable systems, providing support to utility and research projects, and coordinating all of PDC's short courses and educational accreditation with IACET and the Florida Board of Professional Engineers.

Mr. Bascom co-founded Electrical Consulting Engineers in 2010. As company President and Principal Engineer, he specializes in studies including the following areas:

Design, specification preparation, bid review, Magnetic field analysis and mitigation quality assurance field installation observer, and Ampacity audits for uprating cable circuits, support of commissioning of new underground including the use of distributed temperature transmission circuits, including hybrid overhead- sensing (DTS) equipment and techniques underground lines Costing studies and budgetary evaluations of Cable engineering design for horizontal underground cable altematives up to 500kV directional drilled projects, including feasibility Forced cooling, and slow and rapid circulation studies ana*lyses for pipe-type cables Factory testing witness and certification for new Research projects involving underground cables cable systems and factory acceptance tests During his career, Mr. Bascom has developed analytical methods used for the analys is and design of power equ ipment. Some of these methods were incorporated in tools such as cable ampacity softv..rare for Genera l Electric, pu lling-tension software for Con Edison of New York, and circu it breaker coordination , costing and fault softv..rare for a joint venture by Alcan and Square D. He has also developed some of ECE's in-house ana lytical tools for ampacity, pulling tension , magnetic field and forced cooling analyses.

Mr. Bascom has been involved in severa l research projects for the Electric Power Research Institute including development of the EPRIGEMS Cable Ampacity Tutorial, Altemative Cable Evaluation (ACE) program, Power Transformer Analysis (PTLOAD) system , authoring an expert system and reference manual for underground cable fault location, as Principal Investigator for the UTWorkstation and developer of the underground and aerial cable models in the Dynam ic Thermal Circuit Rating (DTCR) system . Mr. Bascom was a reviewer of the 1992 edition of EPRI's Underground Transmission Systems Reference Book and principal author of the ampacity chapter in the 2006 edition.

Mr. Bascom has instructed short courses for the University of Pennsylvan ia, Power Delivery Consultants, Siemens and Plerra Consulting involving cable system design, uprating, analytical techniques, and hybrid (underground and overhead) line design. He is a Senior Member of the IEEE, its Power & Energy Society and Standards Association, a voting member of the Insulated Conductors Committee (ICC), a member of CIGRE and the U.S. representative for Working Group B1.35, and a past member of the National Association of Corrosion Engineers (NACE). Mr. Bascom co-authored the cable systems chapter in the 14th and 15th editions of the McGraw-H ili Standard Handbook for Electrical Engineers and is active in severa l ICC working groups, has contributed to the development of IEEE guides and standards including being cha irman of ICC caw to develop a standard for AC cable systems above 161kV and was co-chairman of ICC WG 7-41 ,

Transmission Cable Operations Report. Mr. Bascom is a registered Professional Eng ineer in New York, Florida and Texas and the author of over 40 technical papers and publications. He holds 1 patent.

1. >>011 35 Report of Earle Bascom III

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1.0 INTRODUCTION

2.0 BACKGROUND

3.0 DESCRIPTION

6.0 CONCLUSION

7.0 REFERENCES

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