**\[DNFSB LETTERHEAD\]**

July l0, 2003

The Honorable Jessie Hill Roberson

Assistant Secretary for Environmental Management

U.S. Department of Energy

1000 Independence Avenue, SW

Washington, DC 20585-0113

Dear Ms. Roberson:

Enclosed for your consideration and action, as appropriate, are
observations developed by the members of the staff of the Defense
Nuclear Facilities Safety Board (Board) concerning the electrical and
lightning protection systems for the K-Area Material Storage (KAMS)
Facility, FB-Line, and Building 235-F at the Savannah River Site. This
review is part of an overall safety assessment undertaken in response to
Public Law 107-314, Section 3183, *Study of Facilities for Storage of
Plutonium and Plutonium Materials at Savannah River Site*.

The staff's review identified issues related to electrical and lightning
protection systems in each facility. Specifically, the issues concern
the capability of electrical equipment in KAMS to perform a safety
function, the adequacy of the lightning protection system and aging
electrical cables in Building 235-F, and the potential need for applying
ampacity derating factors to certain cables in FB-Line. The Board asks
to be informed of DOE's actions to address the issues discussed in the
enclosed report.

Sincerely,

***John T. Conway***

***Chairman***

c: Mr. Jeffrey M. Allison

Mr. Mark B. Whitaker, Jr.

Enclosure

**DEFENSE NUCLEAR FACILITIES SAFETY BOARD**

# Staff Issue Report

June 24, 2003

**MEMORANDUM FOR:** J. K. Fortenberry, Technical Director

**COPIES:** Board Members

**FROM:** A. K. Gwal

**SUBJECT:** Review of Electrical and Lightning Protection Systems for
K-Area Material Storage Facility, FB-Line, and Building 235-F at
Savannah River Site

In Public Law 107-314, Section 3183, Study of Facilities for Storage of
Plutonium and Plutonium Materials at Savannah River Site, Congress
tasked the Defense Nuclear Facilities Safety Board (Board) to conduct a
study of the adequacy of the K-Area Material Storage Facility (KAMS) and
related support facilities, such as Building 235-F (235-F), at the
Savannah River Site (SRS) for the storage of defense plutonium and
defense plutonium materials in connection with the Department of
Energy's (DOE) fissile materials disposition program. This report
documents a review by the Board's staff of the electrical and lightning
protection systems for KAMS, FB-Line, and Building 235-F at SRS
conducted as part of that overall study. This review was conducted by
staff members A. Gwal, B. Broderick, C. March, and T. Davis during May
6--8, 2003.

**KAMS.** The Board's staff made the following observations with respect
to KAMS.

*Electrical Distribution System*―In general, the staff found the
electrical distribution system to be adequate since the system is
currently not credited with any safety function.

However, in a letter dated June 12, 2003, the Board noted that the
ventilation system for KAMS was not designated as safety-class
consistent with DOE requirements to preclude unacceptable off-site
consequences during certain accidents. Such a designation would require
reclassification of the existing electrical system and significant
enhancements to the present emergency power capability.

*Electrical Calculations*―The short-circuit analysis for KAMS is based
on the short-circuit currents from the original electrical calculations
for K-Reactor. Because there have been major equipment modifications,
including removal of many of the electrical loads, the short-circuit
analysis needs to be reevaluated using short-circuit currents based on
the existing configuration of the electrical distribution system. Such
an evaluation would verify the capability of the electrical equipment to
perform safely without initiating a fire or an explosion.

**Building 235-F.** The staff's observations regarding Building 235-F
are detailed below.

*Lightning Protection System*―The current lightning protection system is
intended to provide protection via the partial Faraday cage that is
established by the building's interconnected structural steel rebar.
However, the existing arrangement is rendered ineffective by unbonded
metallic penetrations that breach the cage boundary. By attaching to an
unbonded rooftop or high-elevation penetration, lightning energy
(capable of igniting in-situ combustibles) could couple directly into
the facility, bypassing the rebar cage altogether. Given the lack of
viable fire suppression capabilities in 235-F, it would be prudent to
install a lightning protection system compliant with National Fire
Protection Association (NFPA) Standard 780, Standard for the
Installation of Lightning Protection System.

*National Electric Code (NEC)-Type Assessments*―The electrical
distribution system in 235-F was installed in accordance with the 1957
version of the NEC. Facility personnel were unaware of any assessments
performed in recent years to ensure compliance with either the current
NEC or the code of record. Such assessments are performed routinely for
the commercial nuclear industry by NEC-qualified inspectors and have
been performed for other facilities at SRS to evaluate electrical
systems for compliance with the NEC. The staff believes it would be
beneficial to assess the existing electrical system for 235-F against
current code requirements to identify potential fire hazards and
understand latent system vulnerabilities.

*Calibration of Protective Devices*―To ensure reliable operation,
Institute of Electrical and Electronics Engineers (IEEE) Standard
242-2001, *IEEE Recommended Practice for Protection and Coordination of
Industrial and Commercial Power Systems*, recommends that electrical
protective devices be maintained and calibrated in accordance with
manufacturer's recommendations. The 235-F circuit breakers and relays
are maintained on a 5-year calibration frequency. Representatives of
235-F could not verify whether this calibration frequency is consistent
with the manufacturer's recommendation. The Board's staff believes the
calibration tests on the breakers and relays should be in accordance
with the manufacturer's recommendation to ensure that the equipment will
operate as designed.

*Electrical Cables*―The majority of the electrical cables in 235-F are
approximately 50 years old and have exceeded their estimated design
life. Power, instrumentation, and control cables can deteriorate during
service. When cable jackets and insulating materials age, they become
brittle and may crack. Because a number of facility safety systems rely
on the working condition of these cables, continued monitoring of their
condition is an essential part of effective preventive maintenance. Such
monitoring of the condition of the cables improves the service life and
reliability of electrical equipment by detecting damaged and
deteriorating power and instrumentation and control cables prior to
equipment failure.

Several techniques for this type of monitoring exist; for example, the
Defense Waste Processing Facility at SRS uses an Electronic
Characterization and Diagnostics. (ECAD) system for monitoring the
condition of cables. The types of degradation and problems that can be
detected by the ECAD system are changes to dielectric materials,
deterioration of circuit insulation, high-resistance connections, short
circuits, open circuits, moisture intrusion, circuit noise, and
development of conducting paths. The condition of safety-related cables
needs to be determined using a suitable system for monitoring the
condition of the cables to support a long-term storage mission in this
building.

**FB-Line.** The staff made the following observations with regard to
FB-Line.

*Ampacity Derating of Fire-Protected Cables*―In one of the stairwells,
the power, instrumentation, and control cables routed through the cable
trays are coated with a protective material (Flammastik) to prevent the
initiation and rapid propagation of fire. Such protective coatings may
reduce the heat transfer characteristics associated with the ampacities
codified in industry standards. Hence, ampacity testing to determine
whether the coating has affected the rating of fire-protected cable
systems is necessary. The Board's staff believes IEEE Standard 848-1996,
*IEEE Standard Procedure for the Determination of the Ampacity Derating
of Fire-Protected Cables*, should be used to evaluate the adequacy of
the coated cables in the stairwell, as well as in other locations where
such coated cables exist.

*NEC-Type Assessments*―As discussed above for Building 235-F, it would
be beneficial to assess the existing electrical system against current
code requirements to identify potential fire hazards and understand
latent system vulnerabilities.