Peter S. \Vinokur, Chain11an

Jessie H. Roberson, Vice Chain11an

John E. Mansfield

] oseph F. Bader

Sean Sullivan

Mr. Kevin W. Smith

Manager, Los Alamos Site Office

U.S. Department of Energy

747 West Jemez Road

TA-3 Building 1410, Mail Stop-A316

Los Alamos, New Mexico 87544

Dear Mr. Smith:

FACILITIES

\Vashington, DC 20004-2901

November 19,2012

The Defense Nuclear Facilities Safety Board (Board) has reviewed the approved safety basis

for Area G at Los Alamos National Laboratory (LANL). This review revealed multiple

inconsistencies between the hazard and accident analyses and the objectives outlined in Department

of Energy Standard 3009-94, Change Notice 3, Preparation Guide for u.s. Department of.Energy

Nonreactor Nuclear Facility Docun1ented Safety Analyses. These inconsistencies include:

• A non-conservative damage ratio that is not technically justified or based on a formally

credited safety control

• Exclusion ofsealed sources from the quantity of material-at-risk with no analysis to show

that they would survive design basis accident conditions

• An unanalyzed hazard in the safety basis involving a forklift puncturing a propane tank

The Board believes the above inconsistencies and deficiencies result in a significant

underestimation of the potential radiological dose consequence to the public and, consequently, an

inadequate control set to protect the public. Further, the Board believes that the overall safety

posture of Area G could be improved if other observations noted in the enclosed report are addressed

in the next annual update of the safety basiso Therefore, pursuant to 42 DoS.Co § 2286b(d), the Board

requests a report within 60 days of the receipt of this letter describing plans to address the issues

noted above and in the enclosed report.

Peter S. Winokur, Ph.D.

Chairman

Enclosure

c: Mrs.. Mari-Io Campagnone
DEFENSE NUCLEAR FACILITIES SAFETY BOARD

StaffIssue Report

September 25, 2012

MEMORANDUM FOR:

COPIES:

FROM:

SUBJECT:

T. J. Dwyer, Technical Director

Board Members

M. Dunlevy

Basis for Interim Operation, Area G, Los Alamos National

Laboratory

This report documents a review conducted by the staff of the Defense Nuclear Facilities

Safety Board (Board) during June 19-21,2012, of the Basis for Interim Operation (BIO) at Los

Alamos National Laboratory's (LANL) Area G. The staff met with personnel from Los Alamos

National Security, LLC (LANS) and the National Nuclear Security Administration's (NNSA)

Los Alamos Site Office (LASO) to discuss the details of the updated BIO for Area G. The staff

also conducted walkdowns of Area G facilities and observed workers opening and processing the

contents of a standard waste box. Following the onsite portion of the review, the staff requested

and reviewed documents in July, August, and September. Staff members participating in this

review included B. Broderick, T. Davis, M. Dunlevy, W. Futrell, C. Johnson, J. Pasko, and B.

Sharpless.

Background. During March 2012, the LASO manager approved the first major update

to the Area G safety basis since April 2003. Currently, Area G is scheduled for closure by 2015

(Order of Consent, 2005) and therefore qualifies as a limited-life facility consistent with

Department of Energy (DOE) Standard 3011-02, Guidance for Preparation ofBasis for Interim

Operation (BIO) Documentso As a result, only a BIO (rather than a Documented Safety Analysis

[DSA]) is required to meet safe harbor expectations consistent with Title 10 of the Code of

Federal Regulations, Part 830, Nuclear Safety Management. However, according to DOE

Standard 3011-02, Chapters 2-6 of the BIO should still be compliant with DOE Standard 3009-

94, Change Notice 3, Preparation Guide for UoSo Department ofEnergy Nonreactor Nuclear

Facility Documented Safety Analyses (DOE Standard 3009)0

Hazard and Accident Analyses. The Board's staffreviewed the Area G BIO and noted

the following concerns regarding the hazard and accident analyseso

Damage Ratio-LANS safety analysts use a damage ratio of 0.01 in the Area G BIO

when calculating the release of tritium in waste containers via a fire without justifying that

assumption or crediting the containers as a safety controlo This approach is inconsistent with

DOE Standard 3009, which states, "Exclusion of MAR [material-at-risk] from the source term

may be based on qualified containers (which may then be designated as SC [safety-class] design
features), consideration regarding the specifics of the accident scenario through the definition of

the damage ratio or other appropriate means." Accordingly, LANS personnel should either

technically justify a damage ratio less than 1.0 or formally credit the container as a safety

control.

Sealed Sources-LANS safety analysts assign a damage ratio of zero to sealed

radioactive sources that are certified as American National Standards Institute (ANSI)

N.43.6/ISO 2919 Class 4 for temperature performance (the container is rated to survive a fire not

exceeding a temperature of 400°C and lasting 1 hour)--thereby excluding these sources from the

MAR in the Area G BIO. However, the BIG does not analyze whether a temperature exceeding

400°C is credible under accident conditions. This approach is inconsistent with DOE Standard

3009, which states, "While [DOE Standard 1027] excludes material in qualified containers

[containers that comply with ANSI N.43.6] from consideration for the purposes of hazard

classification, the existence of such material should be acknowledged in a DSA. Such material

should later be excluded from the source term for the applicable accident scenarios if the

containers can be shown to perform their functions under the accident environments."

Accordingly, LANS personnel should either include sealed sources in the quantity of MAR

analyzed in the safety basis or technically justify excluding them.

Unanalyzed Hazards-The Area G BIG does not analyze the puncture of a propane tank

or damage to the fuel line on a forklift whereby the escaping gas immediately ignites, resulting in

a "blowtorch" effect. This postulated accident could impact both the facility workers and the

MAR. This event is credible whenever a forklift is operating within a facility, and it becomes

more likely when multiple forklifts are operating simultaneously in the same facility.

Particulate Deposition Velocity-DOE's Office of Health, Safety and Security issued

Safety Bulletin 2011-02, AccidentAnalysis Parameter Update, which concludes that a dry

deposition velocity value of 1 cm/s for unfiltered/unmitigated releases may not be reasonably

conservative for all DOE sites and accident scenarios. As a result, the Safety Bulletin

recommends using a default value of 0.1 cm/s or technically justifying the use of a site-specific

value. LANS safety analysts use a dry deposition velocity value of 1 cm/s for particulates in the

Area G BIG. However, a recent report (Napier, 2011) states, "For calculations at distances of

less than about 2 miles [at LANL], deposition velocities as low as 0.002 m/s (0.2 cm/s) for both

particles and reactive gases could be appropriate." The distance between facilities at Area G and

the maximally exposed offsite individual is less than 2 miles. A lower deposition velocity

reduces the calculated plume depletion, resulting in a higher predicted dose consequence to the

public.

LANS safety analysts justify using this non-conservative deposition velocity in

SBTSWP-12-001, Rev. 0, Justification ofthe Use of1 cm/s Deposition Velocity inMACCS2 for

LANL Applications. This document states, "The results show that the non-conservative use of a

1 em/sec DV [deposition velocity] value is offset by over-conservatism in the MACCS2

dispersion coefficients." The Board's staffbelieves safety basis analysts should always use

technically justified values for all input parameters in the radiological dose consequence,

consistent with DOE Standard 3009.

2
Tritium Oxide Deposition Velocity-LANS safety analysts use a dry deposition velocity

value of 0.5 cm/s for tritium oxide in the Area G BIO, citing the MACCS2 Computer Code

Application Guidance for Documented Safety Analysis Final Report (MACCS2 Application

Guidance) (U.S. Department of Energy, 2004) as the basis. Research has shown that this value is

neither conservative nor appropriate for the time scale of most design basis accidents (see the

Board's August 19, 2011, letter to the NNSA Administrator). Further, it should be noted that the

use of any non-zero dry deposition velocity value for tritium oxide is valid only if reemission

(the release of tritium from vegetation and soil back into the atmosphere) is adequately

accounted for. Reemission is rapid, and at least one study has shown that more than 50 percent

of deposited tritium oxide can be reemitted during a 12-hour period (Taschner et al., 1997).

As a point of reference, safety analysts at the Tritium Facility at Lawrence Livermore

National Laboratory use a dry deposition velocity value of 0.0 or 0.1 cm/s for tritium oxide in

their accident analysis calculations. Further, Savannah River National Laboratory issued a report

(Murphy et al., 2012) stating that, "an effective deposition velocity [for tritium oxide] of 0.0

cm/s is appropriate for safety analysis with the MACCS2 code" for the Savannah River Site.

Although the specific conditions that affect the deposition velocity of tritium oxide may differ

from site to site, the overall conclusion remains the same: the value recommended in the

MACCS2 Application Guidance is not conservative.

Fire Protection. The Board's staff noted the following concerns during its review of the

Area G facilities and associated fire protection program.

Fire Suppression-The fire suppression system for Dome 229, a hazard category 2

nuclear facility, has been shut down (impaired) and is no longer maintained. Although the fire

suppression system is not a credited safety feature in the Area G BIO, DOE Order 420.1B,

Facility Safety, requires that automatic fire suppression systems be provided in all significant

facilities, including hazard category 2 nuclear facilities. LANL fire protection personnel

recognized this deficiency and submitted an exemption request in September 2011 for Dome 229

and five other domes housing hazard category 2 quantities of MAR. NNSA has not yet acted

upon this request. The Board's staff believes the delay in taking corrective action contributes to

a degraded safety posture at Area G.

Dome 231 & Dome 375 Fire Suppression-At the time ofthe staff's visit, LANL was

investigating the feasibility of installing a foam fire extinguishing system inside enclosures being

erected in Domes 231 and 375 to support wooden waste box disposition efforts. LANL fire

protection personnel have subsequently informed the staff that they will instead install a preaction automatic sprinkler system in each enclosure. This action will provide fire suppression

capabilities, as required by DOE Order 420.1B, within the enclosures.

Wildland Fire Control Observation-Currently, little mitigation effort has been

undertaken to reduce the fuel (grasses, brush, and dead trees) for wildland fires along the primary

access road, which firefighting vehicles would use to respond to and defend Area G against a

wildland fire. Given the Los Alamos region's susceptibility to wildland fires, the staffbelieves

that fuel mitigation and reduction activities along the primary access road and in Area G should

3
be given appropriately high priority to ensure that emergency responders can affect a timely

response to protect the large quantity of above ground transuranic wastes at Area G.

Accordingly, LANS management is considering fuel mitigation activity along the primary Area

G access roadway during 2013 and the relocation of some personnel and removal of some

combustible trailers that are located along the roadway.

4
References

Murphy, C., P. Lee, B. Viner, and C. Hunter, 2012, Recommended Tritium Oxide Deposition

Velocity for Use in Savannah River Site Safety Analyses, SRNL-STI-2012-00128, Rev. 0,

Aiken, SC: Savannah River National Laboratory.

Napier, B. 2011, Dry Deposition Velocity Estimation for the Los Alamos Site,

PNNL-20440, Battelle, Pacific Northwest National Laboratory.

Taschner, M., C. Bunnerberg, and W. Raskob, 1997, "Measurements and Modeling of

Tritium Reemission Rates after HTO Depositions at Sunrise and at Sunset," Journal of

Environmental Radioactivity, 32, pp. 219-235.

State of New Mexico Environment Department, March 1, 2005, Compliance Order on

Consent

u.s. Department of Energy, 2004, MACiCS2 Computer Code Application Guidance for

Documented Safety Analysis Final Report, DOE-EH-4.2.1.4-MACCS2-Code Guidance,

Washington, DC.

5