TRANSMITTED TO DOE/M. WHITAKER 5/15/95

DEFENSE NUCLEAR FACILITIES SAFETY BOARD

November 23, 1994

MEMORANDUM FOR:          G. W. Cunningham, Technical Director

COPIES:             Board Members

FROM:                    C. H. Keilers, Jr.

SUBJECT:            Hanford - Review of Preparations to Install K-Basin
                    Chute Barriers

1.   Purpose:  This report documents a review of preparations to install
     isolation barriers in the Hanford K-Basins and thereby resolve an
     Unreviewed Safety Question (USQ).  This review was performed by D. Grover,
     P. Gubanc, C. Keilers, and D. Winters of the Defense Nuclear Facilities
     Safety Board (Board) technical staff on November 14-16, 1994.

2.   Summary:  Installation of the isolation barriers represents significant
     progress in mitigating the basin seismic vulnerabilities and improving
     their safety.  A Westinghouse Independent Design Review Committee reviewed
     the barrier design.  Contingent on satisfactory resolution of their
     comments, the staff believes the barriers will perform as intended. 
     However, the potential for subcontractor operations to effect the safe and
     timely installation of the barriers needs more attention.  In particular,
     the critical lift procedure should be thoroughly reviewed, and rigging
     personnel qualifications should be evaluated.  Detailed comments on
     rigging and handling are provided in the Attachment.

3.   Background:  The K-Basins are separated from their reactor buildings by
     unreinforced joints in the basin chute.  These joints have leaked before
     and were repaired with epoxy.  Furthermore, an earthquake could produce
     relative motion across the joints, causing a higher leak rate than that
     evaluated in the safety analysis report (SAR).

     To resolve this condition, Westinghouse Hanford Company (WHC) plans to
     install barriers that will isolate spent fuel and sludge from the
     potentially leaky chutes.  Before installation, WHC will remove several
     nearby loaded canisters in the K-West basin and several empty canisters in
     the K-East basin.  A subcontractor (Sonsub, Inc.) will then cut away
     nearby fuel racks, prepare the chute opening, and mount a new sealing
     surface.  Next, Kaiser Hanford Company will bring each barrier into the
     facility, rig it into position, and secure it in place.  After
     installation, WHC will confirm by test that the leak rate past the
     barriers is less than half the SAR limit.

4.   Discussion:  The Board staff reviewed preparations for K-Basin barrier
     installation, including observing the WHC Readiness Assessment for the
     installation and discussing comments made on the barriers by the WHC
     Independent Design Review Committee.  The staff considers that the overall
     conduct of the WHC Readiness Assessment was satisfactory.  However, the
     scope of the assessment was limited and did not include the procedures and
     personnel qualifications of the subcontractors (Kaiser and Sonsub).  In
     particular, the Kaiser critical lift procedure was not evaluated.

     Inadvertently dropping a barrier (2700 lbs.) could damage the attached
     rubber seal and significantly delay installation.  Dropping a barrier
     could also damage fuel canisters or the existing epoxy joint repair in the
     chute, resulting in basin leakage.  The Kaiser critical lift procedure is
     key to ensuring safe installation of the barriers.  However, this
     procedure does not fully comply with the Department of Energy (DOE)
     approved Hanford site rigging manual and cannot be performed exactly as
     written.  The technical basis for the procedure is also not apparent due
     to a lack of load calculations for the rigging equipment.  The attachment
     contains more observations on this procedure.
  
     Satisfactory resolution of comments from the Independent Design Review
     Committee is key to ensuring that the barriers will function as intended. 
     In particular, the seismic adequacy of the island following an aftershock
     that drains the chute needs to be understood.  Resolution of the
     Committee's comments appears to lack sufficient facility management
     priority and may warrant a pre-start finding.  The Board staff is still
     following the resolution of these comments and believes the barriers will
     perform as intended, contingent on satisfactory resolution.

5.   Future Planned Activities:  The Board staff will continue to follow the
          barrier installation.     Board Staff Comments on Isolation Barrier Critical Lift Procedure

1.   Requirements:  The DOE approved site rigging manual states that a manager
     may authorize an item be handled as a critical lift when dropping, upset,
     or collision could cause costly damage, unacceptable delays, release of
     radioactivity, etc.  According to the rigging manual:

     a.   The manager shall designate a Person In Charge