PREPARATION OF SAFETY

1
PREPARATION OF SAFETY ENVIRONMENTAL
DOCUMENTATION, AND THE APPROVAL PROCESS FOR TFTR
DT OPERATIONS

• Jerry D. Levine
• June 24, 2014

2
TFTR Environmental Reviews

• NEPA Reviews in 1975 (FES) and 1990-92 (EA).
• FES 1000 equivalent full power D-T pulses per
  year for 4 years, 3 x 1021 total neutrons
  produced, 4 person-rem/year within 50 miles, 5.9
  mrem/yr routine dose at the site boundary,
  routine release of 0.74 Ci/yr of tritium, worst
  case accident release of 1.3 kCi HTO.
• EA About 60 equivalent full power D-T pulses per
  year for 1-2 years, 1 x 1021 total neutrons
  produced, 17 person-rem/year within 50 miles, 8.3
  mrem/yr routine dose at the site boundary,
  routine release of 500 Ci/yr of tritium, worst
  case accident release of 25 kCi HTO.

3
TFTR Environmental Reviews

• Lengthy review and approval process for the EA.
• Series of non-concurrent reviews by several
  levels within the DOE organization (Princeton
  Area Office Chicago Operations Office Office of
  Fusion Energy Office of Energy Research Office
  of Nuclear Safety Office of General Counsel and
  Office of Environment, Safety Health).
• EA then reviewed by New Jersey Department of
  Environmental Protection (NJDEP) comments
  resolved prior to DOE approval.
• PPPL had two public meetings at the Laboratory to
  present the D-T Program and the results of the EA
  to interested members of the public.
• Finding of No Significant Impact (FONSI) by DOE
  in January 1992.

4
TFTR Environmental Reviews

• Several issues arose at the end of the EA/FONSI
  process
• Lack of sufficient inventory of large shipping
  containers for tritium lead to proposal to
  construct and operate a Tritium Purification
  System to recycle tritium and reduce number of
  annual shipments by factor of 10.
• Underestimate of tritium retention rate in torus
  vacuum vessel ( maximum releasable tritium from
  the torus) by factor of 2.
• Supplemental Analysis (SA) to EA was prepared
  (beginning Feb. 1992) to address document these
  issues.
• SA reviewed by several DOE organizations starting
  July92. In January 1993, DOE concluded that
  based on the SA, the proposed changes to the TFTR
  D-T Program required no additional review under
  NEPA.

5
TFTR Safety Review and Approval

• PSAR reviewed/approved by DOE in 1978 for
  authorization of substantial TFTR construction
  (i.e., pouring of concrete for the Test Cell
  which housed the tokamak). 1000 pages modeled on
  USNRC requirements for commercial nuclear power
  plants. One year to prepare.
• Worst case accident" identified
  (non-mechanistically) as "massive destruction of
  the Test Cell" when the torus, neutral beams, and
  the tritium injection assemblies around the torus
  have their maximum tritium inventories. Maximum
  offsite dose (at site boundary, 125 meters from
  torus centerline) is 2.73 rem, lt 5 rem design
  objective.
• gt300 (DOE) comments, 5 months to review/approve.

6
TFTR Safety Review and Approval

• FSAR approved by DOE to support initial ("first
  plasma") TFTR operations in December 1982,
  following a three year preparation and review
  effort. Same size and format as PSAR.
• Upgraded system descriptions, and refined
  potential accident scenarios and their
  consequences.
• Using data from small onsite meteorological
  tower, maximum offsite dose due to "worst case
  accident" (the same accident included in the
  PSAR) was calculated to be 660 mrem.
• 300 DOE comments, but individual DOE
  organizations sent comments as they were
  generated, expediting the review and approval
  process.

7
TFTR Safety Review and ApprovalD-T Authorization
Basis

• Collection of documents that constituted the
  agreements between DOE and PPPL for safely
  operating the TFTR nuclear facility was known
  as the Authorization Basis, which was the basis
  for approval to run the D-T Program.
• The TFTR D-T Program Authorization Basis
  included
• Hazard Classification Category 3 nuclear
  facility, potential for only local consequences.
  Based on 50 kCi tritium inventory limit.
• Updated FSAR Started in 1990, 3 years to
  complete, gt400 comments to resolve. Worst case
  accident pipe break causing air ingress to the
  tritium storage beds, pyrophoric reaction between
  the air and the uranium tritide causing 25 kCi
  HTO to be released to the environment via the
  stack, resulting in an offsite dose of 140 mrem.
• EA, FONSI, and SA Includes "worst case beyond
  design basis accident same as updated FSAR but
  with failure of stack fans causing ground level
  release of 25 kCi offsite dose of 390 mrem.

8
TFTR Safety Review and ApprovalD-T Authorization
Basis

• Authorization Basis (continued)
• Technical Safety Requirements (TSRs) Conditions,
  safe boundaries, and management or administrative
  controls necessary to ensure the safe operation
  of a nuclear facility. For TFTR, these were no
  more than 50 kCi of tritium onsite, and no more
  than 25 kCi in any system or component from which
  it could be released as a result of a credible
  accident analyzed in the FSAR.
• DOE Safety Evaluation Report (SER) The
  DOE-prepared Safety Evaluation Report (SER) to
  document their review of the updated FSAR, and
  the reasons for their acceptance of his document.
• Unreviewed Safety Question Determinations
  (USQDs) USQDs are performed to determine if
  proposed facility physical or operational
  changes, or new information regarding previous
  safety analyses, impacts the DOE approved
  Authorization Basis. gt400 USQDs were done for
  TFTR without uncovering a USQ.

9
Radiological Releases Offsite Doses During
TFTR D-T Program and DD (1994-2002)

• Annual airborne releases of tritium (via stack)
  range of 62-260 Ci/yr, average was 131 Ci/yr.
  Limit was 500 Ci/yr.
• Annual airborne releases of short-lived
  activated air products (Ar-41, N-13, N-16, Cl-40,
  S-37) range of 10-31 Ci/yr, average was 21 Ci/yr
  (during D-T experiments, 1994-97).
• Annual liquid tritium releases (to sanitary sewer
  system via TFTR Liquid Effluent Collection
  Tanks) range of 0.071-0.951 Ci/yr, average was
  0.322 Ci/yr. Limit was 1 Ci/yr.
• Maximum Annual Individual Effective Dose
  Equivalent (at Site Boundary) range of 0.21-0.68
  mrem/yr, average was 0.40 mrem/yr. Limit was 10
  mrem/yr.

10
Site Specific Climatology Study

• Projections of offsite consequences from airborne
  radiological releases can be very sensitive to
  atmospheric conditions in the vicinity of the
  release point. This is particularly important
  for a small site like PPPL which contains a
  number of large buildings surrounded by trees.
  Use of standard Gaussian diffusion models
  significantly overestimate offsite dose.
• In July-Sept 1988, NOAA conducted a field
  measurement program to directly evaluate
  atmospheric diffusion conditions in the vicinity
  of PPPL. Four (4) tracer gas release points
  (exhaust stack 3 ground level release points)
  were chosen to simulate potential pathways for
  release of effluents from the TFTR Facility. 98
  receptors collected data within 1 km of TFTR.
• Results were data set of source strength
  normalized concentrations (X/Qs). These proved
  that maximum projected offsite dose from the
  worst case accident would be a factor of 16 less
  than that calculated using the standard models.

11
Radiation Shielding Evaluation

• Original design of the TFTR radiation shield
  system envisioned a peripheral igloo shield
  surrounding the tokamak device for D-T
  experiments. Caused much concern about machine
  access needs.
• Through additional detailed analyses, radiation
  measurements during the extensive TFTR D-D
  experimental program (1983-93), and simulations
  using a neutron source, it was determined that
  the igloo shield was not required.
• Some supplemental concrete shielding was added at
  the Test Cell walls.
• Projected contribution to annual site boundary
  dose from neutron/gamma radiation during TFTR D-T
  experiments with as-built shielding was 1.6
  mrem/yr. Actual contribution was 0.027-0.078
  mrem/yr (0.05 mrem/yr avg).

12
Control of Operating Parameters for Safe D-T
Operations

• PPPL believed it prudent to establish a number of
  operating parameter requirements (OPRs) for D-T
  operations to ensure that the engineered
  detection and mitigation systems would be
  operating or operable when required.
• OPRs were established for area, stack and
  glovebox tritium monitors room pressure
  differentials minimum exhaust stack flow and
  stack negative pressure fire detection and
  suppression systems tritium cleanup systems
  standby power system tritium systems controls
  meteorological tower instrumentation torus and
  neutral beam vacuum alarms interlocks for
  control of tritium gas transfers to injection
  volumes in the Test Cell pressure, temperature
  and atmospheric constituents of tritium glove
  boxes and waste handling fume hood Tritium
  Purification System radiation monitors at the
  TFTR facility boundary and tritium material
  control and accountability equipment.

13
Control of Operating Parameters for Safe D-T
Operations

• OPRs typically required operation or operability
  of these systems and components, or a particular
  range of parametrics, in order to enter a mode in
  which tritium transfer operations (TTOs) were
  allowed, to initiate specific TTOs, or to
  continue to conduct specific TTOs.
• If a particular OPR condition wasnt satisfied
  (e.g., a tritium monitor was inoperable or in
  alarm), actions to restore the condition (or, in
  some cases, to provide an approved substitute)
  must take place within a specified time interval
  before the relevant TTO must cease and/or actions
  to mitigate a potential problem must occur (e.g.,
  initiate cleanup processing of a glove box).
• Surveillance intervals for systems, components
  and parametrics were specified to ensure that
  OPRs were maintained. Failure to perform a
  surveillance requirement within 125 of the
  specified time interval constituted failure to
  satisfy the OPR.