ML20213F156
| ML20213F156 | |
| Person / Time | |
|---|---|
| Site: | Turkey Point  |
| Issue date: | 11/05/1986 |
| From: | Stello V NRC OFFICE OF THE EXECUTIVE DIRECTOR FOR OPERATIONS (EDO) |
| To: | Chiles L SENATE |
| Shared Package | |
| ML20213F158 | List: |
| References | |
| REF-GTECI-A-49, REF-GTECI-RV, TASK-A-49, TASK-OR NUDOCS 8611140037 | |
| Download: ML20213F156 (25) | |
Text
.. _ - . .____- .. . _ . - - _ ..
en ung%,, UNITED STATES 3 -[$ y,
- j NUCLEAR REGULATORY COMMISSION WASHINGTON, D. C. 20655 g
- % , ,
- NOV 0 51986 -
C The Honorable Lawton Chiles United States Senator Federal Building Lakeland, Florida 33801
Dear Senator Chiles:
- I am pleased to respond to your October 7,1986, letter. You indicated that a constituent of yours, Mr. Steve Conger, has expressed concern relating to an article by Ps. Joette Lorion of the Center For Nuclear Responsibility. The article is entitled "The '0-Welds' of Turkey Point " You further requested
% an update of recent actions taken at the Turkey Point Nuclear Power Plant in relation to operation and safety.
Before I respond to the contentions raised in the article and the actions taken
, to assure safe operation at the Turkey Point Plant, the following should be noted. The contentions expressed in the article are related to Ms. Lorion's concern of reactor vessel embrittlement (pressurized themal shock) at the Turkey Point Power Plant. The controlling (most embrittled) material for the Turkey Point Units 3 and 4 reactor vessels are the center girth welds.
- . Ms. Lorion refers to these welds as "0-Welds." Ms. Lorion has made these same arguments expressed in the article before the United States Court of Appeals for the District of Columbia Circuit. Enclosure 1 is our response to Ms.
Lorion's petition for which oral arguments were presented before the court on December 16, 1985. Er. closure 2 is the court's decision which ruled in favor of the Nuclear Regulatory Comission (NRC).
In relation to Ms. Lorion's contentions, the surveillance program for Turkey
- Point Units 3 and 4 comprises a set of capsules in each reactor containing i samples of the weld materials and base metals used in fabricating the beltline c' of the reactor vessel. During construction the capsules are placed in the _
vessel near the wall where they receive neutron radiation representative of -
that received by the beltline. In accordance with regulations, the first capsule is withdrawn after several years of operation when its contents have been exposed to neutron radiation at vessel operating temperature and the specimens are then tested to determine the change in resistance to brittle fracture caused by the radiation. Subsequent capsule withdrawals are scheduled l at specified intervals to monitor long-term effects throughout the reactor l vessel (s) lifetime.
As previously stated, the controlling (most embrittled) material for Turkey Point Units 3 and 4 reactor vessels are the center girth welds which are positioned at about midheight of the cores. Fabrication records show that the two welds were made with the same materials, that is, the same geld wire heat and the same flux lot. The surveillance welds made for Unit 3 test specimens were made with the same materials as the center girth welds in both reactor vessels. The surveillance welds for Unit 4 test specimens were ,
made with the same weld wire heat but different flux lot than the center girth l Welds in both reactor vessels. Although the Unit 4 surveillance weld specimens l were fabricated using a different flux lot, the weld specimens are considered l mWMM x t\ , c v.
1
. The Honorable Lawton Chiles i to be representative of the girth welds in both reactor vesselsebecause flux lot is considered to be of secondary importance in determining sensitivity I to radiation damage. Based on the similarity between materials in the center l girth welds and the materials used to fabricate the surveillance weld specimens, l' the test results from capsules in either Unit 3 or 4 can be used to monitor the neutron radiation damage to both reactor vessels.
l In 1985 the utility requested, and the NRC agreed to, an integrated surveillance '
program for Units 3 and 4. In each vessel there are two capsules containing the critical weld metal, and under the integrated program the test results from the four capsules will be applied to vessel integrity analyses for both units. '
Section II.C of 10 CFR 50, Appendix H permits an integrated surveillance program for reactors at the same or different physical sites if they meet the following specified criteria:
. 1. There must be substantial advantages to be gained, such as reduced power outages or reduced personnel exposure to radiation, as a direct result of not requiring surveillance capsules in all reactors in the set.
- 2. The design and operating features of the reactors in the set nust be sufficiently similar to permit accurate comparisons of the predicted 1
amount of radiation damage as a function of total power output.
l j 3. There must be an adequate dosimetry program for each reactor.
- 4. There must be a contingency plan to assure that the surveillance progran for each reactor will not be jeopardized by operation at reduced power l 1evel or by an extended outage of another reactor from which data are expected.
l
. 5. No reduction in the requirements for number of materials to be irradiated, specimen type, or number of specimens per reactor is permitted, but the
- * . . . . amount of testing may be reduced if the initial results agree with predictions. ~
- 6. There must be adequate arrangement for data sharing between plants.
An April 22, 1985, letter, which issued the amendments approving the integrated surveillance program, included a Safety Evaluation which identified the above criteria which must be met and an evaluation of how FPL met the criteria.
Ms. Lorion questions the applicability of surveillance test results from Unit 3 to analyses of Unit 4, and has quoted Dr. George Sih of Lehigh University to support her contention that this is " scientifically invalid." This contention is contrary to the basic assumptions behind the nuclear power industry and NRC use of radiation damage trend curves (e.g., Regulatory Guide 1.99) derived from analysis of data from many reactors. It is also contrary to NRC criteria for an integrated surveillance program (e.g., Appendix H, 10 CFR 50). Professor Sih's views were considered as part of the pressurized thermal shock studies in l the 1981-82 time period and were rejected due to lack of technical basis, i
The Honorable Lawton Chiles Based on the previously cited court decision and the technical basis in support of the integrated surveillance program for Turkey Point Units 3 and 4, Ms. Lorion's contentions have no merit. It also appears that Ms. Lorion believes that the only source of information about the neutron embrittlement of the materials in a given reactor vessel comes from the test results for specimens irradiated in that vessel as part of its surveillance program. I must emphasize that there is a sound basis for estimates of neutron embrittlement besides the information cbtained from plant specific surveillance.
Until plants have credible surveillance data of their own (preferably from two or more capsules) their submittals for pressure-temperature limits, which take '
account of radiation embrittlement, are based on knowledge of the chemical composition and the neutron fluence. Test data from many sources is used which has been characterized according to the critical variables, chemical compositio'n of the material and neutron fluence. On this basis, pressure-temperature limits
.have been established for Turkey Point Units 3 and 4 that ensure safe operation; and the susceptibility to the pressurized thermal shock has been evaluated.
The NRC has accepted certain fomulas for calculating the degree of embrittlement.
The basis for these fomulas is the rapidly growing surveillance data base from all power reactors. A significant margin is added to the calculated result to account for uncertainties. The NRC has established in 10 CFR 50.61 a screening criterion and identified acceptable means for calculating the reference tempera-ture to judge the condition of reactor vessels at all sites. A PTS screening criterion of 300*F has been established for circumferential (girth) weld
- material. As previously stated, the center girth welds are the most critical l
welds for PTS concerns at the Turkey Point site. The Turkey Point reactor vessels critical welds will remain below the screening criterion for their licensed life which assures continued safe operation of the Turkey Point Units.
- In sumary, there certainly is a need for care in monitoring the integrity of reactor vessels in all operating nuclear power plants. The nuclear power
- 4. industry and the NRC have expended considerable effort to ensure that safety margins are maintained by assuring that the extent of neutron radiation dama~ge is known. Contrary to Ms. Lorion's opinion, Turkey Point Units 3 and 4 are not operating in violation of NRC safety margins and their integrated reactor vessel material surveillance program conforms to NRC regulations and assures the best use of the available surveillance capsules containing the critical weld material for both units.
The NRC has an extensive inspection and enforcement program to assure that construction, operation and safety standards are met at all nuclear power plant sites. The Turkey Point Plant has two full-time resident inspectors onsite. In addition, several announced and unannounced inspections are perfomed by specialists from NRC Headquarters and the Region to augment the l resident inspection activities. The NRC has expended approximately-3,800 inspector hours at the Turkey Point site for the current calendar year.
l l
,. The Honorable Lawton Chiles The purpose of the NRC inspection and enforcement program is to promote and protect the radiological health and safety of the public by ensuring compliance with NRC requirements, obtaining prompt corrective actions, deterring future violations, and encouraging improvement in licensee performance. Prompt and vigorous enforcement action is taken when licensees do not achieve the necessary attention to detail and the high standard of compliance which the NRC expects.
Any licensee who cannot achieve these high standards will not be permitted to conduct licensed activities.
The NRC staff has completed approximately 48 licensing actions relating to the Turkey Point Plant Units 3 and 4 during this calendar year. Each licensing
- . action is supported by a detailed safety evaluation and results in operational changes, plant modifications or other actions resulting in an overall enhancement of plant safety.
Finally, I would like to note that Florida Power and Light Company (FPL) has developed a Performance Enhancement Program (PEP). The PEP focuses management
' attention on the Turkey Point Plant facilities, operation and maintenance.
FPL has devoted considerable resources to this program for enhancing the overall safe operation of the Turkey Point Plant.
In summary, I trust you find this responsive to your request and of assistance in assuring yourself and your constituents that the Commission actions in
- providing protection for all reactor vessels in operating nuclear power plants, including Turkey Point Units 3 and 4, are based on sound technical judgement.
The criteria which are used as the bases for approving integrated surveillance programs for various utilities, including FPL, are based on sound technical judgement.
l In addition, the ongoing activities related to inspection, enforcement and L
licensing at the Turkey Point Plant assure continued safe operation. The
- actions taken by the staff in these areas are consistent with the Commission's policy of ensuring all operating facilities achieve and maintain adequate fL leyels of protection of public health and safety. .
If. we can be of further assistance, please do not hesitate to contact us.
Sincerely, hicinal signed by Nictor Stello Victor Stello, Jr.
Executive Director for Operations
Enclosure:
- 1. Response to J. Lorien DISTRIBUTION: SEE NEXT PAGE l' Petition
- 2. U.S. Court of Appeal
- I Decision 'c h l
- See previous concurrence
- LA: PAD #2 *PM: PAD #2 *D: PAD #2 *AD:DPLA D R D: . EDO DMiller DMcDopald:he LRubepstein TNovak mer HD on VStello 10//g/86 10/F//86 10/,tW86 10/)7/86 Og /86 10/ /86 10/ /86
. go ,250/.23 /
- . DISTRIBUTION t, DecRet File w/cy of incoming NRC PDR w/cy of incoming Local PDR w/cy of incoming -
EDO #2208 c EDO Reading H. Denton/R. Vollmer J. Taylor C. Rossi PADf2 Rdg OGC-Bethesda SECY(3)
Y. STello PPAS (EDO #2208) D. Mossburg w/cy of incoming T. Novak/P. Baker L. Rubenstein It[/J "a d w/cy of incoming 0.' Mt tep 8A4 Mw
~
~
W ww u f~s~rt 4' v A>
d cA ut.
m
/
- m. .
?% . . .
l l
.c
ENCLOSURE 1 P. . . CASE SCHEDULED FOR ORAL ARGUMENT ON DECEMBER 16, 1985 IN THE UNITED STATES COURT OF APPEALS _
FOR THE DISTRICT OF COLUMBIA CIRCUIT
)
JOETTE LORION, ..'
)
d/b/a CENTER FOR NUCLEAR )
RESPONSIBILITY, -
)
. . :)
Petitioner, )
)
- v. )
)'
UNITED STATES NUCLEAR REGULATORY ) No. 82-1132 COMMISSION and the UNITED STATES )
OF AMERICA )
)
Respondents, )
)
and )
)
FLORIDA POWER & LIGHT COMPANY, )
. )
Interve'nor. )
)
RESPONDENTS' RESPONSE TO PETITIONER'S REPLY TO SUPPLEMENTAL BRIEFS OF RESPONDENT AND INTERVENOR l -
l 71. In this action petitioner Joette Lorion contests the
' 4~
.. . . 1981 NRC denial of her request, based on her concerns about -
radiation-induced embrittlement of the reactor pressure vessel, to consider suspending the operating license for the Turkey Point, Unit 4 nuclear reactor. Ms. Lorion in her October 18, 1985 " Reply to Supplemental Briefs of Respondent and Intervenor" (" Petitioner's Reply") asserts that the Turkey l Point, Unit 4 reactor vessel was more embrittled in 1981 than permitted by the Nuclear Regulatory Commission's ("NRC" or l " Commission") recently promulgated rule on pressurized thermal I
de e m - . . _ , - - - , - - -r .c, , . - - - , - -
6, d shock (" PTS"). To support this claim Ms. Lo ion cites a 1976 study, which was based on destructive tests (Cha,rpy tests) of material taken from capsules in Unit 4. Ms. Lorion projects from the data in that study, which was not specifically addressed in the NRC's denial of her request, that by 1981 the reference temperature, or R NDT, I for the reactor vessel for Unit 4 had exceeded the Commission's current screening criterion of 300'F for' protection against PTS. Petitioner's
\ Reply at 11-14. Ms. Lorion also clai'ms that the NRC has avoided this conclusion though the " legal alchemy" of using data from tests on capsules from Unit 3 rather than from Unit 4. Id. at 14-15.
Ms. Lorion's last-minute attempt to create an entirely new attack on the Commission's denial of her 2.206 r
petition is based both on a misunderstanding of the NRC's i
i practice in responding to 10 C.F.R. S 2.206 requests, and on invalid data. Upon receipt of a 10 C.F.R S 2.206 request the J. NRC makes an inquiry appropriate to the facts asserted.
. .- Consolidated Ediscn Company of New York (Indian Point, .
Units 1, 2, and 3), CLI-75-8, 2 NRC 173, 175 (1975). The requestor has an obligation to set forth the basis for the request, since the NRC is not required to develop such facts or to assume that they exist. Public service Company of I
In general terms, the reference temperature is'a calculated number that roughly corresponds to the temperature below which a precipitous drop occurs in the fracture toughness of metal.
l
- ~.
Indiana (Marble Hill Nuclear Generating Station, Units 1 s 2) ,
CLI-80-10, 11 NRC.438, 443 (1980). The NRC can rely on _
information from a variety of sources, including staff analyses of generic issues, and need only explain the basis of its decision. Northern Indiana Public Service Company (Bailly Generating Station, Nuclear-1), CLI-78-7, 7 N.R.C. 429 (1978),
aff'd Porter County Chapter v. Nuclear Regulatory Commission, 606 F.2d 1363 (D.C. Cir. 1979).
\ The NRC cannot reasonably b'e expected to address all documents in its possession which may touch on the subject i matter of a 10 C.F.R. S 2.206 request. Depending on the issue raised there may be literally thousands of documents which discuss various aspects of technical concerns involving the l -
regulation of nuclear power plants. It may well happen that the agency has material in its possession which has a facial i
! relevance to the subject but which in fact is inaccurate or misleading for reasons that are apparent to experts in the i field. The agency in explaining its decision need not go off
~.
6 -
-- on a tangential discussion of the material it is not relying; on, particularly when the request neither specifically identified such material nor suggested that it may be relevant. Rather, the agency need only provide a reasoned basis for its decision, as was done in this case.
As explained in the attached affidavit of Pryor Randall, the NRC had good reason not to rely on the 1976 data now cited by Ms. Lorion when it denied her request in 1981.
Those data are currently invalid, and were invalid in 1981, as 3
"I . _ _ . _ _ _ _ _ _ _ _ _ _ _ _ .__ _ _ _ _ _ __ _ _ __
a method for determining the embrittlement of the reactor vessel in Unit 4. Moreover, the agency has appropriately used data from all plants to develop an equation for determining embrittlement at individual plants, including Unit 4, and, contrary to petitioner's assertions, there is no " alchemy" involved. Hence, there was no reason for the agency to address the 1976 data'in its 1981 decision.
In sum, the NRC cannot be expected to address the
\ significance of every document in its possession in responding
. to a 10 C.F.R. S 2.206 request. The 1976 study at issue here was invalid by 1981. Accordingly, there was no reason for the
= ~.
4
~
agency to discuss that document in .its decision. Ms. Lorion's new arguments should be summarily rejected by this Court.2 Respectfully submitted, (
\
M x x- n WILLIAM H. BRIGGS ,(JI{/
So'licitor E.
A+
LEO SLAGGIE 6/ V
. Deputy Soliditor
~
DVA.A -
RICHARD P. LEVI Attorney Office of the General Counsel U.S. Nuclear Regulatory Commission Washington, D.C. 20555 OHN BRYSON M/ '
Attorney Land and Natural Resources Division
. U.S. Department of Justice Washington, D.C.
4~ _.
Petitioner Lorion also appears to be arguing that the Court should order the agency to address this additional information under 28 U.S.C. S 2347 (c) . Petitioner's new information does not meet the standards of 28 U.S.C.
S 2347(c). As indicated in the attached affidavit, the data is invalid, and hence it is not material. Moreover, petitioner has failed to offer adequate justification for not presenting the data before this late date.
Even if petitioner had met the standard of Section 2347 (c) , moreover, a remand to the agency would not be justified, because petitioner's appropriate remedy would be to file a new 10 C.F.R. S 2.206 petition. See Ramirez-Gonzalez
- v. Immigration and Naturalization Service, 695 F.2d 1208, 1213-14 (9th Cir. 1983); Alaska Steamship Co. v. Federal Maritime Commission, 356 F.2d 59, 63 (9th Cir. 1966).
5
. s. .
DECLARATION OF PRYOR N. RANDALL
- 1. My name is Pryor N. Randall. I am employed by 1
the Nuclear Regulatory Commission in the Office of Research.
I am making this affidavit in support of the NRC's response to Ms. Lorion's Supplemental Reply Brief. Ms. Lorion relies on a
~
1976 document, Pressure Temperature Limitations for the Turkey Point Unit Nos. 3 and 4 Nuclear Power Plants, Southwest Research Institute Project No. 02-4383-039 (June 30, 1976), to
- argue that pressurized thermal shock (PTS) is a current, serious concern at Turkey Point, Unit 4. As explained below, the data from the 1976 study were not valid in 198-1, and are i
not currently valid.
- 2. Petitioner Lorion to support her argument j-- - . . .
primarily relies on the results from the Charpy tests on the metals from a surveillance capsule from Unit 4. Based on the i
results of those 1976 tests, the Southwest Research Institute
{
projected that the RT a ur ey o n , Unit 4 would be NDT 340*F after ten equivalent full. power years (EFPY). As l petitioner Lorion notes, this would exceed the Commission's current screening criterion of 300'F.
l l
l l
l .. .
6 oo e
r However, there are two major flaws in pet'itioner's reliance on this single data point. First, it is inappropriate to rely on a single data point, such as a Charpy test, to determine vessel embrittlement. Surveillance data like that in the 1976 study have been shown to produce a wide scatter, i.e., they have a' wide error band, and are useful only to determine trends and statistical probabilities. The 1
Commission therefore does not permit the use of results from plant specific capsule tests to show'that a vessel meets, or does not meet, the screening criterion. Rather, the
! Commission used the results of Charpy tests from many plants i __
to develop an equation that can be used to calculate individual vessel embrittlement. Under this equation, the G'
. RT value is determined essentially as a function of the NDT copper and nickel content of the vessel materials, and the intensity of the neutron bombardment to which they have been i subjected. This method was used by the NRC in 1981 to
( -
determine the embrittlement of Turkey Point, Unit 4, and is~
2 d[ _, more accurate than the single point method used in the 1976.
study. This method is also that adopted by the Commission in its 1985 rulemaking.
Second, the 1976 data point was. measured at a Charpy energy level of 42 ft. lb. The Commission's regulations, which were issued in proposed form on November 14, 1980,
)-
2
- 45 Fed. Reg. 75536, require that measurements be taken at a Charpy energy level of 30 ft. lb. 10 C.F.R. Part 50, . App. G, S II.E. The Commission has determined (as demonstrated by that rulemaking) that the 30 ft. lb. level more accurately represents the change in material properties (fracture toughness) resulting from 5 utron irradiation, i.e. , the vessel embrittlement. If the 30 ft. lb. value is applied to i the 1976 data, then the projected ten EFPY RT value w uld NDT g be within the Commission's current screening criterion.
- 3. Ms. Lorion also criticizes the use of Unit 3 data for determining the embrittlement of Unit 4. Each lot of welding material used in nuclear reactors is somewhat different. Samples of various lots are put in the capsules.
Since PTS was not a concern when the Turkey Point reactors were built, it was not known at the time which weld would later turn out to be critical. It now turns out that no samples of the critical weld lot for Unit 4 were put in a l
J.
6
~
Unit 4 capsule, although some were put in the capsules in
-- Unit 3. Thus a more accurate data point of embrittlement of the critical weld in Unit 4 can be obtained by using the l
Unit 3 sample, corrected for differences from Unit 4, than from using the Unit 4 capsules of different welding material.
Contrary to Ms. Lorion's assertions, Petitioner's ,
i Reply at 15, the licensee letter dated October 23, 1981, which e
i 3
l
e . .
7 n an s a es that the value identifies an RTNDT.va ue f r "is based on Unit 3 data which has been shown to~be more representative of Unit 4 than the surveillance capsule removed s
from Unit 4," does not indicate that Charpy tests of Unit 3 capsules were used to determine the RT NDT of Unit 4. Rather, licensee used the chemical content of the Unit 3 surveillance capsule in the formula'for determining RT NDT, ecause, as noted above, the Unit 3 capsule is more representative of the
% critical weld in the Unit 4 vessel. 'Thus there is no.
. " alchemy", Petitioner's Reply at 14-15, in using Unit 3 surveillance data as an input into determining the l
~
embrittlement of Unit 4.
- 4. With regard to Professor George Sib's comments, see Petitioner's Reply at 17-18, his statements that embrittlement depends on the " combined effects of irradiation and pressurized thermal shock" and that the " loading history plays a major role," are unsubstantiated and are contrary to ik, the basic assumptions behind the NRC use of radiation damage b d'- ~
- - ' trend curves, which are derived from a compilation of data .
, from many reactors. See, e.g., Regulatory Guide 1.99.
l Professor Sih's views were considered as part of the PTS 1
I studies in the 1981-82 time period and were rejected as not being substantiated by tenhnical information.
6
\
l l
l .. .
L _ . - _ _ _ _ _ . _ ,
~, ,
- 5. The NRC on receipt of 10 C.F.R. 5 2.206 petitions reviews the information presented in the petition and other relevant documentation and explains itse decision. Since the 1976 data now cited by Ms. Lorion was not referred to in her petition, is invalid, and was invalid in 1981, the NRC did not find'it necessary to address this 1976 data, or' numerous other documents,.in order adequately to respond to Ms. Lorion's request.
g 6. In sum, to assess the safety of individual plants the Commission uses available data, corrected to allow for differences between plants, to determine both the amount of radiation at the location of the critical weld and the weld's ability to withstand that radiation. That was done for Turkey Point, Unit 4, in 1981, and those calculations are not x .
affected by the outdated 1976 data points.
I declare under. penalty of perjury that the foregoing is true and correct.
b.
'L . ... Executed on December _g[_, 1985. ,
I an aI 5
' ~
l
. ENCLOSURE 2 a ~. _
Notlee: This opinion is subject to formal revisJon before publication in the Federal Reporter or U.S. App.D.C. Reports.' Users are requested N to notify the Clerk of any formal errors in order that corrections may be made before the bound volumes go to press.
[ f Muitch 9tates Gaurt of Appeals i
POR THE DISTRICI OF COLUMBIA CIRCUIT l
No. 82-1132 JOETTE LORION, d/b/a CENTER FOR NUCLEAR RESPONSIBILITY, PETITIONER v.
UNITED STATES NUCLEAR REGULATORY COMMISSION and UNITED STATES OF AMERICA, RESPONDENTS FLORIDA POWER & LIGHT COMPANY, INTERVENOR On Petition for Review of an Order of the United States Nuclear Regulatory Commission l T. Argued December 16,1985
- - - Decided March 18,1986 .
Martin H. Hodder, with whom Terence J. Anderson, of counsel, was on brief for petitioner.
Richard P. Levi, with whom F. Henry Habicht, H, Assistant Attorney General, Herzel H. E. Plaine, General Bil:s of tes*a must be flied within 14 days after entry of judgment. The court looks with disfavor upen motior.s to file bills of costs out of time.
.v .
t I
= .
E^
r 2
Counsel, William H. Briggs, Jr., Solicitor, E. Leo Slaggie, Deputy Solicitor, Dirk D. Snel, and John A. Bryson were -
on brief for respondents.
Harold F.. Reis, with whom Holly N. Lindeman and .
Norman A. Coll, of counsel, were on brief for intervenor.
Before: MIKVA, Circuit Judge, and MAcKINNON and SwYGEnT,' Senior Circuit Judges.
g Opinion for the Court filed by Circuit Judge MIKVA.
MIKVA, Circuit Judge: For more than four years, Joette Lorion has been trying to force the Nuclear Regu-latory Commission ("NRC" or "the Commission") to take action against a nuclear power plant near Miami, Florida. She fears that the Turkey Point Unit #4 nu-clear reactor, which is owned and operated by Florida Power & Light Co. ("FPL"), contains unsafe equipment,
~ and that the danger of a nuclear accident is steadily in-creasing. Her crusade began with a letter to the Com-mission; since then it has grown to include a Sup2eme Court decision, and now a second trip to this. court.
Lorion raises a variety of legal issues, some of them quite complex. None of her contentions, however, can overcome the wide latitude that the NRC has in framing its criteria for hearings and its enforcement agenda. We
! ._ . hold that the NRC acted within its discretion in refusing l0 _
to hold a hearing, and therefore affirm the Commission's ;
decision.
L The nuclear fuel that provides the power in a reactor is packaged in rods. When in use, these rods are con-tained in steel pressure vessels inside the reactor. The -
~ steel walls of the vessel are constantly exposed to radia-tJon; this expo.oure causes the metal to become "embrit-
- i
- Of the United States Court of Appeals for the Seventh '
Circuit, sitting by designation pursuant to 28 U.S.C. 6 291(a) '
(3983). -
l
. ' sam ,
e
- 3 tied," ENich means that it is prone to cracking or shat-l tering when ' subjected to rapid changes in temperature oi pressure. These sudden changes are called "pressur-
, ized thermal shock" (" PTS"). The underlying issue in Lorion's appeal is the risk posed by PTS to the safety of the steel vessels in Turkey Point Unit #4.
s Excessive vessel embrittlement could lead to severe con-sequences. When a nuclear power plant is faced with an
~
emergency, one of its safety steps is to flood the reactor core with cold water. Without this water, the fuel rods could overheat and burn through the vessel walls, result-ing in an infamous " meltdown." The risk is that the sudden temperature change can cause embrittled walls or weld joints to crack, allowing the radioactive coolant water to escape. See generally Edelson, Thermal Shock-New Nuclear-Reactor Safety Ha:ard?, Popular Science, June 1983, at 55.
In 1981, concern about the embrittlement problem led petitioner, on behalf of the Center for Nuclear Respon-sibility (of which Lorion was the sole member) to write a short letter to the NRC concerning Turkey Point' Unit
,4. Her letter noted that the Commission itself had Wa' i
~~
identified this reactor as one of eight around the country that were vulnerable to cracking caused by PTS. Based on this, Lorion asked that the NRC initiate license review pmcedures, to consider suspending FPL's license until the reactor was proven safe. See Lorion v. Nuclear Regula-tory Commission, 712 F.2d 1472,1473 (D.C. Cir.1983).
The Commission treated Lorion's letter as an enforce-ment request under 10 C.F.R. I 2.206 (1985). Section 2.206(a) provides that Any person may file a request [with the NRC] to institute a proceeding pursuant to [10 C.F.R.]
-B; I 2.202 to modify, suspend, or revokeat license, or for such other action as may be proper. . . . The requests shall specify the action requested and set
+- "
4 forth the facts that constitute the basis for the re-put
- On November 5,1981, the NRC denied petitioner's re- m quest. Florida Power and Light Co.,14 N.E.C.1078 (1981). Th9 Commission stated that its staff had been studying the. situation, and that based on the available information, no immed,iate licensing action was necessary.
Id. at 1082-83. The reply acknowledged that embrittle-ment could present a long term problem, but it assured Lorion that it was monitoring Turkey Point #4, and that i the "NRC will take timely action in relation to the reac-tor ' vessel problem." Id. at 1083.
Lorion appealed, but this court dismissed for lack of subject matter jurisdiction. Lorion, 712 F.2d at 1478-79.
The Supreme Court reversed and remanded, ordering us to reconsider petitioner's claims on the merits. Florida Power & Light Co. v. Lorion,105 S. Ct.1598 (1985). On the same day that it decided Lorien, however, the Court also handed down Heckler v. Chaney,105 S. Ct.1649 (1985). In Heckler the Court held that the refusal by an agency to take enforcement action was presumptively unreviewable. The Lorion Court therefore invited us to consider the effects of Chaney on remand.105 S. Ct. at
, 1602 n.8.
(
The case is now before us again. Lorion's legal theory is that the NRC's decision not to take any enforcement
-. action was an abuse of discretion; for relief, she asks ei that this court instruct the Commission to order FPL to l "show cause" why its operating license should not be sus-I pended or revoked. In the alternative, petitioner claims l that the court should remand to the NRC for a reconsid-eration of her request, with the opportunity for her to provide additional evidence.
- II.
We first address the question of whether the NRC's decision not to issue a show cause order is reviewable. In l
M.
- sm o
1..
a .-
M 5 <
Heckler v. Chaney, the Supreme Court pointed out the m difficulties of appellate scrutiny of an agency's choice not to enforce its regulations in a particular case. The Court wrote that this type of decision "often involves a compli-cated balancing of a number of factors which are pecu-liarly within [an . agency's] expertise. . . . [t]he agency is far better equipped than the courts to deal with the many variables involved in the proper ordering of its pri-orities." 105 S. Ct. at 1656. Based on these considera-g tions, Chaney held that decisions not to enforce are " pre-sumed" to be " committed to agency discretion by law"
.. under the Administrative Procedure Act, and thus free from judicial review. Id.; 5 U.S.C. I 701(a) (2) (1982).
This presumption may be rebutted. A court may re-view a decision when the agency's governing statute pro-vides gni?.21ines as to when the agency must take en-forcement action. Chaney,105 S. Ct. at 1656-57; cf. Dun-
~ lop v. Bachowski,421 U.S. 560 (1975) (cited by Chaney as an example where governing statute gave court " law to apply"). The crucial consideration is whether Con-gress intended to circumscribe agency enforcement dis-cretion, and has provided statutory standards for the re-viewing court to follow.105 S. Ct. at 1657. Chaney did not decide, however, whether non-statutory standards could similarly restrict agency discretion; the Court
.~ "[left] to one side the problem of whether an agency's
,g- -
rules might under certain circumstances provide courts with adequate guidelines for informed judicial review of decisions not to enforce." Id. at 1658 (emphasis added).
The parties admit that the application of Chaney to this case raises difficult questions. Although we doubt that on tl.e facts be'oie us the NRC's discretion is re-stricted by the Atomic Energy Act, 42 U.S.C. Il 2011-
.. 2296 (1982), petitioner argues that the regulations and NRC precedent require the Commitsion to initiate action when certain types of health and safety issues are raised.
W M. , . . .
She also claims that the NRC's decision was not "analo-
. eb
M
~
6 gous" to the type of enforcement action before the Court
~
in Chaney, so that the presumption of non-reviewability does not apply.
Even though it is a " threshold" question, the court need not plumb the intricacies of this reviewability conundrum in the instant case. The merits of Lorion's underlying claims are sufficiently' clear that we can and should avoid the potentially far-reaching questions on the scope of Chaney. The decision to avoid a difficult threshold ques-i tion and resolve the substantive dispute is not new; both the Supreme Court and this court have used the proce-
" dure to restrict cases to their narrowest possible holding,
" particularly when the threshold question involves impor-tant constitutional or public policy issues. In Chinese American Civic Council v. Attorney General of the United States, 566 F.2d 321 (D.C. Cir.1977), we re-fused to decide a complex standing question, and instead resolved the underlying dispute. We found that "[p]ru-dential considerations also restrain us from deciding the
' difficult and unquestionably far-reaching standing ques-tion when the merits of the case readily provide a fair, clear resolution of the appeal." Id. at 325 (footnote omitted); see also Chandler v. Judicial Council, 898 U.S.
74, 86-89 (1970) (Court declined to reach jurisdictional question because petitioner failed to establish underlying i case). We find that this case presents a similar situation, and therefore turn to whether the Commission abused its
{ discretion in denying Lorion's enforcement request. -
III.
Petitioner makes three arguments that concern the merits of her appeal. First, she says that the NRC ig-nored its own policies and precedent in deciding not to institute a license review procedure. The NRC has ruled that whenever a request for enforcement is mede under ,
10 C.F.R. I 2.206, the Commission is required to issue a 2 . e.~
show cause order if it decides that "a substantial health 9
.< 7
'~
and safety issue" has been raised. Consolidated Edison Co. of New York, 2 N.R.C.173,176 (1975), cited in
\ Florida Power & Light v. Lorion,105 S. Ct. at 1601; In l re Philadelphia Electric Co., 22 N.R.C.149 (1985).
Lorion argues th~at the NRC has conceded that the in-tegrity of steel pressure vessels is a substantial safety issue, and that it was therefore an abuse of discretion not to take action.
Petitioner admits that the Commission never explicitly characterized the potential for vessel embrittlement as a
" substantial" safety issue. She notes, however, that in the NRC response to her letter, it referred to the reactor vessel " problem," and that in an unrelated policy state-ment, the NRC staff considered embrittlement a " safety concern." NRC Policy Issue, SECY-81-286, Enclosed Memo at 3-4 (May 4,1981) (April 28,1981 memo from Eisenhut to Denton). Even more significant, in Lorion's eyes,is a letter from the Commission to FPL, stating that the vessel embrittlement at Turkey Point Unit #4 was
" approaching levels of concern." Letter from Darrell G.
Eisenhut, Director, Division of Licensing, Office of Nu-l clear Reactor Regulation to Robert E. Uhrig, Vice Presi-dent, Florida Power & Light Co. (Aug. 21,1981). Be-
. cause of this concern, the letter required FPL to submit information, under oath, on the condition of the reactor.
2 c ' ~
Id.; see 10 C.F.R. I 50.54(f) (1985) (Commission au-thority to require additional information). ~~
l We cannot accept the contention that the NRC has im-l plicitly categorized the concerns raised by petitioner as
} " substantial health and safety" problems. This phrase is
)
a term of art within the Commission, because it is the language reserved as a trigger for action rather than a description of the severity of the concern. The language of the Commission's references here shows that it consid-
' ered embrittlement a problem, but not necessarily a "sub-Mi stantial" problem that would mandate a hearing proce-dure. The Commission's precedents make it clear that it
a
- 8 e is not obligated to take enforcement action "whenever
,1 we receive information adverse to the integrity of existe
{
ing nuclear power safety or safeguard systems." In re Nuclear Regulatory Commission, 5 N.R.C.16, 21 (1977),
citing N'ader v. Nuclear Regulatory Commission, 513
. F.2d 104$,1054-55 (D.C. Cir.1975). We are not con-vinced that the NRC decided that embrittlement was a
. substantial issue simply because the problem was "ap-proaching levels of concern."
% The broader question of whether a particular issue should be considered substantial, and thus whether en-forcement action is required, must be left to the Com-mission's discretion. Porter County Chapter v. Nuclear Regulatory Commission, 606 F.2d 1363,1869 (D.C. Cir.
1979). We find that the NRC reasonably concluded with respect to Turkey Point Unit #4 that this was not such an issue at this time. As it pointed out in the re-sponse to Lorion's letter, the Commissien had been study-ing the pressure vessel problem and had concluded that the risk to public health was very low. It acknowledged that there was the potential for problems in the long run, but noted that it was working to correct the matter through an ongoing, plant-specific investigation. Florida Power and Light,14 N.R.C. at 1083. Based on the record, we cannot say that the Commission abused its i discretion in refusing to consider Lorion's concerns "sub-
.f~ ' stantial," or to institute a licensing procedure, t
Petitioner's second claim is that the NRC's rejection of her enforcement request was arbitrary because it failed to consider all the relevant evidence. She argues that two critical documents-which she believes clearly show the danger of the reactor-were never mentioned I by the Commission in its response to her letter. In her brief, Lorion also provides a long list of other docu-ments that were available to the Commission, but that either were not mentioned or not discussed in the reply.
She suggests that the failure to even acknowledge the 1
l l
M r
l l
l r.
E_, , ,
i 9 evidence means that it was not properly considered, and that the ultimate decision was therefore irrational.
The twdtcrucial documents Lorion cites both purport to show that the steel vessels at Turkey Point are em-brittled beyond safe levels. The first is a 1976 report to the NRC, stating that the embrittlement in Unit #4 was both higher than expected and higher than the embrittlement in Unit #3. The second document is the
't response by Florida Power to the NRC request for information. In this response, FPL supplied data to show the condition of reactor Unit #4, based on data gathered from Unit #3; the company concluded that it was "more representative" of the conditions at Unit #4 than the Unit #4 data itself. Lorion implies that FPL is trying to camouflage the problems with the #4 reactor by presenting irrelevant evidence.
It is true that an agency has a duty to consider all the evidence, and to explain its decision fully. City of Charlottesville v. Federal Energy Regulatory Commis-sion, 661 F.2d 945, 950 (D.C. Cir.1981) ; Asarco Inc. v.
Environmental Protection Agency, 616 F.2d 1153,1159 (9th Cir.1980). It does not necessarily follow, however, that the failure to mention certain evidence means that It was not considered, nor does it follow that an explana-l-. tion is incomplete unless it dutifully lists all the evi-3 o ' ~ dence that the Commission examined. The NRC's denial l of a request for a show cause order will be upheld as i long as all the necessary factors were considered, and l '
provided that the statement of reasons given permits a
" rational understanding of the basis for [the] decision."
l Consolidated Edison Co., 2 N.R.C. at 175; see Motor Vehicle Manufacturers Association v. State Farm Mutual Automobile Insurance, 463 U.S. 29, 43 (1983).
The Commission easily met its obligation here. The basis of the NRC's decision was explained in sufficient detail to allow this court to conduct a meaningful re-l view. There will be times, of course, when a reasoned
? "
- s. .
l 10 e response is impossible without a discussion of contrary evidence, particularly when that evidence is mentioned 3
in the enforcement request. But as long as the Commis-sion's reply fairly addresses the issues raised, the failure to rebut every argument raised by petitioner is not a per se abuse of discretion. To require the NRC to men-tion and analyze every document relevant to a hearing request would completely clog an agency's decisional process. There is nothing in administrative law that s allows a complainant to filibuster the processes with a huge number of documents.
' Lorion's final argument warrants only brief mention.
She asks this court to consider the evidence on embrittle-ment and reverse the NRC's decision; she claims that the overwhelming evidence makes its " impossible" to conclude that no substantial safety issue was presented.
This misinterprets our scope of review, and ignores the latitude we must afford the Commission's decisions.
Courts are required to give their highest level of defer-ence to decisions involving novel questions at the "fron-tiers of science." Baltimore Gas & Electric Co. v. Na-l tional Resources Defense Council, 462 U.S. 87,103 l (1983). The susceptibility of steel reactor vessels to ;
pressurized thermal shock seems to be just such an issue.
We would only overturn the Commission's decision if-it l, were completely unsupported by the record; because
,o that is not the case, we decline to substitute our judg-l
~
ment for that of the NRC's. See Porter County, 606 F.2d at 1367-70.
CONCLUSION The NRC provided a reasoned explanation for its de-cision in this case and thus it did not abuse its discre-tion by refusing to issue a show cause order. We have considered the rest of petitioner's claims, and find them similarly unpersuasive. We therefore affirm. -
It is so ordered.
i
.