ML20151A008
| ML20151A008 | |
| Person / Time | |
|---|---|
| Site: | Trojan File:Portland General Electric icon.png |
| Issue date: | 06/21/1988 |
| From: | Dixon B ENERGY, DEPT. OF |
| To: | Martin J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| References | |
| NUDOCS 8807190202 | |
| Download: ML20151A008 (4) | |
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G u) n Department of Energy myt 625 MARION ST. NE, SALEM, OREGON 97310 PHONE 378-40'40 TOLL FREE 1800 2218035
'h June 21, 1988 1
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- e Jack Martin, Administrator Region V, Nuclear Regulatory Commission 4
1450 Maria Lane, Suite 210 4
v.1 Walnut Creek, CA 94596-5368
Dear Jack:
I wrote you on June 10 about our current actions concerning Trojan and the Northwest earthquake potential.
We conducted the June 16 meeting announced in that letter to consider this issue.
Information provided at the meeting helped us to better understand the earthquake issue.
After review, we concluded that PGE has been responsive to earthquake issues.
We cannot conclude the current Northwest earthquake study findings indicate hazards greater than Trojan can withstand.
However, we need to keep abreast of findings the studies will produce.
We need to ensure that any Trojan impacts implied by these findings are fully resolved in a timely way.
The enclosed copy of our letter to Duke Cockfield best explains our position.
At the last Energy Facility Siting Council meeting April 28, Forelaws On Board presented two petitions.
The group asked for a contested case proceeding to shut Trojan down because of the earthquake study findings.
The Council asked two of its members to review the issue.
The two are to recommend action at the next Council meeting June 30.
The Council will then rule on the petitions, We know that the NRC has extensive programs dealing with earthquakes.
However we have only vague information on the extent of those activities.
We and the Council need to know more.
We invite you or your representative to address the Council June 30 on NRC earthquake activities.
We believe that will help the Council make an informed decision on the petitions.
Mike Alsworth, of my staff, will give you any information you need.
If you have any questions of other needs, please call me.
I will be at my office the week of June 27.
Sincerely, N
bv-Bill Dixon, Administrator Nuclear Safety & Energy Facilities BD:HFM/ml/9062o(d2/f2) f 8807190202 880621 3
Enclosure DR ADOCK 050 4
p The Oregon Department of Energy is an Equal Opportunity Employer
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o aCCtN Qiff Department of Energy ggt 625 MARION ST. NE SALEM, OREGON 97310 ' PHONE 378 4040 TOLL FREE 1800 2218035 June 21, 1988 Duke Cockfield Vice President, Nuclear Portland General Electric 121 SH 3almon Street Portland, OR 97204
Dear Mr. Cockfield:
This letter states the Oregon Department of Energy's (0 DOE's) conclusions on the potential inpact of large earthquakes on Trojan.
He believe that Trojan can withstand the largest earthquakes now postulated for this region without endangering the public.
There is no reason to expect that even larger earthquakes will be postulated.
- But, we believe that cogoing programs are needed to evaluate new geologic ir. formation and to confirm that Trojan's safety still is assured.
We accept Portland General Electric's (PGE's) conmitment to such a program. ODOE will intensify our own review of that program.
We will coordinate our work with the NJclear Regulatory Conmission's (NRC's) review.
Authorities The NRC has broad federal authority to regulate connercial nuclear power plants.
Oregon law requires us to employ optimun state jurisdiction.
In doing so, 000E is to work with federal agencies.
State law charges ODOE with the day-to-day regulation of Trojan. State law gives ODOE power to order actions if:
there are violations of state safety standards; or, if there is a clear and present danger to public health and safety. ODOE has long cooperated with HRC on health and safety concerns as regard Trojan.
Background
Soc.e years ago, geology experts began to look into the possibility of large and severe earthquakes in the Pacific Northwest.
Studies have focused on the Cascadia subduction zone.
PGE, NRC, and ODOE began to follow these studies and what they might imply about potential impacts on Trojan.
l l
The Oregon Department of Energy is an Equal Opportunity Employer
Duke Cockfield hf x C
q June 21, 1988 Page 2' Two years ago, the U.S. Geological Survey (USGS) launched a five-year study of the earthquake issue.
NRC is funding 40me of -the USGS effort.
Early results indicated that there may have been large subducticn earthquakes long ago.
ODOE asked PGE to step-up its review and retain outside expertise.
PGE has done so.
On May 16, 1988, ODOE sent a list of questions to PGE.
The intent was to assess the level of scientific knowledge and consensus about whether large subduction zone earthquakes could occur and, if so, how severe they might be.
The questions also were to help evaluate the impact of such earthquakes on Trojan.
PGE's answers were in a report dated June 6, 1988.
On June 16, 1988, ODOE met with PGE and its outside experts to review PGE's responses.
Others at the meeting were Forelaws on Board; the Oregon Department of Geology and Mineral Industries; ODOE's structural consultant, Dr. Hal Laursen; and two members of the Energy facility Siting Council (EFSC).
Findings Based on ODOE's technical review, we found:
- There remains some doubt among experts that there have been or could be large subduction zone earthquakes.
But, the geologic community i
appears to be leaning toward general agreement the region has had such earthquakes -- and could again.
But, experts do not agree on the size and character of such earthquakes.
- The largest earthquake yet postulated in the USGS study is as severe as the worst on record -- in Chile in 1960.
There is cause to believe that in such an earthquake the ground notion at Trojan would be within the plant's design limits.
- There is enough margin in Trojan's design and construction to support high confidence that the plant can withstand an earthquake equal to the worst ever -- without danger to public health and safety from radioactive releases.
- There is no evidence that the state's safety standards for Trojan are being violated.
NRC believes that Trojan meets federal safety standards.
Conclusion We believe that Trojan can withstand the largest earthquakes now being postulated in the USGS study without danger to the public.
There is no reason to expect that even larger earthquakes will be postulated.
Further, we believe that Trojan meets safety standards for protection i
against earthquakes.
At the same time, we believe that ongoing programs j
are needed to evaluate new geologic information and to confirm that Trojan's safety still is assured.
Duk'e'Cockfield'O-t*.
O June 21, 1988
?
Page?3 000E Directive for PGE Actions We accept PGE's commitment to continue to follow ad evaluate the issue.
We direct that:-
1.
PGE shall continue'to retain and use the needed outside technical expertise.
2.
PGE shall write a specific action plan by which it will continue to follow, gather, and evaluate new information.
The plan shall. address:
a.
The possibility of large subduction zone earthquakes; b.
The size and character of such' earthquakes; c.
The impact of-such earthquakes on the ground motion _at Trojan; d.
The impact of such ground motion on plant structures and equipment that protects.the public, and e.
The extent original design margins might be reduced; if so, whether there should be action to restore those margins.
3.
PGE shall review to the action plan and make needed changes every three months.
4.
PGE shall cooperate fully with ODOE's independent review of PGE's program.
ODOE's Commitment ODOE will intensify our independent review of this issue. - We will get outside technical experts to help us.
We will continue to work closely with the NRC.
We will give EFSC members copies of this letter.
Members can then to consider it in their resoonse to Forelaws on Board's' petition to suspend Trojan's site certificate.
And, we will keep EFSC and other interested officials abreast of our review.
Last, I commend PGE's Nuclear D_ivision staff for aggressive, thorough, and cooperative actions to address this important issue.
Sincerely, i
I
'l l
g David V. Yade Director DVY:ml f
9055o(d3/fl) cc:
Jack Martin NRC Region V
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