ML20207G697
| ML20207G697 | |
| Person / Time | |
|---|---|
| Site: | Seabrook  |
| Issue date: | 12/23/1986 |
| From: | Devincentis J PUBLIC SERVICE CO. OF NEW HAMPSHIRE |
| To: | Noonan V Office of Nuclear Reactor Regulation |
| References | |
| SBN-1260, NUDOCS 8701070378 | |
| Download: ML20207G697 (3) | |
Text
.
O SEABROOK STATION I
Enginr: ring Offict December 23, 1986 Pubuc Service of New Hampshire SBN-1260 New Hampshire Yankee Division T.F.
B7.1.2 United States Nuclear Regulatory Commission Washington, DC 20555 Attention:
Mr. Vincent S. Noonan, Project Director PWR Proj ect Directorate No. 5
References:
(a)
Facility Operating License NPF-56, Construction Permit CPPR-136, Docket Nos. 50-443 and 50-444 (b) PSNH Letter (SBN-945), dated February 14, 1986,
" Meeting Notes Instrumentation and Control Systems Branch", J. DeVincentis to V. S. Noonan (c) PSNH Letter (SBN-1212), dated October 9,1986, "Veritrak/Tobar Transmitters", G. S. Thomas to V. S. Noonan (d) Rosemount Report D8300076, Revision A, " Accuracy of Pressure Transmitters, Rosemount Model 1153 Series B or D, Under Combined DBE Conditions",
dated June 6, 1983 Subj ect :
Setpoint Methodology
Dear Sir:
During a recent discussion with the Staff, New Hampshire Yankee (NHY) was requested to provide information concerning the setpoint methodology for the Rosemount transmitters. In response to this re-quest, NHY is providing the following discussion which briefly de-scribes the existing methodology and the methodology NHY intends to use for the Rosemount t ransmi t te rs.
In Reference (b), (response to RAI 420.8), NHY verified that the safety-related instrument channel setpoints were developed using the Westinghouse methodology as approved by the NRC.
This methodology pro-vides a method of combining error components for an instrument channel by statistically combining independent erroro using the Root Sum Squares (RSS) method and adding the dependent error components arithmetically.
\\
W'd 8701070378 861223 PDR ADOCK 05000443 P
~
P.O. Box 300. Seabrook, NH 03874. Telephone (603) 474-9574
.%- J United ~ States Nuclear Regulatory Commission SBN 1260 Attention:
Mr. Vincent S. Noonan Page 2-Reference (c) stated that NHY will be replacing certain Westinghouse-supplied transmitters (pressurizer pressure, pressurizer level, and steam generator level) with Rosemount transmitters.- Rosemount has issued a report [ Reference' (d)], which provides their basis 'and recommendations for combining error components. In this report, Rosemount considers that the post-accident environmental error (which includes the seismic, radiation, and high-energy line break errors) to be statistically inde-pendent and recommends that it be combined with the other statistically independent channel errors using the RSS method. This report is' avail-able for the Staff's use in NHY's Bethesda Licensing Office. Therefore, based upon Rosemount's recommendation,- NHY will calculate the safety-related trip setpoints for the new Rosemount transmitters using the RSS method and will include the post-accident environment error as an inde-pendent error under the radical.
'In this regard, it should also be noted that NHY also intends to use the same philosophy for future setpoint calculations.
If the independence of an error component _can be demonstrated, then this component will be in-cluded under the radical.
NHY trusts that the above is acceptable and request that this be re-flected in the next supplement to Seabrook's SER.
Since the Rosemount-transmitters are expected to be available soon, in order that they can be installed during February,1987, NHY also requests that the Staff indicate
-its approval of this methodology by January 16, 1987.
Very truly yours, g
da John DeVincentis Director of Engineering cc: Atomic Safety and Licensing Board Service List
l
- Disn3 Curren, _ Esquire-Pater J. Mathtws, Maysr Harmon & Weico-City Hall i
F 2001 S. Street, N.W.
Newburyport, MA 01950 Suite'430~
Washington, D.C.
20009 Judith H. Mizner Silvergate, Gertner, Baker, Sherwin E. Turk, Esquire.
Fine, Good & Mizner Office of the Executive Legal Director 88 Broad St.
2 U. S. Nuclear Regulatory Commission Boston, MA 02110 Tenth Floor-Washington, DC 20555 Calvin A. Canney City Manager Robert A. Backus, Esquire City Hall 116 Lowell Street 126 Daniel Street P. O. Box 516 Portsmouth, NH 03801 Manchester, NH' 03105 Stephen E. Merrill, Esquire C
Philip Ahrens, Esquire Attorney General Assistant Attorney General George Dana Bisbee, Esquire Department of the Attorney General Assistant Attorney General Statehouse Station #6 25 Capitol Street Augusta, ME 04333 Concord, NH 03301-6397 Mrs.-Sandra Gavutis Mr. J. P. Nadeau Chairman, Board of Selectmen Selectmen's Office RFD 1 - Box 1154 10 Central Road Kensington, NH 03827 Rye, NH 03870 9
Carol S. Sneider, Esquire Mr. Angie Machiros
' Assistant Attorney General
. Chairman of the Board of Selectmen Department of the Attorney General Town of Newbury One Ashburton Place,19th Floor Newbury, MA 01950
. Boston, MA 02108 Mr. William S. Lord Senator Gordon J. Humphrey
' Board of Selectmen U. S. Senate
. Town Hall -- Friend Street Washington, DC 20510 Amesbury, MA 01913 (ATTN:
Tom Burack) l Richard A. Hampe, Esquire Setidlot Gordon J. Humphrey Hampe and McNicholas 1 Pillsbury Street 35 Pleasant Street Concord, NH 03301 Concord, NH 03301
( ATTN:
Herb Boynton)
Thomas F. Powers, III H. Joseph Flynn, Esquire Town Manager Office of General Counsel Town of Exeter Federal Emergency Management Agency.
10 Front Street 500 C Street, SW Exeter, NH 03833 Washington, DC 20472 Brentwood Board of Selectmen Paul McEachern, Esquire RFD Dalton Road Matthew T. Brock, Esquire Brentwood, NH 03833 Shaines & McEachern 25 Maplewood Avenue Gary W. Holmes, Esquire P. 0. Box 360 Holmes & Ells Portsmouth, NH 03801 47 Winnacunnet Road Hampton, NH 03842 Mr. Ed Thomas Robert Carigg i
FEMA Region I Town Office 442 John W. McCormack PO & Courthouse Atlantic Avenue j-Boston, MA 02109 North Hampton, NH 03862
- -, - - - -