ML17252B505

LER 77-050/03L-0 for Dresden, Unit 2 Re Local Leak Rate Test of Drywell Personnel Air Lock During Refueling

ML17252B505
Person / Time
Site:	Dresden
Issue date:	11/03/2017
From:	Stephenson B B Commonwealth Edison Co
To:	Keppler J G NRC/RGN-III
References
BBS LTR 1030-77 LER 77-050/03L-0
Download: ML17252B505 (3)

Text

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*------Commonw. Edison Dresden Nuclear Power Station R.R. #1 Morris, Illinois 60450 Telephone 815/942-2920 --------------------------------Novembe}'." i 1977 BBS LTR t/1030-77 James G. Keppler, Regional Director Directorate of Regulatory Operations -Region III U.S. Nuclear Regulatory Connnission 799 Roosevelt Road Glen Ellyn, IL 60i37 . Reportable Report _Docket #050-0237 is

• hereby to yotir off in with Dresden Nuclear Power Station Technical Specifications 6,6,B,2,d., abnormai dation of systems designed to contain radioactive material ing from: :the f.ission process, BBS:dlz Enclosure Stephenson i-Superintendent Dresden Nuclear Power Station* cc: Director of Inspection & Enforcement Director of Management Information & Program Control File/NRC . 1 \911 J -: i I 17-77) e 'LICENSEE EVENT REPORT e CONTROL BLOCK: I I ' I I 10' (PLEASE PRINT OR TYPE ALL REQUIRED INFORMATION) ., .... ,

• 1 6 r 1 1 L 1 n 1 R 1 s 1 2 101 o 1 o 1 *. 1 o 1 o 1 o 1 o 1 o 1 ... 1 o 1 7 . 8 9 LICENSEE CODE 14 15 LICENSE NUMBER 0101 4J ll ll ll 1101 . I I G) 25. 26 LICENSE TYPE ;JO 57_ CAT 58 CON'T . _ *1-o-1-+1-I© I--01 -5-1 ** 0-i-0-1-0 -1--2-1-J-1*-:-7--IE.)1--1-1-0-1-2-11-1--7 -1-7-1@ 1---i-1---1-1--0-1-3-1-7-1-7-+@ 7

• 8 60 61 DOCKET NUMBER 68 69 EVENT DATE 74 75 . REPORT DATE 80* EVENT DESCRIPTION AND PROBABLE CONSEQUENCES (,0) . [Q:ITI I. During local leak rate test of Drywill lock during refueling, measured [QTIJ [2TIJ leakage was 40.207 SCFH. Leakage :was found through the inner door equalizing valve (ie, Drywell to airlock). Assuming all leakage was through this valve. T.S.4,7.A.2,f, (2),(b) single valve leakage limit (5%'.Cto = 29,3 SCFH) was exceeded. This event had -.._ I little safety significance since the penetration through leakage was less than the T.S. limit, This is the first event involving excessive leakage through an air lock __________ 7 8 9 80 [ill] 7 8' SYSTEM CODE 15 IA I@ 9 10 LER/RO LVENT YEAR REPORT I 7 I 7 I NUMBER 21 22 CAUSE CAUSE CODE SUBCODE COMPONENT CODE L!J@ vi Al LI VI El x1@ 11 12 13 18 SEQUENTIAL OCCURRENCE REPORT NO. _ CODE I I 1°151°1 1.....-1 I Ol 31 23 24 26 27 28 29 COMP. SUBCODE 19 REPORT TYPE 30 VALVE SUBCODE 20 l.=J 31. ACTION FUTURE EFFECT SHUTDOWN (.:;::;\ ATTACHMENT NPRD-4 PRIME C.OMP. SUPPLIER REVISION NO. 32 COMPONENT MANUFACTURER TAKEN ACTION ON PLANT METHOD HOURS SUBMITTED FORM SUB. I 01 01 01 01 L!!J@ LIU@ 33 34 35 36 3 7 40 41 42 I JI o 1*1 I q@ CAUSE DESCRIPTION AND CORRECTIVE ACTIONS @ 43 44 ' 47, o::I]] I The leaking valve was disassembled, The valve seating surfaces were found to be dirty;j Also, outer seats were loose. The valve was cleaned and reassembled. The personnel ITITI air lock retested with a measured leak rate of 15,912 SCFH which is within the T.s.1 [ill] L.I _1_i_m_i_t_. __ N_o_f_u_r_t_h_e_r_a_c_t_i_on __ i_s_r_e..:q..:u_i_r_e_d_. __ T_h_e_v_e_n_t_v_a_l_v_e_i_s_a_3_i_n_c_h--']::i_a_1_1_* v_a_l v_e_m_o_d_e_l _ __. ITill 113 D22NN. 7 8 9 80 FACILITY STATUS % POWER OTHER STATUS Em L!J@ I 0 I 0 I 0 l@) ..... I ___ N_A __ _, 8 9 10 ' 12 13 AC.TIVITY CONTENT RELEASED OF RELEASE AMOUNT OF [2li] @) NA 7 8 9 10 11 7 44 METHOD OF A DISCOVERY DISCOVERY DESCRIPTION ___ L_o_c_a_l_._L_e_a_k_R_a_t_e_T_e_s_t_in_g;;__* ___ -'-___. 45 46 80 LOCATION .OF RELEASE@ ,__ _________________ N_A ______________ __,I 80 44 45 PERSONNEL EXPOSURES Q\ NUMBER A TYPE DESCRIPTION [iI2J I 0 ., 0 I 9J6LJJ@L.,.-______________ NA ___ ...,.-_____ ___, 7 8 9 11 12 13 80 PERSONNEL INJURIES (,;:;\ NUMBER ITfil I o I ol ol@"-----------------_,;;,;N=A _________ __. ' 7 8 9 11 12 80 LOSS OF OR DAMAGE TO FACILITY t4J\ TYPE . DESCRIPTION . ' ', NA 7 8 9 10 so NRC USE ONLY 0 [ill] I I I I I I I I* I I I I 8 9 10 68 69 80 ;; Mike Pqrcell NAME OF.PREF!ARER------------------PHONE:.;.* ______ ...__2_6_5 __ _ 0 a. "

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