ML19256D746
| ML19256D746 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 02/07/1977 |
| From: | Pasedag W Office of Nuclear Reactor Regulation |
| To: | Bunch D Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 7910220675 | |
| Download: ML19256D746 (3) | |
Text
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3 D' g, FEB 7 1977 [ p PEMORANDUM FOR: D. F. Buncn, Cnief, Accident Analysis Brancn, DSE FROM: W. F. Pasedag, Safeguards Engineer, Operating Reactors Safeguards Branch, DOR
SUBJECT:
THREE MILE ISLM D CONTAINMENT SPRAY On Friday, February 4,1977, I attended a meeting wita representatives of GPU and Burns and Roe concerning the coverage of tne contairJDCnt aChiGVed with the spray system on Three Mile Island Unit ao. 2. With the aid of full size blueprints, and detailed calculation of containment volumes performed by Burns and Roe, a list of unsprayed volumes was reviewed. This list is attached as Table I. In addition the post-accident operation of the contairunent fan.:ooling system was discussed. I I re ocunend that i:his list be used as a basis for modeling tne sprayed and us.;croyed regicas in the containment. The containment model wnica would best. Mscribe the Three Mile Island containment would consist of three sepante regions, witn the volumetric distribution and mixing parameters listed ;n Table II. h/ W. F. Pasedag, Safeguardr. Engineer Operating Reactors Safeguards Branch Division of Operating Reactors
Enclosures:
As stated Distribution / Central File cc: R. Clark, DOR hKK Reading H. Silver, DPM W. Pasedag L. Soffer, DSE C. Ferrell, DSE 1453 217 P. Tam, DSE 7M ppK 79102 0675 g b or Fd a D-WPaied g/bm.. _ 2/7/77 Form AEC 3!$ (Rev. 9 53) AECM 0240 W u. e. oover disant enmvine orricas seve.saa-see
m 's TABLE I THREE MILE ISLAND UNIT NO. 2 CONTA*NMENT REGIONS 3 Volume (ft 1 Reaion_ Description 1. Above operating floor elevator shaft 8,258 A 2. Inside secondary shield below missile shield and fuel handling bridges total volume 61,840 Bl directly sprayed through openings in bridge structure 5,880 02 3. Around S.G., shielded by insulation (S.G. compartment open on top) 6,435 C 4. Pressurizer cubicle (pressurizer cubicle closed on top) 9,708 D 5. Below reactor coolant pump motors (open on all sides) 9,149 E 6. Below operating floor, between elevation 305' and 347' total volume (includes the following regions) 293,135 F0 elevator shaft 10,285 F1 directly sprayed through open hatches 28,215 F2 stairwell 3,870 F3 below fan coolers
- 8,120 F4 7.
Selcw elevation 305' (all unsprayed) 106,250 G ~~ Tan"c~oTiers: minimum oTUans (34,000 cfm, ea.) cpera tional. Ficw rates ~ distributed as follows: 50,000 cfm mixing of upper region of containment 18,000 cfa mixing bet.,een upper region and lower compartments 1453 218
s TABLE II RECOMMENDED MODELING OF THREE MILE ISLAND UNIT NO. 2 CONTA A. Nodes 6 3 ~ 1. Sprayed region: 1.68 x 10 ft Unsprayed regions with good communication with directly sprayed 2. 3 regions: volumes (B1-B2) + C + E + F3 + F4 = 84.000 ft Unsprayed regions with poor comrunication with sprayed regions: 3. 3 volume ~s A + E + (F0 - F2 - F3 - F4) + G = 395,000 ft B. Mixing Rates Between sprayed and unsprayed regions with good communication: 1. 1 turnover of unsprayed region per minute Between sprayed and unsprayed regions with poor communication: 2. 2 turnovers of unsprayed region per hour plus 18,000 cfm enhancement of mixing rate from fan-coolers 1453 219 ..}}