ML20210K102
| ML20210K102 | |
| Person / Time | |
|---|---|
| Site: | 07000036 |
| Issue date: | 08/12/1997 |
| From: | Sharkey R ABB COMBUSTION ENGINEERING NUCLEAR FUEL (FORMERLY, ASEA BROWN BOVERI, INC. |
| To: | Weber M NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| References | |
| NUDOCS 9708190144 | |
| Download: ML20210K102 (14) | |
Text
{{#Wiki_filter:9) 00 *h hll $iIn August 12,1997 Dock'et No. 70-36 License No. SNhi 33 hir hiichael Weber, Chief Licensing Branch Division of Fuel Cycle Safety and Safeguards, NhiSS Office of Nuclear hinterials Safety and Safeguards U.S. Nuclear Regulatory Commission Washington, DC 20555-0001
Subject:
Amendment Request for Unrestricted Release of flydrofluorie Acid
Dear hir. Weber:
Combustion Engineering hereby requests an amendment to its NRC license to permit release of hydrofluoric acid manufactured as a byproduct of the oxide conversion process for unrestricted commercial use as described in condition 1.6(h). Enclosed in support of this request are: (1) A pathway analysis for ilF scrubber liquid, including process and operations descriptions. (2) A statement of why an environmental assessment is not required. (3) Revised page 1-7," Exemptions and Special Authorizations," to the SNhi-33 license application, containing new condition 1.6(f). Also,' an ISA (hazard analysis) has been performed on the liF sembber liquid process in accordance with Chapter 2 of the license and all other applicable requirements. If there are questions regarding this matter, please feel free to contact Dr. Earl Saito of my staff at (314) 937-4691 Ext 461 or myself at (314) 937-4691 Ext. 399. Cordially, COh1BUSTION ENGINEERING,INC. Robert W. Sharkey Q [U L Director, Regulatory A0' airs ^ cc: Tim Reidinger Region ill RA97/611 100000 ABB CENO Fuel Operations \\\\ ho ene (314 937-4(91 I Cartushen Enge+mng kw 3W Stre Road P r 1 Fh Once Bas 107 St Lcus(31412%%40 ' * " 3 ' ' ' *3
- 9708190144 970812 i
PDR ADOCK 07000036, C PDR b
P:thway An:ly:Is f:r HF Scrubber Liquid f
Purpose:
This document has been prepared to support the request for authorization for unrestricted release of hydrofluoric acid (HF) from Combustion Engineering's (CE) facility in Hematite, Missouri. In order to support such a release, HF production rates and process, proposed license release guidelines, potential usage, and pathway analysis are included in this report. Process
Description:
UFe is converted to UO using a multi-stage " dry" conversion process. The UFs is 2 converted to UO F using superheated steam. The UO F is further processed 22 22 using disassociated ammonia (hydrogen) and superheated steam. The off gas is passed through two sets of sintered metal filters to remove particulate. Therefore, only gaseous effluents from this process are passed out to the scrubbing system. The wet scrubbing system captures the HF which then will be used as an industrial feed stock. A more detailed description of the conversion process may be found in Part ll of SNM-33. The advantage of using a wet scrubbing process, as opposed to the present use of a dry (calcium carbonate) scrubbing system is two fold. First a usable industrial feed stock is produced. Second the emission of HF gas to the environment is reduced due to the increased efficiency of the wet scrubbing process. Operational Details (Current): Approximately 300,000 kg(U)/ year of UO are produced by CE. This produces 2 approximately 100,000 kg(HF)/ year with ~10,000 kg(HF)/ year in stack emissions und a production of ~180,000 kg(CaF )/ year. 2 Wet Scrubber Operations: Currently, trace amounts of uranium that could pass through the metal filters is captured by the scrubber rock, The rock is routinely checked and found to have less than 30 pCl(U)/g%. At this level a design basis for the wet scrubber was established to ensure less than 3E-6 pCl(U)/mi during routine production. The HF scrubbers will be placed plant south-v,est of the current dry scrubbers (Figure 1). The HF solution will be created by a wet scrubbing process which removes HF vapors from the effluent and places them into a liquid form. The liquid is collected in a favorable geometry configuration (Figure 2). This configuration is set up such that different cells may be isolated mixed 1 Attachment to RA97/611
Pathway An:ly^1s for HF Scrubber Liquid I Figure 1 i i l e i u; 3 e* I a ah a r Fr c iI Je g,'. 7 0;o a I,,t, zw ru l N3 g "b' w(u/, 4 1 ti /lJ I bd , 4@, ,,i r= 1 o r.3 ss + Sci Y '} l' g g._ i og u, I L* Y g ? n? i Zi MP M"d Ofp ./ y. _. j \\ g" c, f.: i \\ t,. .= ,J 7, 3 i. y ,\\ li X i IL i v i i 12 ) f" I l .P e u 4 1 i iT Qa f i r N "l O o i t 3 ga-v i \\ j I "d 1 .I s 1 y 3 I l 'i k 0 4 i . o 1 i 1 i 3 i i ,1 4 e o d :i l.- Jr j ,4 .u n [ -. :., t ...4.....).,0 1 \\. l { L' ') -, I j , f'l. ,i f. .j4 I 7-A - 8 t; ,e i,.,l_l _ _ _ _ _ ,s J c. .'N 2 [ h ((t 'l )r^~'
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{ d [ ! ') F L s._4__y> +--7-_--,--{s, g]y, p ..m- 't : a .q): p5 e l F l s 5 ' I! [} l 1 E { r~. __~._41 _j ---l k _.-) ') 3 i tg \\ e s > u,' ; -- -g g v s r. a x i.l il s
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n. g M.. Ai, .a 2 Attachment to RA97/611
Pcthw:y An:ly:Is f r HF Scrubber Liquid Figure 2 I._ f i H h!_! ' 55 Vi t s il L I L ih f ? !d E OlI 6H Q,, \\ ....[.ISc [. k N % \\q, 3 4;r ..s ff hN r Q l f 7 s /g,/ f lc u' / s h \\ / / /,tfY / Yl llll 8 J \\ g, l Et 8 \\ ', }V bb h sa t-h !s el b 3 Attachment to RA97/611
P thway Analycia f:r HF Scrubber Liquid and sampled. When mixing and sampling are in progress, the " day tanks" will t l receive HF produced while the "qualificaHon tanks" are undergoing testing.; After sampi;ng the liquid HF is passed from the qualification tanks to a hold tank which l will have a volume of up to 40,000 liters. In the unlikely event of a process upset I which would raise the uranium concentration in the hold tank above the release limits, then prior to re; ease from the qualification tanks to the hold tank the liquid will either be diverted for later irytroduction into the system or placed into a cont'aner and neutralized. If neutralized, the neutralization may create a solid phase that contains uranium. This solid phase will either be recovered or _ disposed of as low level radioactive waste. The neutralized liquid effluent will be sent to a waste water treatment plant, or if sufficient amounts of uranium cannot be removed from the liquid solidified for disposal as radioactive waste. Planned Acid Handling The HF solution will be collected in a set of favorable geometry ceils, known as day tanks or qualification tanks. The qualification tanks will be sampled prior to ~ transfer to the hold tank to assure ciiticality safety is maintained. The HF solution being produced will not be transferred from the day tanks to the qualification . tanks during the period of sr.mpling ar a transfer. The uranium concentrations in the hold tank will be yerified by taking and analyzing a representative sample of the tank. The representatives of the sample will be ensured by circulating and mixing the solution in the hold tank prior to sampling. If all samples from the qua!ification tanks since the last sampling of the hold tank are lass than the release guidelines, then the hold tank may be released without additional samplingc The hold tank win contain a maximum of 40,000 liters with a maximum - of 20,000 liters leaving the site in any one shipment. Proposed Release Guidelines; i CE will market the HF solution for use as a industrial feed material with uranium concentration less than 3 E-6 Ci/ml, which is equal to the sewer release limit in 10 CFR 20 Appendix B, Each shipment will contain a maximum of 20,000 liters. Many types of analyses may be used to determine uranium concentration some of these methods either measure uranium by mwh (chemical methods) or only certain uranium isotopes (gamma spectroscopy). Conversion of these measurements for comparison to release limits requires knowledge of the uranium isotopic ratios. For this pathway analysis the u,ranium will be assumed to be at the ASTM limits, in actual production, isotopic analysis of every cylinder which enters the conversion process will be known and may be used to calculate specific activities for the uranium in the HF. d 4 Attachment to RA97/61I
- Pathw;y An:lyci3 f:r HF Scrubber Liquid Table 1 provides the specific activities of the uranium isotopes of interest as well as their contribution to the total activity in the HF assuming isotopic ratios at the ASTM limit. The ASTM C996 90 specifications are: 5 0.002 pg U perg 23sU 232 s 10,000 pg zuU perg 23sU 238 s 5,000 pg U per g 2ssU The total uranium concentration, ppm U, for different enrichments has been adjusted to represent the maximum release concentration at 3 E-6 Ci/ml. The density of the liquid was assumed to be 1.1 g/ml. 5 Attachment to RA97/61I l 3
Pcthway Analy;is for HF Scrubber Liquid Table 1 Uranium in HF at Maximum ASTM C996 90 Concentrations U isotope isotope % Specific Activity of Total U % "U concentration by mass Activity isotope per activity per 2 Enrichment (ppm) ( Cl/g) ml of HF mlHF solution (pCifml) as2U 1.00E-08 2.14E+07 1.88E-09 8"U 4.75E-02 6.23E+03 2.61 E-06 5 0.8 8"U 5.00E+00 2.16E+00 9.51E-08 2.99E-06
- U 1.00E-02 6.47E+01 5.7E-09 8"U 9.49E+01 3.36E-01 2.81 E-07 8 'U 1.40E-U8 2.14E+07 1.85E-09 zuU 6.65E-02 6.23E+03 2.55E-06 7
0.56 8"U 7.00E+00 2.16E+00 9.32E-08 2.85E-06 2xU 1.40E-02 6.47E+01 5.58E-09 i 2"U 9.29E+01 3.36E-01 1.92E-07 Pathway Analysis: A pathway analysis was performed to bound the potential exposure to workers at non-licensed facilities handling HF generated by CE. Conservative potential exposures were calculated for conditions where working would be unsafe due to HF concentrations. Internal Exposure Dose estimates have been assessed using conservative but realistic scenario and then extremely conservative assumptions. The calculated dose is less than two orders of magnitude below the exposure limit to the public of 100 mrem / year, which in turn is well below the average background dose of 300 mrem / year from all sources that the average person living in the USA receives. Internal Dose: Inhalation Conservative Assumptions: Combustion Engineering provides 5% of the feed product used per year. The concentration of HF in the solution provided as feed stock by CE is 35% HF by weight. The average HF 6 Attachment to RA97/611
Pathw;y An:lycia f:r HF Scrubber Liquid -concentration in working areas of the plant is 30 ppm, concentration of HF which is immediately dangerous to life or health. 50% of the materialis UO F, Class D, and 50% is UF Class W. Density of HF is 1.15 g/ml. 22 4 Uranium activity in HF solution is 3E-6 pCl/ml. U conc. = Fraction of HF provided by CE x Ratio of liquid to HF x HF concentration in work place x density of air x 1 over the density of HF x Activity of uranium in HF Uconc = 0.05 x
- ("4) x Og(E M-3g(air)
Iml(hq) 3Mp@ 35g(1/F) 1,000,000g(air) ml(air) 1.15g(liq) ml(liq) U onc. = 1.4 E-14 pCi/ml.i, c A worker inhales 2,400 m lyr (2._4 E9 ml/yr) and uranium has an ALI of 2 232 Ci for Class D (stochastic) and 0.7 pCi for Class W (Note: U has a 232 slightly lower All, but the U concentration is orders of magnitude lower than that of the other uranium isotopes).
- ' 1.4 E - 14 Ci Dose (CEDE) = {
x 0.5x + yr ml 2pCi 2.4E9ml 1.4 E - 14pCi 000mrg 0.5x 0.7pCi] x yr ml All Doso(internal) = 0.1 mrem / year i Ingestion: Due to the corrosivity of HF ingestion is not considered a credible pathway. However, the assumption is made that the HF is somehow diluted and used at some future time es a drinking water source. The HF is assumed to be diluted so that the fluoride concentration is 100 times the 1 ppm used by municipal water supplies. With fluoride at 100 ppm, the uranium concentration would be on the order of 1E-11 Ci/ml. If a person were to drink 2 liters a day of this solution everyday of the year, he would receive a dose of approximately 0.001 mrem. External Dese: ' For external doses the alpha and beta components will be absorbed by the aqueous matrix or the protective clothing needed for immersion in the corrosive 7 Attachment to RA97/611 l
Pcthway An: lysis far HF Scrubber Liquid liquid. Therefore only the gamma components of uranium and progeny will be considered in this discussion. The gamma rays from uranium progny were considered up to a half life greater than 100 years. For instance, Th and. 2u"'Pa were considered to be in secular equilibrium with 23eU. The external dose was conservatively calculated assuming total immersion in a liquid solution using the following equation': Dose = 51 (Equation 1) P Where: Uconc.= Uranium (isotope) concentration Pt = the stopping power of tissue relative to water (unity in this case) t = time immersed in days W = average gamma energy in MeV p = density in g/ml (conservatively set to 1) 8 Attachment to RA97/611
Pathw;y An:lyti) frr HF S: rubber Liquid ( Table 2 i External Dose isotope Average Gamma rem / year for mrem / year for Ray Energy (MeV) 5% 7% per disintegration Enrichment - Enrichment "U 1.43E+00 3.21E-02 3.35E-02
- U 1.12E-04 3.67E 3.84E-03 "U
1.42E-01 1.61 E-01 1.69E-01 S U-0.00E+00 0.00E+ 00 .0.00E+00 "U 1.52E-02 5.09E-02 3.72E-02 Total U 2.48E-01 2.43E-01 / The external dose is extremely overestimated because of the assumed conservative uranium concentration and geometry. A person would not be immersed in HF, because of the extreme corrosiveness of HF. Total Effective Dose Equivalent Summing the internal dose resulting from the conservative but realistic inhalation dose of 0.006 mrem and external of 0.2 mrem / year provides a TEDE of 0.2 mrem / year. Summing the extremely conservative inhalation dose of 0.9 mrem and the external dose of 0.2 mrem provides a TEDE of 1.1 mrem / year. A dose of - 1 mrem / year is 2 orders of magnitude less than the ICRP recommendation of 100 mrem a year for a member of the public. Therefore, the release of uranium at 3E-6 Ci/ml does not pose an undue risk to the public or the environment. End Product Usage: CE expects to sell the HF to a chemical manufacture or distributor, for example, Chemtech Products of St. Louis, MO. Conversations with this distributor have identified several potential users for the HF. The most likely use would be for metal pickling which is used in the aerospace and automotive industries. The spent acid in these industries is typically collected, neutralized, and pos 3ibly clarified for metals recovery prior to disposal. CE's industrial grade HF would not be used in any industry contacting the food chain. The Food and Drug Administration currently prohibits the usage of any hydrofluoric acid in food processing, allowing its usage only as a bonding agent for adhesives in food packaging. 9 Attachment to RA97/611
Pathway An. lysis fcr HF Scrubber Liquid
References:
.. Radiation Hygiene Handbook.' Blatz, Hanson, McGraw-Hill Book Company, Inc., New York,1959. l 1 10 Attachment to RA97/611 a
Enclosure to RA97/611 COMBUSTION ENGINEERING,INC. IIEMATITE NUCLEAR FUEL MANUFACTURING FACILITY t REQUEST FOR UNRESTRICTED RELEASE OF HF QUALIFICATION FOR CATEGORICAL EXCLUSION This request for unrestricted release of hydrofluoric acid manufactured as a byproduct of the oxide conversion process for unrestricted commercial use is subject to a categorical exclusion with respect to the need for an environmental assessment in accordance with 10 CFR S t.22(c)(11). To address the specific points of this section: (i) there is no significant change in the types or significant increase in the amounts of any effluents that may be released offsite. As shown in the enclosed pathway analysis for HF scrubber liquid, this request is not expected to result in any significant change in the type of effluents released since the oxide conversion process is not changing. The emission of HF gas to the environment will be reduced due to the increased efficiency of the wet scrubbing process as compared to the present use of the dry scrubbers. (ii) there is no significant increase in individual or cumulative occupational radiation exposure. The wet scrubbing process will not result in a significant change in individual or cumulative occupational radiation exposure during normal operation. Should a contamim.tiori event occur, there will be less potential inhalation exposure from handling the wet scrubber solution than from handling the spent limestone from the present dry scrubbers. (iii) there is no significant construction impact. Construction changes required as a result of the request are minor. A diked pad will be installed south-west of the current dry scrubber in an area formerly used for temporary storage of spent limestone. (iv) there is no significant increase in the potential for or consequences from radiological accidents. The wet scrubbing process does not significantly increase the potential for or consequences from radiological accidents. The radiological and criticality s1fety controls as discussed in the pathway analysis are sufficient to assure the safety of this process.
a; Enclosure to RA97/611 3 COMBUSTION ENGINEERING,INC. IIEMATITE NUCLEAR FUEL MANUFACTURING FACILITY - REQUEST FOR UNRESTRICTED RELEASE OF IIF AFFECTED PAGES Combustion Engineering, Inc., provides a change to the Hematite license application for a request to release hydrofluoric acid manufactured as a byproduct of the oxide conversion process for unrestricted commercial use as described in condition 1.6(h). Added text is denoted by a line in the right margin. The only affected page is listed below: 4 I ist of AfTected Pages Delete Page Add Page Page No. h Date Page No. Een Date 1-7 2 5/29/96 1-7 3 8/12/97
t Safety, and Fire Protection for Fuel Cycle Facilities", Federal flegister, March 21,1989) will be considered during those hazard analyses. Specifically, the following will be included in hazard analyses for equipment important to safety: 1 1. operational parameters important to safety, and limiting specifications for these parameters; 2. documentation of the basis for important-to-safety I requirements for operation; and 3. programs for testing, calibration, and inspection of all instrumentation and control systems important to safety to assure their reliability. (f) (deleted) (g) (deleted) l (h) Combustion Engineering is authorized to release hydrofluoric acid manufactured as a byproduct of the uranium hexafluoride to uranium oxide conversion process for unrestricted commercial use providing the following conditions are met: 1. A representative sample of each batch of hydrofluoric acid product shall be obtained and analyzed for uranium. 2. A batch shall be no larger than 40,000 liters. 3. The specific activity of any batch released for unrestricted use shall be < 3 pCi/ml. License No. SNM-33 Revision 3 Date: 8/12/97 ) Docket No. 70-36 Page: 1-7 1}}