ML20137X697
| ML20137X697 | |
| Person / Time | |
|---|---|
| Issue date: | 09/30/1985 |
| From: | NRC OFFICE OF NUCLEAR REGULATORY RESEARCH (RES) |
| To: | |
| Shared Package | |
| ML20137X702 | List: |
| References | |
| RTR-REGGD-3.063, TASK-ES-401-4, TASK-RE REGGD-03.XXX, REGGD-3.XXX, NUDOCS 8510040579 | |
| Download: ML20137X697 (8) | |
Text
/ %, U.S. NUCLEAR REGULATORY COMMISSION Sp - 1985
!" g 0FFICE OF NUCLEAR REGULATORY RESEARCH b '
Task ES 401-4 g, ORAFT REGULATORY GUIDE Af!D VALUE/ IMPACT STATEMENT
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Contact:
L. Brown (301)427-4628 ONSITE METEOROLOGICAL MEASUREMENT PROGRAM FOR URANIUM REC 0VERY FACILITIES - DATA ACQUISITION AND REPORTING h
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kN A. INTRODUCTION l
Section 40.31, " Applications for Specific Licenses / of 10/CFR Part 40,
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" Dor.estic Licensing of Source Material," requires that' applicants for a license h QV to receive, possess, or use source material in conjune' tion with uranium recovery
%v facilities provide information needed to assist in;%% ~gdemons$ratingthatopera-tions can be conducted to meet the requirements setgorth in 10 CFR Part 40.
S:ction 40.65, "Ef fluent Monitoring Reporting (Requirements," A 9 requires that
%M licensees routinely report radionuclide rel. eases 3to unrestricted areas in liquid
- wj and gaseous effluents. The Uranium Mill Tai' lings Radiation Control Act (UMTRCA) geg s requires the NRC to conform to 40 CFR Part'192, which sets standards for the b if Dcontrolofreleasesfromtailingsrelatedtoproductionoperations, p "
Meteorological conditions infthe vicinity of the facility need to be con-R u sid:: red in the design and operationloffin situ tailings impoundments, the assessment of the potential impact of airborne effluent releases, and the moni-toring of airborne ef fluents. This guide provides guidance acceptable to the 64 NRC staff regarding the feeteorol,ogical parameters that should be measured, the vu s sitingofmeteorological,instguments,systemaccuracies,instrumentmaintenance and servicing schedtdeD.s, ~40d the recovery, reduction, and compilation of data, g
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Any informatjon'hollectionw activities mentioned in this draf t regulatory
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guide are contained'as requirements in 10 CFR Part 40, which provides the regula-xs tory basis for thif b ide. The information collection requirements in 10 CFR Part 40 have been clearea under OMB Clearance No. 3150-0020.
This regulatory guide tad the associated salveilroact statement are baeng issued 6n draft form to involve the ouette in the early stages of the deva toceent of a regulatory oos t t ten in this are s. They have not received comolete staff review and 1o not rtoresent an of ficial 14RC staf f positime l Public conmients are being solicited on both drafts, the guide (including any implementation schedule) and th] value/imoact statement. Co - ts on the value/ impact state **nt should he ucocoanied ov succortino eta. Conaents on both drif ts should be sent to the secretary of the C3veission, u. s. Nuc l ea r 2.qu iito ry Convei ss ion. Washington, D.C. 20555, Attention- O m eting and Service iranen, ny December 2, 1985.
Rrquests *or single cooles of draft quices (.hich say 3 o roduc el) ir for atace.sent 3n an sutsnatic distribution IIst far single cootas of f uture draf t quices in sp*c t fic div es tons s'iould Se saae in writing to the U.S. Nuclear Gequlatory Ccamission, wasnington, D.C 20555. \ttention: Director, Division of Technical Information inq . loc ent Contro l .
F510040579 850930 PDR RECCD 03.XXX R PDR
B. DISCUSSION l
An onsite meteorological measurement program employs instrument systems physically located on or near the site that are capable of measuring meteoro-logical information representative of the site vicinity and that are operated under the authority of the applicant or licensee. The purpose of such a pro-gram at a uranium recovery facility is to provide the meteorological informa-tion needed to make assessments to assist in demonstratine, that the facility design and the conduct of operations are such that relerses of radioactive materials to unrestricted areas can be kept as low as is reasonably achievable.
The information is used (1) for the design and operation of in situ tailings impoundments and (2) for estimating the maximum potential annual radiation dose to the public and the environmental impact resulting from the routine release of radioactive materials in gaseous and particulate effluents.
In situ tailings impoundments need to be designed and operated so that they do not overfill or breach the impoundment restraints, either of which could result in offsite releases. The guidance in the regulatory position assumes that changes in the quantity of liquid in the impoundment are related only to facility operation and to the site precipitation and evaporation {
characteristics.
The maximum potential airborne annual radiation dose to the public and the environmental impact resulting from routine releases is dependent on the l
meteorological characteristics of the site. Wind direction, wind speed, and I 1
atmospheric stability near the site are factors that determine where the efflu-ent will be transported and its concentration. The following guidance applies only to routine releases that occur within 30 meters (100 feet) of the ground.
C. REGULATORY POSITION
- 1. Meteorological Parameters The meteorological parameters reeded for the design and operation of in situ impoundments are precipitation and an indicator of evaporation. The parameters needed tc estimate the atmospheric dispersion of radioactive materials are wind direction, wind speed, and an indication of atmospheric stability. For obtaining an indication of the atmospheric stability, a method 2
such as one of the following (Refs. 1, 2, 3, 4) may be used: insolation--cloud cover and wind speed (Pasquill-Gifford and similar methods), temperature lapse rate method, wind fluctuation method, split-sigma method, or Richardson Number. !
Precipitation and evaporation data should be totaled daily and recorded as monthly and annual summaries.
The basic reduced wind direction, wind speed, and atmospheric stability data should be averaged over a period of 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. At least 15 consecutive minutes of continuous data during each hour should be used to represent a 1-hour average. Wind direction data should be recorded as quarterly and annual wird rose summaries for the 16 compass directions. Quarterly and annual wind l direction, wind speed, and atmospheric stability data should also be compiled I in joint frequency and joint relative frequency (i.e., decimal frequency) form for heights representative of effluent releases. An example of a suitable format for data compilation and reporting purposes is shown in Table 1.
Stability categories should be established to conform as closely as possible with those of Pasquill (Ref. 4).
The minimum amount of meteorological data needed for a siting evaluation is considered to be that amount of data gathered on a continuous basis for a representative consecutive 12-month period. The reduced data and supportive documentation should be retained and should be available for review for the period of facility operation.
- 2. Siting of Meteorological Instruments The location of the meteorological instruments should represent as closely as possible the long-term meteorological characteristics of the area for which the measurements are being made. Whenever possible, the base of the instrument tower or mast should be sited at approximately the same elevation as the facil-ity operation. Ideally, the instruments should be located in an area where localized singular natural or man-made obstructions (e.g., trees, buildings) will have little or no influence on meteorological measurements. Measurements of wind speed, wind direction, and sigma theta (if measured) should be made at least 10 obstruction heights away from the nearest obstruction (Ref. 5). To the extent practicable, these instruments should not be loc ted in the prevail-ing downwind direction of an obstruction. At most facilities, the instruments 3
could all be sited at one location. At some sites, instruments may need to be i
sited at more than one location if the meteorological conditions are not similar throughout the site vicinity. For example, a site could have a milling opera-tion on a mesa where the wind blows predominantly from one direction and a tail-ings impoundment on the plain below in the lee of the mesa where the wind is most frequently from another direction at a lower speed and with an atmospheric stability regime different from that at the release point on the mesa.
Precipitation and evaporation are usually measured near ground level. If an evaporation pan is used to estimate evaporation, a fence or other barrier may be needed to minimize animal intrusion. Parameters such as air tempera-ture, atmospheric moisture, and the pan water temperature should be monitored as appropriate for the type of evaporation model assessment being made.
For atmospheric dispersion assessments, wind speed and wind direction should be monitored at approximately 10 meters (33 feet). For an open lattice tower, instruments should be located on booms oriented into the prevailing wind direction at a minimum distance of two tower widths from the tower to preclude substantial influence of the tower upon measurements (Ref. 5). Sitin0 of the instruments used to estimate atmospheric stability is dependent on the method-ology used. If instrumentation is used to measure incoming solar radiation, it I should be located in an area as free as possible from terrestrial shadows. If the temperature difference with height method is used to estimate the atmos-pheric stability, the lower temperature-difference sensor should be located at the 10-meter level and the upper sensor should be positioned not less than 30 meters (100 feet) above the lower sensor. Aspirated temperature shields should either be poir.ted downward or laterally toward the north.
- 3. System Accuracy and Instrumentation Specifications System accuracy refers to the composite accuracy reflecting the errors introauced by the entire system from the sensor to the data reduction process.
This system ncrmally consists of sensor, cable, signal conditioner, recorders, the humidity and temperature environment for signal conditioning and recording, and the data reduction process. The errors introduced by each of the separate components of the system should be determined by statistical methods (Ref. 6).
The accuracies of all systems should be appropriate to the use to be made of l
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the information over the range of environmental conditions expected to occur during the lifetime of facility operation and should be consistent with the current state of the art for the measurement.
The accuracies for time-averaged values of each parameter should be:
- a. Precipitation: as measured by a recording rain gauge with a resolu-tion of 0.25 mm (0.01 in.). The accuracy of the recorded value should be within 10 percent of the total accumulated catch for amounts in excess of 5 mm (0.2 in.).
Evaporation: consistent with the current state of the art. For b.
information on installation and a description of measurement techniques using an evaporation pan, see Reference 7. An aspirated shielded device such as a lithium chloride or optical dewpoint hygrometer (Ref. 8) is suggested for mea-surement of humidity. Use of a hair hygrometer is not recommended. Tempera-ture sensors should be consistent with the current state of the art for their use.
- c. Wind direction: 15 of azimuth with a starting threshold (the minimum wind speed above which the measuring instrument is performing within I its minimum specification) of less than 0.5 m/s (1.0 mph).
- d. Wind speed: 10.2 m/s (0.5 mph) for speeds less than 2 m/s (5 mph),
10% for speeds between 2 m/s (5 mph) and 22 m/s (50 mph), with a starting threshold of less than 0.5 m/s (1.0 mph).
Parameters not covered above but used to determine atmospheric stability should be measured with accuracies consistent with the current state of the art for measurement of these parameters (Refs. 1, 3).
The recording system for data acquisition may be eithar analog or digital.
l Analog recorders should be of the continuous strip chart recording type.
Digital recorders should sample data at intervals no longer than 60 seconds for wind direction and : peed measurements.
Accuracies for analog records of parameters that nay vary rapidly with time (e.g., wind direction and wind speed) should not be more than 1.5 times those stated above. The system accuracies should include the reduction of data from the strip chart recorder to digital form.
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- 4. System Maintenance, Servicing Schedules, and Data Recovery The systems should be protected against severe environmental conditions j such as blowing sand, lightning, and icing that may occur at the site. Meteoro-logical systems should be inspected at least once every 15 days and serviced at a frequency that will minimize extended periods of outage and ensure an annual data recovery of at least 90% for each individual parameter measured (at least an annual 75% joint data recovery for wind speed, wind direction, and atmospheric stability). The use of redundant sensors and recorders may be an acceptable means of achieving this recovery goal. Systems should be calibrated at least semiannually to ensure that the system accuracies in this guide are met. In areas with high ambient aerosol or particulate loadings in the atmosphere (e.g.,
deserts), calibrations should be performed on a more frequent basis to maintain system accuracies.
Sufficient records should be retained and should be available for review for the period of uranium recovery facili'ty operation to document any activ-ities that may affect the quality of the meteorological data. The records should include operating logs and results of reviews, inspections, maintenance, calibrations, and audits; a description of the types of observations taken l with the results and their acceptability; and actions taken in connection with any deficiencies noted.
D. IMPLEMENTATION The purpose of this section is to provide information to applicants and licensees regarding the NRC staff's plans for using this regulatory guide.
This draft guide has been released to encourage public participation in its develooment. Except in those cases in which an applicant proposes ar acceptacle alternative method for complying with specified portions of the Commission's regulations, the nethods to be described in the final guide reflecting public comments will be used by the NRC staff in evaluating pertinent portions of applications for new uranium recovery facility licenses and for amendments to existing licenses involving major modification of current facilities submitted to the NRC after the final guide has been issued.
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REFERENCES
> 1. International Atomic Energy Agency, " Atmospheric Dispersion in Nuclear Power Plant Siting," Safety Series No. 50-SG-53, Vienna, Austria, 1980.
- 2. S. R. Hanna, G. A. Briggs, et al., "AMS Workshop on Stability Classifica-tion Schemes and Sigma Curves--Summary and Recommendations," Bulletin of American Meteorological Society, Vol. 58, No. 12, p. 1305-1309, December 1977.
- 3. American Nuclear Society, "American National Standard for Determining Meteorological Information At Nuclear Power Sites," ANSI /ANS-2.5-1984, 1984.
- 4. F. Pasquill, "The Estimation of Windborne Material," Meteorological Magazine, Vol. 90, pp. 33-49, 1961.
- 5. R. C. Hilfiker, " Exposure of Instruments," in Air Pollution Meteorology, USEPA Air Pollution Training Institute, Research Triangle Park, North Carolina, September 1975.
- 6. C. E. P. Brooks and N. Carruthers, Handbook of Statistical Methods in Meteorology, M.0. 538, Chapter 5, Her Majesty's Stationery Office, London, 1953.
- 7. U.S. Department of Commerce, Substation Observations, Weather Service Observing Handbook No. 2, Chapter 5, 1972.
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- 8. L. J. Fritschen and L. W. Gay, Environmental Instrumentation, Chapter 6, Springer-Verlag, New York, 1979.
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TABLE 1 PERIOD OF RECORD:
I PASQUILL STABILITY CATEGORY Wind Speed at 10-m Level Wind 0.22-1.7 1.8-3.5 3.6-5.8 5.9-8.5 8.6-11.1 >11.2 m/s Direction (0.5-3.9) (4.0-7.9) (8.0-12.9) (13.0-18.9) (19.0-24.9) [(25)(mph) Total N
NNE NE ENE E
WNW NW NNW Total Number of Calms
- Number of Invalid Hours Number of Valid Hours
- A calm is any average wind speed below the starting threshold of the wind speed or direction sensor, whichever is greater. Calms should be included in the table above by assigning to each calm a wind speed that is equal to the starting threshold of the wind speed or direction sensor, whichever is greater. Wind direction during calm conditions should be assigned in proportion to the directional distribution of noncalm winds in the lowest noncalm wind speed category. The directional distribution of l calms should then be included in the lowest noncelm wind speed category.
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