Radiological Environmental Monitoring Program Requirements - Enclosing Branch Technical Position, Revision 1 (Generic Letter 79-65)
November 27, 1979
ALL POWER REACTOR LICENSEES
The NRC staff has recently completed a review of Radiological Environmental
Monitoring Program Requirements and has revised the portion of the Branch
Technical Position (BTP) concerning direct radiation measurements. A copy of
the BTP (Revision 1, November 1979) is attached for your use and
information. These revised requirements will be implemented in the licensing
review of OL applicants and in the Radiological Effluent Technical
Specification 46 (RETS) update for conformance to the provisions of 10 CFR
50, Appendix I review for licensees.
For those facilities which have submitted RETS applications, it is not
necessary to supplement those submittals at this time, since the necessary
changes will be made during the staff's review of your application. For
those facilities which have not submitted a RETS application, these revised
requirements should be incorporated into the guidance provided by letter
dated July 18, 1979 and a complete application made within 30 days of your
receipt of this letter.
If you have any questions, please contact us.
William P. Gammill, Acting Assistant
Director for Operating Reactor Projects
Division of Operating Reactors
Branch Technical Position,
Branch Technical Position
Regulatory Guide 4, Environmental Technical Specifications for Nuclear Power
Plants, issued for comment in December 1975, is being revised based on
comments received. The Radiological Assessment Branch issued a Branch issued
a Branch Position on the radiological portion of the environmental
monitoring program in March, 1978. The position was formulated by an NRC
working group which considered comments received after the issuance of the
Regulatory Guide 4.8. This is Revision 1 of that Branch Position paper. The
changes are marked by a vertical line in the right margin. The most
significant change is the increase in direct radiation measurement stations.
10 CFR Parts 20 and 50 require that radiological environmental monitoring
programs be established to provide data on measurable levels of radiation
and radioactive materials in the site environs. In addition, Appendix I to
10 CFR Part 50 requires that the relationship between quantities of
radioactive material released in effluents during normal operation,
including anticipated operational occurrences, and resultant radiation doses
to individuals from principals pathways of exposure be evaluated. These
programs should be conducted to verify the effectiveness of in-plant
measures used for controlling the release of radioactive materials.
Surveillance should be established to identify changes in the use of
unrestricted areas (e.g., for agricultural purposes) to provide a basis for
modifications in the monitoring programs for evaluating doses to individuals
from principal pathways of exposure. NRC Regulatory Guide 4.1, Rev. 1,
"Programs for Monitoring Radioactivity in the Environs of Nuclear Power
Plants," provides an acceptable basis for the design of programs to monitor
levels of radiation and radioactivity in the station environs.
This position sets forth an example of an acceptable minimum radiological
monitoring program. Local site characteristics must be examined to determine
if pathways not covered by this guide may significantly contribute to an
individual's dose and should be included in the sampling program.
AN ACCEPTABLE RADIOLOGICAL
ENVIRONMENTAL MONITORING PROGRAM
Environmental samples shall be collected and analyzed according to Table 1
at locations shown in Figure 1.1 Analytical techniques used shall be such
that the detection capabilities in Table 2 are achieved.
The results of the radiological environmental monitoring are intended to
supplement the results of the radiological effluent monitoring by verifying
that the measurable concentrations of radioactive materials and levels of
radiation are not higher than expected on the basis of the effluent
measurements and modeling of the environmental exposure pathways. Thus, the
specified environmental monitoring program provides measurements of
radiation and of radioactive materials in those exposure pathways and for
those radionuclides which lead to the highest potential radiation exposures
of individuals resulting from the station operation. The initial
radiological environmental monitoring program should be conducted for the
first three years of commercial operation (or other period corresponding to
a maximum burnup in the initial core cycle). Following this period, program
changes may be proposed based on operational experience.
The specified detection capabilities are state-of-the-art for routine
environmental measurements in industrial laboratories.
Deviations are permitted from the required sampling schedule if specimens
are unobtainable due to hazardous conditions, seasonal unavailability,
malfunction of automatic sampling equipment and other legitimate reasons. If
specimens are unobtainable due to sampling equipment malfunction, every
effort shall be made to complete corrective action prior to the end of the
next sampling period. All deviations from the sampling schedule shall be
documented in the annual report.
The laboratories of the licensee and licensee's contractors which perform
analyses shall participate in the Environmental Protection Agency's (EPA's)
Environmental Radioactivity Laboratory Intercomparisons Studies (Crosscheck)
Program or equivalent program. This participation shall include all of the
determinations (sample medium-radionuclide combination) that are offered by
EPA and that also are included in the monitoring program. The results of
analysis of these crosscheck samples shall be included in the annual report.
The participants in the EPA crosscheck program may provide their EPA program
code so that the NRC can review the EPA's participant data directly in lieu
of submission in the annual report.
1 It may be necessary to require special studies on a case-by-case and
site specific basis to establish the relationship between quantities of
radioactive material released in effluents, the concentrations in
environmental media, and the resultant doses for important pathways.
If the results of a determination in the EPA crosscheck program (or
equivalent program) are outside the specified control limits, the laboratory
shall investigate the cause of the problem and take steps to correct it.
The results of this investigation and corrective action shall be included in
the annual report.
The requirement for the participation in the EPA crosscheck program, or
similar program, is based on the need for independent checks on the
precision and accuracy of the measurements of radioactive material in
environmental sample matrices as part of the quality assurance program for
environmental monitoring in order to demonstrate that the results are
A census shall be conducted annually during the growing season to determine
the location of the nearest milk animal and nearest garden grater than 50
square meters (500 sq. ft.) producing broad leaf vegetation in each of the
16 meteorological sectors within a distance of 8 km (5 miles).2 For
elevated releases as defined in Regulatory Guide 1.111, Rev. 1., the census
shall also identify the locations of all milk animals, and gardens greater
than 50 square meters producing broad leaf vegetation out to a distance of 5
km. (3 miles) for each radial sector.
If it is learned from this census that the milk animals or gardens are
present at a location which yields a calculated thyroid dose greater than
those previously sampled, or if the census results in changes in the
location used in the radioactive effluent technical specifications for dose
calculations, a written report shall be submitted to the Director of
Operating Reactors, NRR (with a copy to the Director of the NRC Regional
Office) within 30 days identifying the new location (distance and
direction). Milk animal or garden locations resulting in higher calculated
doses shall be added to the surveillance program as soon as practicable.
The sampling location (excluding the control sample location) having the
lowest calculated dose may then be dropped from the surveillance program at
the end of the grazing or growing season during which the census was
conducted. Any location from which milk can no longer be obtained may be
dropped from the surveillance program after notifying the NRC in writing
that they are no longer obtainable at that location. The results of the
land-use census shall be reported in the annual report.
The census of milk animals and gardens producing broad leaf vegetation is
based on the requirement in Appendix I of 10 CFR Part 50 to "Identify
changes in the use of unrestricted areas (e.g., for agricultural purposes)
to permit modifications in monitoring programs for evaluating doses to
individuals from principal pathways of exposure." The consumption of milk
from animals grazing on contaminated pasture and of leafy vegetation
contaminated by airborne
2 Broad leaf vegetation sampling may be performed at the site boundary in
a sector with the highest D/Q in lieu of the garden census.
radioiodine is a major potential source of exposure. Samples from milk
animals are considered a better indicator of radioiodine in the environment
than vegetation. If the census reveals milk animals are not present or are
unavailable for sampling, then vegetation must be sampled.
The 50 square meter garden, considering 20% used for growing broad leaf
vegetation (i.e., similar to lettuce and cabbage), and a vegetation yield of
2 kg/m2, will produce the 26 kg/yr assumed in Regulatory Guide 1.109, Rev
1., for child consumption of leafy vegetation. The option to consider the
garden to be broad leaf vegetation at the site boundary in a sector with the
highest D/Q should be conservative and that location may be used to
calculate doses due to radioactive effluent releases in place of the actual
locations which would be determined by the census. This option does not
apply to plants with elevated releases as defined in Regulatory Guide 1.111,
The increase in the number of direct radiation stations is to better
characterize the individual exposure (mrem) and population exposure
(man-rem) in accordance with Criterion 64 - Monitoring radioactivity
releases, of 10 CFR Part 50, Appendix a. The NRC will place a similar
amount of stations in the area between the two rings designated in Table 1.
A. Annual Environmental Operating Report, Part B, Radiological.
A report on the radiological environmental surveillance program for the
previous calendar year shall be submitted to the Director of the NRC
Regional Office (with a copy to the Director, Office of Nuclear REactor
Regulation) as a separate document by May 1 of each year. the period
of the first report shall begin with the date of initial criticality.
The reports shall include a summary (formate of Table 3),
interpretations, and an analysis of trends for the results of the
radiological environmental surveillance activities for the report
period, including a comparison with operational controls,
preoperational studies (as appropriate), and previous environmental
surveillance reports and an assessment of the observed impacts of the
station operation on the environment.
In the event that some results are not available the report shall be
submitted noting and explaining the reasons for the missing results.
the missing data shall be submitted as soon as possible in a
The reports shall also include the following: a summary description of
the radiological environmental monitoring program; a map of all
sampling locations keyed to a table giving distances and directions
from one reactor; the results o land use censuses; and the results of
licensee participation in a laboratory crosscheck program if not
participating in the EPA crosscheck program.
B. Nonroutine Radiological Environmental Operating Report
"If a confirmed3 measured radionuclide concentration in an
environmental sampling medium averaged over any quarter sampling period
exceeds the reporting level given in Table 4, a written report shall be
submitted to the Director of NRC Regional Office (with a copy to the
Director, Office of Nuclear Reactor Regulation) within 30 days from the
end of the quarter. If it can be demonstrated that the level is not a
result of plant effluents (i.e., by comparison with control station or
preoperational data) a report need not be submitted, but an explanation
shall be given in the annual report. When more than one of the
radionuclides in Table 4 are detected in the medium, the reporting
level shall have been exceeded if:
concentration (1)/reporting level (1) +
concentration (2)/reporting level (2) + ... > or = 1
If radionuclides other than those in Table 4 are detected and are due
from plant effluents, a reporting level is exceeded if the potential
annual dose to an individual is equal to or greater than the design
objective doses of 10 CFR Part 50, Appendix I. This report shall
include an evaluation of any release conditions, environmental factors,
or other aspects necessary to explain the anomalous result.
3 A confirmatory reanalysis of the original, a duplicate, or a new sample
may be desirable, as appropriate. The results of the confirmatory
analysis shall be completed at the earliest time consistent with the
analysis, but in any case within 30 days.
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