Contents Chapter 4
Acronyms M. A. Bogle, M. L. Coffey, K. G. Hanzelka, J. F. Hughes, H. B. McElhoe, I. D. Shelton, and M. M. Stevens
Annual environmental surveillance is a major activity on the ORR. Environmental surveillance consists of the collection and analysis of samples of air, water, soil, foodstuffs, biota, and other media from the reservation and its surroundings. External radiation is also measured. Samples are analyzed for chemical content and for the presence of radioisotopes. Data collected from environmental surveillance activities are used to demonstrate compliance with applicable standards, to assess exposures to members of the public, and to assess effects (if any) on the local population, and the environment.
Seven meteorological towers provide data on meteorological conditions and on the transport and diffusion qualities of the atmosphere on the ORR. Data collected at the towers are used in routine dispersion modeling to predict impacts from facility operations and as input to emergency response atmospheric models used in the event of accidental releases from a facility. Data from the towers are also used to support various research and engineering projects.
5.1.1 Description
The seven meteorological towers, depicted in Fig. 5.1, consist of one 330-ft (100-m) tower (MT5) and one 200-ft (60-m) tower
(MT6) at the Y-12 Plant, one 330-ft tower (MT2) and two
100-ft towers (MT3 and MT4) at
ORNL, and one 200-ft tower
(MT1) and one 100-ft (MT7) tower at the K-25 Site.
Data are collected at different levels to determine the vertical structure of the atmosphere and the possible effects of vertical variations on releases from facilities. At all towers, data are collected at 32.8 ft and at the top of the tower. At the 330-ft towers, data are collected at an intermediate 100-ft level as well. At each measuring level on each tower, temperature, wind speed, and wind direction are measured. Humidity and data needed to determine atmospheric stability (a measure of the dispersive capability of the atmosphere) are also measured at each tower. Barometric pressure is measured at one tower at each facility. Precipitation is measured at MT1 and MT7 at the K-25 Site and at MT2 at ORNL; solar radiation is measured at MT2.
Data from the towers at each site are collected by a dedicated control computer at that site. The towers are polled, and the data are filed on disk. Fifteen-minute and hourly values are stored at each site for a running 24-hour period, but only hourly data are routinely stored beyond 24 hours. The meteorological monitoring data from all towers are summarized quarterly at the Y-12 Plant and monthly at ORNL and the K-25 Site. Quarterly calibration of the instruments is conducted for each site by an outside contractor.
Fifteen-minute and hourly data are used directly at each site computer for emergency-response purposes such as input to dispersion models. Annual dose estimates are calculated from archived data (either hourly values or summary tables of atmospheric conditions). Data quality is checked continuously against predetermined data constraints, and out-of-range parameters are marked invalid and are not input to the dispersion models.
5.1.2 Results
Prevailing winds are generally up-valley from the southwest and
west-southwest or down-valley from the northeast and east-northeast.
This pattern is the result of the channeling effect of the ridges
flanking the site. Winds in the valleys tend to follow the ridges, with
limited cross-ridge flow. These conditions are dominant over the entire
reservation, with the exception of the K-25 Site, which is located
in a relatively open area that has a more varied flow. Weaker valley
flows are noted in this area, particularly in locations near the Clinch
River.
On the reservation, low-speed winds predominate at the surface level. This characteristic is noted at all tower locations, as is the increase in wind speed at the height at which measurements are made. This activity is typical of tower locations and is important when selecting appropriate data for input to dispersion studies.
The atmosphere over the reservation is dominated by stable conditions on most nights and in early morning hours. These conditions, coupled with the low wind speeds and channeling effects of the valleys, result in poor dilution of material emitted from the facilities. These features are captured in the data input to the dispersion models and are reflected in the modeling studies conducted for each facility.
Precipitation data from tower MT2 are used in stream-flow modeling and in certain research efforts. The data indicate the variability of regional precipitation: the high winter rainfall amounts resulting from frontal storms and the uneven, but occasionally intense, summer rainfall associated with thunderstorms.
The average data capture efficiency (a measure of acceptable data) across all locations and at the 16 tower levels was 98.3% in 1995. The maximum capture efficiency was 99.9% at Y-12 MTW at 60 m, and the minimum capture efficiency was 97% at ORNL MT3 at 10 m.
5.2 EXTERNAL GAMMA RADIATION MONITORING
External gamma radiation measurements are made to determine whether routine radioactive effluents from the ORR are increasing external radiation levels significantly above normal background levels.
5.2.1 Sample Collection and Analytical Procedures
External gamma measurements are recorded weekly at six ambient air
stations (Fig. 5.2). In addition, measurements were collected at the American Museum of
Science and Energy (Station 41).
5.2.2 Results
Table 5.1
presents the following data for individual stations: number of
measurements, maximum value, minimum value, average value, and standard
error of the mean. The median value for the ORR in 1995 was
7.6 �R/hour, while the median value for cities in the United States
during 1989 was 9.3 �R/hour
(EPA 1990
). Any contribution to the external gamma signature by the
DOE facilities is not
distinguishable at the ORR perimeter air monitoring station
(PAM) locations.
In addition to stack monitoring conducted at the DOE Oak Ridge installations, ambient air monitoring is performed to measure radiological and other selected parameters directly in the ambient air adjacent to the facilities. Ambient air monitoring provides direct measurement of airborne concentrations of radionuclides and other hazardous pollutants in the environment surrounding the facilities, allows facility personnel to determine the relative level of contaminants at the monitoring locations during an emergency, verifies that the contributions of fugitive and diffuse sources are insignificant, and serves as a check on dose-modeling calculations.
The following sections discuss the ambient air monitoring networks for the ORR, the Y-12 Plant, ORNL, and the K-25 Site.
5.3.1 ORR Ambient Air Monitoring
The objectives of the ORR ambient air monitoring program are (1) to
perform surveillance of airborne radionuclides at the reservation
perimeter and (2) to collect reference data from remote locations.
The ORR PAM network associated
with objective 1 includes stations 35, 37, 38, 39, 40, 42, 46, and
48 (Fig. 5.3); the remote air monitoring
(RAM) network (objective 2)
consists of stations 51 (Norris Dam) and 52 (Fort Loudoun Dam). Sampling
was conducted at each ORR station to quantify levels of alpha-, beta-,
and gamma-emitting radionuclides, tritium, beryllium, and total
radioactive strontium during 1995.
Atmospheric dispersion modeling was used to select appropriate sampler locations. The locations selected are those most likely to be affected by routine releases from the Oak Ridge facilities. Therefore, it is predicted that no residence or business in the vicinity of the ORR would be affected by undetected releases of radioactive materials. To provide an estimate of background radionuclide concentrations, two additional stations are located at sites not affected by releases from the ORR.
The sampling system consists of two separate instruments. The particulates are captured using a high-volume air sampler on glass fiber filters. The filters are collected weekly, composited every 4 weeks, then submitted to the laboratory for isotopic analysis. The second system is designed to collect tritiated water vapor. The sampler consists of a prefilter followed by an adsorbent trap consisting of indicating silica gel. The samples are collected weekly, composited monthly, then submitted to the laboratory for tritium analysis.
The ORR ambient air network (Fig. 5.3) provides appropriate monitoring for all facilities within the reservation, which eliminates the necessity for site-specific programs ambient air programs. As part of the ORR network, an ambient air monitoring station located in the Scarboro Community of Oak Ridge (Station 46) measures off-site impacts of Y-12 Plant operation, and is located near the theoretical area of maximum public pollutant concentrations as calculated by air-quality modeling. Station 40 of the ORR network monitors the east end of the Y-12 Plant, and Station 37 monitors the overlap of Y-12 Plant, ORNL, and K-25 Site emissions.
Table 5.4
represents the average concentration of three isotopes of uranium at
each station for sampling years 1992, 1993, 1994, and 1995.
With agreement from TDEC personnel, the ambient air sampling program at
the Y-12 Plant has been significantly reduced, effective at the end
of 1994. All fluoride, total suspended particulates
(TSP), and particulate matter
less than 10 microns in diameter
(PM10) sampling has been
discontinued, and all but 3 of the 12 uranium samplers have been
shut down. The mercury sampling program will continue to monitor ambient
air level concentrations as a result of remediation and decommissioning
and decontamination activities.
The following types of ambient air monitoring systems were operated by
the Y-12 Plant in 1995:
The locations of these monitoring stations are shown in Fig. 5.4.
Four outdoor ambient mercury monitoring stations (stations on the east
and west ends of the plant and two stations near Building 9201-4)
were established on-site in 1986 and are still being monitored. An
additional site was added at New Hope Pond in August 1987 and monitored
while the pond was being closed and capped (1987-89). In February 1988,
a control or reference site was established at Rain Gage No. 2 on
Chestnut Ridge in the Walker Branch Watershed. This reference site was
discontinued after collecting data for approximately 20 months to
establish background concentrations and a seasonal pattern. Data for the
New Hope Pond and Rain Gage No. 2 sites have been presented in earlier
ORR environmental reports. In late 1995, an additional site was
established at SWHISS House
9422-13 south and west of the old site near Building 9404-13.
Because no established or EPA-approved methods for measuring mercury
vapor in ambient air existed when the program was initiated, staff of
the ORNL Environmental Sciences Division developed a method to meet the
needs of the monitoring program for the Y-12 Plant. At each of the
monitoring sites, airborne mercury vapor is adsorbed onto iodated
charcoal by pulling air through a Teflon filter, a flow-limiting
orifice, and a glass sampling tube packed with the iodated charcoal. The
charcoal sampling tubes are routinely changed every 7 days. Average air
concentration of mercury vapor for each sampling period is calculated by
dividing the total quantity of mercury collected on the charcoal by the
total volume of air pulled through the tube.
Table 5.6
presents mercury monitoring data for 1995, data from the 1986 through
1988 period, and data from the reference or control site. Figure 5.5 shows the trends in mercury concentrations for the four active ambient
air mercury monitoring sites since the inception of the program in
1986.
With few exceptions, annual average mercury vapor concentrations have
been lower in recent years than concentrations measured during the early
years of the monitoring program (1986 through 1988). This trend
continues through 1995 (see Table 5.6). All four of the monitoring sites recorded significantly lower annual
averages (Student's t
-test at the 1% level) for mercury-vapor concentration than the
1986 through 1988 average. With the exception of the site at
Building 9404-13, 1995 averages for all sites are lower, though not
significantly, than those recorded for 1994. The general decrease in
ambient mercury recorded at the Y-12 sites since 1989 is thought to
be related to the reduction in coal burned at the Y-12 Steam Plant
beginning in 1989 and to the completion prior to 1989 of several major
engineering projects (e.g., New Hope Pond closure, the Perimeter
Intrusion Detection Assessment System
(PIDAS),
RMPE, and Utility Systems
Restoration) that may have caused a temporary increase in mercury air
concentrations due to disturbances to contaminated soil and sediment.
The seasonal pattern of higher mercury vapor concentrations during the
warmer months of the year continued through 1995 (see Fig. 5.5 ).
In 1995, though, ambient mercury concentrations at the two monitoring
sites near Bldg. 9201-4 were elevated above natural background.
Results indicate that the concentrations of mercury vapor are well below
the NESHAP guideline of 1 �g/m3 (30-d average) and
the American Conference of Governmental Industrial Hygienists
(ACGIH) threshold limit
value of 50 �g/m3 (time weighted average for 8-hour
workday and 40-hour work week). The maximum weekly concentration
measured in 1995 (0.389 �g/m3 at Building 9404-13)
is less than 1% of the ACGIH limit for a 40-hour work week. Average
concentrations at the monitoring sites located at the east and west end
of the Y-12 Plant are as low as levels measured at our reference
site on Chestnut Ridge.
In late 1995, Tekrantm Model 2537A mercury vapor
analyzers were installed at Ambient Station No. 8 and SWHISS House
9422-13 located southwest of the Building 9404-13 site. These new
monitors are self-calibrating, include mass flow controllers, and can
provide almost continuous analysis of mercury vapor in air at
sub-ng/cm3 levels at time intervals as short as
10 minutes. Plans are for two additional Tekran analyzers to be
installed at Ambient Station No. 2 and a not yet determined
location near the present monitoring site at Building 9805-1. The
new monitors are presently being run simultaneously with the existing
monitoring system (i.e., the iodated charcoal traps) to verify
comparability of the measurements. As the reliability and comparability
of data of the Tekrans is established, the use of the iodated charcoal
traps will be phased out. The monitors provide data on demand and,
because of their high sensitivity, are averaged over much shorter time
intervals than the charcoal tube data (i.e., minutes instead of days).
When combined with synoptic meteorologic data (wind speed and
direction), the data generated by this new monitoring system can be used
to better understand the nature and location of fugitive mercury vapor
sources at the Y-12 Plant. Preliminary analysis of the data
collected at the two existing Tekran sites shows a strong correlation
between wind direction and mercury-vapor concentration with
significantly higher mercury-vapor concentrations measured at both sites
when the prevailing wind direction is from the east and north.
The sampling system consists of a low-volume air sampler for particulate
collection using a 47-mm glass fiber filter. The filters are
collected biweekly, composited annually, then submitted to the
laboratory for isotopic analysis. Following the filter is a charcoal
cartridge used to collect adsorbable gases (e.g., iodine). In 1995,
tritium monitoring was initiated at ORNL Stations 1 and 2 and
continued at Stations 3 and 7. A silica gel column is used for
the collection of tritium as tritiated water. The samples are collected
biweekly. The silica gel is composited monthly, then submitted to the
laboratory for tritium analysis. The charcoal cartridges are analyzed
biweekly using gamma spectroscopy for adsorbable gas quantification.
The ambient air program sampling schedule and monitoring capabilities
for airborne particulate matter, uranium, and metals are listed in
Table 5.8.
All parameters are chosen with consideration of existing and proposed
regulations and the level and type of operations in and around the
K-25 Site. Changes in emissions, wind profile, site activities, or
any other parameter that may alter the potential impact of
K-25 Site activities on the environment or community may warrant
periodic changes of pollutants measured, number of stations, or
relocation of existing stations.
During this reporting period, the network was reevaluated with respect
to K-25 Site operations. Because of the scheduled facility
demolition outside of the current perimeter monitoring network, a
temporary station (K7) was activated in March 1995. Following the
conclusion of major portions of the demolition activities, a systematic
monitoring network change was initiated in December 1995 with the
shut down of HV sampling at Stations K4, K5, and K7.
Station K4 was identified as redundant to the prevailing downwind
monitoring of the K-25 Site. Station K7 was designated as a major
demolition project monitoring network. Stations for the K-700 Powerhouse
complex and Station K5 were similarly designated for the Cooling
Tower demolition project. These stations and their operations were no
longer needed because demolition of the major facilities was nearly
complete. These changes were initiated only after review and concurrence
by DOE and TDEC.
TSP 24-hour results for Stations K1 and K7 have been analyzed for
impact of the K-700 complex demolition project on the local air quality.
TSP concentrations ranged from a low of 6.1 to 99.4 �g/m3.
Station K7 demonstrated the highest 24-hour result. TSP results for
Stations K5 and K6 have been identified to measure any impact of
the K-861/K-892 cooling tower structures demolition project on the local
air quality. TSP concentrations ranged from a low of 7.8 to 79.6
�g/m3. Station K6 demonstrated the highest 24-hour result.
Results did not indicate a measurable TSP contribution that could be
attributed directly to either demolition project. No TSP concentration
levels of environmental concern were measured.
Annual TSP geometric averages of 24-hour measurements are presented in
Table 5.9. TSP is no longer regulated; however, data are compared with previous
Tennessee and national primary and secondary standards. The annual TSP
results range from a low of 24.3 to 47.7 �g/m3. The
highest average TSP value was only 63.6% and 79.5% of the
previous annual primary and secondary standards, respectively.
Historical data shows that these levels are typical for this period of
the year. Annual results from stations identified to measure the impact
of demolition activities did not indicate a measurable TSP contribution
that could be directly attributed to either project. No TSP
concentration levels of environmental concern were measured (see
Fig. 5.8 for 5-year TSP trend).
Daily PM10 analyses were performed on all 24-hour samples. A summary of
all PM10 measurements is presented in Table 5.10.
For 1995, the 24-hour PM10 concentrations ranged from 6.4 to
51.9 �g/m3. The highest measured value was 34.6% of
the Tennessee 24-hour primary and secondary standards (i.e.,
150 �g/m3). These levels are not an environmental
concern.
Annual PM10 arithmetic averages of 24-hour measurements are presented in
Table 5.10. The averaged PM10 annual result was 23.3 �g/m3. This
value was only 46.6% of the Tennessee and national annual primary
and secondary standards for PM10 (i.e., 50 �g/m3).
Historical data shows that this level is typical of measurements during
this period of the year; it is of no environmental concern (see
Fig. 5.9 for 5-year PM10 trend).
Quarterly lead results were determined from analyses of monthly
composites of 24-hour samples for each station. The total masses of lead
were determined by the inductively coupled plasma mass spectrometry
(ICP-MS) analytical
technique. This technique was initiated in 1993, replacing a graphite
furnace atomic absorption method (thus simplifying all metals analyses
to one method). A summary of lead measurement results are presented in
Table 5.11
and compared against the Tennessee and national quarterly standard of
1.5 �g/m3. There are no 24-hour ambient or monthly ambient
air criteria pollutant standards for lead. The maximum quarterly lead
result was 0.0029 �g/m3. This value was only
0.19% of the quarterly standard for lead. Quarterly summaries from
Stations K1, K5, K6, and K7 were identified to measure the impact
of demolition activities. These results did not indicate a measurable
lead contribution that could be directly attributed to either project.
No lead concentration levels of environmental concern were measured (see
Fig. 5.10 for 5-year lead trend).
Stations K1, K3, K5, K6, and K7 were identified to measure the impact of
demolition activities. Measured levels of arsenic and chromium at
stations sensitive to the cooling tower demolition project were above
typical levels during this reporting period. These measurements were
isolated to Stations K5 and, to a lesser extent, K3, which are in
the prevailing downwind direction from the cooling tower demolition
areas at the K-25 Site. Building materials were known to have been
treated or exposed to arsenic and chromium compounds.
Water quality measurements serve as guides to the general health of the
environment. The sampling and analysis in this program are conducted in
addition to requirements mandated in
NPDES permits for individual
ORR DOE facilities. Although there is some overlap of sampling sites in
the NPDES and environmental monitoring plan programs, frequency and
analytical parameters vary.
Sampling frequency under the environmental monitoring plan is bimonthly,
with half of the sites being sampled one month and the other half in the
following month. Grab samples are collected and analyzed for general
water quality parameters, total metals, and volatile organics. They are
also screened for radioactivity and analyzed for specific radionuclides
when appropriate.
In 1994 the collection of semiannual composite samples from WOC at White
Oak Dam (WCK 1.0) and the Clinch River downstream from all DOE
inputs (CRK 16) was implemented. These samples are analyzed for
isotopic uraniums, thoriums, and transuranics.
Most of these locations are classified by Tennessee for certain uses,
for example, domestic water supplies or recreational use. Tennessee
water quality criteria for domestic water supplies, for freshwater fish
and aquatic life, and for recreation (water and organisms), are used as
references for locations where they are applicable. Out of the
79 parameters analyzed for at each of the 22 locations,
chromium at White Oak Dam (WCK 1.0), arsenic and mercury at the
Melton Hill Reservoir at the Oak Ridge Marina (CRK 80), and arsenic
at the water supply intake for Knox County (CRK 58) are the only
parameters that exceeded a reference value in 1995. Of these, chromium
at White Oak Dam has been historically detected at elevated levels.
The Tennessee water quality criteria do not include criteria for
radionuclides. Radionuclides were detected (statistically significant at
a 95% confidence interval) at all of these surface water locations
in 1995. The following observations are made from examining three years
of historic data. Bear Creek downstream from the Y-12 Plant Burial
Grounds (BCK 9.4) has consistently had the highest levels of gross
alpha activity and, associated with the alpha activity, total uranium
and uranium isotopes. BCK 9.4 also has elevated levels of gross
beta activity. The highest levels of gross beta, total rad strontium,
and tritium have been at Melton Branch downstream from ORNL
(MEK 0.2), White Oak Creek at White Oak Dam (WCK 1.0) and
White Oak Creek downstream from ORNL (WCK 2.6). These data are
consistent with the processes or legacy activities nearby or upstream
from these locations. The results for the semiannual composites at
CRK 16 and WCK 1.0 are consistent with the bimonthly samples
collected from these locations.
The water quality monitoring is done as a best management practice. In
some instances the water quality criteria are below the reported
analytical detection limits (examples are mercury, selenium, and
silver). On some occasions, interferences with the analytical
instrumentation, such as high levels of suspended solids after a
rainfall, may result in a laboratory reporting a detection limit that is
higher than normal and above a water quality criterion. This monitoring
serves as a record of water quality criteria and provides an informal
comparison. Of all the parameters measured in the surface water as a
best management practice, mercury is the only demonstrated contaminant
of concern. Continued reductions of mercury in plant effluent and
monitoring for mercury discharge at Station 17 is a requirement of
the new NPDES permit.
Radiological data are compared with
DCGs published in DOE
Order 5400.5. The DCG for water is the concentration of a given
radionuclide that, if the water were ingested at the rate of
730 L/year, would result in an
EDE of 100 mrem/year to
``reference man,'' as defined by
ICRP Publication 23.
Radiological data are reported as percentages of the DCGs for given
radionuclides. If the sum of DCG percentages for a location ever exceeds
100%, an analysis of the best available technology to reduce the sum of
the percentages of the radionuclide concentrations to their respective
DCGs to less than 100%would be required as specified in DOE
Order 5400.5.
Station 17, located near the junction of Bear Creek and Scarboro
roads, is used to monitor EFPC downstream of Lake Reality but prior to
its leaving the easternmost Y-12 Plant boundary (Fig. 5.13). Discharges from Y-12 Plant processes affect water quality and
flow in EFPC before it enters the Clinch River. Samples were obtained
for radiological and nonradiological parameters and grab samples for
mercury and volatile organics were obtained daily at Station 17.
With the exception of holidays, 24-hour composite samples were obtained
every day of the week; a 72-hour composite was collected on weekends for
a variety of chemical parameters.
More than 200 samples were collected in 1995 at Station 17 for
analysis of nonradiological parameters, resulting in more than 15,000
measurements. Comparisons with Tennessee water quality criteria, for
parameters where there was an exceedence, are shown in Table 5.14.
All 246 measurements for silver, arsenic, selenium, cadmium, and zinc
were above those criteria because the detection limits of the analytical
method are above the water quality criteria (see Table 5.14). Of the remaining measurements, some measurements for copper and
mercury exceeded the criteria. On eleven occasions the measured value
for copper exceeded the water quality criteria.
Mercury data are used for long- and short-term trending of mercury
concentrations in plant effluents. The legacy of contamination resulting
from the use and storage of mercury at the Y-12 Plant has been
previously acknowledged and has prompted a series of remedial measures.
In the late 1950s, the average annual concentration of mercury in EFPC
peaked at about 2.3 mg/L (2,300 �g/L). Recent annual average
concentrations ranged from 0.0014 to 0.0016 mg/L (1.4 to
1.6 �g/L). Because of mercury abatement activities, mercury loading
to EFPC from the Y-12 Plant has decreased significantly. Average
daily values were about 60 g/day in the early 1980s, whereas recent
values are nearly 15 g/day, representing a 75% decrease in
mercury releases during the past decade.
All radiological measurements at Station 17 were well below the
DCGs. The summed percentage of DCGs for measured radionuclides at
Station 17 was 2.5%. The largest single contributor to this total
was 238U. The median value for 238U at this
location for 1995 was 6.6 pCi/L, which represents 1.1% of the
DCG. In 1995, the total uranium and associated curies released from the
Y-12 Plant, as measured at Station 17 on
UEFPC, was 143 kg, or
0.069 Ci (2.6 � 109 Bq).
Sampling locations S19 (formerly Outfall 302 at Rogers Quarry) and
304 on BCK 4.55 are considered in-stream sampling points for McCoy
Branch and Bear Creek. In past years, coal bottom ash slurry was
discharged to the McCoy Branch Watershed from the Y-12 Steam Plant.
Bear Creek water quality is affected by area source runoff and
groundwater discharges from waste disposal sites. Of measurements
collected and comparisons made to state water quality criteria for
surface water surveillance, selenium, silver, arsenic, cadmium, and zinc
exceeded the criteria at Rogers Quarry. This was because the
analytical-method detection limits for these parameters exceed the water
quality criterion (0.00015 mg/L). At Outfall 304, silver,
arsenic, cadmium, mercury, selenium, and zinc exceeded water quality
criteria because the analytical method detection limits exceed the water
quality criterion.
Additional surface water sampling is conducted at Outfall 304 by
the Y-12 Plant Groundwater Protection Program
(GWPP) to monitor trends
throughout the Bear Creek Hydrogeologic Regime (see
Sect. 7. ).
In addition to surveillance monitoring via conventional surface water
sampling, the Y-12 Plant has established a series of monitoring
stations on the storm sewer collection system and EFPC. These stations
are officially known as the
SWHISS. The SWHISS network
is designed to monitor and record various surface water parameters to
aid in spill tracking and water quality determination. Ten stations are
currently operational (Fig. 5.14).
Telemetry delivers real-time monitoring data to the Utilities Monitoring
Station 9 and the SWHISS house central computer in Building 9704-1.
Real-time monitoring parameters vary for each site but typically include
pH, temperature, conductivity, dissolved oxygen, and flow. Two locations
on EFPC also measure chlorine.
Analyses were performed to detect radioactivity and conventional,
inorganic, and organic pollutants in the water. Conventional pollutants
are indicated by conductivity, temperature, turbidity, pH, total
dissolved solids, total suspended solids, and oil and grease. Inorganic
parameters are indicated by analyses for metals and anions. The presence
of organic pollutants is indicated by results from total organic carbon
analysis. If the total organic carbon result is greater than
2.5 mg/L, analyses for volatile and semivolatile organic compounds
will be conducted.
There were no high levels of organic compounds detected by the total
organic carbon analysis at either location, as indicated by the maximum
value of 2.1 mg/L at Melton Hill Dam and by the maximum value of
2.2 mg/L at WOC headwaters.
In an effort to provide a basis for evaluation of analytical results and
for assessment of surface water quality, Tennessee General Water Quality
Criteria (TWQC) have been
used as reference values. TWQC for Domestic Water Supply have been used
at Melton Hill Dam; TWQC for Fish and Aquatic Life have been used at WOC
headwaters.
There is reasonably good agreement between parameters measured at WOC
headwaters and those at Melton Hill Dam. The average concentration is
expressed as a percentage of the reference value when the parameter is a
contaminant, the parameter was detected, and a reference value exists.
Three parameters met this criteria; the largest was zinc at WOC
headwaters at 12% of the reference value.
Radiological data are compared with DOE DCGs. The average concentration
for a radionuclide is expressed as a percentage of its DCG when a DCG
exists and when the average concentration is significantly greater than
zero. At the reference locations, only one average for 1995 met the
criteria; the average concentration of 137Cs at WOC
headwaters was less than 1% of its DCG.
Samples are analyzed monthly for radionuclides. Quarterly samples from
the six locations are collected and analyzed for general water quality
parameters, selected metals, and organic compounds. In addition, samples
from K-901-A and K-1007-B are analyzed monthly for
PCBs. Samples from the
remaining locations are analyzed quarterly for PCBs. Radionuclide
results are compared with the DCGs. Nonradiological results are compared
with Tennessee water quality standards for fish and aquatic life, where
such standards are published.
In most instances, results of the analyses for nonradiological
parameters are well below the applicable standards. Lead, nickel, and
mercury were occasionally detected but always in very low
concentrations. For iron and manganese, water quality standards
(WQSs) are sometimes exceeded,
but the WQSs are below the level present in ambient waters. Both
elements are abundant in the soil of East Tennessee, and water samples
collected upstream of K-25 Site operations often show results above
the standards. In addition, natural conditions cause periodic
exceedences of WQSs for dissolved oxygen and pH. During 1995, Aroclor
1254 was detected at K-1007-B and K-1700 on several occasions. However,
in all cases the reported values were below the lowest calibration point
for the analytical method. No other PCBs were detected at these or any
other K-25 surface water monitoring locations.
Dissolved oxygen measurements regularly fall below the minimum water
quality standard during the summer months because of increased
temperature (and therefore lower solubility of the gas) and increased
biological activity. Similarly, increased photosynthesis during the
summer months causes an increase in the pH of area waterways, sometimes
exceeding the maximum water quality standard. Water bodies in the
vicinity of the K-25 Site are regularly inspected for signs of
stress on aquatic organisms during these periods. No evidence that these
conditions have a negative impact on the aquatic communities was
discovered during 1995. For most of the analyses, results are below
detection limits for the instrument and method. Moreover, analytical
results for samples collected upstream of the K-25 Site are
chemically similar in most respects to those collected below the
K-25 Site.
The sum of the fractions of the DCGs for all six sampling locations
remained below the annual limit, as required by DOE Order 5400.5
(Fig. 5.16). The highest sum of the fractions, 2.2% of the allowable sum
of the fractions of the DCGs, was reported for sampling location K-1700.
These results are still well below the conservative limits established
by the order. The 1995 radiological data do not indicate any significant
radiological effects from K-25 Site operations on perimeter surface
waters.
Currently, 3 springs and 16 wells are included in the program.
These locations were selected because of their proximity to the ORR and
because they are located on a representative distribution of sources
from the different geologic formations of the area. They are sampled
semiannually and the results are provided in individual reports to the
owners. Seventeen locations were sampled in February 1995 and again
in August 1995.
Parameters monitored include volatile organics, metals, anions, and the
radioactive parameters: gross alpha activity, gross beta activity, total
radioactive strontium, technetium-99, tritium, and radionuclides
observed in a gamma scan.
In past years, sampling has not indicated any contaminant movement to
these sites, and results from sampling in 1995 continue to support this
finding. The federal DWS for
fluoride and the TWQC for domestic water supplies for lead was
exceeded during both sampling events at one well, and the standard for
nitrate was exceeded at another well during the February event.
At the first well, the fluoride concentration was consistent with the
historical data for the well. The well exceeding fluoride limits is
located deep in the Conasauga formation; the high fluoride concentration
most likely results from natural chemical reactions that can occur in
deep wells that penetrate the Conasauga geologic group. The lead
concentration was higher than previous results.
In the second well, the nitrate concentration was consistent with the
historical data for the well. Nitrate in groundwater is commonly
associated with nearby farming operations and is a likely cause in this
instance.
Federal and state DWSs (40 CFR Parts 141 and 143 and TWQC for
Domestic Water Supply) were used as reference values. If a DWS for a
radionuclide has not been established, then 4% of the DOE DCG for
that radionuclide is used as the reference value. The average
radionuclide concentration is expressed as a percentage of the reference
value when a reference exists and when the average is significantly
greater than zero. In 1995, there were no average radionuclide
concentrations greater than 15% of reference values at the Kingston
Water Treatment Plant and none greater than 16% of reference values
at the Gallaher Water Treatment Plant. The laboratory method used for
total uranium does not permit a test of significance for the maximum and
minimum, but the average concentrations of uranium at both Gallaher and
Kingston were <0.6% of the gross alpha standard
(15 pCi/L). The total uranium measurement is converted to an
activity by assuming natural abundance of uranium isotopes
234U, 235U, and 238U.
Soil is an integrating medium that can contain pollutants originally
released to the air and can thus provide a measure of pollutant
deposition from the atmosphere. Soil sampling and analysis is used to
evaluate long-term accumulation trends.
Soil plots consisting of a known mixture of soil were erected at nine of
the ambient air stations in the fall of 1992 (eight perimeter stations
and the remote station at Norris Dam; see Fig. 5.3). These soil plots eliminate the differences in the mechanics of
transport in the different types of soil found naturally on the
ORR. The soil plot program is
described in detail in the environmental monitoring plan for the ORR.
Vertical composite samples were collected at the nine stations once
during 1995. Samples were analyzed for gross alpha and beta activity,
gamma emitters, total radiological strontium, and uranium. Soil sampling
results are presented in Tables 5.2 and 5.3.
Sediments are effective at concentrating and storing contaminants that
have a high affinity for organic and inorganic surfaces, but they also
contain naturally occurring organic and inorganic chemicals. In
analytical measurements, the naturally occurring chemicals in sediment
lead to higher backgrounds and less sensitivity than those found in
water samples. Sediments are best analyzed for substances that are
concentrated and retained in sediment, resulting in sensitive,
time-integrated measurements of contamination. The program was initiated
in 1993, and the locations are sampled annually. Samples were analyzed
for total metals, chlorinated pesticides,
PCBs, semivolatile organic
compounds, and selected radionuclides.
By examining the 3 years' worth of data available from this program, a
few observations may be made. There is no evidence of PCBs at the Clinch
River locations (CRK 16, 32, 80, and 84), Hinds Creek, the Mitchell
Branch location (MEK 2.1), and Poplar Creek upstream from the
K-25 Site and EFPC
(PCK 22). PCBs, in particular Aroclor-1254 and Aroclor-1260, have
consistently been detected downstream from the Y-12 Plant at
EFK 23.4. Lower levels of PCBs have been detected at EFK 5.4,
and estimated levels have been detected at the remaining sediment
sampling locations.
Metals have been detected at all of the locations. Those that are
especially higher at a particular location are mercury at EFK 23.4
and EFK 5.4, arsenic at MIK 0.1, barium at MEK 2.1, lead
at MIK 0.1 and WCK 6.8, and total uranium at MIK 0.1.
The locations where radionuclides have been detected at consistently
higher concentrations are WCK 1.0 (60Co and
137Cs) and MIK 0.1 (gross alpha and beta,
99Tc, and alpha-emitting isotopes of plutonium, neptunium,
and uranium).
In most cases, these observations reflect the processes occurring nearby
or upstream of the particular sampling location, which is what one would
expect.
Collection and analysis of vegetation samples serves three purposes: to
evaluate potential radiation doses received by people consuming food
crops; to predict possible concentrations in meat, eggs, and milk from
animals consuming grains; and to monitor trends in environmental
contamination and possible long-term accumulation of radionuclides.
The 1995 milk sampling program consisted of monthly grab samples
collected from five locations in the vicinity of the ORR (Fig. 5.20). In 1995, the Solway site was dropped, and a new site was selected in
Karns to ensure sample availability. Milk samples are analyzed at ORNL
for radioactive iodine (131I) by gamma spectrometry and for
total radioactive strontium (89Sr + 90Sr) by
chemical separation and low-background beta counting. Liquid
scintillation is used to analyze for tritium (3H).
The river locations include five sites on the Clinch River and one
location on Poplar Creek (Fig. 5.21):
Sunfish (Lepomis macrochirus
, L. auritus
, and Ambloplites rupestris
) are collected from each of the six river locations, filleted, and
frozen. When enough fish have been collected (typically 150 to 200 per
location), the samples are thawed and fillets from six of the largest
are analyzed for selected metals, pesticides, and
PCBs. The rest (separated into
three composite samples) are ashed and analyzed for 60Co,
137Cs, and total radioactive strontium. To provide data from
a second species, annual catfish sampling was initiated in 1993. Six to
ten catfish are collected at the CRK 16 and CRK 32 locations,
and a composite sample is analyzed for selected metals, pesticides, and
PCBs. A composite sample is also ashed and analyzed for 60Co,
137Cs, and total radioactive strontium.
For PCBs, reported values for sunfish and catfish were below the U.S.
Food and Drug Administration
(FDA) tolerance of 2 ppm;
for mercury, all reported values were below the FDA action level of
1 ppm This has been true for all years of the program. Information
regarding potential health impacts associated with the sunfish and
catfish data is provided in Section 6. . When PCBs have been detected, they have been primarily
Aroclor-1254 and Aroclor-1260, at estimated low levels.
All three hunts this year were gun hunts with two archery-only hunt
areas designated. The two archery-only areas were on the northeast side
of ORNL and in an area next to the Clinch River and Bear Creek. These
areas allowed archery hunting during all three gun-hunt periods. On the
last hunt (December 9-10), hunters were allowed to harvest two deer. The
two-deer limit for a gun hunt was a first for the ORR. The two-deer
limit had been reserved for archery-only hunts.
From the total harvest of 489 animals, 295 (60.3%) were bucks and
194 (39.7%) were does. The heaviest buck had nine antler points and
weighed 176 lb. The greatest number of antler points (13) was found
on a buck weighing 147 lb; however, that deer was confiscated. The
heaviest doe weighed 121 lb.
The sampling areas are selected because of high geese congregation. The
geese are highly mobile animals that range freely to sites on and off
the reservation. For that reason, the results in this report should be
taken as an indication of the possible overall impact that the
reservation has on the geese rather than as an evaluation of the
collection sites.
5.3.1.1 Results
The ORR PAM stations assess the impact to air quality of operations on
the entire reservation. The RAM stations provide information on
reference concentrations of radionuclides and gross parameters for the
region. A comparison of DCG
percentages for the ORR PAM station sampling data with those from the
RAM stations shows that ORR operations do not significantly affect local
air quality (Tables 5.2 and 5.3).
5.3.2 Y-12 Plant Ambient Air Monitoring
In 1994, Y-12 Plant personnel issued Evaluation of the Ambient
Air Monitoring Program at the Oak Ridge Y-12 Plant
(Energy Systems 1994a
) and worked with the DOE and
TDEC in reviewing the ambient
air program for applicability and usefulness of the data. There are no
federal regulations, state regulations, or DOE orders that require this
monitoring. All ambient air monitoring systems at the Y-12 Plant
are operated as a best management practice. With the reduction of plant
operations and improved emission and administrative controls, levels of
measured pollutants have decreased significantly during the past several
years. In addition, processes that result in the emission of enriched
and depleted uranium are equipped with stack samplers that have been
reviewed and approved by the
EPA to meet requirements of
the NESHAP regulations. ORR
air sampling stations, operated by ORNL in accordance with DOE orders,
are located around the reservation. Their locations ensure that areas of
potentially high exposure to the public are monitored continuously for
parameters of concern.5.3.2.1 Uranium
Samples for routine measurement of uranium particulate were collected by
pulling ambient air through a square 14-cm (5.5-in.) filter, which
was analyzed by the Y-12 Plant Analytical Services Organization for
total uranium and for the percentage of 235U. Prior to 1993,
the samples were analyzed for gross alpha and beta and for activity
levels of specific uranium isotopes; however, in 1993, the analysis
program for radionuclides was revised as described in the
Environmental Monitoring Plan for the Oak Ridge Reservation
(EMP) to obtain total uranium
particulate and the percentage of 235U. In this manner,
uranium concentrations in ambient air could be better correlated to
stack emission data, which is also measured as total uranium. For 1995,
the average 7-day concentration of uranium at the 3 monitored
locations ranged from a low of 0.00001 �g/m3 at
Station 8 to a high of 0.00707 �g/m3 at
Station 8 (Table 5.5).
5.3.2.2 Mercury
1995 was the tenth year of an on-site monitoring program established at
the Y-12 Plant to measure mercury vapor concentrations in ambient
air. When originally established, the goals of the program were to
establish a historical database of mercury concentration in ambient air
at the Y-12 Plant, identify spatial and temporal trends in mercury
vapor concentrations at the Y-12 Plant, and demonstrate protection
of the environment and human health from releases of mercury from the
Y-12 Plant to the atmosphere. With the purchase and installation in
late 1995 of near-continuous mercury vapor monitors that provide
readouts at 10-minute intervals, a goal of better understanding the
nature and location of fugitive mercury vapor sources at Y-12 was added.
Outdoor airborne mercury at the Y-12 Plant results primarily from
mercury vaporization from contaminated soils, the burning of coal at the
Y-12 Steam Plant, and fugitive emissions from Building 9201-4, a
former lithium isotope separation facility contaminated with mercury.5.3.3 ORNL Ambient Air Monitoring
The objectives of the ORNL ambient air monitoring program are
(1) to sample at stations that are most likely to show impacts of
airborne emissions from the operation of ORNL and (2) to provide for
emergency response capability. The specific stations associated with
these objectives are 1, 2, 3, and 7 (Fig. 5.6). Sampling is conducted at each ORNL station to quantify levels of
adsorbable gas (e.g., iodine); beryllium; and gross alpha-, beta-, and
gamma-emitting radionuclides (Table 5.7).
5.3.3.1 Results
The ORNL PAM stations are designed to collectively assess the specific
impact of ORNL operations on local air quality. Sampling data from the
ORNL PAM stations (Table 5.7) is compared with air sampling data from the reference stations at
Norris Dam (51) and Fort Loudon (52) (Table 5.2). Comparison of the data in the two tables shows that ORNL has not had
a significant impact on local air quality.5.3.4 K-25 Site Ambient Air Monitoring
The K-25 Site ambient air monitoring program is designed to monitor
selected pollutants for the ongoing monitoring of plant operations
impact on the immediate environment. Specific locations were selected to
determine pollutant concentrations in the prevailing upwind and downwind
directions and radiological measurements in the direction of both the
nearest and most exposed member of the public. The locations of these
monitoring stations are shown in Fig. 5.7. The K-25 Site ambient air monitoring program complies with all
requirements of DOE orders. The
CAA regulations are referenced
by DOE orders as guidance with respect to ambient air
concentrations of certain air contaminants. These regulations specify
24-hour, quarterly, and annual standards for defined pollutants.5.3.4.1 Results
No standards were exceeded and there were no significant elevations of
pollutant concentrations associated with site operations. Sampling
results assessing specific site activities impact on air quality show
that the K-25 Site and the project-specific operations did have a
measurable but not a significant impact on local air quality. These data
also support the state classification of this area, including the
K-25 Site, as in attainment for PM10. Table 5.8 lists selected parameters measured during 1995.5.3.4.2 Criteria Pollutant Levels
Measurements of 24-hour TSP concentrations were performed for all
high-volume samplers. A summary of all TSP measurement results are in
Table 5.9.
For 1995, the 24-hour TSP concentration for all measurement sites
ranged from a low of 6.1 to 99.4 �g/m3. Station K7
demonstrated the highest 24-hour result. Typically, all the sites yield
comparable TSP concentration levels during concurrent monitoring unless
events such as construction or demolition occur, which can produce a
localized impact. TSP is no longer regulated by the state or federal
government. The highest measured value for all stations was
38.2% of the previous 24-hour primary standard and 66.3%of the
secondary standard; both values occurred at Station K7. No
monitoring station measured TSP levels of environmental concern.5.3.4.3 Hazardous Air Pollutant Carcinogen Metal
Levels
Measurements of HAP carcinogen
metals (arsenic, beryllium, cadmium, and chromium) were performed on a
monthly composite of 24-hour samples from each station. The total mass
of each selected metal was determined by ICP-MS analytical technique.
This technique was initiated in 1993, replacing a flame atomic
absorption method. The ICP-MS analytical technique simplified all
chemical analyses to one method. There are no Tennessee or national
ambient air quality standards for HAP carcinogen metals. However,
monthly composite arsenic concentration results for all measurement
sites ranged from less than 0.000001 up to 0.006837 �g/m3.
Monthly composite beryllium concentration results for all measurement
sites was <0.000001 �g/m3. Monthly composite
cadmium concentration results for all measurement sites ranged from
0.000124 up to 0.000601 �g/m3. Composite monthly chromium
concentration results for all measurement sites ranged from less than
0.000001 up to 0.045086 �g/m3. An annual summary of all HAP
carcinogen metals measurement results are in Table 5.12.
5.3.4.4 Radionuclide Levels
Of the radionuclides, only uranium was measured as a monthly composite
of 24-hour samples from each station. The total uranium mass for each
composite sample was determined by ICP-MS analytical technique. The
uranium concentration for all measurement sites ranged from a low of
<0.000001 up to 0.000500 �g/m3 at Station K4
(Table 5.13).
Stations K2 and K4 are in the prevailing downwind direction of
the K-25 Site. The annual average values for all stations were less
than 1% of the annual standard of 0.15 �g/m3 (1.0E-1
pCi/m3) for naturally occurring uranium. Annual results from
Stations K1, K5, K6, and K7 (identified to measure the impact of
demolition activities) did not indicate a measurable uranium
contribution that could be directly attributed to either project. No
uranium concentration levels of environmental concern were measured (see
Fig. 5.11 for 5-year uranium trend).5.3.4.5 Organic Compound Levels
Currently, measurements of organics are performed only during an
operational upset of the TSCA
Incinerator. Five upsets occurred during waste burning operations in
1995 that activated the TSCA ambient air stations and subsequent
measurements of PCBs, furans,
dioxin, and hexachlorobenzene during this reporting period. Sampling and
analytical results showed that there was no off-site impact as a result
of these events beyond that which would result from normal background
levels.5.3.5 Five-Year Trends
Five-year summaries of K-25 Site ambient air monitoring data are
shown in Figs. 5.8, 5.9, 5.10, and 5.11 for TSP, PM10, lead, and uranium only. Other measured pollutant trends
are discussed in this section. Localized operations coinciding with TSP
variations in 1994 and 1995 included logging operations in the areas of
Stations K2, K3, K4, and K7; K-1407 pond closure activities in 1995
in the area of K4; and major demolition activities in 1995 in the areas
of K1, K5, K6, and K7. Variations of PM10 measurements were
insignificant and most likely reflect background concentration
variations of air quality. Lead measurement variations from 1991 through
1993 were primarily due to changes in analytical techniques. From 1993
to the present, lead levels have been declining and most likely reflect
the reduction of lead and lead compounds in motor vehicle fuels. No
variations due to K-25 Site activities could be differentiated from
background levels of this pollutant. Arsenic, beryllium, and cadmium
measurements were initiated in 1993. Arsenic variations in 1995 were
coincidental to demolition activities that affected structural materials
treated with arsenic compounds. No measurements of beryllium have been
above analytical detection limits. Cadmium concentration variations
occurred during 1994 and 1995. This was coincidental to logging and the
pond closure operations. Variations of chromium measurements from 1991
through 1994 show no identifiable K-25 Site contribution. Changes
in analytical techniques were responsible for most of the variations up
to 1994. Chromium variations in 1995 were coincidental to demolition
activities that affected structural materials that had long-term
exposure to chromium compounds. The 5-year trend for uranium indicates
the level of work at the K-25 Site. TSCA Incinerator operations
began during 1991, burning low levels of radiologically contaminated
wastes. The downward trend after 1991 reflects the reduction of
radiological emissions due to K-25 Site and TSCA Incinerator
operations. No monitoring station has measured any pollutant levels of
environmental concern.5.4.1 ORR Surface Water Monitoring
Under the ORR
EMP, samples are collected and
analyzed from 22 locations around the ORR to assess the impact of past
and current DOE operations on
the quality of local surface water. Sample locations are on streams
downstream of ORR waste sources, at reference points on streams and
reservoirs upstream of waste sources, on reference streams off site, and
at public water intakes (Fig. 5.12). Sample locations include the following: 5.4.2 Y-12 Plant Surface Water Monitoring
Routine surface water monitoring that is not required by the NPDES
permit is performed at the
Y-12 Plant site for a
variety of reasons, and various radiological and nonradiological
parameters are monitored. Monitoring results are compared with state
water quality criteria and with DOE order requirements. Data collected
for nonradiological parameters are compared with Tennessee water quality
criteria if a criterion exists for a given parameter. The most
restrictive of either the fresh water fish and aquatic life criterion
maximum concentration (CMC) or
the ``recreation concentration for organisms only'' standard
(10-5 risk factor for carcinogens) was used.5.4.3 ORNL Reference Surface Water Monitoring
The net impact of ORNL activities on surface waters is evaluated by
comparing data from samples collected at reference locations with
information from samples collected downstream of the facility. Monthly
surface water samples are collected at two sampling locations to
determine contamination levels before the influence of WOC, the primary
discharge point into Watts Bar Lake from the ORNL plant site. One
sampling location is Melton Hill Dam above ORNL's main discharge point
into the Clinch River. The other sampling location is WOC headwaters
above any ORNL discharge points to WOC (Fig. 4.14).5.4.4 ORNL Radiological Liquid Effluent Monitoring Program Under the EMP
In 1994 monitoring for gamma activity and tritium was added at the ORNL
NPDES Category I and Category II outfalls. Category I
outfalls are storm drains; Category II outfalls are storage area
drains, once-through cooling water, cooling-tower blowdown, and
condensate drains. With the exception of total radioactive Sr at the
Category II outfalls, radionuclides detected at the remaining outfalls
in 1995 were <1% of the DCG for the respective
radionuclide.5.4.5 K-25 Site Surface Water Monitoring
In addition to the ORR surface water surveillance program, surface water
surveillance is conducted at six locations at the K-25 Site
(Fig. 5.15) as a best management practice. The West Fork Poplar Creek and
K-1710 sampling locations provide information representative of surface
water conditions upstream of the K-25 Site. Station K-716 is
located downstream of most K-25 Site operations and provides
information on the cumulative effects of the operations of the
K-25 Site as well as those upstream. The remaining sampling
locations are at points where drainage in the major surface water basins
converges before discharging to Poplar Creek (K-1007-B and K-1700) or to
the Clinch River (K-901-A).5.4.6 Off-Site Spring and Residential Well Monitoring
In 1989, ORNL implemented a long-term program to monitor off-site
residential drinking water quality. The objective of the program is to
document quantitative measurements of selected pollutants in culinary
water drawn from groundwater surrounding the ORR in order to help assure
residents that their drinking water sources have not been adversely
affected by DOE-ORO plant
operations.5.4.7 Off-Site Treated Water Monitoring
The ORNL program for assessing impacts to the Clinch and Tennessee
rivers uses empirical data from samples taken at the Kingston and
Gallaher potable water treatment plants (Fig. 5.17 ). In 1995, composite samples of treated water samples were collected
monthly and analyzed quarterly for total uranium and specific
radionuclides.5.6.1 ORR Sediment
Stream and lake sediments act as a record of some aspects of water
quality by concentrating and storing certain contaminants. Annually,
under the ORR Environmental
Monitoring Plan
, sediment samples are collected at 16 sites near surface water and
biological monitoring locations in and around the reservation
(Fig. 5.18). The sampling sites are as follows: 5.7.1 Hay
Hay is cut on the ORR and sold
to area farmers for fodder. Six areas from which hay is cut have been
identified as potential depositional areas for airborne materials from
ORR sources (Fig. 5.19). Areas 1, 2, and 3 are within the predicted air plume for an
ORNL source and could also be
affected by the
K-25 Site. Baled hay was
collected from each of these three sites and composited for analysis.
Areas 2, 4, 5, and 6 are within the predicted air plume for the
K-25 Site, an ORNL, and a Y-12 Plant source. Baled hay was
collected from each of these sites and composited for laboratory
analysis. Area 6 best represents the combined plumes from all three
sites; baled hay was collected from this site. Area 7, not shown on
Fig. 5.19, represents a reference site near the Norris Dam ambient air
station.5.7.1.1 Results
Hay samples were collected during June 1995, and samples were analyzed
for gross alpha and beta, gamma emitters, iodine, and fluorides. There
were no statistically significant radiological results in any of the
1995 hay samples.5.7.2 Vegetables
Tomatoes, lettuce, and turnips were grown in nine soil plots established
at the ORR ambient air stations as shown in Fig. 5.3. All crops were harvested except tomatoes at Station 35, where a
crop failure occurred. The failure was attributed to natural causes.5.7.2.1 Results
Samples were analyzed for gross alpha and beta, gamma emitters, and
total uranium. Table 5.2 summarizes the results of the sampling effort. The analytical results
indicate that radionuclide concentrations in tomatoes, lettuce, and
turnips do not vary significantly when comparing samples collected at
reference Station 51 with those obtained from the ORR plots or
purchased from representative gardens near ORR plots.5.7.3 Milk
Ingestion is one of the pathways of exposure to radioactivity for
humans. Radionuclides can be transferred from the environment to people
via food chains such as the grass-cow-milk pathway. Milk is a
potentially significant source to humans of some radionuclides deposited
from airborne emissions because of the relatively large surface area
that a cow can graze daily, the rapid transfer of milk from producer to
consumer, and the importance of milk in the diet.5.7.3.1 Results
Radioactivity measurements are reported as the net activity (the
difference between the gross activity and instrument background). A
95% confidence level is used to determine statistical significance.
Concentrations of total radioactive strontium detected in milk were
consistent with averaged concentrations for the region (Table 5.15).
There were no detected concentrations of 131I or
3H. Average values for radioactive strontium were converted
to EDEs and are presented in
Section 6. of this report. Results are consistent with data from previous
years.5.7.4 Honey
Before 1995, honey from privately owned hives in the vicinity of the ORR
was analyzed for radionuclides to determine whether a potential exposure
pathway existed. In 1995, beehives were established on the reservation
at strategic locations at the Y-12 Plant, ORNL, and the
K-25 Site. Honey samples from the hives were analyzed in 1995. The
results of the radiological analysis of honey collected from sites on
the ORR are summarized in Table 5.16.
5.7.5 Fish
Members of the public potentially could be exposed to contaminants
originating from DOE-ORO
activities through consumption of fish caught in area waters. This
exposure pathway is monitored under the ORR environmental monitoring
plan by collecting fish from 14 locations annually and analyzing
edible fish flesh. Sampling locations are located downstream of
DOE activities, at on-site
creek locations, and at one off-site reference location. Sampling sites
are divided into six larger river locations and eight smaller creek
locations. Because of the limited number and size of fish available for
sampling on the creek locations, different fish-processing and
analytical procedures are used. Only results from sampling at river
locations are presented in this report.5.7.5.1 Results
In 1995, most parameters analyzed for in sunfish and catfish were
undetected.5.7.6 White-Tailed Deer
The eleventh annual deer hunts managed by DOE and the
TWRA were held on the ORR
during the final quarter of 1995. ORNL staff, TWRA , and student
members of the Wildlife Society (University of Tennessee Chapter)
performed most of the necessary operations at the checking station.5.7.6.1 Results
Of the 489 deer harvested, 8 were confiscated because they exceeded
established release limits (5 pCi/g for 137Cs and
20 pCi/g for 90Sr). Concentrations of 90Sr in
bone exceeded the confiscation limit in all eight of the deer
confiscated. Concentrations of 137Cs (based on field data) in
the deer released to the public did not exceed 1.3 pCi/g ( is
similar to 4.8E-02 Bq/g). The deer confiscated during the 1995 hunt
represent 1.6% of the total deer harvested. Since the hunts began
in 1985, 5,885 deer have been harvested; a total of 147 (2.5%) were
retained because of radiological contamination.5.7.7 Resident Canada Geese
One objective of the ORR waterfowl program is to determine
concentrations of gamma-emitting radionuclides accumulated by waterfowl
associated with waste disposal areas. Radioactive elements found in
waste material are the primary types of contaminants associated with the
ORR . The annual roundup of Canada geese took place between
June 28 and 30, 1995. During the roundup, whole-body gamma scans
were conducted on 86 geese: 10 geese from ORNL, 20 from the
K-25 Site, 20 from Melton Hill Dam, 21 from Oak Ridge Marina, and
15 from the Y-12 Plant were analyzed. Three geese from each
location were sacrificed, and samples were analyzed; the remaining geese
were released following the gamma scan.5.7.7.1 Results
Of the 86 geese counted in 1995, 56 had concentrations of
137Cs that were considered to be statistically greater than
zero. Of these, the highest concentration, 0.21 pCi/g
(8.0E-03 Bq/g), was found in a goose collected at the
K-25 Site. The average 137Cs concentration in the
56 geese was estimated to be 0.08 pCi/g ( is similar to
3E-03 Bq/g).5.7.8 Turkey Monitoring
Wild turkeys on the ORR are not presently considered a potential pathway
for radiation exposure to humans because there are no permitted turkey
hunts on the reservation or in the surrounding areas. However, proposals
for hunts on the ORR and in both Knox and Roane counties are under
consideration. During the first quarter of 1995, TWRA trapped 12 wild
turkeys on the reservation for relocation to an off-site
wildlife-management area.5.7.8.1 Results
Prior to release, a whole-body count was performed on the birds to
gather preliminary data. Cesium-137 was detected in only one bird at
0.09 pCi/g.