PUBLIC HEALTH ASSESSMENT
PADUCAH GASEOUS DIFFUSION (USDOE)
PADUCAH, MCCRACKEN COUNTY, KENTUCKY
APPENDIX A:
DEMOGRAPHIC INFORMATION
ATSDR collects and analyzes demographic data as part of the health assessment process. We use this information to characterize the people who live in the communities affected by the site. A review of demographic data provides information about who lives in the community, how long people have lived there, and what the current population trends are. The data are generally obtained from the U.S. Census Bureau, which conducts a nationwide census at the beginning of every decade. Data are available for different geographic units: county, city or town, census tract, and census block group. There are 15 census tracts in McCracken County, Kentucky [1]. The census tract containing PGDP consists of five census block groups. We analyzed the data for these different areas and looked for trends. Demographic information was also gathered during site visits and interviews with community members and local officials. These site visits and interviews were especially useful in that they gave us information on population trends within small geographic areas between Census dates (e.g., 1990 through 1997).
Knowing the number of children and elderly people in a community is particularly important, because these people tend to be more sensitive to environmental exposures than the general population. Similarly, knowing the average length of residence is important, since people who have lived in the area longer may be at greater risk of exposures over longer periods of time. Occupational information lets us know if people spend most of their time working at home. Educational attainment, poverty status, and household income indicate the socioeconomic status of the population. This gives us clues about access to health care, and subsistence fishing, hunting, or farming. Subsistence fishers, hunters, and farmers get the majority of their food supply from these activities and may be at greater risk for exposure to environmental contaminants.
This area of Kentucky is predominantly rural. However, information obtained from the Census Bureau and McCracken County Seat suggests that McCracken County's population is growing. The addition of new housing subdivisions west of Paducah City toward Ballard County characterizes the bulk of the growth. There is also an ongoing initiative to bring new industries into the area. These changes will undoubtedly affect the make-up of the population near the site. The following is a description of demographic trends in the communities closest to PGDP.
County Demographic Data
PGDP is located in northwestern McCracken County, Kentucky, near the border of Ballard County and across the Ohio River from Massac County, Illinois. The census data presented here cover all three counties. The analysis covers the years 1980, 1990, and 1996.
Population Data (Table A-1 [1,2])
McCracken County has the largest population of the three counties, at over 60,000, mostly due to the city of Paducah. McCracken was the only county to gain population from 1980 to 1990. The population estimates for 1996 show a population increase of 3.3% from 1990 [3]. None of the counties are densely populated; Ballard and Massac have well under 100 persons per square mile.
All three counties have populations that are around 90% or more white. There was very little change in the racial or ethnic structure of the area from 1980 to 1990. The percentages of the population under age 10 and age 65 or older are also similar for all three counties. There were more elderly people than children in the three counties, which is unusual (the 1990 national percentages are 14.7% under age 10 and 12.6% age 65 and older [4]) but not necessarily uncommon for a rural area--many younger people leave for larger cities in search of better economic opportunities.
Housing and Socioeconomic Data (Tables A-2 and A-3 [1,2,5,6,7])
In 1990, 20% to 25% of the residents in these three counties had lived in their current housing units for over 20 years. In Ballard County, Kentucky, and Massac County, Illinois, 37.2% of the residents had moved into their current housing units within the past 5 years; in McCracken County, Kentucky, that percentage jumps to 46.7. (See Table A-2.)
As is typical of areas with low percentages of children, there are relatively few persons per household in the three counties. (The national average is 2.63 [4], while the average for each of these counties is under 2.45). The vast majority of households in all three counties are owner-occupied, although there were slight increases in the percentages of renter-occupied households from 1980 to 1990. Again, this trend is typical of rural areas with static or declining populations. (See Table A-3.)
The percentage of the population age 25 and older with at least a high school education increased by 10% to 12% for the three counties from 1980 to 1990. That increase is consistent with a national trend toward higher educational levels as the technical skills needed for most jobs continue to become more complex. Median household income increased only modestly from 1980 to 1990, and 17% to 21% of the population lived below poverty level in 1990. Between roughly half and over seven-tenths of employed persons in the three counties worked in "white-collar" occupations in 1990 (managerial, professional, and administrative positions, as well as positions in the retail and service sectors). (See Table A-3.)
Most housing units in Massac and McCracken received municipal or private water. However, about half of all housing units in Ballard had water from other sources, mostly drilled wells. (See Table A-3.)
City or Town Demographic Data
The following is a description of the three major cities or towns near PGDP. Paducah (east of PGDP) is the largest city in the area. The city of Metropolis and the town of Joppa are across the Ohio River in Illinois.
Population Data (Table A-4 [1,2])
Paducah, Metropolis, and Joppa lost between 6% and 8% of their populations from 1980 to 1990. The vast majority of the residents in these towns are white, although in 1990 Paducah and Joppa had populations that were 20.9% and 14.2% black, respectively. There was little evidence of change in the racial and ethnic structure of these three towns during this 10-year period. In 1990 Paducah and Metropolis had many more persons age 65 and older than persons under age 10. In Joppa the percentages were much closer, but the data suggest that all three towns will continue to "grow older" in the future.
Housing and Socioeconomic Data (Tables A-5 and A-6 [1,2,5,6,7])
In all three towns, between 20% and 30% of householders have lived in their current homes for more than 20 years. Nearly half of Paducah's householders moved into their homes between 1985 and 1990, while less than 40% of the households in Joppa and Metropolis fell into that category. That trend is likely due to a larger percent of renter-occupied households in Paducah (renters tend to move more frequently than do homeowners). (See Table A-5.)
As expected in places with larger elderly populations, there are relatively few persons per household, especially in Metropolis and Paducah. While over 70% of Metropolis households were owner-occupied in 1990, Paducah and Joppa were both under 60%. Joppa declined from 74.5% in 1980 to 59.2% in 1990. (See Table A-6.)
As expected, the percentages of persons with at least a high school education increased substantially from 1980 to 1990. Median household income for Joppa declined in that decade, which dramatically increased the number of persons below poverty level. Poverty also increased somewhat in Paducah and Metropolis. (See Table A-6.)
Nearly all housing units in all three towns are served by public or private-company water sources.
Census Tracts Surrounding Paducah Gaseous Diffusion Plant
The following is a description of the census tracts that surround PGDP, an area of 5 to 10 miles of the site consisting of portions of Ballard, Massac, and McCracken counties.
Population Data (Table A-7 [1,2,8])
The area around the site gained just over 6% in total population between 1980 and 1990. No data are available for 1996 at this level, except for the area in McCracken County. From 1990 to 1996, population increased 3% in the area of McCracken County excluding the city of Paducah. Most of this increase occurred in the area near the Plant [3]. A possible reason for the growth is the movement of people from the city of Paducah to outlying areas that fall within those tracts. There was little change in the racial make-up of the area--95% of the population is white. As with the counties and cities in the area, there were more elderly residents than children under age 10; the gap between the two widened from 1980 to 1990.
Housing and Socioeconomic Data (Tables A-8 and A-9 [1,2,5,6,7])
In 1990, over 15% of the householders in the surrounding tracts had lived in their current housing units for more than 30 years. Just under 40% had lived in their housing units for 5 years or less. Between 1988 and 1990 there was approximately a tenfold increase in the number of electrical permits granted for single and mobile homes in McCracken County (excluding the city of Paducah) [9]. Most of the growth is occurring between Paducah and the Ballard County line; this is consistent with the idea that a number of persons may have moved from Paducah to outlying areas. Therefore, there are substantial numbers of both long-term residents and relative newcomers to the area. (See Table A-8.)
The number of persons per household dropped by over 7% during the 10-year period. Three-quarters of all households were owner-occupied, although there was a slight decline in that percentage from 1980 to 1990. There was a modest increase in the value of owner-occupied housing units during that period. (See Table A-9.)
Socioeconomic data were only available for 1990. In 1990, just over 70% of persons age 25 and older had at least a high school education. About 15% of households were below poverty level. One-third of employed persons were in blue-collar occupations. (See Table A-9.)
About one-quarter of housing units got their water from drilled or dug wells or another source other than from a public source or private company. The Department of Energy has offered to provide municipal water to residents of western McCracken County--in an area described in DOE's Water Policy [10]--who previously used private wells. (See Table A-9.)
Site Area
The following is a description of the immediate area containing the site: census tract 0315, block group 2, in McCracken County west of the city of Paducah.
Population Data (Table A-7 [1,2,8])
The site area experienced very moderate population loss from 1980 to 1990. The block group was over 90% white in both censuses and changed little in racial make-up. There were slightly more elderly persons than children under age 10 in 1990, as the percentage of children declined and the percentage of elderly people increased slightly during that time.
Housing and Socioeconomic Data (Tables A-8 and A-9 [1,2,5,6,7])
In 1990, nearly 19% of householders had lived in their current homes for over 30 years, nearly one-quarter had lived in their current homes for over 20 years, and over one-half had lived in their current homes for 5 years or less. Those numbers, together with the high percentage of owner-occupied housing units, suggests a relatively stable, non-transient population in the area; however, the population is now increasing significantly. (See Table A-8.)
Average persons per household declined substantially from 1980 to 1990, from over 2.8 to under 2.6. Nearly 90% of all households were owner-occupied in both decades, which is typical of many rural areas. Nearly one-quarter of all households were mobile homes in 1990; there was a 5% increase in mobile homes from 1980 to 1990. Median value of owner-occupied homes and median rent were both relatively low for both decades. However, there is evidence that the composition of the area may be rapidly changing. In an article in the Paducah Sun, McCracken County Engineer Van Newberry cites an increase in the development of new subdivisions in the area [11]. According to Mr. Newberry, much of the growth is occurring in western McCracken County from Concord to Kevil. There were 21 new subdivisions being developed in this area, between Cairo Road-Woodville Road and U.S. 62, in 1995. The prices of homes range from $120,000 to $150,000. The values of the residential lots have increased dramatically also. Virtually all of these new homes are being provided with public water. (See Table A-9.)
Socioeconomic data for the site area were only available for 1990. Over 71% of persons age 25 and older had at least a high school education. Under 13% lived below poverty level, which is relatively low for the area. Over three-quarters of housing units in the area had water from a public water source or private company. (See Table A-9.)
 Figure A-1. Demographic Statistics (jpg) |
 Figure A-1. Demographic Statistics (pdf) |
Table A-1. County population data table
| McCracken County, Ky | Ballard County, Ky | Massac County, Il | |||||||
| 1980 | 1990 | Change (%) | 1980 | 1990 | Change (%) | 1980 | 1990 | Change (%) | |
| Total persons
Total area (in square miles) Persons per square mile |
61,310
251.14 244 |
62,879
251.14 250 |
2.6
2.5 |
8,798
251.2 35 |
7,902
251.2 31 |
-11.3
-11.4 |
14,990
239.05 63 |
14,752
239.05 62 |
-1.6
-1.6 |
| % white
% black % other races |
89.5
9.9 0.5 |
89.4
10.1 0.6 |
-0.1
0.2 0.1 |
96.2
3.5 0.3 |
96.7
3.0 0.4 |
0.5
-0.5 0.1 |
93.5
6.1 0.3 |
93.6
5.9 0.6 |
0.1
-0.2 0.3 |
| % under age
10
% age 65 and over |
14.4
14.3 |
13.1
16.2 |
-1.3
1.9 |
14.0
17.3 |
11.7
18.1 |
-2.3
0.8 |
13.9
16.9 |
12.6
19.3 |
-1.3
2.4 |
| Sources: [1,2] | |||||||||
Table A-2. Length of residence in current household,
1990: Ballard, McCracken, and Massac Counties
| Ballard | Massac | McCracken | |
| Total households | |||
| Percent householders moving
into current housing unit by
time period
|
|
|
|
| Source: [5] | |||
Table A-3. County housing and socioeconomic data
| McCracken County, KY | Ballard County, KY | Massac County, IL | ||||
| 1980 | 1990 (% change) |
1980 | 1990 (% change) |
1980 | 1990 (% change) |
|
| Total households*
Persons/household % households owner-occupied |
23,459
2.58 71.1 |
25,625 (9.2)
2.41 (-6.6) 68.2 (-2.9) |
3,267
2.66 85.0 |
3,191 (-2.3)
2.44 (-8.3) 82.3 (-2.7) |
5,731
2.57 79.7 |
5,908 (3.1)
2.44 (-5.1) 77.6 (-2.1) |
| Persons 25 and older
% with at least a high school diploma Median income, $ % below poverty level |
38,187
62.9 15,172 NA |
42,531 (11.4)
73.1 (10.2) 22,606 (49.0) 17.2 |
5,521
53.4 12,492 NA |
5,328 (-3.5)
64.2 (10.8) 19,371 (55.1) 21.0 |
9,449
53.1 13,144 NA |
10,068 (6.6)
65.3 (12.2) 19,632 (49.4) 18.2 |
| Employed persons 16
and older
% in blue-collar jobs % in white-collar jobs |
NA
NA NA |
27,571
29.0 71.0 |
NA
NA NA |
3,222
45.1 54.9 |
NA
NA NA |
5,757
36.0 64.0 |
| Housing units
% with water supplied from a public source or private company % with water supplied from a drilled or dug well or other source |
28,312
89.9 10.1 |
27,581 (-2.6)
91.9 (2.0) 8.1 (-2.0) |
3,528
51.9 48.1 |
3,553 (0.7)
51.1 (-0.8) 48.9 (0.8) |
6,188
80.3 19.7 |
6,446 (4.2)
80.4 (0.1) 19.6 (-1.0) |
| * A household is an occupied housing unit, but the term does not include group quarters such as military barracks, prisons, and college dormitories. | ||||||
| Sources: [1,2,5,6] | ||||||
Table A-4. City or town population data table
| Paducah, KY | Metropolis, IL | Joppa., IL | |||||||
| 1980 | 1990 | Change (%) | 1980 | 1990 | Change (%) | 1980 | 1990 | Change (%) | |
| Total persons
Total area (in square miles) Persons per square mile |
29,315
17.56 1,669 |
27,256
17.56 1,552 |
-7.0
---- -7.0 |
7,171
4.91 1,460 |
6,734
4.91 1,371 |
-6.1
---- -6.1 |
535
0.49 1,092 |
492
0.49 1,007 |
-8.0
---- -7.8 |
| % white
% black % other races |
80.6
18.7 0.6 |
78.4
20.9 0.7 |
-2.2
2.2 0.1 |
92.3
7.3 0.4 |
91.9
7.4 0.7 |
-0.4
0.1 0.3 |
85.0
14.6 0.4 |
85.4
14.2 0.4 |
0.4
-0.4 0.0 |
| % under age 10
% age 65 and over |
13.3
19.4 |
13.0
22.2 |
-0.3
2.8 |
11.6
22.1 |
11.7
25.6 |
0.1
3.5 |
15.7
13.5 |
14.8
16.1 |
-0.9
2.6 |
| Sources: [1,2] | |||||||||
Table A-5. Length of residence in current household,
1990: cities of Paducah, Metropolis, and Joppa
| Paducah, KY | Metropolis, IL | Joppa, IL | |
| Total households | 11,955 | 2,889 | 202 |
| Percent householders moving into
current housing unit by time period
|
28.3 13.1 16.9 10.0 11.1 |
23.5 14.8 19.3 11.1 16.8 |
17.3 11.4 20.8 12.4 16.8 |
| Source: [5] | |||
Table A-6. City or town housing and socioeconomic
data
| Paducah, KY | Metropolis, IL | Joppa, IL | |||||||
| 1980 | 1990 | Change (%) | 1980 | 1990 | Change (%) | 1980 | 1990 | Change (%) | |
| Total households1
Persons/household % owner-occupied |
12,050
2.37 59.2 |
11,955
2.21 54.4 |
-0.8
-6.8 -4.8 |
2,892
2.39 75.9 |
2,889
2.24 71.9 |
-0.1
-6.3 -4.0 |
204
2.62 74.5 |
201
2.45 59.2 |
-1.5
-6.5 -15.3 |
| Persons 25 and older
Median income, $ % below poverty |
19,003
11,848 18.7 |
19,007
17,196 24.4 |
0.0
45.1 5.7 |
4,799
11,753 15.9 |
4,776
16,954 17.4 |
-0.5
44.3 1.5 |
318
11,667 24.1 |
309
10,313 43.5 |
-2.8
-11.6 19.4 |
| Employed persons 16
and older
% blue-collar jobs % white-collar jobs |
NA
NA NA |
10,489
75.2 24.8 |
-----
----- ----- |
NA
NA NA |
2,478
27.2 72.8 |
-----
----- ----- |
NA
NA NA |
129
34.9 65.1 |
-----
----- ----- |
| Housing units
% with water supply % with water from drilled or dug well |
12,749
99.7 0 .3 |
13,150
99.8 0.2 |
3.1
0.1 -0.1 |
3,085
99.6 0 .4 |
3,137
99.8 0.2 |
1.7
0.2 -0.2 |
229
98.7 1.3 |
222
100 0.0 |
-3.1
1.3 -0.3 |
| 1 A household is an occupied housing
unit, but the term does not include group quarters such as military barracks,
prisons, and college dormitories. Source: [1,2,5,6] |
|||||||||
Table A-7. Census tract population data
| Census Tracts Surrounding PGDP1 | McCracken County, Census Tract 315, Block Group 2 | |||||
| 1980 | 1990 | Change (%) | 1980 | 1990 | Change (%) | |
| Total persons
Total area (in square miles) Persons per square mile |
23,733
366.13 65 |
25,177
366.13 69 |
6.1
----- 6.1 |
1,383
30.12 46 |
1,366
30.12 45 |
-1.2
----- -2.2 |
| % white
% black % other races |
94.9
4.7 0.4 |
95.0
4.5 0.5 |
0.1
-0.2 0.1 |
91.4
8.5 0.2 |
92.9
6.9 0.2 |
1.5
-1.6 0.0 |
| % under age 10
% age 65 and older |
14.1
15.8 |
12.5
17.4 |
-1.6
1.6 |
16.1
11.5 |
12.4
13.0 |
-3.7
1.5 |
| 1 Census tracts surrounding PGDP include 9501 in Ballard County; 9701, 9702, and 9704 in Massac County; and 314 and 315 in McCracken County. | ||||||
| Sources: [1,2] | ||||||
Table A-8. Census tracts: length of residence in current
household, 1990
(percent householders moving into current housing unit by time period)
| Census Tracts Surrounding PGDP | McCracken County, Census Tract 315, Block Group 2 | |
| Total households | 11, 619 | 519 |
| Years householder moved
into current housing unit
|
24.9 12.9 22.1 10.4 15.2 |
26.5 15.3 26.1 5.3 18.7 |
| Source: [5] | ||
Table A-9. Census tract housing and socioeconomic
data, 1990
| Census Tracts Surrounding PGDP1 | McCracken County, Census Tract 315, Block Group 2 | |
| Total households2
Persons per household % households owner-occupied |
10,008
2.47 78.7 |
531
2.57 88.5 |
| Persons age 25 and older
% with at least a high school diploma Median income, $ % below poverty level |
17,105
70.1 22,630 15.2 |
927
71.4 27,560 12.7 |
| Employed persons age 16 and older
% in blue collar jobs % in white collar jobs |
10,872
36.7 63.3 |
673
38.6 61.4 |
| Housing units
% with water supplied from a public source or private company % with water supplied from drilled or dug well or other source |
10,840
75.6
|
580
75.7
|
| 1 Census tracts 9501 in Ballard
County; 9701, 9702, and 9704 in Massac County; 314 and 315 in McCracken
County. 2 A household is an occupied housing unit, but the term does not include group quarters such as military barracks, prisons, and college dormitories. |
||
| Source: [5] | ||
References
APPENDIX B:
DESCRIPTION AND TABULATION OF COMMUNITY HEALTH CONCERNS
ATSDR identified community concerns about the PGDP through written correspondence, telephone conversations, informal meetings, and public availability sessions. We divided all these concerns into five general categories, and further into sub-categories. For instance, "Health Concerns" is a general category; one of its sub-categories is non-distinct health outcomes. This sub-category is made up of specific outcomes--for example, headaches, dizziness, and fatigue.
To tabulate the concerns, we counted the number of times each general category was mentioned. We also counted mentions of sub-categories, and of specific components of those sub-categories. Since several people mentioned more than one general, sub-category, and specific component per concern, there may be fewer general concerns than the combined number of specific concerns. For example: non-distinct health outcomes were mentioned eight times, but some people mentioned more than one of the specific outcomes. Of the eight times that non-distinct outcomes were mentioned, headaches were mentioned four times, dizziness once, aches twice, pain three times, nausea three times, sinus problems three times, fatigue twice, and other problems five times.
General Areas of Health Concern
Cancer
Concern over cancer was mentioned the most in our correspondence and conversations with community members. Some of the people were concerned about several particular types of cancer, while others did not identify any specific type. Unspecified cancer was mentioned the most, with breast cancer second. There were nine concerns about death from cancer.
Non-Cancer
Non-cancer concerns were documented several times. As with cancer, some people mentioned more than one type of health outcome in this category. Cardiovascular and respiratory problems were cited the most, followed by unspecified conditions. There were two concerns over death from non-cancer health conditions.
Non-Distinct
Non-distinct health concerns were also mentioned. The most common specific complaint was of headaches, followed by pain, nausea, and sinus problems. Most of the concerns in this category were non-specific, for example, "viral-like problems."
Trauma
There was one reference to trauma, which indicated that the person suffered from "burning and blisters." No more detail was given on the nature or specific cause of the problem.
General Areas of Exposure Concern
Media
The overwhelming majority of concerns involved exposure to contaminated drinking water and breathing contaminated air. Exposure to surface water and soil/sediment was also mentioned. Concern about eating contaminated fish, game, fruits, and vegetables also was listed.
Other Issues
Other categories of concern were hazards from waste materials, waste storage (especially depleted uranium stored on site), transportation of waste, cleanup and treatment of contaminated media, monitoring/sampling off site, and future use of this land.
General Areas of Procedural Concern
Issues
There were concerns about "procedural issues" that may or may not have been directly related to health concerns. The most common complaint was the "lack of trust" of the major players involved at the site (Lockheed-Martin Energy Systems, Inc., and the U.S. Department of Energy). The concerns mentioned an information gap and referred to "politics" as a hindrance to community members. Unreliability of data was mentioned, as well as lack of follow-up regarding a community member's specific concern.
Agency
Several agencies were mentioned under "procedural concerns." Lockheed-Martin was mentioned the most, followed by DOE. ATSDR was also mentioned, as (though less often) was EPA. The local health department was mentioned once. There were no references to the state agencies.
General Areas of Population-Level Concern
Of the people who were concerned about specific neighborhoods, the overwhelming majority mentioned Bradford Road, describing it as an area which has a possible cancer cluster. Other populations mentioned included a household, a region larger than the county, the city of Paducah, another neighborhood, and McCracken and Ballard Counties.
General Areas of Subpopulation-Level Concern
Most people who specified a subpopulation were concerned about children. People were concerned about pregnant/lactating women and women of childbearing age, as well as infants and fetuses. People also expressed concern over pets, farm animals, and wildlife.
Health Concerns
| Cancer | |||
| Death = 9 | Musculoskeletal = 2 | Lymphoreticular = 2 | Unspecified = 39 |
| Respiratory = 1 | Hepatic = 0 | Neurological = 3 | Other cancer = 1 |
| Cardiovascular = 0 | Renal/urinary = 0 | Developmental = 0 | Breast = 4 |
| Gastrointestinal = 1 | Dermal = 0 | Reproductive = 0 | Bladder = 0 |
| Hemopoietic = 0 | Ocular = 0 | Endocrine = 0 | |
| Non-Cancer | ||||
| Death = 2 | Musculoskeletal = 0 | Immunological = 0 | Physical = 0 | Genotoxic = 0 |
| Respiratory = 3 | Hepatic = 0 | Neurological = 1 | Low birth wt. = 0 | Other = 3 |
| Cardiovascular = 4 | Renal/urinary = 0 | Learning = 1 | Reproductive = 0 | Metabol. disorder = 2 |
| Gastrointestinal = 1 | Dermal = 0 | Behavioral = 0 | Miscarriage = 0 | Endocrine = 0 |
| Hemopoietic = 0 | Ocular = 0 | Developmental = 0 | Infertility = 0 | Lymphoreticular = 0 |
| Non-Distinct | |||
| Headaches = 4 | Aches = 2 | Sinus = 3 | Body weight = 0 |
| Dizziness = 1 | Pain = 3 | Eye irritation = 0 | Other = 5 |
| Loss of appetite = 0 | Nausea = 3 | Fatigue = 2 | |
| Trauma | |||
| Laceration = 0 | Concussion = 0 | Chemical burn = 0 | Other = 1 |
| Cut = 0 | Other blunt trauma = 0 | Thermal burn = 0 | |
Exposure Concerns
| Media | ||
| Air = 39 | Surface water = 20 | Biota = 20 |
| Soil/sediment = 17 | Groundwater = 39 | Waste materials= 3 |
| Other Issues | |||
| Unspecified other = 12 | Monitoring/sampling = 5 | Cleanup/treatment = 4 | Future land use = 1 |
| Transp. of wastes = 1 | Waste storage = 4 | Emergency response = 0 | Site access = 0 |
Procedural Concerns
| Issues | |||
| Lack of trust = 18 | Unreliable data = 8 | No response/followup= 6 | Don't know what they are doing = 1 |
| Don't listen = 7 | Information gap = 9 | Politics = 9 | Others = 10 |
| Agency | |||
| DOE = 21 | Contractors = 22 | State health dept. = 0 | Other = 2 |
| ATSDR = 4 | EPA= 3 | Local health dept. = 1 | |
Population-Level Concerns
| County = 1 | Neighborhood = 44 | Household = 8 |
| City = 3 | Block = 2 | Regional/beyond county = 8 |
Subpopulation-Level Concerns
| Men = 1 | Children = 5 | Compromised organ = 0 | Alcohol users = 0 |
| Pets/farm animals = 2 | Women = 4 | Elderly = 0 | Altered metabolism = 0 |
| Workers = 5 | Women of childbearing age = 2 | Cigarette smokers = 0 | Other = 0 |
| Cleanup workers = 0 | Pregnant/lactating women = 2 | Low nutrition = 0 | On medication = 0 |
| Wildlife = 3 |
Samples of Individual Concerns
This compilation represents the range of concerns we received about PGDP. We made a conscious effort to remove any personal identifiers.
Health Concerns
Cancer
There is a possible cancer cluster in a residential community approximately two miles east of the plant (Bradford Road area).
I now have cancer, lymphoma. I would like to know if the cause is from this plant? I'm very concerned about the high rate of cancer in this area (Metropolis Lake Road). My husband died. He worked for Union Carbide for several years. In the past three years three other close neighbors died of cancer also.
Are there other [cancer] hot spots other than the Bradford Road area?
I would like to ask why there is so much cancer in the neighborhood of House Road and Ragland Community?
I have lived on Bradford Road all my life. I have developed a lung problem during the last 24 months that seemingly was caused by what I had breathed. I DON'T SMOKE!!
I am concerned about cancer and other health problems on Bradford Road:
I have lived 43 of my 45 years within five miles of the plant. Also, I have worked at the plant. I would be interested in the results of the possible cancer cluster in the Bradford Road area as my son's dad lived there and died of cancer, and my step-father, who moved there years ago, currently has cancer.
I used to live on Bradford Road, but now live in Florida. Since the plant came to Western Kentucky, we have lost 14 people to cancer. Three, who have cancer of the breast, are still living, and several people have lung problems on Bradford Road. I lost my son and husband.
I am concerned with the amount of cancer in this area. During the eight years we lived [elsewhere], we hardly knew of anyone with cancer. Here, in western Kentucky, every family has been plagued by this disease. I do think more research should be done to see what connection, if any, there is.
Not only has Bradford Road been affected by *many cases of cancer*, you can include Ogden Landing Road, Metropolis Lake Road and Woodville Road which surround the plant.
Last, but not least, I had surgery for cancer. I believe I was directly affected by the waste materials and releases from PGDP and their lack of concern for many years about this problem.
We do have concerns with all the plants in and around Paducah and Calvert City. We have heard that our area has an unusually high cancer rate.
A relative retired from Union Carbide with a disability. He died from cancer and asbestosis. One of his doctors asked him if he had been around uranium. Check to see how many more people died who worked at this plant and lived nearby it.
Several of my relatives died of cancer.
Please check out the cancer rate within a ten mile radius of the plant, especially La Center, Kentucky.
At a certain point within less than a mile, we can taste a chemical, and it does affect the throat. Could this be a respiratory or cancer problem?
In Ballard County, Kentucky, there is a very large number of cancer cases, especially among women--breast cancer, brain tumor, etc. A thorough study should be conducted by a private concern.
His father died of cancer. It is unclear which cancer ended up killing him but he suffered from cancer of the bone, lymph, and prostate. It is unknown as to whether one of these sites had primary cancer which metastasized to other areas or if all these cancers originated in the affected organs.
He knew of breast cancer in this area but also indicated that there are some others. There are also some people with "respiratory problems."
In Princeton, Kentucky, there were three deaths in the same family. The father died of stomach cancer, the grandfather died of bone cancer; and people have thyroid cancer.
There are a couple of people with brain cancer. They all go to Nashville to be treated at Vanderbilt. Two fellows who worked in maintenance for the plant died of cancer in their 40's.
Non-Cancer
I have been a resident of Bradford Road for several years. I'm now blind in my left eye and have seizures and never feel good anymore.
My wife has high blood pressure and has mini strokes since 11/94. I developed a heart problem. Our medical bills have run into the hundreds of thousands of dollars, so you can't tell me I haven't been exposed.
What percentage of birth defects and mental retardation occurring within the region may be considered related to radiation exposure from contaminated air and water supplies?
This person has lived in the city of Paducah for the past 29 years. The person complained of high blood pressure and sinus problems.
This person has lived near the Plant for the past 49 years (except for two years "in the service"). This person knew people with "respiratory problems."
Health Concern: respiratory problems, i.e., bronchitis, allergies, nose and throat burning when exposed to hair spray, cigarette smoke, and raking leaves.
Health Concerns: diabetes and blood pressure problems but doesn't think it's related to the site.
Health Concerns: respiratory problems; the whole time she worked at the plant she smelled chlorine; strong colognes or hair spray causes her nose and throat to "shut down." When she worked at the plant, she could smell the fluoride releases when they happened. She would get a sore throat, her sinuses would swell, she would get headaches and allergies.
Non-Distinct
My neighbor has also been affected. The symptoms he reported to his doctor were non-specific "viral like" problems which included fatigue and headaches.
He also had various non-distinct health problems including a rash which affected other family members.
Workers at the plant are under a lot of stress for the following reasons:
a - they are dismissed more easily for making a honest mistake
b - the training is inadequate
A person complained of high blood pressure and sinus problems. Also, throat burning when exposed to hair spray, cigarette smoke, and raking leaves.
Health Concerns: respiratory problems the whole time she worked at the plant and ever since. Sore throats, sometimes temperatures, and bronchitis. She would get a sore throat, her sinuses would swell, and she would have headaches. (Most of her fellow employees complained of headaches and allergies.)
I have had various non-distinct health problems including a rash which affected other family members.
Trauma
I have been bothered by skin burning and blisters for the past five years.
Exposure Concerns
Air
Possible inhalation exposures due to past air releases of radioactive and non-radioactive contaminants.
With TVA Fly Ash fall out--this will shorten my life by 10 years.
Possible inhalation exposures due to past air releases of radioactive and non-radioactive contaminants due to lack of "heard warnings."
Why so much smoke from plant, especially when there are low clouds over the area?
One of my main concerns is the *present* exposures to air releases of radioactive and non-radioactive contaminants.
The air we breath is absolutely unbelievable. The odors and pollution are really bad.
What do current and past air and water quality monitoring of the region surrounding these sites and the rivers indicate about radiation levels and pollution from other potentially harmful chemicals?
C310 stack vented uranium, and individual is concerned that emissions are not controlled and may be released to the environment.
Soil
They are worried about radionuclides in the soil and water. They eat a lot of food from their garden.
The public needs to know numbers/names of heavy metals, chemicals, radioactive substances, cubic yards of contaminated soil, etc. that are in and around the plants.
Surface Water
Possible exposure to contaminated surface water and sediments in ditches and streams.
We are concerned about toxic waste being dumped in the Little Bayou Creek and being put in the landfill. When we complained about the smell, they said it was chicken manure and in another case they said the smell was caused by bovine manure.
They have a pond around their house that they use and they drink from a private drinking well.
What do current and past air and water quality monitoring of the region surrounding these sites and the rivers indicate about radiation levels and pollution from other potentially harmful chemicals?
Now there are lots of concern with the contamination of the rivers. He is concerned about the feeder plant in Illinois. He wants to know the extent and the type of container breaks.
Groundwater
Past exposure to and health effects from ingestion of contaminated drinking water (Tc-99, TCE) via private wells.
Is there contaminated ground water west of plant?
I am very concerned about the contaminated drinking water. I am of the belief that groundwater has been monitored closely in the past and strongly hope that it will continue to be.
Why is the well water not checked around here [Kevil] for anything that could be dangerous to our health?
We have a private well that we use "daily," and we fear that we could very well be drinking contaminated water.
I wonder how safe our drinking water really is.
We are on well water, which was fine when we had it thoroughly tested thirty years ago by the health department. Since all the problems at the plant, I have had it tested numerous times, and they said it had a high salt content. How did the salt get there after all these years? The only time it happened was after they drilled test wells about one mile east of my house. I am sure they are putting something in those wells that made my water salty, as well as smells.
Everything travels in all directions, not just east (referring to the groundwater plume).
What are the potential health effects from drinking contaminated water or breathing air following radioactive releases from PGDP and documented groundwater contamination?
He and his family were exposed to contaminated drinking water emanating from the site.
They are worried about wells on the other side of Metropolis being contaminated. They want to know if Metropolis wells were monitored.
They are concerned about the size and location of the plume. They want to know if the plume is to the river or on the other side of the river.
What steps have been undertaken to protect existing underground aquifers and ground water from additional contamination; how are current contamination problems being handled? Is this program adequate?
Biota
Adverse health effects from consumption of contaminated fish and game from the West Kentucky Wildlife Management Area.
Adverse health effects from consumption of contaminated deer over past years.
Exposure to contaminated vegetables and fruit.
We have a garden and grow most of our food here next to the plant. I'm concerned what contaminants we may be exposed to from our food.
Subsistence fisherman/hunter, concerned about health effects of eating animals he catches. He catches and eats crappies, bluegill, some largemouth bass (but not from KOW), and buffalo carp. His wife eats raccoon once or twice/year, and rabbit and he eats squirrel once/year. He use to eat soft shell turtles but he can't find them anymore. He eats about 6 to 7 pounds of fish/month. Location of fishing: Barkley Lake, another fish and wildlife area nearby, KOW at this site, and sometimes pond to right of main gate.
They are also concerned about plutonium in the deer.
She had been on the site to fish from time to time. She fished for several different kinds of fish at various places. Made at least one meal a month from the fish she caught. Locations for fishing: the game reserve; the lake north of the game reserve; lakes near Martin Marietta; north in Barkley County; and in Noah Lake, when it is not drained to be cleaned. Also, the West Paducah Coon Hunters Club and near the TVA plant. Types of fish: Crappie, *Bluegills, Bass, Buffalo, Carp (*most common). Also has cooked turtle once. If the fish is too fatty she will not clean or eat it.
She did not hunt but would eat what was given to her which included: rabbits, ground hog, squirrels, possum, raccoon and turtle. Her concerns:
Waste Materials
We are especially concerned about current/future exposure to radioactive and [other] contaminants that could be released from the 100s or 1000s of barrels of waste stored on site. Those barrels cannot last forever. What can safely be done with their contents?
I believe I was directly affected by the waste materials and releases from PGDP and their lack of concern for many years about this problem.
Another thing that bothers me is the transportation of hazardous waste to and from the plant, and what we would be exposed to in case of an accident.
Other Issues
Are there more serious cumulative impacts that should be investigated and documented that result from multiple exposures to radionuclides and other chemicals to residents in the four-state region surrounding PGDP and the industrial plants?
What harm has been caused by recent releases from the PGDP?
The Paducah Gaseous Diffusion Plant has operated here since the 1950's. It and its feeder plant in Southern Illinois have created some pollution.
They are concerned about Dioxin.
He was familiar with the Site Specific Advisory Board (SSAB) and the impact of other industry on the area contributing to environmental problems.
Procedural Concerns (including Agency)
When a release was made, in the past, they used pounds or kilograms. One pound does not sound bad, but when spread in the atmosphere, one pound is a lot. Why not use cubic feet of ____________ released?
My only request would be that if any releases are encountered that would affect the nearby community, immediate notice be given via TV & radio.
I am of the belief that groundwater has been monitored closely in the past and strongly hope that it will continue to be. I believe there is a need for this facility to be monitored closely.
Why is the well water not checked around here [Kevil] for anything that could be dangerous to our health?
We are on a fixed income. The Water District does not need the exorbitant amount proposed by the Commonwealth of Kentucky Public Health Service Commission. Please don't impose unnecessary expense on our water district. After all--you should be working to "protect" us "not punish"!
Now they claim they are making headway in correcting these problems. Do I believe that? NO! Please LISTEN. I speak for this whole community. Talk is cheap and that's about all we've had around here.
I appreciate you concerns, however our complaints have fallen on deaf ears.
I have complained about my well water being ruined, but nothing is being done. They will not hook me on to city water, even though they have others very near me. If you have any power, please use it to help us out. However, I figure I have wasted my time replying to this letter, as it will just be some more government propaganda paperwork, as has been with this environmental group at the plant now. Nothing is ever accomplished.
We are on well water, which was fine when we had it thoroughly tested thirty years ago by the health department. Since all the problems at the plant, I have had it tested numerous times and they said it was a high salt content. How did the salt get there after all these years? The only time it happened was after they drilled test wells about 1 mile east of my house. I am sure they are putting something in those wells that made my water salty, as well as smells.
We are concerned about all of the health concerns affiliated with PGDP. We have eaten game from the WKWMA for the past 20 years, and we feel we should be kept informed of all exposures to waste material and any and all releases from the PGDP.
Concern: Lack of trust in reports from PGDP.
On cleaning the groundwater, this is one of the biggest rip-offs I've ever seen. Take water, clean it, and put it back in a dirty container? How stupid can people be? The company doing this is just getting rich at the taxpayer's expense.
We were told our water would be checked in a 6 mile radius 3 to 4 years ago, and we are still waiting.
We have no say in what is buried in the landfill they are building--this is not right.
How can citizens gain better access to data on recent releases from the PGDP and more importantly, to appropriate interpretations of these data in terms of both possible short and long-term effects?
To what extent are local health departments participating in the monitoring of air and water quality for the region surrounding these sites and the rivers? If they are not, how can citizens pressure them to become more involved with this issue?
He believes that the DOE is insensitive to the concerns of citizens affected by the site, specifically people exposed to contaminated water and workers exposed on site. He also believes that their environmental data is unreliable, especially concerning past releases into the atmosphere.
He thinks the DOE and Lockheed Martin are insensitive to the concerns of citizens who are affected by the contamination. He also thinks that DOE is covering up other environmental problems that may be ongoing.
Some complaints about Lockheed-Martin Energy Systems:
They were concerned about the plant increasing capacity since it was privatizing and were worried about how the new owners would be regulated.
He is concerned with the change in ownership (of the plant).
Noticed that there is more train traffic in/out of Plant recently. Sirens are not loud enough for when inside house with TV playing.
Wants owner of plant to be responsive to citizens, get large volumes of a report to citizens when it is available in the library. Make reports available on computer diskettes for citizens, libraries, and schools that have PC computers.
There is confusion among citizens on the relationships between DOE, Lockheed-Martin Energy Systems, NRC, KY Federal Facilities Oversight Unit, KY Department of Health Services, ATSDR, USEPA, etc.
With the Avlis technology imminent, the present level of each contaminant needs to be known. Then a plan needs to be formulated as to how these pollutants can be cleaned up and who will clean them up.
The public needs to know numbers/names of heavy metals, chemicals, radioactive substances, cubic yards of contaminated soil, etc. that are in and around the plants. Murray State University and/or Southern Illinois University could assist in the testing. Until it is known just exactly what we are dealing with and who created the problems, we are just jousting with windmills.
Numbers and cleanup plans are needed. Will all the pollution problems be left to our local economy? Or will the governing agency who created the problems be held responsible for their waste management?
They were familiar with the Calvert City study and thought the results were swept under the rug about the elevated levels of acetone. They would like to see more cooperation with the Illinois side of the community.
Need to build trust with the community--vision of non-trusted government agency. No longer subject to FOIA, ending comment period of NEPA regulations which exclude small waste sites and transportation.
For years there was no enforcement of workers regarding wearing personal protective equipment (PPE). Since 1991, PPE has been required for the same job. The following concerns fall out of this:
How much waste is stored; what happens if a container breaks?
Population-Level Concerns
Possible cancer cluster in residential community ~ 2 miles east of plant (Bradford Road area).
I'm very concerned about the high rate of cancer in this area (Metropolis Lake Road).
The cancer cluster on Bradford Road is of concern to us as well.
Possible problems of residents nearer the plant.
I would like to ask why there is so much cancer in the neighborhood of House Road and Ragland Community?
Why is the well water not checked around here [Kevil] for anything that could be dangerous to our health?
I and my immediate household, probably have less concern for potential health problems than others. Nevertheless, I would be interested in the results of the possible cancer cluster on Bradford Road.
Not only has Bradford Road been affected by *many cases of cancer*, you can include Ogden Landing Road, Metropolis Lake Road and Woodville Road which surround the plant.
We do have concerns with all the plants in and around Paducah and Calvert City. We have heard that our area has an unusually high cancer rate.
Several other neighbors and relatives, young and old . . . someone nearly every week (gets cancer).
Please check out cancer rate within a ten mile radius of the plant, especially La Center, KY.
In Ballard County, KY there is a very large number of cancer cases, especially among women--breast, brain tumor, etc.
How were residents downstream of PGDP affected?
How were the residents downstream from Calvert City been affected?
Other people in his neighborhood have also been affected.
Subpopulation-Level Concerns
Children
I am very concerned about past, present, and future exposures and health outcomes (cancer and non-cancer) for my neighbors, children, and grandchildren.
What are the potential health effects on children whose parents have worked at PGDP or who have been exposed to contaminated air and water supplies?
What percentage of birth defects and mental retardation occurring within the region may be considered related to radiation exposure from contaminated air and water supplies?
Workers
What health impacts may have been initiated by PGDP operations during the period 1944 to the present? How were workers affected? How were workers' families affected?
Is the drinking water used in the plant treated for chemical contaminants (since it comes from the Ohio River)? Why do management people use bottled water? Can ATSDR have someone check water used for drinking on-site?
Workers are under a lot of stress for the following reasons:
Wildlife
I am concerned about the wildlife (especially in the game reserve). I think you should keep a closer watch on that aspect--concern about wildlife.
To what extent are animals (including fish, game, and cattle) affected by radionuclide levels in the water and in regional plants?
Why was deer found with plutonium in the muscle?
He noticed that there are no grasshoppers, frogs, or snakes on the farm. Also, there are few birds and other insects. The reduction in these animal and insect populations happened about 3 or 4 years ago.
He never observes live or dead fish in the creek. In 1993 or 1994, over 20 deer were found dead near Spring Bayou Church. The plant was told of the dead deer and did investigate.
Pets/Farm Animals
Cattle look older than they should. In 1994, a calf was born dead with a deformed jaw. Coffee Animal Clinic in LaCenter, Kentucky examined the calf; then the Plant took the calf. Presently has 40 head of cattle including calves. In 60 years, there was only the one deformity.
APPENDIX C:
HEALTH GUIDELINES, COMPARISON VALUES, AND EXPOSURE FACTORS
When a hazardous substance is released to the environment, people are not always exposed to it. Exposure happens when people breathe, eat, drink, or make skin contact with a contaminant. People can also be exposed to radioactive contaminants by irradiation--if they get close to the radioactive material and if the contaminants are present at high concentrations.
Several factors determine the type and severity of health effects associated with exposure to contaminants. Such factors include exposure concentration, frequency and duration of exposure, route of exposure, and multiplicity of exposure (i.e., the combination of contaminants and routes). Once exposure takes place, individual characteristics--such as age, sex, nutritional status, genetics, lifestyle, and health status--influence how that person absorbs, distributes, metabolizes, and excretes the contaminant. These characteristics, together with the exposure factors discussed above and the specific toxicological effects of the substance, determine the health effects that may result.
ATSDR considers these physical and biological characteristics when developing health guidelines. Health guidelines provide a basis for evaluating exposures estimated from concentrations of contaminants in different environmental media (soil, air, water, and food) depending on the characteristics of the people who may be exposed and the length of exposure.
ATSDR reviews health and chemical information in documents called toxicological profiles. Each toxicological profile covers a particular substance; it summarizes toxicological and adverse health effects information about that substance and includes health guidelines such as ATSDR's minimal risk level (MRL), EPA's reference dose (RfD) and reference concentration (RfC), and EPA's cancer slope factor (CSF). ATSDR public health professionals use these guidelines to determine a person's potential for developing adverse non-cancer health effects and/or cancer from exposure to a hazardous substance. ATSDR does not have guidelines for exposure to radioactive materials. Instead, the agency uses existing regulatory values and national or international recommendations.
An MRL is an estimate of daily human exposure to a contaminant that is likely to be without an appreciable risk of adverse non-cancer health effects over a specified duration of exposure (acute, less than 15 days; intermediate, 15 to 364 days; chronic, 365 days or more). Oral MRLs are expressed in units of milligrams per kilogram per day (mg/kg/day); inhalation MRLs are expressed in micrograms per cubic meter (µg/m3). MRLs are not derived for dermal exposure.
RfDs and RfCs are estimates of daily human exposure, including exposure to sensitive subpopulations, that are likely to be without appreciable risk of adverse non-cancer health effects during a lifetime (70 years). These guidelines are derived from experimental data and lowest-observed-adverse-effect levels (or no-observed-adverse-effect levels), adjusted downward using uncertainty factors. The uncertainty factors are used to make the guidelines adequately protective of public health. RfDs and RfCs should not be viewed as strict scientific boundaries between what is toxic and what is nontoxic.
For cancer-causing substances, EPA established the CSF as a health guidance. A CSF is used to determine the number of excess cancers expected from maximal exposure for a lifetime.
Comparison values are estimated contaminant concentrations that are unlikely to cause detectable adverse health outcomes when these concentrations occur in specific media. Comparison values are used to select site contaminants for further evaluation. They are based on health guidelines. Comparison values are calculated using conservative assumptions about daily intake rates by an individual of standard body weight. Because of the conservatism of the assumptions and safety factors, contaminant concentrations that exceed comparison values for an environmental medium do not necessarily indicate a health hazard.
For nonradioactive chemicals, ATSDR uses comparison values like environmental media evaluation guides (EMEGs), cancer risk evaluation guides (CREGs), reference dose (or concentration) media evaluation guides (RMEGs), and others. EMEGs, since they are derived from MRLs, apply only to specific durations of exposure. Also, they depend on the amount of a contaminant ingested or inhaled. Thus, EMEGs are determined separately for children and adults, and also separately for various durations of exposure. A CREG is an estimated concentration of a contaminant that would likely cause, at most, one excess cancer in a million people exposed over a lifetime. CREGs are calculated from CSFs. Reference dose (or concentration) media evaluation guides (RMEGs) are media guides based on EPA's RfDs and RfCs.
EPA's maximum contaminant levels (MCLs) are the maximum contaminant concentration of a chemical that is allowed in public drinking water systems. MCLs are regulatory standards set as close to health goals as is feasible and are based on treatment technologies, costs, and other factors.
For radiological contaminants, ATSDR uses information on radiation exposure and its effects related to environmental levels prepared by federal agencies, including EPA, DOE, and the US Nuclear Regulatory Commission. The agency also uses other publicly available data sources and recommendations on radiation dose limits. The National Council on Radiation Protection and Measurements (NCRP), the International Commission on Radiological Protection (ICRP), and the United Nations Scientific Committee on the Effects of Atomic Radiation are a few of the sources.
ATSDR uses standard or site specific intake rates for inhalation of air and ingestion of water, soil, and biota. Table C-1 presents the intake rates for groundwater, surface water, soil, and sediment that we used in estimating doses for PGDP. (The dose calculation equations, and our assumptions about exposure factors, are derived from the ATSDR Public Health Assessment Guidance Manual [1].) For screening purposes, ATSDR often uses the maximum contaminant concentration detected in a specific medium at a site to identify contaminants requiring specific exposure evaluations; using the maximum concentration results in a more protective evaluation. When unknown, the biological absorption of a substance within the human body is assumed to be 100%.
After estimating the potential exposure at a site, ATSDR identifies the site's "contaminants of concern" by comparing the exposures of interest with health guidelines, or contaminant concentrations with comparison values. As a general rule, if the guideline or value is exceeded, ATSDR evaluates exposure to determine whether it is of potential health concern. Sometimes additional medical and toxicological information may indicate that these exposures are not of health concern. In other instances, exposures below the guidelines or values could be of health concern because of interactive effects with other chemicals or because of the increased sensitivity of certain individuals. Thus additional analysis is necessary to determine whether health effects are likely to occur.
Exposure doses via ingestion are calculated on the basis of the following equation:
Dose (Ingestion) = (Chemical Conc. x IR x EF x ED) / (BW x AT)
where:
Chemical Conc. = concentration of each contaminant IR = ingestion rate EF = exposure frequency in days per year ED = exposure duration in years BW = body weight in kilograms AT = averaging time in days
For soil and sediment doses, we take an additional step to determine exposure via dermal absorption, with the total dose being the sum of the ingestion dose and the dermal dose.
Dose (Dermal) = (Chemical Conc. x ABS x TSA x EF x ED) / (BW x AT)
where all factors are as above except:
ABS = a chemical-specific absorption or bioavailability factor (unitless) TSA = total soil adhered in milligrams (skin surface area x soil adherence value)
Once we have calculated the dose (in mg/kg/day) for a contaminant, we evaluate that contaminant's non-cancer and cancer health effects. For the former, we compare the dose with studies that have investigated the health effects of exposure to the contaminant. For the latter, we multiply the dose by the pathway-specific CSFs which are expressed in units of inverse dose--that is, (mg/kg/day)-1.
Excess Cancer Risk = Dose (mg/kg/day) x Cancer Slope Factor (mg/kg/day)-1
The excess cancer risk is the expected increase in cancer risk due to contaminant exposure. All of the uncertainties and health-protective exposure assumptions associated with the dose calcuations are included in the risk estimation, as well as the uncertainty in deriving the CSF. Excess cancer risks are described by the following categories [2]:
No increased risk less than 1 per 100,000 < 0.00001 No apparent increased risk 1 per 100,000 0.00001 Low increased risk 1 per 10,000 0.0001 Moderate increased risk 1 per 1,000 0.001 High increased risk 1 per 100 0.01 Very high increased risk more than 1 per 100 > 0.01
None of the excess cancer risk estimates necessarily indicate that exposure to carcinogenic contaminants will result in cancer in the exposed population.
References
Table C-1. Dose equations and factors used in calculating
exposure doses at PGDP
| Dose Parameters | Groundwater | Surface Water | Soil | Sediment |
| Ingestion rate WKWMA workers Adults Children Pica children |
2 liters/day 2 liters/day 1 liter/day 1 liter/day |
0.5 liters/day 0.5 liters/day 0.5 liters/day None |
200 mg/day 50 mg/day 200 mg/day 2,000 mg/day |
100 mg/day None 100 mg/day None |
| Total soil adhered (for dermal contact) WKWMA workers Adults Children Pica children |
NA NA NA NA |
NA NA NA NA |
37,600 mg 9,400 mg 5,250 mg 3,000 mg |
9,400 mg 5,250 mg 3,000 mg |
| Exposure frequency WKWMA workers Residents (adults and children) |
All groundwater exposures based on residential scenario |
12 days/year 12 days/year |
1.5 days/week 5.6 days/week |
0.75 days/week 12 days/year |
| Exposure area (location of stations used to determine 67th percentile concentration) |
All groundwater exposures based on specific well data | All surface-water stations outside of security fence | WKWMA workers:
buffer zone stations
Residents: stations outside buffer zone |
All sediment stations outside security fence |
| Exposure duration | ~14 years (1974-1988) |
30 years (adult) 6 years (child) |
30 years (adult) 6 years (child) 3 years (pica child) |
30 years (adult) 6 years (child) |
| Body weight Adults Children Pica children |
70 kg 13 kg 10 kg |
|||
| Averaging time Non-cancer (exposure duration x 365 days)
|
Adult: 30 years x 365 days/year Child: 6 years x 365 days/year Pica child: 3 years x 365 days/year 70 years x 365 days/year | |||
| This table does not include information for the food and biota pathway; see the food and biota section of the public health assessment. | ||||
| Key: kg = kilograms; mg = milligrams; mg/day = milligrams per day; WKWMA = Western Kentucky Wildlife Management Area | ||||
APPENDIX D:
ESTIMATION OF EXPOSURE DURATION FOR GROUNDWATER PATHWAY
Four residences near the northwest boundary of PGDP were exposed to trichloroethylene (TCE) and technetium 99, and possibly to lead, pentachlorophenol, and vinyl chloride via contaminated groundwater. The exposure occurred via ingestion of and dermal contact with groundwater, and inhalation of vapors from contaminated groundwater. Residents were provided with an alternate water source upon discovery of the contaminants in August 1988.
Very little groundwater monitoring took place before 1988, so monitoring data cannot be used to determine the duration of contaminant exposure. The rate of contaminant transport after 1988 has been used to estimate the annual rate of contaminant migration. The locations of the 100-microgram-per-liter TCE isocontours were qualitatively interpreted from monitoring data for 1988, 1991, and 1995. (This concentration was chosen not for health reasons but for better reliability in the data.) These contours were interpolated using maximum annual concentrations from residential and monitoring wells. The contouring procedure locates the line of equal concentration (100 µg/L) based on point values and the distances between adjacent values.
Figure D-1 shows isocontours for 1991 and 1995, which were drawn using ArcView overlaid on a site map. ArcView's map measurement tool was used to measure the plume progressions from 1988 to 1991 and from 1991 to 1995. These distance measurements divided by the number of years of plume progression (3 years and 4 years, respectively) yield a plume progression rate between 125 and 330 meters per year, depending on the time interval (1988-1991, 330 meters per year; 1988-1995, 207 meters per year; 1991-1995, 125 meters per year); see Table D-1.
Table D-1. Estimated plume migration rates based on
plume locations for different time periods
| Time Period | Plume Progression | Annual Migration Rate |
| 1988-1991 (3 years) | 960 meters | 330 meters/year |
| 1988-1995 (7 years) | 1,450 meters | 207 meters/year |
| 1991-1995 (4 years) | 500 meters | 125 meters/year |
The largest uncertainty associated with estimating the exposure duration is in interpreting the TCE isocontours. The 1988 contour is based on 21 annual data points (maximum values at each well), which are irregularly distributed. Because the data set is limited, the resulting isocontour represents a conservative estimate. The 1988 isocontour is approximately 1,200 meters (0.75 miles) downgradient of the residential well closest to the site boundary. The small number of data points used to interpret the location of the 1988 plume suggests that the 1988 plume had progressed at least that far but probably had progressed further. Also, the time between measured TCE concentrations was rounded to annual values. The data values used to generate the contours are annual maximums, which occurred at approximately the same time each year.
Site personnel estimate plume migration at about 1 foot (30 centimeters) per day, which adds up to 110 meters per year. (This information came from a January 22, 1998, communication with Brad Montgomery of Bechtel Jacobs Company and a February 2, 1998, communication with Ross Miller of Geo Consultants, LLC.) This estimate is based on extensive flow modeling and the measured migration rate of tracers injected into the Regional Gravel Aquifer (RGA). Given the abovementioned uncertainty about the 1988 isocontour's location, we used a contaminant migration rate of 110 to 125 meters per year to evaluate the duration of contaminant exposure.
Table D-2 indicates the distance that the contaminant plumes have migrated beyond the affected residential wells. The 1991 and 1995 isocontours show that the plume has moved 2,200 meters (as of 1991) and 2,640 meters (as of 1995) downgradient of the wells. Dividing these distances by the annual migration rate of 125 meters per year provides an estimate of the total duration of plume migration. Subtracting the years of post-1988 migration from this total provides an estimate of the pre-1988 exposure duration. Using the 1991 and 1995 plume locations, the estimated pre-1988 exposure durations are 14.6 and 14.1 years (Table D-2). This estimate is for those wells closest to the site boundary (RW-002 and RW-113). Exposures for wells further downgradient would be of shorter duration. Also, this exposure duration is for TCE concentrations greater than 100 µg/L. Exposures at lower concentrations probably had a longer duration.
Table D-2. Estimated exposure durations, based on
125 meters per year migration rate and distance of plume migration downgradient
of residential wells
| Plume Distance Beyond Residential Wells | Years Migration Past 1988 Exposure | Estimated Duration of Exposure (using 125 meters/year migration rate) |
| 1988: 1,200 meters | 0 years | 9.6 years |
| 1991: 2,200 meters | 3 years | 17.6 years - 3 years = 14.6 years |
| 1995: 2,640 meters | 7 years | 21.1 years - 7 years = 14.1 years |
TCE concentrations in the affected wells probably varied considerably over the exposure period. While there are no data for this period, well concentrations in the years after 1988 indicate significant variation in concentrations. (See Figure 5 in the main body of this report.) These variations are probably due to the changes of seasonal water levels in the Ohio River (i.e., river stages). Changes in the river stage directly affect both flow rate and direction in the RGA. In the case of well RW-017, high TCE concentrations correspond with times of lower river stages. Although we used maximum annual concentrations to calculate exposure doses (Table 5 in the main body of this report), ingested concentrations probably varied by a factor of two.
 Figure D-1. TCE Isocontours (1991-95) and Contaminated Off-Site Well Locations (jpg) |
Figure D-1. TCE Isocontours (1991-95) and Contaminated Off-Site Well Locations (pdf) |
APPENDIX E:
EXPOSURE TO AIRBORNE RADIONUCLIDES
Exposure doses to airborne radionuclides were estimated using the Clean Air Act Assessment Package--1988 (CAP88), a system developed by EPA [1,2]. CAP88 uses a modified Gaussian plume equation to estimate the average dispersion of radionuclides released from up to six sources. The sources can be either elevated stacks, such as a smokestack, or uniform area sources, such as a pile of uranium mill tailings. Plume rise can be calculated assuming either a momentum or buoyancy-driven plume. Assessments are done for a circular grid of distances and directions with a radius of 80 kilometers (50 miles) around the facility.
The program computes radionuclide concentrations in air, rates of deposition on ground surfaces, concentrations in food and intake rates to people from ingestion of food produced in the assessment area. Estimates of the radionuclide concentrations in produce, leafy vegetables, milk, and meat consumed by humans are made by coupling the output of the atmospheric transport models with the U.S. Nuclear Regulatory Commission Regulatory Guide 1.109 terrestrial food chain models.
Dose and risk estimates from CAP88 are applicable only to low-level chronic exposures, since the health effects and dosimetric data are based on low-level radionuclide intakes. The population estimates used in this evaluation are the 1980 Census data provided with the CAP88 model. In addition to population estimates, the model requires information on radionuclide emission rates, meteorological data, and agricultural data on consumption of locally grown food and dairy products. Radionuclide emission data were obtained from the annual site environmental monitoring reports.
The two meteorological data sets that were used in the evaluations are provided with the CAPP88 model. The 1950s emission years used 1960-1964 meteorological data; the 1996 emission year evaluation used 1989-1993 meteorological data. Agricultural input data, stack parameters, and source partitioning were based on information provided in the 1996 National Emission Standards for Hazardous Air Pollutants (NESHAP) report [3]. Four sources account for most PGDP radionuclide emissions: the C-310 stack, C-400 combined sources, the seal and wet air exhausts, and the C-710 laboratory. CAP88 places all sources at the center of the facility with respect to the surrounding population and varies only the height of the release. This evaluation used a zero plume rise factor based on emission temperature and velocity information in the NESHAP report.
The radionuclides evaluated include technetium 99, uranium 234, uranium 235, and uranium 238. The results reported in Table E-1 are for 1956 through 1959 (the years with the largest releases) and for 1996 (a recent year for which there is complete information). The uranium isotope releases were partitioned between the sources in the following proportions for all years:
Although these proportions may have changed with process and control operations, any variations in the sources had minimal effect on the estimated dispersion concentrations, because CAP88 locates all emissions at the same geographic point and because a zero plume rise was used.
Table E-1. Annual radionuclide emissions for selected
isotopes and years [4,5,6,7]
| Year | Technetium 99 in curies (gigabecquerels) | Uranium 234 in curies (gigabecquerels) |
Uranium 235 in curies (gigabecquerels) |
Uranium 238 in curies (gigabecquerels) |
| 1956 | 2.6 (96.2) | 1.62 (59.94) | 0.08 (2.96) | 3.50 (129.5) |
| 1957 | 4.8 (177.6) | 1.10 (40.7) | 0.05 (1.85) | 1.20 (44.4) |
| 1958 | 6.3 (233.1) | 1.09 (40.33) | 0.05 (1.85) | 1.16 (42.92) |
| 1959 | 5.1 (188.7) | 0.93 (34.41) | 0.04 (1.48) | 1.10 (40.7) |
| 1996 | 0.04 (1.48) | 0.003 (0.111) | 0.0001 (0.004) | 0.001 (0.037 |
In addition to the chronic or long-term process releases, accidental releases of UF6 have occurred throughout the operating history of the PGDP facility [8,9]. The largest reported accidental release occurred in 1960, when a cylinder ruptured releasing about 11,000 pounds (approximately 5,000 kilograms) of UF6 . This accident occurred in Building C-333 on November 17, 1960, at about 4:00 a.m. Another accidental release occurred during a fire at Building C-337 in December 1962. About 5,062 pounds (2,278 kilograms) of UF6 were released during the fire.
Acute airborne uranium hexafluoride (UF6) concentrations near PGDP from the 1960 and 1962 accidents were estimated using the RASCAL 3.0 air dispersion and dose model [10] and weather observations from the Paducah/Barkley Airport [11]. The RASCAL model (beta test version) provides a general assessment of potential uranium air concentrations following accidental releases. Due to the confluence of the water vapor from PGDP cooling towers with any airborne releases, atmospheric humidity is assumed to be similar to conditions of light precipitation.
Our data on weather conditions at the time of the 1960 release indicate a stable to very stable atmosphere (stability class F), very low wind speed from the northwest, and a temperature of 39oF (dry bulb) [11]. Under these release conditions and according to our modeling of this accident, an estimated uranium inhaled radiation dose of 1.5 rem (0.015 sieverts) and an estimated uranium inhaled chemical dose of 20 milligrams (mg) could have been received by the maximally exposed resident southeast of the site. The U.S. Nuclear Regulatory Commission's action level for intake of soluble uranium is 10 mg. (At this action level, residents may be instructed to evacuate or to stay indoors with windows closed.) A report assessing PGDP accidents [10] indicates that a 5-mg uranium dose can produce detectable, non-permanent kidney damage. The 1960 cylinder rupture could have resulted in inhaled exposure doses of 5 mg to 20 mg to people who lived approximately 2.5 miles (4 kilometers) from the release site. That includes off-site areas to the southeast of the site.
According to accident records, this release occurred on November 17, 1960, at approximately 4:00 a.m. At that time of day and year, it is unlikely that nearby residents would be outside, where exposure to the maximum concentrations would occur. Air temperatures were in the 30s, so windows and doors would have been shut--very little exposure to residents inside their houses probably occurred. Additionally, this exposure scenario assumes that 62% of the UF6 cylinder content was vented from the building over a 1-hour period and became airborne. Notes from accident summaries suggest that a considerable portion of the UF6 remained in the liquid phase and was recovered [9].
Estimated uranium air concentrations and doses from the 1962 fire are much lower than from the 1960 cylinder accident. The explosion and fire that caused this release resulted in much greater atmospheric dispersion and much lower air concentrations and doses. Off-site uranium air concentrations from this accident probably did not present a health hazard to the surrounding community.
In addition to the documented 1960 and 1962 accidents, there were community concerns about two other potential incidents: a 3-day UF6 release on March 15 through 17, 1970; and a large accidental release sometime in 1969 or 1970. A Union Carbide memorandum contained reference to a 3-day UF6 (March 15-17, 1970) that was detected via on-site air monitoring inside the building [8]. This memorandum also indicated that the average gross alpha air monitoring results for the perimeter east location for the period from October 1969 to May of 1970 were higher than normal. However, the individual weekly air monitoring results indicated that this average was elevated for a different time period than March 15-17, 1970 [12]. Also, the plant's original report for this incident indicated that a total of 15 grams of uranium was released inside the building and eventually released through the building ventilation system. This amount of uranium would not have an adverse impact off site. For the second concern (an accident that occurred in 1969 or 1970 when houses to the southeast turned black and trees died), the site accident records for the 1969/70 time frame do not report any events capable of producing significant off-site uranium or hydrogen fluoride concentrations.
However, an extensive review of the weekly air monitoring data indicate that there were several periods of elevated gross alpha and gross beta (presumably, uranium and technetium 99) concentrations at perimeter air monitors during the 1969 and 1970 timeframe [12]. There is some indication that the site investigated elevated gross beta levels to the north of the plant during this time, but there was no explanation of the cause. Due to the limited information available on these specific events, ATSDR cannot evaluate potential exposure doses off site. However, monitoring data do indicate that some type of release event(s) occurred that are not reflected in the accident reports reviewed.
At this time, it is not possible to determine if nearby residents were actually exposed to hazardous concentrations of uranium from any of these accidental releases. However, this analysis does estimate that potentially hazardous releases have occurred and that rupture of a UF6 cylinder represents potentially hazardous conditions for residents living adjacent to PGDP. In addition, the air dispersion models suggest that significant concentrations of uranium may have been deposited in off-site areas. Currently, we have no reports of health effects related to these accidents; however, if data become available suggesting that health effects did occur, we will re-evaluate the need for followup activities.
References
APPENDIX F:
EXPOSURE TO AIRBORNE HYDROGEN FLUORIDE
During the uranium enrichment processes at PGDP, uranium hexafluoride (UF6) is released into the air. The UF6 reacts rapidly with water in the air to form particulate uranium and fluorides, and also hydrogen fluoride gas (HF) [1]. HF is the most abundant form of atmospheric fluoride and reacts with atmospheric water to form hydrofluoric acid aerosols. Airborne particulate fluorides have low solubility and are removed from the atmosphere through dry and wet deposition.
Releases of UF6 (with atmospheric conversion to HF) occurred both as long-term releases due to process operations and as short-term releases due to accidents. Long-term (chronic) exposure to HF is evaluated based on correlation of annual UF6 releases with measured site perimeter HF concentrations. Short-term (acute) HF exposures are evaluated using accident records and air dispersion modeling.
Estimated uranium releases and ambient air monitoring results have been reported consistently throughout PGDP's operational history; fluoride releases and HF ambient air concentrations have not. Evaluation of potential HF exposures to nearby residents presents several problems: no reporting of HF release quantities or ambient air monitoring during the period of highest potential fluoride and HF emissions (1956), changes in sampling locations, and changes in the data reported (e.g., annual medians vs. means). Consequently, evaluation of chronic HF exposures during the period of highest potential emissions requires estimation or modeling of HF emissions from periods of consistent data reporting.
Uranium emissions are a good proxy for prediction of chronic or long-term HF ambient air concentrations. Ambient airborne HF concentrations were measured at several locations for the years 1961 to 1970. Comparison of mean ambient airborne HF concentrations from these locations with uranium emission estimates for the same years provides a correlation coefficient of 0.8863, which indicates a strong positive relationship between uranium emissions and measured HF concentrations at the perimeter north monitoring site (HF concentrations increase proportionately with increases in uranium emissions). That relationship is plotted in Figure F-1.
The strong correlation of uranium emissions and HF concentrations at the perimeter north station in the years where both data sets are available allows for the prediction of HF concentrations from uranium emission data in the years for which no HF monitoring data are available. These HF concentrations are predicted using the linear regression forecasting function in the computer program EXCEL (version 7.0a). Figure F-2 shows the relationships between uranium emissions (in curies per year), estimated and monitored HF concentrations at the perimeter north and one mile north stations, and measured fluoride concentrations in grass samples near the perimeter north station.
The perimeter north station consistently had the highest concentrations of both particulate uranium and HF. The perimeter north station was closer to the fluoride processing facility than other stations [2], and was downwind of the processing facility with respect to the prevailing south-southwest winds [3]. Therefore, it was assumed that this station would have had the highest concentrations of HF during the year of highest release.
All of the measured parameters show a strong relationship to uranium emissions and to the estimated HF concentrations. Figure F-2 shows measured and estimated HF ambient concentrations in relation to the Kentucky ambient air standard for average annual HF exposure (500 parts per billion, or ppb) [4] and the ATSDR provisional long-term guidance value of 12 ppb. None of the measured or estimated HF concentrations exceed the Kentucky ambient air standard.
ATSDR has established a provisional guidance value of 10 micrograms per liter (12 ppb) for annual average air concentrations of HF [5,6]. HF concentrations below 12 ppb (annual average value) are not likely to cause adverse health effects. This guidance value is more than 100 times lower than an exposure concentration that caused mild irritation to the eyes and noses of human volunteers exposed for 10 days [1]. None of the measured or estimated HF concentrations at the one north sampling station exceeded the ATSDR guidance value (Figure F-2).
Some of the estimated HF concentrations at the perimeter north station did exceed the ATSDR guidance value; the maximum value was 28 ppb (Figure F-2). The maximum annual HF emission occurred in 1956, which is the period of maximum uranium emissions. Because HF concentrations at the perimeter north station are consistently higher than at other locations, this station represents a worst-case exposure scenario. It is important to point out that no off-site residents live at the perimeter security fence. The nearest houses are closer to the one mile north and east stations than to the perimeter stations. Consequently, the concentrations at the nearest house would have been closer to the concentrations estimated by the one north station (Figure F-2) than to the concentrations at the perimeter north station. The estimated annual average HF concentrations at these points of exposure are below levels of health concern.
There is some uncertainty associated with deriving HF concentrations from uranium emissions. One measure of this uncertainty is the standard error, which is represented by error bars on the predicted HF concentrations in Figure F-2. The error bars, which show the predicted maximum and minimum HF values, do not significantly change the predicted HF concentrations with respect to the ATSDR and Kentucky health guidance values. Note that the largest standard errors occur between 1965 and 1968, the period with the highest variability and lowest uranium emissions.
In addition to the chronic or long-term process releases, accidental releases of UF6 and HF (estimated from reported UF6 releases) have occurred throughout the operating history of the PGDP facility [7,8]. The largest reported accidental release occurred in 1960, when a cylinder ruptured releasing about 11,000 pounds (approximately 5,000 kilograms) of UF6. This accident occurred in Building C-333 on November 17, 1960, at about 4:00 a.m. Another accidental UF6 release occurred during a fire at Building C-337 in December 1962. About 5,062 pounds (2,278 kilograms) of UF6 were released during this fire. Many other smaller releases have occurred, but these were at least an order of magnitude smaller than the 1960 release and less than 30% of the size of the 1962 release.
Airborne UF6 and HF concentrations surrounding PGDP from the 1960 and 1962 accidents were estimated using the RASCAL 3.0 air dispersion and dose model [9] and weather observations from the Paducah/Barkley Airport. The RASCAL model (beta test version) is used to provide a general assessment of potential HF and uranium air concentrations following accidental releases. Due to the confluence of the water vapor from PGDP cooling towers with any airborne releases, atmospheric humidity is assumed to be similar to conditions of light precipitation.
Our data on weather conditions at the time of the 1960 release indicate a stable to very stable atmosphere (stability class F), very low wind speed from the northwest, and a temperature of 39oF (dry bulb) [10]. Under these release conditions, short-term hazardous HF concentrations (6 parts per million, or ppm; 15-minute Short Term Exposure Limit) could have extended more than 1 kilometer (0.6 miles) from the release site (Building C-333) toward the southeast. This means that the estimated HF concentrations could have been at hazardous levels immediately off site. Estimated concentrations of more than 30 ppm, which is considered immediately dangerous to life/health, extended more than 500 meters (1,640 feet) from Building C-333 and would not have reached the off-site community. Table F-1 summarizes the air dispersion analysis.
According to accident records, the 1960 release occurred on November 17, 1960, at approximately 4:00 a.m. At that time of day and year, it is unlikely that nearby residents would be outside, where exposure to the maximum concentrations would occur. Air temperatures were in the 30s, so windows and doors would be shut--very little exposure to residents inside their houses probably occurred.
The explosion and fire that caused the 1962 release resulted in much greater atmospheric dispersion and much lower air concentrations and doses. This release was modeled using a fire scenario in RASCAL 3.0, which did not analyze HF dispersion. However, HF in a fire is atmospherically unstable and very unlikely to undergo significant atmospheric dispersion. Off-site HF air concentrations from this accident probably did not present a health hazard to the surrounding community.
In addition to the documented 1960 and 1962 accidents, there were community concerns about two other potential incidents: a 3-day UF6 release on March 15 through 17, 1970; and a large accidental release sometime in 1969 or 1970. A Union Carbide memorandum contained reference to a 3-day UF6 (March 15-17, 1970) that was detected via on-site air monitoring inside one of the buildings [7]. This memorandum also indicated that the average gross alpha air monitoring results for the perimeter east location for the period from October 1969 to May of 1970 were higher than normal. However, the individual weekly gross alpha air monitoring results indicated that this average was elevated for a different time period than March 15-17, 1970 [11]. The airborne fluoride results from the perimeter east location for March 1970 were not elevated. Also, the plant's original report for this incident indicated that a total of 15 grams of uranium was released inside the building and eventually released through the building ventilation system. This amount of uranium hexafluoride would not have an adverse impact off site. For the second concern (an accident that occurred in 1969 or 1970 when houses to the southeast turned black and trees died), the site accident records for the 1969/70 time frame do not report any events capable of producing significant off-site uranium or hydrogen fluoride concentrations.
However, an extensive review of the weekly air monitoring data indicate that there were several periods of elevated fluoride concentrations at perimeter air monitors during the 1969 and 1970 timeframe [11]. There is some indication that the site investigated elevated hydrogen fluoride levels to the east of the plant later in 1970, but there was no explanation of the cause. Due to the limited information available on these specific events, ATSDR cannot evaluate potential exposure doses off site. However, monitoring data do indicate that some type of release event(s) occurred that are not reflected in the accident reports reviewed.
At this time, it is not possible to determine if nearby residents were actually exposed to hazardous concentrations of uranium from any of these accidental releases. However, this analysis does indicate that potentially hazardous releases have occurred and that rupture of a UF6 cylinder represents potentially hazardous conditions for residents living adjacent to PGDP. Currently, we have no reports of health effects related to the reported accidents; however, if data become available suggesting that health effects did occur, we will re-evaluate the need for followup activities.
References
Figure F-1. Correlation Coefficient of PGDP Uranium Emissions and Hydrogen Fluoride
Measurements at the Perimeter North Station
Figure F-2. Measured and Predicted HF Concentrations at the Perimeter North and One Mile North Sampling Stations
APPENDIX G:
AIRBORNE TRICHLOROETHYLENE DISTRIBUTION AND POTENTIAL OFF-SITE EXPOSURE
Past operations at PGDP involved large quantities of trichloroethylene (TCE) as an organic solvent and degreaser. Although significant amounts of TCE were released into the groundwater system, most TCE from operational processes volatilized into the atmosphere [1]. To determine if those airborne releases present a potential for inhalation exposure to nearby residents, we conducted a TCE air dispersion analysis using the Industrial Source Complex (ISC3) model [2].
The ISC3 model uses meteorological data to generate air concentration averages, for periods from 1 hour to 1 year, for any location surrounding an air emission source. ATSDR's analysis used 1989 meteorological data from the nearby Paducah Municipal Airport (Barkley Airfield). According to data available to us, the largest annual release of TCE to the atmosphere (62,826 kilograms, or 138,845 pounds) occurred in 1986 [3]. The dispersion from this release was modeled as a single source from Building C-400--a vent 5 meters (16 feet) off the ground with a diameter of 25 centimeters (10 inches)-- and the annual release proportioned over the entire year.
For this analysis, we assumed conservative dispersion with no chemical degradation or photochemical breakdown of TCE. (Typically, TCE is estimated to degrade in the atmosphere with a chemical half-life of 3 to 7 days [4].) Under these conservative assumptions, the maximum airborne TCE concentration is 112 micrograms per cubic meter (µg/m3) for a 1-hour averaging period, and 3 µg/m3 for a 1-year averaging period, at a location 1 kilometer (0.6 miles) north of Building C-400 (that is, off site). Some animal studies have shown carcinogenic effects from TCE; however, ATSDR and EPA are re-evaluating TCE's carcinogenic effects on humans. Until TCE's carcinogenicity for humans is determined, minimal risk levels (MRLs) for non-cancerous effects are used to screen for contaminants of concern. The MRL for TCE is 10,920 µg/m3 for acute exposures (1 to 14 days) and 546 µg/m3 for intermediate exposures (15 to 365 days) [4,5]. The estimated TCE air concentrations during the highest TCE release year are two orders of magnitude lower than the MRLs and below levels of health concern. Consequently, we did not choose TCE as a contaminant of concern for airborne releases at PGDP.
References
APPENDIX H:
AIRBORNE HEXAVALENT CHROMIUM DISTRIBUTION FROM THE PGDP WATER COOLING TOWERS AND POTENTIAL OFF-SITE EXPOSURE
Isotopic diffusion operations at PGDP generate excess heat, which is released to the environment through four cooling systems. In these systems, heat exchangers transfer heat to cooling waters, which in turn release the heat to the atmosphere through 14 water cooling towers (located in four discrete areas). Until 1993, a chromium solution was added to the cooling waters to prevent corrosion [1]. This caused hexavalent chromium to be released to the atmosphere at the water cooling towers.
Although annual chromium emissions have been calculated based on the quantities of chromium compounds added to the cooling system, the airborne chromium concentration has never been measured at on-site or off-site locations. DOE has measured and modeled chromium deposition in surrounding soils and plants, and found that chromium concentrations are at background levels for locations more than 1,500 meters from the cooling towers [2,3]. However, the security fence to the east and north of the easternmost cooling systems is less than 500 meters from the towers, and the closest residence is about 1,000 meters from the towers.
Because inhalation of hexavalent chromium can be toxic, we estimated potential exposures to airborne concentrations of chromium using the ISC3 air dispersion model [4]. This model uses site-specific meteorological data (in this case, from Barkley/Paducah Municipal Airport) and a Gaussian air dispersion equation to estimate contaminant concentrations.
The 1992 chromium release of 2,015 kilograms per year (0.064 grams per second, or g/sec) was used as the emission rate for the dispersion calculations [5]. The 1992 chromium release was the highest annual emission on record, and thus represents the most conservative source term for evaluation of public health affects. To characterize local weather, we used the most recent complete meteorological data set (a 1990 hourly data set) from the EPA SCRAM Web site (http://www.epa.gov/ttn/scram/) for the Barkley/Paducah Municipal Airport weather station.
The chromium emissions were modeled as four sources, based on information from the study of cooling tower drift at PGDP [2]. Relative locations of the cooling towers were derived from Figure 1 of that study. (See Figure 2 in the main body of this report.) Chromium concentrations at breathing height were estimated for a 5,000-meter polar grid, with potential receptors located at 500-meter intervals along 16 transects (every 22.5 degrees).
The source-specific release rates and source dimensions were based on a total annual emission rate of 0.064 g/sec, allocated between the four sources [2]. The four sources were modeled as volume sources, with release heights of 8 meters and lateral dimensions of 25 meters (towers 1 and 2) and 75 meters (towers 3 and 4). Release rates were estimated as:
The model used regulatory default options and dry settling/deposition to estimate all chromium concentrations [6]. Chromium particles in the cooling tower drift have diameters of 5 to 50 microns. However, these particles are contained within water droplets that have diameters of 100 to 1,300 microns [3]. A particle size distribution of 100 to 999 microns (with a 700-micron mean) was used in calculating settling velocities.
Maximum chromium concentrations were calculated for each potential receptor for 1-hour, 8-hour, 24-hour, and 1-year averaging periods. Because wind directions and speeds change so drastically over a year, these maximum concentrations represent the highest estimated concentrations for each time period for each location. Averages for 1-hour periods are significantly higher than the 8-hour, 24-hour, or 1-year averages.
The results of this modeling indicate that dispersed hexavalent chromium air concentrations on site and off site were lower than the health guidelines for intermediate and chronic exposures [7]. The intermediate minimal risk level (MRL) for inhalation of particulate hexavalent chromium is 0.5 micrograms per cubic meter (µg/m3). The intermediate and chronic MRL for inhalation of dissolved hexavalent chromium as an aerosol is 0.1 µg/m3. The highest estimated 1-hour, 8-hour, 24-hour, and 1-year average air concentrations were on site, between the four cooling towers; they are listed in Table H-1. The maximum estimated off-site concentrations were about 500 meters north-northeast of the cooling towers, outside the security fence, and are listed below. The closest residence is approximately 1,000 meters east of the easternmost cooling system, and the estimated maximum concentrations for this location are listed below. The results of this air dispersion model are in agreement with chromium distribution studies that found no air-dispersed chromium in soil or vegetation samples beyond 1,500 meters of the cooling towers [2,3].
Table H-1. Maximum estimated airborne hexavalent chromium
concentrations
| Exposure Time | Maximum On Site | Maximum Off Site | Maximum at Closest Residence |
| 1-hour maximum | 0.0215 µg/m3 | 0.005 µg/m3 | 0.0011 µg/m3 |
| 8-hour maximum | 0.0108 µg/m3 | 0.0025 µg/m3 | 0.0005 µg/m3 |
| 24-hour maximum | 0.0067 µg/m3 | 0.0007 µg/m3 | 0.0005 µg/m3 |
| 1-year maximum | 0.0009 µg/m3 | 0.0003 µg/m3 | 0.0004 µg/m3 |
The results of this modeling study, which uses conservative assumptions for settling, dispersion, and emission rates, did not find any areas where exposure to airborne chromium exceeded health guidelines. The distribution of these airborne concentrations is supported by measurements of deposited chromium in soil and vegetation samples. Therefore, airborne hexavalent chromium was not selected as a contaminant of concern at PGDP.
References
APPENDIX I:
ATSDR GLOSSARY OF TERMS
