PETITIONED PUBLIC HEALTH ASSESSMENT
KINGS CREEK
(a/k/a FORT BELKNAP INDIAN RESERVATION/ZORTMAN MINING INCORPORATED)
LODGEPOLE, BALINE COUNTY, MONTANA
APPENDIX A: ACRONYMS/SYMBOLS AND MAPS
ATSDR |
Agency for Toxic Substances and Disease Registry |
BIA | Bureau of Indian Affairs |
BLM | Bureau of Land Management |
EMEG | Environmental Media Evaluation Guide |
IHS | Indian Health Service |
LTHA | Lifetime Health Advisory |
MCL | Maximum Contaminant Level |
MCLG | Maximum Contaminant Level Goal |
MRL | Minimal Risk Level |
ppb | Parts Per Billion |
ppm | Parts Per Million |
PRP | Potentially Responsible Party |
RMEG | Remedial Media Evaluation Guide |
USEPA | United States Environmental Protection Agency |
USGS | United States Geological Survey |
ZMI | Zortman Mining Inc. |
2 L/day | 2 liters of water per day or approximately 2 quarts or a half a gallon of water per day |
70-kg adult | 150-pound average |
Figure 1. Fort Belknap Indian Reservation: Towns and Municipalities
Figure 2. Landusky and Zortman Mines Buffer Zones, Fort Belknap Indian Reservation
Figure 3. Surface Water Drainage, Fort Belknap Indian Reservation
Figure 4. Fort Belknap Indian Reservation: Zortman and Landusky Mines
APPENDIX B: PUBLIC HEALTH CONSULTATIONS
Appendix B was not available in electronic format for conversion to HTML at the time of preparation of this document. To obtain a hard copy of the document, please contact:
Agency for Toxic Substances and Disease Registry
Division of Health Assessment and Consultation
Attn: Chief, Program Evaluation, Records, and Information Services Branch E-56
1600 Clifton Road NE, Atlanta, Georgia 30333
Source |
Date Range
|
# of Locations
|
Sampling Frequency
|
Indian Health Service (IHS) | 1990 - 1995 | 16 | Annual |
TEAM | 1995 | 2 | One time |
US Geological Survey (USGS) | 1994 | 5 | One time |
Zortman/Landusky Domestic (ZL Dom) | 1990 - 1995 | 5 | Semi-annual |
Fort Belknap Utilities | 1994 - 1995 | 6 | Annual |
B&L Industries | 1995 | 2 | One time and a followup |
Source |
Date Range
|
# of Locations
|
Sampling Frequency
|
Indian Health Service (IHS) | 1993 | 4 | One time |
TEAM | 1995 | 3 | One time |
US Geological Survey (USGS) | 1990 | 1 | Periodic January - August |
US Geological Survey (USGS) | 1994 | 5 | One time |
Fort Belknap Surface Water (FB SW) | 1994 - 1996 | 19 |
Monthly samples; not at every location each time |
Red Thunder | 1992 | 9 | One time |
Montana Department of State Lands (MDSL) | 1991 | 4 | One time |
Site Inspection (SI) | 1993 | 7 | One time |
Source | Date Range | # of Locations | Sampling Frequency |
ZMI Hard Rock Data | 7/89 | 16 Zortman and Landusky mines | One time |
Morrison-Maierie, Mill Tailings Investigation-Water soluble metals | 4/79 | 12 cross sections of Little Peoples Creek | One time |
Morrison-Maierie, Mill Tailings Investigation-Solid | 4/79 | 12 cross sections of Little Peoples Creek | One time |
Energy and Environmental Resource Consultants-Tailings Liquid (in 208 Project) | 10 & 12/78 | 4 Little Peoples Creek | One time |
Energy and Environmental Resource Consultants-Tailings solid | 10 - 12/78 | 4 Little Peoples Creek | One time |
CERT-Sediment (In Preliminary Assessment) | 1987 | 10 Little Peoples Creek | One time |
Red Thunder-Sediment | 8/91 | 8 | One time |
Morrison Knudson-Site Inspection | 5/93 | 6 (4 above Cumberland Dam; 2 below) | One time |
APPENDIX D: DIFFERENCES BETWEEN DATA SOURCES
Samples have not been collected in identical locations within each of the media (domestic drinking water, groundwater, and surface water) over time. This is a source of uncertainty for any of the conclusions reached by comparing these data.
In the various reports, metals have been reported as dissolved metals, total metals, and total recoverable metals (the same as acid extractable metals ). This means that the numbers in each report describe slightly different things. Dissolved metals are found by filtering a sample and analyzing only the liquid portion for the metals. Other methods use various means to test both the liquid and suspended matter in the samples for metals. Therefore, if a sample has metals in both the liquid portion of the sample and the suspended matter in the sample, the maximum value of metals reported in the sample will be a different number depending on which analytical method was used.
Quality Assurance/Quality Control (QA/QC)
All data provided to ATSDR was reviewed and incorporated in this document, regardless of the presence or absence of QA/QC information.
The detection levels for the surface water and groundwater data are summarized on the following pages.
Detection Levels for Groundwater Data
Contaminant | Concentration | Method | Data Set |
Aluminum | <0.1 | Dissolved | TEAM, ZL Domestic data |
<0.1 | TRC | TEAM | |
NA | USGS | ||
NA | IHS | ||
Antimony | <0.05 | Dissolved | TEAM |
NA | USGS, IHS, ZL Domestic | ||
Arsenic | ND | 206.2 | B&L Industries |
<0.005 | Dissolved | IHS 94 & 92, TEAM, ZL Domestic | |
<0.005 | Total | IHS 95, 93, 92 | |
<0.005 | Metals | IHS 91, 90 | |
<0.001 | Dissolved | USGS | |
<0.005 | TRC | TEAM | |
Beryllium | <0.001 | Dissolved | TEAM |
<0.001 | TRC | TEAM | |
NA | IHS, USGS | ||
Cadmium | <0.001 | Dissolved | IHS 94 & 92, TEAM, USGS, ZL Domestic data |
<0.001 | Total | IHS 95, 93 & 92 | |
<0.001 | Metals | IHS 91, 90 | |
<0.001 | ? | FB Utilities | |
<0.001 | TRC | TEAM | |
Chromium | <0.01 | Dissolved | IHS 94 & 92, TEAM, ZL Domestic data |
<0.01 | Total | IHS 93 | |
<0.02 | Total | IHS 92 | |
<0.02 | Metals | IHS 91, 90 | |
<0.001 | ? | FB Utilities | |
<0.001 | Dissolved | USGS | |
Copper | <0.01 | ? | FB Utilities |
<0.001 | Dissolved | USGS | |
<0.01 | Dissolved | TEAM, ZL Domestic data | |
<0.01 | TRC | TEAM | |
NA | IHS | ||
Cyanide | <0.005 | Total | IHS 90 - 95, ZL Domestic data |
<0.005 | Tot; man dist | TEAM | |
ND | 600.4 | B&L Industries | |
<0.01 | Dissolved | USGS | |
Iron | <0.03 | Metals | IHS 91, 90 |
<0.03 | Dissolved | IHS 94 & 92, TEAM, ZL Domestic data | |
<0.03 | Total | IHS 95, 93, & 92 | |
<0.01 | ? | FB Utilities | |
<0.03 | TRC | TEAM | |
<0.003 | Dissolved | USGS | |
Lead | <0.005 | Metals | IHS 91, 90 |
<0.01 | Metals | IHS 90 | |
<0.005 | Total | IHS 95 & 93 | |
<0.01 | Total | IHS 92 | |
<0.01 | Dissolved | IHS 94 & 92, TEAM, ZL Domestic data | |
<0.001 | ? | FB Utilities | |
? | 239.2 | B&L Industries | |
<0.01 | TRC | TEAM | |
<0.001 | Dissolved | USGS | |
Manganese | <0.01 | Dissolved | IHS 94& 92, TEAM |
<0.01 | Total | IHS 93 | |
<0.02 | Total | IHS 92 | |
<0.02 | Metals | IHS 91 | |
<0.005 | ? | FB Utilities | |
<0.01 | TRC | TEAM | |
<0.02 | Dissolved | ZL Domestic data | |
Nitrate/Nitrite | <0.05 | as N | IHS 95, 94, 92,TEAM, ZL Domestic data |
<0.05 | dissolved NO2+NO3 | USGS | |
Nitrate | <0.05 | as N | IHS 93, 92, 91, 90 |
Selenium | <0.005 | Dissolved | IHS 94, 92, TEAM, ZL Domestic data |
<0.001 | ? | FB Utilities | |
<0.005 | Total | IHS 95,93, 92 | |
<0.005 | Metals | IHS 91, 90 | |
<0.005 | TRC | TEAM | |
<0.001 | Dissolved | USGS | |
Zinc | <0.01 | Dissolved | TEAM |
<0.01 | Total | TEAM | |
<0.003 | Dissolved | USGS | |
NA | IHS, FB Utilities |
Detection Levels for Surface Water Data
Contaminant
|
Concentration
|
Method
|
Data Set
|
Aluminum |
<0.01
|
200.7
|
FB SW |
0.026 U
|
CHECK SAMPLING PLAN
|
SI | |
<0.1
|
TRC
|
TEAM | |
NA
|
|
USGS 90 & 94, IHS, MDSL | |
Antimony |
<0.05
|
200.7
|
FB SW |
<0.05
|
Dissolved
|
TEAM | |
<0.05
|
TRC
|
TEAM | |
0.026 U
|
CHECK SAMPLING PLAN
|
SI | |
NA
|
|
USGS, IHS, MDSL | |
Arsenic |
<0.005
|
206.3
|
FB SW |
<0.001
|
Dissolved
|
USGS | |
0.001 U
|
CHECK SAMPLING PLAN
|
SI | |
<0.005
|
Total
|
IHS | |
<0.005
|
Dissolved
|
TEAM | |
<0.005
|
TRC
|
TEAM | |
?
|
|
MDSL | |
Beryllium |
<0.005
|
200.7
|
FB SW |
<0.001
|
TRC
|
TEAM | |
<0.001
|
Dissolved
|
TEAM | |
<0.01
|
TRC
|
USGS | |
NA
|
|
IHS | |
Cadmium |
<0.005
|
200.7
|
FB SW; IHS |
<0.001
|
TRC
|
TEAM, MDSL, USGS 90 | |
<0.001
|
Dissolved
|
USGS 94, TEAM | |
0.004 U
|
CHECK SAMPLING PLAN
|
SI | |
<0.001
|
?
|
Red Thunder | |
Chromium |
<0.02
|
200.7
|
FB SW, MDSL |
<0.01
|
TRC
|
TEAM | |
<0.01
|
Dissolved
|
TEAM | |
<0.03
|
?
|
Red Thunder | |
<0.001
|
Dissolved
|
USGS 94 | |
0.005 U
|
CHECK SAMPLING PLAN
|
SI | |
<0.001
|
TRC
|
USGS 90 | |
<0.01
|
Total
|
IHS | |
Copper |
<0.02
|
200.7
|
FB SW |
<0.01
|
TRC
|
TEAM, MDSL | |
<0.001
|
?
|
Red Thunder | |
<0.001
|
Dissolved
|
USGS | |
0.005 U
|
CHECK SAMPLING PLAN
|
SI | |
<0.01
|
Total
|
IHS | |
Cyanide |
<0.005
|
335.2
|
FB SW |
<0.05
|
Man'l Dist
|
TEAM | |
<0.01
|
Dissolved
|
USGS | |
0.010 U
|
CHECK SAMPLING PLAN
|
SI | |
<0.005
|
Total
|
MDSL | |
NA
|
|
USGS 90 | |
Iron |
<0.05
|
200.7
|
FB SW |
<0.03
|
TRC
|
TEAM | |
<0.03
|
TRC
|
TEAM | |
?
|
|
IHS, USGS 90 & 94, SI | |
NA
|
|
MDSL | |
Lead |
<0.05
|
200.7
|
FB SW |
<0.01
|
TRC
|
TEAM, MDSL | |
<0.01
|
Dissolved
|
TEAM | |
<0.005
|
Total met
|
IHS | |
<0.001
|
Dissolved
|
USGS 94 | |
0.001 U
|
CHECK SAMPLING PLAN
|
SI | |
<0.01
|
?
|
Red Thunder | |
?
|
|
USGS 90 | |
Manganese |
<0.02
|
200.7
|
FB SW |
<0.01
|
TRC
|
TEAM, MDSL | |
<0.01
|
Dissolved
|
TEAM | |
<0.01
|
Total
|
IHS | |
?
|
|
USGS 90 & 94 | |
Nitrate |
<0.05
|
353.2
|
FB SW |
<0.1
|
Total
|
USGS 90 | |
<0.5
|
?
|
MDSL | |
<0.05
|
Dissolved; as N
|
USGS 94 | |
<0.05
|
as N
|
TEAM | |
NA
|
|
SI | |
Selenium |
<0.005
|
270.3
|
FB SW |
<0.005
|
TRC
|
TEAM, MDSL | |
<0.001
|
Dissolved
|
USGS 94 | |
0.002 U
|
CHECK SAMPLING PLAN
|
SI | |
<0.001
|
Total
|
USGS 90 | |
<0.005
|
Total
|
IHS | |
Sodium |
<1
|
200.7
|
FB SW |
?
|
|
USGS 90 & 94, SI, MDSL, IHS | |
NA
|
|
TEAM | |
Zinc |
<0.02
|
200.7
|
FB SW |
<0.01
|
TRC
|
TEAM, USGS 90 | |
<0.01
|
Dissolved
|
TEAM | |
<0.003
|
Dissolved
|
USGS 94 | |
<0.01
|
Total
|
IHS | |
?
|
|
SI, MDSL |
ATSDR comparison values are media-specific concentrations considered to be "safe" under default conditions of exposure. They are used as screening values in the preliminary identification of "contaminants of concern" at a site. As ATSDR uses the phrase, a "contaminant of concern" is merely a site-specific chemical substance that the health assessor has selected for further evaluation of potential health effects; the term does not imply any level of hazard. Generally, a chemical is selected as a contaminant of concern because its maximum concentration in air, water, or soil at the site exceeds one of ATSDR's comparison values. This approach is conservative by design. If enough data were available, actual exposures could be estimated more accurately using the average concentration or a range of concentrations.
It cannot be emphasized strongly enough that comparison values are not thresholds of toxicity. Although concentrations at, or below, the relevant comparison value may reasonably be considered safe, it does not automatically follow that any environmental concentration that exceeds a comparison value would be expected to produce adverse health effects. In fact, the whole purpose behind highly conservative, health-based standards and guidelines is to enable health professionals to recognize and resolve potential public health problems before they become actual health hazards. The probability that adverse health outcomes will actually occur depends on site-specific conditions and individual lifestyle and genetic factors that affect the route, magnitude, and duration of actual exposure, and not on environmental concentrations alone.
Listed below are the abbreviations for selected comparison values and units of measure used in this document. Brief descriptions of the various comparison values that ATSDR uses to select chemicals for further evaluation follow this list.
Comparison Values (in alphabetical order):
AL |
EPA Drinking Water Action Level. |
child RMEG | Reference Dose Media Evaluation Guide for a child (see RMEG below for more detail) |
EMEG | Environmental Media Evaluation Guide |
EPA SLG | EPA Soil Lead Guidance |
MCL | Maximum Contaminant Level |
pMCL | proposed Maximum Contaminant Level |
RBC | Risk-Based Concentration |
RMEG | Reference Dose Media Evaluation Guide |
sMCL | secondary Maximum Contaminant Level |
USGS | United States Geological Survey |
WHO | World Health Organization |
Action Level (AL) is the concentration for lead defined in the Safe Drinking Water Act.
Environmental Media Evaluation Guides (EMEG) are concentrations that are calculated from ATSDR minimal risk levels by factoring in default body weights and ingestion rates.
EPA Soil Lead Guidance (EPA SLG) is the revised interim soil lead guidance for CERCLA and RCRA corrective action facilities; it is presented in OSWER Directive 9355.4-12, issued July 1994.
Maximum Contaminant Levels (MCLs) are legally enforceable drinking water standards promulgated by the EPA. These are contaminant concentrations in drinking water that EPA deems protective of public health, considering the availability and economics of water treatment technology, over a lifetime (70 years), at an exposure rate of 2 liters of water per day for an adult.
proposed Maximum Contaminant Levels (pMCLs) are nonenforceable drinking water standards proposed by the EPA, but not finalized in a regulation.
Risk-Based Concentrations (RBC) are derived by the Region III Office of the Environmental Protection Agency. They represent levels of contaminants (noncarcinogens and carcinogens, when applicable) in air, water, soil, and fish that are considered safe, assuming default values for body weight, exposure duration, and ingestion and inhalation rates.
Reference Dose Media Evaluation Guide (RMEG) is the concentration of a contaminant in air, water, or soil that ATSDR derives from EPA's reference dose (RfD) for that contaminant by factoring in default values for body weight and intake rate. Different RMEGs are calculated for adults and children; this report uses values calculated for a child.
secondary Maximum Contaminant Levels (sMCLs) are legally enforceable standards set by EPA for contaminants that are not directly associated with health problem, but cause unpleasant aesthetic qualities in drinking water.
United States Geological Survey (USGS) finished water quality in public water supplies benchmark, cited in: The Water Encyclopedia, 2nd ed., Lewis Publishers, 1990, Table 6-26, p. 446.
United States Geological Survey (USGSb) health-based concentration for persons on a sodium-limited diet.
World Health Organization (WHO) guideline for aesthetic quality is 200 mg/l for a substance. The 20 mg/l guideline for sodium is based on a level acceptable for people on a sodium-limiting diet.
Units of Measure:
ppm | = parts per million (mg/L water or mg/kg soil). |
ppb | = parts per billion (µg/L water or µg/kg soil). |
kg | = kilogram (1,000 grams) |
mg | = milligram (0.001 grams) |
µg | = microgram (0.000001 grams) |
L | = liter |
m3 | = cubic meter (used in reference to a volume of air equal to 1,000 liters) |
mg/L | = milligrams per liter |
µg/L | = micrograms per liter |
mg/kg | = milligrams per kilogram |
µg/kg | = micrograms per kilogram |
References
Health Assessment Guidance Manual. Agency for Toxic Substances and Disease Registry, Atlanta, GA, 1992.
Drinking Water and Health, Vol. 3, National Academy Press, Washington, D.C., 1980.
EPA Region III Risk-Based Concentration Table, January-June 1996. United States Environmental Protection Agency, Region III, 841 Chestnut Street, Philadelphia, PA 19107. Available on EPA Region III's Internet website:
van der Leeden F., Troise F.L., and Todd, D.K. 1990. The Water Encyclopedia, 2nd ed., Lewis Publishers: Chelsea, MI.
APPENDIX F: ATSDR's RESPONSE TO COMMENTS
Comments received during the public comment period for the Fort Belknap Indian Reservation/Zortman Mining Incorporated site and ATSDR's response to those comments are listed below. The comments are italicized, with ATSDR's response directly below.
1. Talking about the Grinnell Agreement of 1896 in the Background section of the public health assessment is only used to make the public feel "bad" for the tribes and "hate" the white man and industry. This portion sets a bad mood for the reader going into the document.
In public health assessments, ATSDR typically discusses the site's history and ownership in the Background section of the document, if such information is available. Ownership of a site may change several times over the course of years. ATSDR's intent in including information from the Grinnell Agreement was only to provide the reader with background information about the area and site history.
2. The Historic section seems to be unrelated to public health issues and appears more of an attempt to question the appropriateness of federal government actions from one hundred years ago. Because this historic account differs in detail from other versions of the area history, citable documentation should be clearly distinguished from personal opinions. For example, is your reference that the tribes vehemently opposed the "sale of the mountains" documented fact, or rather, more recent hearsay? Should there be a discussion of the 1895 value of $360,000? Is it true that, on the same visit to Montana Territories that resulted in the sale of this relatively small portion of the Little Rockies formalized in the Grinnell Agreement, the same commissioners also established Glacier National Park, and that both agreements were thought to be in the public interest?
As noted in the previous comment, ATSDR typically discusses available site history information in the Background section of the public health assessment. When appropriate, ATSDR staff reference the historic information provided to the Agency. Please refer to the historic section to note the information that has been referenced. The actual dates (i.e., 1895) are provided to put historic information in perspective and no further information is deemed necessary. The establishment of Glacier National Park is not relevant to this public health assessment.
3. In the context of this discussion and to make this historical setting relate to current health concerns, it would seem appropriate to include a discussion of possible shortcomings of the reservation system that may directly relate to the statistically high occurrences of substance abuse and other health problems as documented by the Indian Health Service. Does the high rate of unemployment (reported to be 85%) or other social problems on the Fort Belknap Indian Reservation result in anxiety, which could result to chronic health problems? These issues seem to relate much more directly to public health concerns.
Discussions of the possible shortcomings of the reservation system are out of the scope of this public health assessment. ATSDR staff did account for issues that may relate to public health in other sections of the public health assessment. For example, on the bottom of page 23, ATSDR states that "excessive tiredness and fatigue can be caused by the chronic anxiety that may be associated, in this case, with fear of potential exposures to chemical contaminants, the possibility of mine closure and continuing layoffs, long working hours, and driving long distances."
4. Further groundwater studies are to be conducted; therefore, isn't your report somewhat premature, as the groundwater studies have not been conducted?
As stated in the Preface to the document, "The ATSDR Public Health Assessment: A Note of Explanation," ATSDR acknowledges that this document represents the Agency's best efforts, based on currently available information, to provide the community with an evaluation of the site's health implications within a limited time frame. As new data become available (i.e., groundwater data), ATSDR will modify the conclusions and recommendations for this site, if appropriate.
5. Page 17, fourth paragraph: "The maximum concentrations from domestic well data compared between 1990-1995 and 1978", your report stated the levels were slightly higher (10-35%). I believe 35% is significantly higher. Also, your report did not mention the increase in arsenic levels from 1978 data compared to 1990-1995 data (Table 3). If these levels are going to continue to increase in the future, at what level are they going to reach? Groundwater moves very slowly through the aquifers, are these "slightly high values" just the beginning of the increase in values that could show up in the future?
As stated in the public health assessment, the increases for specific conductivity, TDS, and sulfate do not appear to be out of the ordinary in view of the fact that historically the concentrations have been high. Therefore, ATSDR does not consider the levels to be "significantly" higher. ATSDR cannot predict future levels of contamination; however, the public health assessment indicated that the other substances (including arsenic) in the domestic well samples appear to be isolated detections and represent no apparent trends or pattern of groundwater contamination.
6. The draft public health assessment contains many unconditional statements regarding health risks to the Tribes that are based on unreliable information or incomplete analysis.
ATSDR has previously responded to this comment. Please refer to page 24 for a response to this comment.
7. The data sets used for this public health assessment are flawed. Some of the data is 18 years old, and apparently none was collected for the purposes of a public health study. Approximately two-thirds of the data sets resulted from one-time sampling events. A variety of different entities collected the data, and the samples were tested using a variety of analytical methods.
ATSDR has previously responded to this comment. Please refer to page 6 (Statement of Issues section) and the information contained in Appendix C and Appendix D.
8. The public health assessment makes only vague reference to data quality and says nothing about the effects of data quality on the report's validity.
ATSDR has previously responded to this comment. Please refer to page 6 (Statement of Issues section) and the information contained in Appendix C and Appendix D.
9. Because the ATSDR prepared this public health assessment without generating its own environmental quality data, under controlled conditions, the ATSDR was forced to draw conclusions, often crucial ones, from data of questionable quality.
As stated in the Preface to the document, "The ATSDR Public Health Assessment: A Note of Explanation," ATSDR acknowledges that in preparing this document, ATSDR has collected relevant health data, environmental data, and community health concerns from the Environmental Protection Agency (EPA), state and local health and environmental agencies, the community, and potentially responsible parties, where appropriate. For this public health assessment, ATSDR obtained a majority of the data from the Bureau of Land Management and ZMI's Environmental Impact Statement. ATSDR does not collect its own data solely for the purpose of public health assessments. ATSDR has included statements in our report in reference to the quality of the data. Please refer to page 6 (Statement of Issues section) and the information contained in Appendix C and Appendix D.
10. The report contains conclusions about health effects of nearby mining activity and discusses trends in the data with no mention of the level of confidence upon which its conclusions rest.
ATSDR has previously responded to this comment. Please refer to page 6 (Statement of Issues section) and the information contained in Appendix C and Appendix D.
11. The final report must also treat water quality and community health as the complex issues they are. The lives of Fort Belknap residents are affected by a myriad of influences that act in combination over many years. The residents do not have the luxury of eliminating, piecemeal, these factors from their lives, and neither should the ATSDR analysis of these factors.
The ATSDR public health assessment is a report that addresses the likelihood that exposure to contaminants at the maximum concentrations detected would result in adverse health effects. To accomplish this, ATSDR evaluates each chemical of concern accounting for various factors. While the relative toxicity of a chemical is important, the response of the human body to a chemical exposure is determined by several additional factors: the concentration (how much); the duration of exposure (how long); and the route of exposure (breathing, eating, drinking, or skin contact). Lifestyle factors (i.e., occupation and personal habits) have a major impact on the likelihood, magnitude, and duration of exposure. Individual characteristics such as age, sex, nutritional status, overall health, and genetic constitution affect how a human body absorbs, distributes, metabolizes, and eliminates a contaminant. A unique combination of all these factors will determine the individual's physiologic response to a chemical contaminant and any adverse health effects the individual may suffer as a result of the chemical exposure. The ATSDR public health assessment attempts to address all of these various factors; hence, ATSDR has not eliminated the myriad of influences that affect Fort Belknap residents from our evaluation.
12. The report should indicate where further data sampling is called for. The ATSDR is aware that a community health evaluation will be performed on the reservation as a supplemental environmental project. Explicit recommendations from ATSDR for new research could make this upcoming project more efficient and provide more useful information to all parties.
As the commenter states, ATSDR is aware of the supplemental environmental project. In fact, ATSDR staff provided input into the original project design and focus. Currently, ATSDR has been informed that the supplemental environmental project is on hold because ZMI filed for bankruptcy on January 15, 1998 in Reno, Nevada. If the project is resumed, ATSDR agrees to provide further assistance as needed in this effort.
13. This study has been done more than once. The same conclusions keep coming back. It is time to stop the expensive studies and very publicly show and admit that there are no health problems from ZMI.
ATSDR's mission is to "prevent exposure and adverse human health effects and diminished quality of life associated with exposure to hazardous substances from waste sites, unplanned releases, and other sources of pollution present in the environment." ATSDR was petitioned in September 1995, by the Fort Belknap Community Council, and is under mandate by Congress to respond to all petition requests. If future requests to review and evaluate additional data are received, ATSDR will respond accordingly by providing the petitioner with whatever public health activities are deemed appropriate.
14. The reference to the "water violation settlement" in the conclusion section is factually incorrect. A correct reference would be: the Consent Decree resulting from the lawsuit settlement.....
Please refer to the main text in the conclusion section for this change.
15. The fourth conclusion does not reflect the data and discussions presented in the body of the report. There is a wealth of compelling evidence pointing to a conclusion that water in the private wells is exactly what would be expected, given the aquifer characteristics of the geologic units in which these wells are completed. There does not appear to be any evidence whatsoever, of a mine affect on these wells. For example, on page 16 you have included an applicable citation: Data collected in the southwest portion of the Fort Belknap Indian Reservation going back to 1936 indicate these same elevations of these same parameters [iron, manganese, TDS, and sulfate] (Feltis 1983). More recent data to the present suggests that these same parameters remain naturally elevated when compared to other aquifers more suitable to drinking water. Considering that this health assessment was petitioned based, to a large degree, on allegations of mining effects on reservation well water quality, it would seem appropriate that the conclusion reflect the data review. We propose the following revision: "Private wells on the reservation also contain aesthetically unappealing levels of iron, manganese, sodium, sulfate, total dissolved solids, specific conductivity, and pH. On the basis of the data reviewed by ATSDR, the levels of these constituents appear to be the result of natural conditions."
As stated throughout the public health assessment main text and in the health consultations contained in Appendix B, ATSDR concurs that the levels of constituents in groundwater appear to be naturally occurring. However, as stated in conclusion four, "it is not possible to conclusively determine whether these elevated levels are naturally occurring or related to contamination from the mine." ATSDR indicated under the section "Legal Actions" in the Background section of the Public health assessment that the settlement required a "Ground Water Study Plan, which will provide the information needed to determine whether or not there are impacts from mine wastewater on the area groundwater."
16. Clearly, in reference to conclusion five, natural biologic contamination is, by far, the most likely health risk in consuming water from springs and seeps, as would be the case in most mountainous areas. Unless otherwise documented, this risk should be better clarified.
ATSDR addresses biologic contamination on page 19 of the public health assessment. ATSDR stated that King Spring has been posted as a biologic hazard. Because the Agency focuses, for the most part, on "chemical contamination" and not "biologic contamination," our conclusions center around adverse health effects, if any, that could be associated with exposures to chemical contamination. As stated in conclusion five, the exposures to springs and seeps are expected to be infrequent and would not result in adverse health effects in adults or children.