PUBLIC HEALTH ASSESSMENT CONROE CREOSOTING COMPANY
CONROE, MONTGOMERY COUNTY, TEXAS November 23,2004
The Texas Department of Health
Under a Cooperative Agreement with the
Agency for Toxic Substances and Disease Registry
TABLE OF CONTENTS
Site Description and History
Land Use and Natural Resource Use
Community Health Concerns
Health Outcome Data
Children's Health Considerations
Public Health Action Plan
Authors, Technical Advisors, and Organizations
The Texas Department of Health (TDH) and the Agency for Toxic Substances and Disease Registry (ATSDR) have concluded that exposure to the soil and sediment downstream of the CCC site in and along Stewart's Creek and Little Caney Creek poses no apparent public health hazard to adults or children because contaminants are not present at levels expected to cause a health problem or because people are unlikely to come into contact with contaminated sediments in enough frequency or duration to result in health problems under current circumstances.
In the past, contamination in on-site soil and sediment may have posed a public health hazard. In 2002 2003, the U.S. Environmental Protection Agency (EPA) took action to remove contaminated soil on the site and contaminated sediment along Stewart's Creek; therefore, exposure to on-site soil and sediment no longer poses a potential threat to public health.
Because EPA has removed and contained contaminated soil, sediment, and materials from the site, including the former drainage ditch, surface water is no longer a potential threat to public health. Consequently, TDH and ATSDR have classified the exposure to surface water on the site or from Stewart's Creek adjacent to the CCC site as posing no public health hazard.
TDH and ATSDR previously concluded that the drinking water on the CCC site and in the vicinity poses no public health hazard to children or adults who may use the water for drinking or other household uses. Affected groundwater has not migrated off-site and water from groundwater monitoring wells at the CCC site is not used for drinking or other household uses. Therefore, TDH and ATSDR have concluded that on-site groundwater from the monitoring wells poses no apparent public health hazard.
Due to a lack of available air data while the site was operating, past exposure to contaminants in the air could not be evaluated and has been classified by TDH and ATSDR as posing an indeterminate public health hazard. Current releases to the air are prevented from occurring by the cap of the Resource Conservation and Recovery Act (RCRA) vault that consists of a layer of high-density polyethylene and a layer of 3-foot thick compacted clay. Therefore, TDH and ATSDR have classified current exposure to air on the CCC site and in the vicinity as posing no public health hazard.
Contaminants have been contained and are no longer migrating from the site, although the fish have not been tested. In addition, the nearest fishable, downstream waterway is at least 6 miles from the site. Therefore, eating fish caught downstream from the CCC site is not likely to pose a current or future public health hazard.
In conducting the PHA, three types of information are used: environmental data, community health concerns, and health outcome data. The environmental data are reviewed to determine whether people in the community might be exposed to hazardous materials from the NPL facility. If people are being exposed to these chemicals, ATSDR will determine whether the exposure is at levels that might cause harm. Community health concerns are collected to determine whether health concerns expressed by community members could be related to exposure to chemicals released from the facility. If the community raises concerns about specific diseases in the community, health outcome data (information from state and local databases or health care providers) can be used to address the community concerns. Also, if ATSDR finds that harmful exposures have occurred, health outcome data can be used to determine if illnesses are occurring that could be associated with the hazardous chemicals released from the NPL facility.
In accordance with an Interagency Cooperative Agreement, ATSDR and TDH have prepared this PHA for the Conroe Creosoting Company site. This PHA presents conclusions about whether exposures are occurring, and whether a health threat is present. In some cases, exposures can be determined to have occurred in the past; however, often a lack of appropriate historical data makes it difficult to quantify past exposures. If a threat to public health exists, recommendations are made to stop or reduce the threat to public health.
|ATSDR PUBLIC HEALTH CONCLUSION CATEGORIES|
|CATEGORY A. |
URGENT PUBLIC HEALTH
This category is used for sites where short-term exposures (< 1 yr) to hazardous substances or conditions could result in adverse health effects that require rapid intervention.
Evaluation of available information2 indicates that site-specific conditions or likely exposures have had, are having, or are likely to have in the future, an adverse impact on human health and requires immediate action or intervention. Such site-specific conditions or exposures might include the presence of serious physical or safety hazards, such as open mine shafts, poorly stored or maintained flammable/explosive substances, or medical devices which, upon rupture, could release radioactive materials.
|CATEGORY B. |
PUBLIC HEALTH HAZARD1
This category is used for sites that pose a public health hazard due to the existence of long-term exposures(> 1 yr) to hazardous substances or conditions that could result in adverse health effects.
Evaluation of available relevant information2 suggests that, under site-specific conditions of exposure, long-term exposures to site-specific contaminants (including radionuclides) have had, are having, or are likely to have in the future, an adverse impact on human health that requires one or more public health interventions. Such site-specific exposures might include the presence of serious physical hazards, such as open mine shafts, poorly stored or maintained flammable/explosive substances, or medical devices, which, upon rupture, could release radioactive materials.
|CATEGORY C. |
INDETERMINATE PUBLIC HEALTH HAZARD
This category is used for sites in which critical data are insufficient with regard to extent of exposure and/or toxicologic properties at estimated exposure levels.
The health assessor must determine, using professional judgment, the criticality of such data and the likelihood that the data can be obtained and will be obtained in a timely manner. Where some data are available, even limited data, the health assessor is encouraged to the extent possible to select other hazard categories and to support their decision with clear narrative that explains the limits of the data and the rationale for the decision.
|CATEGORY D. |
NO APPARENT PUBLIC
This category is used for sites where human exposure to contaminated media might be occurring, might have occurred in the past, and/or might occur in the future, but the exposure is not expected to cause any adverse health effects.
Evaluation of available information2 indicates that, under site-specific conditions of exposure, exposures to site-specific contaminants in the past, present, or future are not likely to result in any adverse impact on human health.
NO PUBLIC HEALTH HAZARD
This category is used for sites that, because of the absence of exposure, do NOT pose a public health hazard.
Sufficient evidence indicates that no human exposures to contaminated media have occurred, none are now occurring, and none are likely to occur in the future.
| 1 Each of these designations represent a professional judgment made in any given case on the basis of critical data that ATSDR regards as sufficient to support a decision. It does not imply, however, that the available data are necessarily complete; in some cases, additional data may be required to confirm or further support the decision.|
2 Examples include environmental and demographic data; health outcome data; community health concerns information; toxicologic, medical, and epidemiologic data.