ATSDR - PHA - Malvern TCE Site, Malvern, Chester County, Pennsylvania

PUBLIC HEALTH ASSESSMENT

MALVERN TCE SITE
MALVERN, CHESTER COUNTY, PENNSYLVANIA

APPENDICES

A. Figures

Figure 1. Site Vicinity Map

Figure 2. Geological Faults

Figure 3. Plant Area

Figure 4. Surface Soil Sampling Locations

Figure 5. Groundwater Table Map

Figure 6. Groundwater Table Map

Figure 7.

Figure 8. Soil Boring Locations-Plant Area

Figure 9. Soil Boring Locations Former Disposal Area (FDA)

B. Attachment

PUBLIC COMMENTS AND RESPONSE

The following are responses to comments received in a letter dated May 5, 1993, from a private citizen living near the Malvern TCE site.

Comment: Why were some drums allowed to stay on site after partial cleanup of soils?

Response: This report has been corrected to indicate that all drums originally inside the FDA were removed. Some drums that contain unknown materials from other areas of the site are still on site. Sometimes PADER or EPA will allow drums that contain material left from well drilling or soil boring operations to be "staged," or kept, on the site until appropriate removals can take place. Sometimes drums that contain non-hazardous materials are allowed to remain on site. EPA or PADER will have to tell you exactly what material is in the drums and why some drums were allowed to remain after partial cleanup of the soils.

Comment:
Is Chemclene still a solvent recycler as the reports states?

Response:
According to PADER, Chemclene now recycles only non-hazardous chemicals. However, some solvents are still stored on site and, apparently, the sale of solvents continues. The report has been changed to clarify this point.

Comment:
The writer claims to have furnished information to a member of the health assessment team regarding filter maintenance on residential wells. The report states that details of such maintenance are unknown to PADOH.

Response: Descriptions of filter maintenance and water sampling frequency vary from person to person in the community. The information provided to Mr. Schmeer of PADOH was given during a public availability meeting for the Foote Mineral site, after the Chemclene report was first drafted. The report has been changed to indicate that filters are replaced approximately yearly.

Comment:
The writer is interested in seeing a year by year groundwater quality comparison based upon sampling results.

Response:
The information desired is not available on a yearly basis (see Page 11 of the report). PADOH has recommended that such sampling be conducted.

Comment: When were the maximum concentrations of TCE and TCA detected? Does the writer correctly understand that PCE appeared in a well 2,500 feet southwest of the site?

Response: The maximum level of TCE occurred in 1983 and the maximum level for TCA occurred in 1982 in the same well. The report has been changed to include the dates. Also, you are correct in noting that PCE has been found in a well 2,500 feet southwest of the site.

Comment: Could the State Health Data Center possibly just take the list of 31 cancer deaths due to "other and unspecified types of cancer" which has the statistically significant SMR of 1.632 and at least determine what those "other" causes were?

Response: The 31 cancer deaths due to "other and unspecified types of cancer" can be obtained from the computer files for the eleven year period 1980-1990. This would be of considerable computer cost and staff time expense. Eleven separate data files would have to be accessed after a formal request with justification of why such information was required. The Health Assessment team does not feel this would be fruitful. The 1990 Pennsylvania Vital Statistics Report (see attached data) indicates there were 3,145 deaths in Pennsylvania in the category "Malignant neoplasm of other and unspecified sites," International Classification of Disease (ICD) code 190-199. The state numeric breakdown by cancer site was as follows:

ICD Code number of deaths

190 eye
9

191 brain 642

192 other and unspecified parts of nervous system
11

193 thyroid gland
65

194 other endocrine glands and related structures 26

195-199 other underspecified sites
2,392

TOTAL 190-199
3,145

Seventy-six percent of the deaths in this category are attributable to other and unspecified sites. These are contained in ICD code 199 which simply indicates general carcinoma site unspecified. If this proportion holds true for East Whiteland Township, approximately 24 of the 31 cancer deaths would be of this nature.

Comment:	Have you looked at the 1991 mortality figures yet?
Response:	Yes. There was nothing unusual in the 1991 cancer mortality (total and eight selected sites). There were eighteen cancer deaths and 79 total deaths. (22.7% of deaths to cancer compared to 24.5% in Pennsylvania for 1991).
Comment:	The Cancer Registry "has no meaningful data."
Response:	There are problems. The cancer registry is experiencing more geocoding problems (coding the actual place of residence) than the mortality file which has been established for decades. The mobility of the cancer patients and the possibility of being treated at several hospitals adds to this difficulty. Also, the data are developed for larger-based studies, such as county as compared to state rates, rather than comparing smaller populations, such as near a hazardous waste site as compared to county rates. This is a universal problem. Statistically, comparisons of such small populations are very difficult to do. However, trends in neighborhoods may be established.
Comment:	The report recommends that residents whose wells have been contaminated be provided with appropriate treatment systems. Chemclene should be given credit for already providing carbon filters. Even the nearby public supply well has low level contamination.
Response:	The recommendation to provide residents with acceptable water is valid. This report does state that Chemclene has provided filter systems for private wells where the levels of contaminants exceed MCLs. However, as new wells are drilled and the changing hydrogeologic conditions continue, contamination could spread to other wells or levels in currently contaminated wells could increase. Also, for contaminants that are possible human carcinogens, MCLs may not be appropriate criteria to use for determining which water wells should be treated. In the future, another water source may be required if contamination spreads or levels increase in drinking water supplies.
Comment:	The report states that not enough monitoring wells exist. Were not EPA and PADER responsible for seeing that proper monitoring of groundwater was accomplished?
Response:	The report states correctly that an insufficient number of monitoring wells are in place to characterize the plume three dimensionally. This is especially true for off-site areas. This is PADOH's opinion, and this document offers explanations as to why that is true. This document provides that opinion to PADER and EPA. Those agencies will review the situation and determine if more monitoring wells will be drilled.
Comment:	The report states that there is uncertainty in the scientific community regarding the carcinogenicity of TCE to humans. Based upon the report, the writer feels that no great enlightenment is likely to occur as far as public health education is concerned.
Response:	Community health education is designed to assist the community, that live near the site, in understanding their potential for exposure, in assessing adverse health occurrence in the community or talking about exposures with their health care providers, and in preventing or diminishing exposure to hazardous substances. Such activities may include disseminating written materials or making data base information available, or other activities the community feels would be helpful. Although science has not yet established what health conditions may or may not occur because of exposure at certain levels, the community can be told how to avoid or lessen exposures.
Comment:	How was the well numbering system determined for Hillbrook Circle?
Response:	PADOH does not know why the home numbering sequence was established as it was.
Comment:	When was the TCE subregistry initiated? How many persons are on the subregistry? Who uses the subregistry? Does it show any trends?
Response:	Data collection for the TCE subregistry began in Summer 1989. The baseline number of people included was 4,281, of which 4,042 are still living. The files are created and maintained by ATSDR. ATSDR does not release any information that contains personal identifiers; however, anyone can request general information that does not involve personal identifiers. Trends have been reported. Those trends cannot be linked to TCE exposure as the cause of any illnesses reported; however, those trends can lead to epidemiology or other studies that may help further our knowledge about exposures to TCE. Those reports and other pertinent information regarding the TCE subregistry can be obtained by writing to Exposure and Disease Registry Branch, ATSDR, Mail Stop E31, 1600 Clifton Road, N.E., Atlanta, GA 30333.
Comment:	Nowhere does the report state that Chemclene is a RECRA [sic] site.
Response:	The correct abbreviation is RCRA (Resource Conservation and Recovery Act), which covers hazardous waste generators (past and current) that are still operating. Whether RCRA or Superfund regulations apply is irrelevant to the public health assessment, although the distinction is important in regulatory activities. The focus of the public health assessment is to determine what public health actions need to be implemented to help the community stop or avoid exposure to contamination. The public health assessment also offers recommendations to EPA and PADER that will, hopefully, be considered when cleanup activities are begun.
Comment:	The individual would like more information about the effects of TCE on the nervous system. Who made the studies? Where? When?
Response:	The information is available in ATSDR's Toxicological Profile for TCE. A copy of the toxicological profile may be obtained by writing to the Division of Toxicology, ATSDR, Quality Assurance Branch, 1600 Clifton Road, N.E., Mail Stop E29, Atlanta, GA 30333.

The following are responses to comments received by ATSDR from the owner of Chemclene.

Comment: We were unaware that the public health assessment was available for public comment until it was too late to respond. This occurred despite a request to receive a copy of the document. Also a 30-day comment period is not enough time.

Response:
The availability of the document for public comment was announced through normal channels, which includes advertisements in local newspapers. The designated places where the document can be reviewed are listed in the advertisements. Normally, copies are not sent to individuals, but your company has been added to the distribution list and will receive a copy of the final document. Because you did not see the notification about the availability of the document for public comment, ATSDR agreed to respond to your comments. A 30-day comment period is usually adequate time for community response. Under some conditions, longer comment periods are provided; shorter comment periods are not usually acceptable.

Comment:
The language of the Federal law that defines the mission of ATSDR requires that the health assessment address only existing pathways of human exposure, not past pathways which may or may not have been present and for which no data is [sic] available.

Response:
ATSDR is an agency within the U.S. Public Health Service and is charged with protection of public health from releases of toxic substances into the environment. As part of that legal and moral obligation to the public, ATSDR is mandated, among other health activities, to conduct public health assessments at hazardous waste sites on or proposed for inclusion on the NPL. The goal of the public health assessment is to determine who has been, is, or may be exposed in the future to hazardous substances present in the environment. Then recommendations are made in the public health assessment as to what follow-up health activities can benefit the exposed population. If we limited our health actions to current or future exposures only, we would be seriously remiss in our obligation to help those who have been exposed to contaminants in the past. Our legal interpretation of the law does not prevent us from assisting those people.

Comment:
Several times in the report the statement is made that human exposure to VOCs may be presently occurring through the use of private well water. The groundwater quality data does [sic] not support this statement. ...all contaminated private well water is known and protected (carbon filters) and a regular sampling program in effect will detect any newly contaminated wells (although experience has shown that there are no new patterns of contamination).

Response: The sampling program cannot guarantee that residents will never be exposed to VOCs in groundwater. Residents have expressed concern that sampling of finished water is not frequent enough, especially during the last month or two before filters are replaced. Therefore, the potential for exposure is certainly there if contaminant levels have increased and the effectiveness of the filter has decreased. In addition, groundwater flow patterns may change with the addition of more and deeper domestic wells such that previously uncontaminated wells may become contaminated without the owner's knowledge. Residents may also be exposed to VOCs from sources other than Chemclene, and for which Chemclene has no obligation to furnish treatment.

Comment: The report contains several errors in the background section regarding current site activities, drums, underground tanks, etc.

Response: We have made the changes suggested by the site owner. We contacted PADER and EPA in an effort to confirm some statements regarding drum disposal and the contents of above ground tanks. There is still considerable uncertainty about site conditions because most of the information about site history comes from the owner's recollection and not from written records.

Comment:
The report infers that the Great Valley Well creates a cone of influence that effects [sic] private water wells in Hillbrook Circle. There are no scientific data to substantiate this.

Response: The report states that the Great Valley Well creates a cone of depression (which it does) and, therefore, influences groundwater flow (also true). This pumping may impact some wells in the subdivision (interviews with well owners). The most recent (March, 1993) of the two hydrogeological tests performed by the Philadelphia Suburban Water Company (PSWC) used a limited number of wells (nine) as observation points. While none of the selected wells were measurably influenced by shutting down the Great Valley Well, there are insufficient data to completely rule out the possibility of an effect on other wells. PADOH does not have a copy of the hydrogeological study conducted in 1979. There are over forty wells in and near Hillbrook Circle, and the groundwater flow is strongly controlled by complex bedrock fractures. Regardless of past conditions, however, the Great Valley Well will likely have even less impact on groundwater reserves in the future because the well is pumping at a lower rate. A far more significant contributor to aquifer dewatering is the continuous pumping from nearby quarries. The report has been altered only to include recent droughts as a factor in the steady decline of the water table over the past decade.

Comment:
Carbon filters are replaced once yearly, and "studies" have shown that this maintenance is adequate to prevent breakthrough.

Response: The report has been changed to state that filters are changed yearly. However, some residents complain that finished water is not tested frequently enough to assure them that the filter system is removing the contaminants of concern.

Comment:
The details of how death records are verified is irrelevant for the stated purpose of this report. ...use of such a data base for all of East Whiteland Township to make implications about one small area of the Township is not scientifically justified and is therefore irrelevant.

Response:
Part of the format of public health assessments is to indicate what types of health data bases are available for review. In the Health Outcome Data Evaluation section of public health assessments, the relevancy and limitations of those data bases are discussed. Yes, care should be taken when determining what implications can be inferred when the study population (an entire town) is much greater than the exposed population (a subset of the town). All that can be seen is perhaps a trend that may warrant further investigation. Indeed, that is one goal of the public health assessment: To identify unusual health trends and to identify any possible health study that may be warranted to further evaluate that trend.

Comment:
There are two areas where wells are "nested" in order to give information on the vertical distribution of contaminants.

Response:
Two well nests of only two wells, each separated by a distance of ¼ mile do not constitute an adequate array of monitoring wells to determine the extent of vertical migration of contaminants. The report has been changed to clarify the need for more well nests.

Table of Contents

Comment:	Why were some drums allowed to stay on site after partial cleanup of soils?
Response:	This report has been corrected to indicate that all drums originally inside the FDA were removed. Some drums that contain unknown materials from other areas of the site are still on site. Sometimes PADER or EPA will allow drums that contain material left from well drilling or soil boring operations to be "staged," or kept, on the site until appropriate removals can take place. Sometimes drums that contain non-hazardous materials are allowed to remain on site. EPA or PADER will have to tell you exactly what material is in the drums and why some drums were allowed to remain after partial cleanup of the soils.
Comment:	Is Chemclene still a solvent recycler as the reports states?
Response:	According to PADER, Chemclene now recycles only non-hazardous chemicals. However, some solvents are still stored on site and, apparently, the sale of solvents continues. The report has been changed to clarify this point.
Comment:	The writer claims to have furnished information to a member of the health assessment team regarding filter maintenance on residential wells. The report states that details of such maintenance are unknown to PADOH.
Response:	Descriptions of filter maintenance and water sampling frequency vary from person to person in the community. The information provided to Mr. Schmeer of PADOH was given during a public availability meeting for the Foote Mineral site, after the Chemclene report was first drafted. The report has been changed to indicate that filters are replaced approximately yearly.
Comment:	The writer is interested in seeing a year by year groundwater quality comparison based upon sampling results.
Response:	The information desired is not available on a yearly basis (see Page 11 of the report). PADOH has recommended that such sampling be conducted.
Comment:	When were the maximum concentrations of TCE and TCA detected? Does the writer correctly understand that PCE appeared in a well 2,500 feet southwest of the site?
Response:	The maximum level of TCE occurred in 1983 and the maximum level for TCA occurred in 1982 in the same well. The report has been changed to include the dates. Also, you are correct in noting that PCE has been found in a well 2,500 feet southwest of the site.
Comment:	Could the State Health Data Center possibly just take the list of 31 cancer deaths due to "other and unspecified types of cancer" which has the statistically significant SMR of 1.632 and at least determine what those "other" causes were?
Response:	The 31 cancer deaths due to "other and unspecified types of cancer" can be obtained from the computer files for the eleven year period 1980-1990. This would be of considerable computer cost and staff time expense. Eleven separate data files would have to be accessed after a formal request with justification of why such information was required. The Health Assessment team does not feel this would be fruitful. The 1990 Pennsylvania Vital Statistics Report (see attached data) indicates there were 3,145 deaths in Pennsylvania in the category "Malignant neoplasm of other and unspecified sites," International Classification of Disease (ICD) code 190-199. The state numeric breakdown by cancer site was as follows:

ICD Code	number of deaths
190 eye	9
191 brain	642
192 other and unspecified parts of nervous system	11
193 thyroid gland	65
194 other endocrine glands and related structures	26
195-199 other underspecified sites	2,392
TOTAL 190-199	3,145

Comment:	We were unaware that the public health assessment was available for public comment until it was too late to respond. This occurred despite a request to receive a copy of the document. Also a 30-day comment period is not enough time.
Response:	The availability of the document for public comment was announced through normal channels, which includes advertisements in local newspapers. The designated places where the document can be reviewed are listed in the advertisements. Normally, copies are not sent to individuals, but your company has been added to the distribution list and will receive a copy of the final document. Because you did not see the notification about the availability of the document for public comment, ATSDR agreed to respond to your comments. A 30-day comment period is usually adequate time for community response. Under some conditions, longer comment periods are provided; shorter comment periods are not usually acceptable.
Comment:	The language of the Federal law that defines the mission of ATSDR requires that the health assessment address only existing pathways of human exposure, not past pathways which may or may not have been present and for which no data is [sic] available.
Response:	ATSDR is an agency within the U.S. Public Health Service and is charged with protection of public health from releases of toxic substances into the environment. As part of that legal and moral obligation to the public, ATSDR is mandated, among other health activities, to conduct public health assessments at hazardous waste sites on or proposed for inclusion on the NPL. The goal of the public health assessment is to determine who has been, is, or may be exposed in the future to hazardous substances present in the environment. Then recommendations are made in the public health assessment as to what follow-up health activities can benefit the exposed population. If we limited our health actions to current or future exposures only, we would be seriously remiss in our obligation to help those who have been exposed to contaminants in the past. Our legal interpretation of the law does not prevent us from assisting those people.
Comment:	Several times in the report the statement is made that human exposure to VOCs may be presently occurring through the use of private well water. The groundwater quality data does [sic] not support this statement. ...all contaminated private well water is known and protected (carbon filters) and a regular sampling program in effect will detect any newly contaminated wells (although experience has shown that there are no new patterns of contamination).
Response:	The sampling program cannot guarantee that residents will never be exposed to VOCs in groundwater. Residents have expressed concern that sampling of finished water is not frequent enough, especially during the last month or two before filters are replaced. Therefore, the potential for exposure is certainly there if contaminant levels have increased and the effectiveness of the filter has decreased. In addition, groundwater flow patterns may change with the addition of more and deeper domestic wells such that previously uncontaminated wells may become contaminated without the owner's knowledge. Residents may also be exposed to VOCs from sources other than Chemclene, and for which Chemclene has no obligation to furnish treatment.
Comment:	The report contains several errors in the background section regarding current site activities, drums, underground tanks, etc.
Response:	We have made the changes suggested by the site owner. We contacted PADER and EPA in an effort to confirm some statements regarding drum disposal and the contents of above ground tanks. There is still considerable uncertainty about site conditions because most of the information about site history comes from the owner's recollection and not from written records.
Comment:	The report infers that the Great Valley Well creates a cone of influence that effects [sic] private water wells in Hillbrook Circle. There are no scientific data to substantiate this.
Response:	The report states that the Great Valley Well creates a cone of depression (which it does) and, therefore, influences groundwater flow (also true). This pumping may impact some wells in the subdivision (interviews with well owners). The most recent (March, 1993) of the two hydrogeological tests performed by the Philadelphia Suburban Water Company (PSWC) used a limited number of wells (nine) as observation points. While none of the selected wells were measurably influenced by shutting down the Great Valley Well, there are insufficient data to completely rule out the possibility of an effect on other wells. PADOH does not have a copy of the hydrogeological study conducted in 1979. There are over forty wells in and near Hillbrook Circle, and the groundwater flow is strongly controlled by complex bedrock fractures. Regardless of past conditions, however, the Great Valley Well will likely have even less impact on groundwater reserves in the future because the well is pumping at a lower rate. A far more significant contributor to aquifer dewatering is the continuous pumping from nearby quarries. The report has been altered only to include recent droughts as a factor in the steady decline of the water table over the past decade.
Comment:	Carbon filters are replaced once yearly, and "studies" have shown that this maintenance is adequate to prevent breakthrough.
Response:	The report has been changed to state that filters are changed yearly. However, some residents complain that finished water is not tested frequently enough to assure them that the filter system is removing the contaminants of concern.
Comment:	The details of how death records are verified is irrelevant for the stated purpose of this report. ...use of such a data base for all of East Whiteland Township to make implications about one small area of the Township is not scientifically justified and is therefore irrelevant.
Response:	Part of the format of public health assessments is to indicate what types of health data bases are available for review. In the Health Outcome Data Evaluation section of public health assessments, the relevancy and limitations of those data bases are discussed. Yes, care should be taken when determining what implications can be inferred when the study population (an entire town) is much greater than the exposed population (a subset of the town). All that can be seen is perhaps a trend that may warrant further investigation. Indeed, that is one goal of the public health assessment: To identify unusual health trends and to identify any possible health study that may be warranted to further evaluate that trend.
Comment:	There are two areas where wells are "nested" in order to give information on the vertical distribution of contaminants.
Response:	Two well nests of only two wells, each separated by a distance of ¼ mile do not constitute an adequate array of monitoring wells to determine the extent of vertical migration of contaminants. The report has been changed to clarify the need for more well nests.