Skip directly to search Skip directly to A to Z list Skip directly to site content

PETITIONED PUBLIC HEALTH ASSESSMENT

AMOCO OIL COMPANY
(a/k/a AMOCO OIL COMPANY - SUGAR CREEK (FINDS) SS#0716)
SUGAR CREEK, JACKSON COUNTY, MISSOURI


APPENDIX J: PUBLIC COMMENTS

ATSDR released the Amoco Oil Company public health assessment for public review and comment from May 7, 1999, through June 20, 1999. Each comment received was logged and became part of the administrative record. This appendix contains both the comments received during the public comment period and ATSDR's response to those comments. The comments have been numbered with the response directly below each comment.

Comment 1: In the initial public health assessment, ATSDR relied heavily on Amoco's RCRA Facility Investigation report (RFI). EPA relied on Amoco's 1995 RFI and 1997 Additional Investigation materials in implementing ATSDR's recommendation to sample indoor air in the Norledge area for chronic levels of benzene. Neither document presents an accurate picture of the soil and groundwater contamination conditions in the neighborhood, or the Amoco source areas immediately up gradient from the private residences.
Response 1: In preparing public health assessments, ATSDR gathers available environmental data from the Environmental Protection Agency (EPA), other government agencies, businesses, and the public. ATSDR did not rely heavily on the 1995 RFI. The only environmental data used from the 1995 RFI in ATSDR' evaluation were for the soil gas medium. Other environmental data sources for this document included Amoco's May 1997 Additional Investigation report; Hydro-LOGIC, Inc.'s, 1998 Limited Subsurface Investigation Results report; ThermoRetec Consulting Corporation's 1998 Basement Air Sampling report; and Amoco's 1998 Sampling Protocol and Sampling Results for the Sewer Excavation. Additional data supplied during the public comment period has been also been incorporated (see Comments 2 through 13 and Comment 67). ATSDR's conclusions and recommendations are based on these available data.
Comment 2: We respectfully request that the ATSDR consider the reference document, Affidavit of Mohammed Aboudah, P.E., June 26, 1996, in making the determinations to be included in the final public health assessment. (Document provided by commentor.)
Response 2:

ATSDR thanks the commentor for providing additional groundwater data for the Norledge area. A short description of the sampling event was added to Section 4.1. A variety of VOCs and SVOCs were added to Table 2, Appendix B. Some of these contaminants exceeded health-based comparison values; however, as discussed in Section 5.2 of this public health assessment, where there is no exposure, there can be no exposure-related adverse health effects. Therefore, because there is no exposure to Norledge area groundwater, there are no changes to the conclusions of the final public health assessment.

Of note, the commentor mentioned that the laboratory which analyzed the groundwater samples was decertified in 1996. ATSDR has chosen to include the data in this report because 1) quality control/quality assurance procedures appeared to be followed and 2) split samples collected and analyzed at a different laboratory yielded contaminant concentrations in the same ranges (see Comment and Response 3).

Comment 3: We respectfully request that the ATSDR consider the reference document, Analytical Summary for Split Sampling Results, August 30, 1996, in making the determinations to be included in the final public health assessment. (Document provided by commentor.)
Response 3: ATSDR thanks the commentor for providing additional groundwater data for the Norledge area. A short description of the sampling event was added to Section 4.1 and the additional data are contained in Table 2, Appendix B. The groundwater data in this report are the split samples mentioned in the previous comment (see Comment and Response 2).
Comment 4: We respectfully request that the ATSDR consider November 1998 air sampling data collected by Compass Environmental and analyzed by Pace Analytical from two homes in the Norledge area in making the determinations to be included in the final public health assessment. (Document provided by commentor.)
Response 4: ATSDR thanks the commentor for providing additional air data for the Norledge area. A short description of the sampling event was added to Section 4.4 and the additional data are contained in Table 7, Appendix B. Overall, the contaminants detected in air during this sampling event were either within the same ranges as the air data previously provided in the public comment version of this document and/or below health-based comparison values. Therefore, there are no changes to the conclusions of the final public health assessment.
Comment 5: We respectfully request that the ATSDR consider November 1998 air sampling data collected by Remediation Technologies, Inc., and analyzed by Pace Analytical from two homes in the Norledge area in making the determinations to be included in the final public health assessment. (Document provided by commentor.)
Response 5: ATSDR thanks the commentor for providing additional air data for the Norledge area. A short description of the sampling event was added to Section 4.4 and the additional data are contained in Table 7, Appendix B. Overall, the contaminants detected in air were either within the same ranges as the air data previously provided in the public comment version of this document and/or below health-based comparison values. Therefore, there are no changes to the conclusions of the final public health assessment.
Comment 6: We respectfully request that the ATSDR consider Hydro-LOGIC's December 1998 Addendum to the Limited Subsurface Investigation report in making the determinations to be included in the final public health assessment. (Document provided by commentor.)
Response 6:

ATSDR thanks the commentor for providing additional environmental data for the Norledge area. Additional groundwater and subsurface soil sampling results were included in the Addendum Limited Subsurface Investigation report. A short description of the groundwater sampling event was added to Section 4.1 and the contaminant data were included in Table 2, Appendix B. Two contaminants, toluene and xylene, detected during this December 1998 sampling event had maximum values that were above the maximum values reported in the public comment version of this document. However, there are no changes to the conclusions of this final public health assessment because residents are not exposed to Norledge area groundwater. Where there is no exposure, there can be no adverse health effects, regardless of the level of environmental contamination.

A short description of the soil sampling event was added to Section 4.2 and the contaminant data were included in Table 4, Appendix B. All contaminants were detected below the maximum values reported in the public comment version of this document. Therefore, there are no changes to the conclusions of the final public health assessment.

Comment 7: We respectfully request that the ATSDR consider December 1998 Norledge area groundwater sampling data collected by Compass Environmental and analyzed by Pace Analytical in making the determinations to be included in the final public health assessment. (Document provided by commentor.)
Response 7: ATSDR thanks the commentor for providing additional groundwater data for the Norledge area. A short description of the sampling event was added to Section 4.1. One contaminant, methyl tert butyl ether (MTBE), which had not been previously analyzed for in groundwater, was detected during this sampling event. The maximum value of MTBE detected was below health-based comparison values. With the exception of total xylenes, the other contaminants detected in groundwater during this sampling event were in the same ranges as the groundwater data previously provided in the public comment version of this document. There are no changes to the conclusions of this final public health assessment because residents are not exposed to Norledge area groundwater.
Comment 8: We respectfully request that the ATSDR consider December 1998 Norledge area groundwater and soil sampling data collected by ThermoRetec and analyzed by Southwest Laboratory of Oklahoma, Inc., in making the determinations to be included in the final public health assessment. (Document provided by commentor.)
Response 8:

ATSDR thanks the commentor for providing additional groundwater and soil data for the Norledge area. A short description of the groundwater sampling event was added to Section 4.1 and the contaminant data are contained in Table 2, Appendix B. MTBE was detected during this sampling event below health-based comparison values. All other contaminants, with the exception of total xylenes, detected in groundwater during this sampling event were in the same ranges as the groundwater data previously provided in the public comment version of this document. There are no changes to the conclusions of this final public health assessment because residents are not exposed to Norledge area groundwater.

A short description of the soil sampling event was added to Section 4.2 and the contaminant data were included in Table 4, Appendix B. One contaminant, MTBE, which had not been previously analyzed for in soil, was detected during this sampling event. The maximum value of MTBE was below health-based comparison values. All other contaminants were detected below health-based comparison values too. Therefore, there are no changes to the conclusions of the final public health assessment.

Comment 9: We respectfully request that the ATSDR consider a January 22, 1999, Norledge area soil sample in making the determinations to be included in the final public health assessment. (Data sheet provided by commentor.)
Response 9: ATSDR thanks the commentor for providing additional soil data for the Norledge area. Three contaminants (toluene, ethylbenzene, and xylenes) in this subsurface soil sample had maximum values above those reported in the public comment version of this document. However, these maximum values were below health based comparison values. Therefore, there are no changes to the conclusions of the final public health assessment.
Comment 10: We respectfully request that the ATSDR consider March 1999 Norledge area water sampling data collected by Compass Environmental and analyzed by Pace Analytical in making the determinations to be included in the final public health assessment. (Document provided by commentor.)
Response 10: ATSDR thanks the commentor for providing additional groundwater data for the Norledge area. A short description of the sampling event was added to Section 4.1 and the contaminant data are contained in Table 2, Appendix B. Overall, the contaminants detected in groundwater were in the same ranges as the groundwater data previously provided in the public comment version of this document. Therefore, there are no changes to the conclusions of the final public health assessment.
Comment 11: We respectfully request that the ATSDR consider Hydro-LOGIC's April 1999 Limited Subsurface Investigation report in making the determinations to be included in the final public health assessment. (Document provided by commentor.)
Response 11:

ATSDR thanks the commentor for providing additional environmental data for the Norledge area. Additional groundwater and subsurface soil sampling results were included in the Limited Subsurface Investigation report. A short description of the groundwater sampling event was added to Section 4.1 and the contaminant data were included in Table 2, Appendix B. One sample showed MTBE above a health-based comparison value in groundwater. Also, toluene and total xylenes were detected above the maximum values previously provided in the public comment version of this document. However, there are no changes to the conclusions of this final public health assessment because residents are not exposed to Norledge area groundwater. Where there is no exposure, there can be no adverse health effects, regardless of the level of environmental contamination.

A short description of the soil sampling event was added to Section 4.2 and the contaminant data were included in Table 4, Appendix B. All contaminants, with the exception of benzene, were detected below health-based comparison values. Benzene exceeded the cancer risk evaluation guide (CREG) comparison value in one sample. Clarification of the public health implications of potential exposure to subsurface soil is described in Section 5.3. There are no changes to the conclusions of the final public health assessment.

Comment 12: We respectfully request that the ATSDR consider the reference document, Split Sampling Results, May 14, 1999, in making the determinations to be included in the final public health assessment. (Document provided by commentor.)
Response 12:

ATSDR thanks the commentor for providing additional groundwater and soil data for the Norledge area. A short description of the groundwater sampling event was added to Section 4.1 and the contaminant data are contained in Table 2, Appendix B. Contaminants were detected within the ranges reported in the public comment version of this document. There are no changes to the conclusions of this final public health assessment.

A short description of the soil sampling event was added to Section 4.2 and the contaminant data were included in Table 4, Appendix B. Contaminants were detected below health-based comparison values. Therefore, there are no changes to the conclusions of the final public health assessment.

Comment 13: We respectfully request that the ATSDR consider an April 1999 Norledge area groundwater sample collected by Compass Environmental and analyzed by Pace Analytical in making the determinations to be included in the final public health assessment. (Document provided by commentor.)
Response 13: ATSDR thanks the commentor for providing additional groundwater data for the Norledge area. A short description of the groundwater sampling event was added to Section 4.1 and the contaminant data are contained in Table 2, Appendix B. Total xylenes were detected above the maximum value reported in the public comment version of this document. However, there are no changes to the conclusions of this final public health assessment because residents are not exposed to Norledge area groundwater. Where there is no exposure, there can be no adverse health effects, regardless of the level of environmental contamination.
Comment 14: EPA is currently sampling basement air in response to ATSDR's recommendation. The decision whether to conduct additional testing will rest on the benzene levels found during the June 1999, testing. Testing for all constituents of BTEX should be performed and factored into any decision making.
Response 14: EPA conducted sampling during June and July 1999 for volatile organic compounds (VOCs) which included BTEX (benzene, toluene, ethyl benzene, and xylene). ATSDR released a public health assessment addendum in March 2000 which provided an evaluation of the June and July 1999 air sampling data as well as air sampling data collected in October 1999.
Comment 15: The EPA basement air sampling regime should be implemented across all seasons of the year. Dr. Brenner indicates in his report titled, BTEX Dose Model Report, June 24, 1996, that "[t]he U.S. EPA recommends an annual/seasonal sampling cycle. If this cannot be accomplished, then two sampling periods should be used which would represent the extremes of temporal concentrations." (BTEX Dose Model Report provided by commentor.) Dr. Brenner directs the reader to review U.S. EPA 540/1-89/002 Risk Assessment Guidance for Superfund Vol.I: Human Health Evaluation Manual (Part A) PB90-155581; 1989.
Response 15: The public comment version of this public health assessment evaluated air sampling data available to the agency at that time. The air data were collected in June, a warm month. Additional air data provided to the agency during the public comment period were collected in November, a cold month. Recent air data collected in June, July, and October 1999 were evaluated in a public health assessment addendum. Overall, ATSDR has evaluated data from both warm and cold months. The range of concentrations within the homes appears consistent.
Comment 16: Dr. Brenner emphasizes the need for annual/seasonal sampling cycles when he points out in his 1996 BTEX Dose Model Report that "[t]he soil gas study for the (Amoco) RFI failed to sample during different seasons, over a long enough period of time to ascertain the long term soil gas values."
Response 16: The soil gas sampling data provided in this document were collected in March 1995. Soil gas samples were not collected in a warm month. The specific levels of contaminants in soil gas might fluctuate during different seasons. However, for ATSDR's purposes, the March 1995 sampling data are considered sufficient because soil gas measurements are used by ATSDR only to help identify the contaminants that would be important to evaluate in air, and not used for exposure purposes.
Comment 17: Dr. Brenner in his 1996 BTEX Dose Model Report made the following statement: "Given the long operational history of the refinery and it's long record of releases of petroleum hydrocarbons, it is likely that the soil gas and indoor air BTEX concentrations were higher in previous years."
Response 17: No air or soil gas data are available from when the facility was operating; therefore, it is unknown what the levels of BTEX were in the past. One of the main purposes of this public health assessment, as stated in Section 2, is a review of data from the off-site Norledge area to determine if current exposures are of potential health concern for local residents. ATSDR's evaluation did not focus on evaluating potential past exposures because chemical-specific air data were not available for the agency to evaluate. However, ATSDR was informed in October 2000 that there may be some limited groundwater data from the 1960s and 1970s. The agency is currently evaluating the possibility of using this groundwater data to model past indoor air concentrations (see Section 6).
Comment 18: Dr. Brenner in his 1996 BTEX Dose Model Report made the following statement: "In addition, it appears that no sampling has been done to establish BTEX background values."
Response 18: At the time Dr. Brenner made this statement in 1996, no efforts had been made to establish background BTEX air levels in the Norledge area. However, typical background air levels for these compounds have been established for rural and industrial areas across the country. Benzene is specifically discussed in this public health assessment (see Appendix E). Also, since Dr. Brenner made his statement in 1996, various indoor and outdoor air sampling events have occurred characterizing the current BTEX air levels in the Norledge area.
Comment 19: Dr. Brenner in his 1996 BTEX Dose Model Report made the following statement: "It is likely that anyone living in the area surrounding the former Amoco Sugar Creek Refinery received absorbed doses of the various BTEXs, via intrusion of BTEX soil gas, from just above background, to an order of magnitude or greater than background. Based on soil analyses, people also likely would have been exposed to other chemicals not modeled."
Response 19: No air or soil gas data are available from when the facility was operating; therefore, it is unknown what the types of chemicals and levels of contaminants were in the past (see Response 17).
Comment 20: Dr. Brenner in his 1996 BTEX Dose Model Report made the following statement: "If someone resided in the area during the period of time when the refinery operated, they would likely have also received additional doses due to air emissions from the refinery due to operational emissions and losses, as well as contaminated surface water."
Response 20: One of the main purposes of this public health assessment, as stated in Section 2, is a review of data from the off-site Norledge area to determine if current exposures are of potential health concern for local residents. ATSDR's evaluation did not focus on evaluating potential past exposures (see Response 17).
Comment 21: ATSDR's public health assessment evaluation focused on off-site air and soil gas. ATSDR should consider the soil gas sampling conducted for and contained in the 1995 Revised RFI report in those areas on-site, but up gradient from the neighborhoods. ATSDR should recommend that EPA require additional soil gas testing on-site, specifically in those areas where groundwater migrates from Amoco to the surrounding neighborhoods.
Response 21: For ATSDR's purposes, the off-site March 1995 soil gas sampling data are considered sufficient because soil gas measurements are used by ATSDR only to help identify the contaminants that would be important to evaluate in air, and not used for exposure purposes (see Response 16).
Comment 22: A groundwater sample collected by Amoco from monitoring well 62R in January, 1999, showed no detection for benzene. Weeks prior to that sample, Hydro-LOGIC collected and analyzed a perched groundwater sample approximately 45 feet from well 62R. This sample showed benzene in groundwater at concentrations of 1,720 ppb. Since ATSDR's public health assessment focuses on gaseous volatile organic compounds ("VOCs") migrating upward toward the ground surface, ATSDR should discount any groundwater monitoring data from Amoco's monitoring wells, and instead request that EPA order Amoco to perform a through study of soils and groundwater, including perched groundwater, in the residential neighborhoods. (Documents provided by commentor.)
Response 22: Concentrations of contaminants in groundwater will vary due to many factors. For instance, wells located only a few feet apart may have entirely different concentrations of contaminants due to well depth and/or geologic factors. ATSDR will not discount Amoco's sampling based on the documents provided by the commentor. Because quality control/quality assurance procedures were followed, ATSDR considers the data useful. Additionally, a system of wells in the Norledge area monitor groundwater conditions on a quarterly basis. Further, the EPA conducted a study of soils in Norledge area residential neighborhoods (surface soil sampling was conducted after the public comment release of this document in May 1999).
Comment 23:

The final public health assessment should not consider Amoco's flawed basement air sampling conducted in Norledge area homes in 1991 and 1993. (Documents provided by commentor.) A cursory review of the documentation of Amoco's "do it yourself" air sampling shows that:

  • Organic vapor monitors were installed in a Norledge area home on August 1 and 2, 1991, and received by the laboratory four days later.
  • Organic vapor monitors were installed in a different Norledge area home on December 2, 1993, and removed on December 3, 1993. The monitors were shipped four days later by Amoco's Health & Safety Officer to the laboratory and received by the laboratory on December 8, 1993.
  • In both instances, Amoco qualified the safety of the sample analysis results to the property owners in terms of OSHA standards, without informing them that OSHA standards are based on exposures lasting 8 hours per day, 5 days per week.
  • Amoco did not prepare or file with the EPA an air sampling work plan for either of these sampling events. This existing documentation doesn't indicate how the monitors were handled or prepared for shipping.
  • Amoco misreports at Section 8-4 in the Revised RFI Report that Environmental Science Services conducted the sampling at the first home in 1991. Amoco performed the sampling itself. (Document provided by commentor).
Response 23: ATSDR did not consider the sampling data from homes sampled in August 1991 and December 1993 in the May 1999 release of this public health assessment. Benzene was not detected in the August 1991 sampling; however, this sampling event had a detection limit for benzene of 50 ppb. This value is either equal to or above ATSDR's health-based comparison values for benzene (i.e., CREG of 0.03 ppb, IEMEG of 4 ppb, and acute EMEG of 50 ppb). The December 1993 sampling event detected benzene at 6 ppb, which is within the range reported in this public health assessment. The other compounds (toluene, ethyl benzene, and xylenes) were not detected during either sampling event. For clarification of the specific concerns mentioned in this comment, ATSDR refers the commentor to EPA.
Comment 24: Dr. Otto Wong, an expert hired by Amoco, stated in a report dated September 11, 1996, that another Amoco expert, Dr. Laura Green, also estimated air benzene concentrations and calculated estimates of air benzene concentrations ranging from 3 ppb to 9 ppb. Dr. Green's findings for the benefit of Amoco are significant in that the EPA's "Quality Assurance Project Plan for Sampling and Analysis of Benzene at the Former Amoco Oil Refinery Sites" dated January 17, 1999, indicates at page 4 that "(T)he benzene action level for chronic exposure has been established by EPA Region VII in consultation with ATSDR as 7 ppb (22 ug/m3)." Please comment on these chronic levels in the final public health assessment. (Documents provided by commentor.)
Response 24: The fact that EPA has set a site specific action level "in consultation with ATSDR" should not be interpreted to mean that ATSDR has officially designated that action level as being the equivalent of a public health hazard. Such an interpretation would not only be incorrect, it would be inconsistent with all of ATSDR's basic practices and policies. Neither the measured benzene levels in homes of the Norledge area nor any of the other exposure levels specified in this comment (3-9 ppb) would be expected to produce any cancerous or non-cancerous adverse health effects, even under conditions of chronic exposure. (For additional information on benzene, please see Appendix E.)
Comment 25: The initial public health assessment fails to evaluate the presence of heavy metals in the neighborhood soil and groundwater. Heavy metals characteristically found in refinery waste are known to be hazardous. In his deposition, Dr. Teitelbaum comments on the lack of study for toxic metals. (Document provided by commentor.)
Response 25: The public comment version of this public health assessment reviewed available environmental data collected in the Norledge area. Soil and groundwater samples were primarily analyzed for BTEX, not heavy metals. The presence of heavy metals in groundwater would not affect the conclusions of this public health assessment because no one has been identified as drinking the groundwater in the Norledge area; where there is no exposure, there can be no adverse health effects. Surface soil data (0 to 3 inches in depth) were not available for ATSDR to review in the May 1999 release of this public health assessment. However, the EPA has since then conducted surface soil sampling (in February 2000) that included analysis for heavy metals. ATSDR's evaluated this surface soil data and concluded that no adverse health effects would be expected for adults or children from exposure to this soil during activities such as gardening or playing.
Comment 26:

At other refinery sites where ATSDR has conducted risk assessments, particularly at those refinery sites being cleaned up under the Comprehensive Environmental Response, Compensation, and Liability Act ("CERCLA"), 42 U.S.C. 9601, et seq., heavy metals and their probable pathways into neighborhoods are always considered. In some instances, the heavy metals create the primary risk to human health from the refinery:

  • Double Eagle Refinery Co. Site, Oklahoma City, OK
  • Prewitt Abandoned Refinery, Prewitt, NM
  • Sinclair Refinery, Wellsville, NY
  • Old Inger Refinery, Darrow, LA
  • Old Citgo Refinery, Bossier City, LA
  • Arrowhead Refinery Company, Hermanntown MN
  • Fourth Street Abandoned Refinery, Oklahoma City, OK

Please explain how ATSDR can issue a final public health assessment for Sugar Creek with no consideration given to the heavy metals used and spilled at the refinery up gradient from the neighborhoods, creeks, and springs, including but not limited to lead, mercury, arsenic, barium, zinc, cadmium, cyanide, selenium, and chromium.

Response 26: ATSDR focuses its evaluations on completed pathways of exposure. Indoor air exposures were identified as the only current completed exposure pathway in the Norledge area. Heavy metals would not be expected to be currently affecting the indoor air pathway. Groundwater in the Norledge area is considered an eliminated exposure pathway. Surface soil data, which included analysis for heavy metals, have been evaluated in a health consultation and ATSDR concluded that no adverse health effects would be expected for adults or children from exposure to this soil during activities such as gardening or playing (see Response 25). Additionally, limited surface water and sediment data, which included analysis for heavy metals, have been evaluated in a health consultation and ATSDR concluded that the contaminants in these media are not a public health threat to residents in the Norledge neighborhood.
Comment 27: Please explain how any health assessment can be issued without one example data point for heavy metals in the neighborhood soil and groundwater. Please offer a rational for any such incomplete report, including the evidentiary and theoretical basis for it.
Response 27: ATSDR bases its findings on data that are available at the time the evaluation is conducted. If the data are insufficient, ATSDR recommends additional sampling. The presence of heavy metals in groundwater would not affect the conclusions of this public health assessment because no one has been identified as drinking the groundwater in the Norledge area. However, for the May 1999 release of this public health assessment, data for surface soil were found to be insufficient. As stated in the Conclusions Update (Section 8), ATSDR had previously concluded that the Amoco Oil Company site in Sugar Creek, Missouri, posed an "Indeterminate Public Health Hazard." ATSDR recommended sampling surface soil. The EPA has since then conducted surface soil sampling (in February 2000) that included analysis for heavy metals. ATSDR's evaluated this surface soil data and concluded that no adverse health effects would be expected for adults or children from exposure to this soil during activities such as gardening or playing (see Response 25 and 26).
Comment 28: No thorough historical review of Amoco's operation of the Refinery and its impact on the neighborhood has ever been performed by any government agency, including ATSDR. The site's history should be evaluated, considered, and referenced in ATSDR's final report. If the final public health assessment indicates facts other than those presented in the accompanying documentation, please cite the source of the contrary information. (Documents provided by commentor.)
Response 28: The purpose of this public health assessment is to review available environmental data from the Norledge area to determine if current exposures are of potential health concern, not perform a thorough historical review of Amoco operations. Section 3 of this document contains the background information considered relevant for the purpose of this public health assessment. Section 10 discusses past and future ATSDR activities with regard to the Amoco site.
Comment 29: ATSDR should explain in its final public health assessment why this site, with its corporate, environmental, and regulatory history should be investigated, evaluated, and ranked differently than those refinery sites cited in Comment 26.
Response 29: ATSDR conducts site-specific health evaluations based on available data and information. ATSDR focused this public health assessment on the Norledge area of Sugar Creek because off-site groundwater contamination had migrated into the Norledge residential area. ATSDR's public health assessment process for evaluating environmental data at the Amoco site is not different than the process this agency followed at the refinery sites mentioned in Comment 26. Also, ATSDR is not an enforcement agency. We do not investigate, evaluate or rank sites - rather we evaluate public health implications.
Comment 30: As recently as March, 1994, the true status of groundwater use had not been definitively established and there is a history of confusion about the existence and use of groundwater wells. For example, an internal Amoco document indicates that as of March 11, 1994, 236 residents had not been surveyed on the use of personal water wells or groundwater use. (Document provided by commentor.)
Response 30:

The March 11, 1994, document defined the private well survey as encompassing an area within approximately a one-mile radius of the facility (Amoco Oil Company, 1994a). The document stated that 236 of the residents in the Sugar Creek Survey were unable to be reached. Some of these residents were located in the Norledge area. The March 1994 document stated that efforts would be made to contact these remaining residents to determine if anyone had a private well. In an April 1994 follow-up survey, 21 residents were contacted about owning a private well, that is, only those residences located in the Norledge area (Amoco Oil Company, 1994b). All 21 responses were "no" to owning a well. Therefore, no confusion exists with regard to private drinking water wells in the Norledge area. No one is currently using private water wells in the Norledge area for drinking water.

The April 1994 document also stated that the remainder of the residents, located outside the Norledge area, would be contacted as part of the RFI Work Plan Addendum (Amoco Oil Company, 1994b). For more information on current RFI activities, ATSDR refers the commentor to EPA.

Comment 31: As recently as November, 1995, the true status of groundwater use had not been definitively established and there is a history of confusion about the existence and use of groundwater wells. (Documents provided by commentor.)
Response 31: A November 1995 letter stated that Amoco representatives visited a Sugar Creek resident about the status of a private well (TriTechnics Corporation, 1995a). The November letter indicated the well was not in an area impacted by refinery operations. At the time, the family was no longer using the well for drinking water (they had a bottled water system.) It is unclear to ATSDR staff how this letter adds to any confusion about the existence and use of groundwater wells in the Norledge area.
Comment 32: Surveys found at least one residence was using the groundwater for "watering and drinking". (Document provided by commentor.)
Response 32: The commentor provided a piece of paper, not dated or a part of any specific reference document, that showed results of a survey indicating an address that had a well used for "water and drinking". ATSDR staff used a map program to find the location of the well with reference to the Amoco site and the Norledge area. The map program showed an address that is outside the Norledge area and to the east of the Amoco site. As stated previously, no one is currently using private water wells in the Norledge area for drinking water.
Comment 33: These wells referred to in Comments 30, 31, and 32 should be identified in the final public health assessment. Since these wells represent completed pathways, ATSDR should request that EPA, not Amoco, perform an investigation fully characterizing groundwater usage in the contaminated zone.
Response 33: As stated in Responses 30, 31, and 32, no drinking water wells were identified in the Norledge area. Therefore, no completed exposure pathway to groundwater currently exists for Norledge area residents. One private well was identified in the Norledge area that was used only for irrigation purposes in the past (Amoco Oil Company, 1994a). Amoco representatives requested the resident not use this well for any purposes. The City of Independence and the City of Sugar Creek water departments verified for Amoco representatives that all residences in the area of concern (i.e., the Norledge area) were hooked up to city supplied water (Amoco Oil Company, 1994a). This information was provided to EPA by Amoco.
Comment 34: In this public health assessment, ATSDR recommends: "(P)revent potential future exposures to contaminated groundwater, including placement of institutional controls on the installation of wells in areas of known groundwater contamination." ATSDR relied on Amoco's 1995 Revised RFI when stating in the initial public health assessment that no residents in the Norledge area own a well. That statement is simply untrue and should be corrected in the final public health assessment. It is difficult to understand how such a mistake could have occurred considering that ATSDR refers to two of these wells as being sampled in July, 1998.
Response 34: ATSDR did not mean to imply that no private wells exist in the Norledge area, only that no residents currently use private wells for household purposes. Sentences clarifying this issue have been added to the main text of the document.
Comment 35: The final public health assessment should follow the criteria established at other refinery sites and recommend that the groundwater under residences and source areas up gradient from residences be cleaned up to MCLs.
Response 35: As a non-regulatory agency, ATSDR's recommendations are meant to be general statements that serve as a guide for regulatory agencies and/or the potentially responsible party to follow. The contaminant clean-up levels are established by regulatory agencies. In response to this comment, ATSDR has added a general recommendation to section 9 stating: "Continue to remediate contaminated groundwater in the Norledge area".
Comment 36: In this public health assessment, ATSDR states "[t]he site and surrounding area have been provided with municipal drinking water since the 1920's; therefore, past and current exposures to groundwater constitute an eliminated exposure pathway." ATSDR presumes that once water is treated by a municipal waterworks, it is safe.
Response 36: The sentences in question do not presume that once water is treated by a municipal waterworks, it is safe. These sentences do not state either way, whether or not a water supply is safe. These sentences only discuss whether exposure is possible, not what the potential health effects could be (health effects are discussed in the Toxicologic Evaluation, Section 5). What the sentences do state is that because residents were provided with drinking water from an entity other than the groundwater under their homes, they are not exposed to the groundwater under their homes. The groundwater under their homes is an eliminated exposure pathway. To clarify the sentence, it has been changed to, "[t]he site and surrounding area have been provided with municipal drinking water since the 1920's; therefore, past and current exposures to Norledge area groundwater constitute an eliminated exposure pathway." Additionally, the municipal water supply is regulated by the Safe Drinking Water Act and subject to state and federal drinking water standards.
Comment 37: In the 1920's, the Independence Water Supply sued Amoco (then Standard Oil of Indiana) for pollution of the water company's intake pipes. The water company had been ordered by the Public Service Commission to find another source of safe water. Water company experts and employees describe in sworn affidavits the quality of the water polluted by Amoco. (Document provided by commentor.)
Response 37: ATSDR's focus for this public health assessment is the Norledge area of Sugar Creek, not the Independence Water Supply. For more information regarding this concern, ATSDR refers the commentor to the Independence Water Supply.
Comment 38: The presumption of water being safe if from a municipal waterworks is put into perspective by Dr. Teitelbaum, where he states with a reasonable degree of medical certainty that water ingestion was a route of exposure for Sugar Creek residents. (Document provided by commentor.)
Response 38: Dr. Teitelbaum's statement is based on potential past intermittent exposures from drinking municipal water collected from the Missouri river. No environmental or medical data from the past are available to validate or refute his statement. With regard to the safety of municipal water, refer to Responses 36 and 37.
Comment 39: No thorough study has ever been required of Amoco to determine if the 8 - 35 million gallon hazardous waste spill under the lower refinery area is migrating down stream toward the Independence Water wells which today supply drinking water to over 200,000 users. No trenching has ever been conducted or required to bedrock east of the RCRA lagoons to determine whether preferential pathways carry the subterranean waste down stream toward the water wells. Jacobs Engineering, in a study performed under contract with EPA, determined that benzene and other pollutants were, in fact, dissolving into the Missouri River alluvium and, thence, to the Missouri River from the site.
Response 39: As stated previously, one of the main purposes of this public health assessment is a review of data from the off-site Norledge area to determine if current exposures are of potential health concern for local residents. This comment is outside the purview of the public health assessment. ATSDR directs the commentor to EPA for further information about the ramifications of the Jacobs Engineering study.
Comment 40: ATSDR should change its determination that water ingestion is an eliminated past exposure pathway. The public health assessment fails to include any discussion or review of documents from the waterworks supplying Sugar Creek and Independence. Until sufficient investigation and study have been performed by qualified specialists of the lower refinery contamination and its proximity to the water supply intake, ATSDR should change its determination that no current exposure pathway exists.
Response 40: ATSDR specifically made the statement that groundwater ingestion is an eliminated pathway with regard to Norledge area residents drinking the contaminated water beneath their homes (see Responses 36 and 37).
Comment 41: ATSDR should explain why at the other refinery sites described in Comment 26, the regulators were concerned over any drinking water intake within a three mile radius of the facility, but no such urgency appears to be present at this site. None of the other refinery sites mentioned herein had 25% of the human water users than are present in Eastern Jackson County.
Response 41: As stated previously, this public health assessment focused specifically on the Norledge area. Further, ATSDR is a non-regulatory agency. To determine why regulators are concerned about a three mile radius at those sites mentioned in Comment 26, the commentor should contact the regulatory agency involved. Typically, ATSDR evaluations consider a one mile radius surrounding sites.
Comment 42: ATSDR should investigate all local governmental entities and public health agencies as sources for historical complaints and health investigations.
Response 42: ATSDR collected community health concerns from local residents in July 1998 and continues to on a regular basis. ATSDR is providing technical assistance to MDOH in it's current cancer health investigation. ATSDR is working with the City of Independence Health Department, the Jackson County Health Department, the Regional and National Multiple Sclerosis Society, the American Cancer Foundation, city and county elected officials, MDNR, and EPA. ATSDR has talked with EPA and ATSDR staff in Region VIII about activities at another Amoco refinery. ATSDR Region VII staff have met with Amoco medical and epidemiological staff to discuss workers' health issues and cohort studies and with the University of Alabama staff investigating the brain cancer cluster at the Napierville Research Center. As other entities are identified, ATSDR will include them in our evaluations.
Comment 43: It is well known in Sugar Creek and Independence that "fill" dirt could be obtained from Amoco's refinery upon request for use on residential property to fill gullies, depressions, or whatever other purposes the homeowner required. Depending on the nature, composition, and refinery source of the "fill" dirt, localized pockets of Refinery generated contamination which may be impacting human health currently exist outside and away from the Norledge plume area. Amoco should be required to disclose to the EPA and ATSDR all off-refinery areas where it has deposited soil, "fill" dirt or other debris generated by or from the Refinery.
Response 43: This public health assessment focuses specifically on the Norledge area of Sugar Creek; therefore, evaluating potential refinery generated contamination outside and away from the Norledge area is outside the scope of this document. With regard to the Norledge area, ATSDR has reviewed both surface and subsurface soil and determined no adverse health effects are likely to occur under current exposure conditions. However, if homeowners are concerned about fill material from Amoco, they should have the fill material in their yards sampled and analyzed. ATSDR would be available to evaluate the data for public health significance.
Comment 44: To further broaden the area potentially impacted by Amoco past and current operations, pipelines which transported crude oil and finished products, run through the neighborhoods south of Norledge Street. We have heard anecdotal stories of major leaks from these pipelines. ATSDR should ask that Amoco provide all documents in its possession concerning these leaks. Using that information of specific leaks, Amoco should be required to conduct soil, soil gas, and groundwater sampling along these pipelines. Only a finding of zero BTEX impact would be sufficient to rule out any areas potentially impacted by the pipe runs.
Response 44: Active petroleum pipelines currently exist on the eastern portion of the site and enter the site from off-site along the eastern and northern borders (Amoco, 2000). The pipelines are not near the Norledge area and are therefore outside the purview of this public health assessment.
Comment 45: ATSDR recommends that "precautionary measures" be taken to "prevent worker and resident exposures to free product that may be encountered during drilling, building, and excavating subsurface soil in the Norledge area." In its final public health assessment, ATSDR should clarify the answers to questions from residents of the contaminated neighborhood, i.e., "[w]ho should a property owner call when encountering contaminated media - the EPA, MDNR or Amoco?" "Who will respond?" "What will be the 'safe' level?" "Will the encounter be reported to the EPA or MDNR and what are the consequences of reporting it?" "What happens if a worker/resident is exposed?" "What agency should be contacted then?" Would the ATSDR recommend that each new building permit issued for the Sugar Creek or Independence area near the Refinery be required to have a notice that "precautionary measures" must be on hand before excavation? Finally, what "precautionary measures" would ATSDR consider appropriate?
Response 45: ATSDR is a non-regulatory agency; therefore, our recommendations are not legally enforceable. ATSDR recommendations are specifically designed to be general statements that serve as a guide for regulatory agencies to follow. In this instance, the specific regulatory agency would vary based on the type of subsurface work to be preformed. EPA, MDNR and the City have developed a protocol for responding to these types of occurrences, as well as to odor complaints. If a resident finds oily soils they should contact the local fire department. The fire department will notify the MDNR regional office and EPA, as needed. If a worker or resident is exposed, the exposed individual should see a physician (and the worker should report the exposure to OSHA). All off-site areas should be remediated before site activities end.
Comment 46: It has been reported that experts from ATSDR attended and spoke at a public meeting in Sugar Creek following issuance of the initial public health assessment. At that meeting it was unclear to the attendees whether the environmental specialist who wrote the initial public health assessment understands the difference between an undiluted soil sample and a composite sample. Please address this issue in the final public health assessment if ATSDR relies on, or cites to, the Amoco Burton Street sewer excavation soil sample.
Response 46: ATSDR staff are aware of the various methods in which soil samples are collected, including the staff working on this public health assessment. The sewer soil sample data were included in this document specifically because the community questioned whether the soil would be sent to a landfill. ATSDR provided information relating to this soil sampling event in Section 4.2.
Comment 47: ATSDR uses the term "comparison value" in evaluating potential health risks and defines it in Appendix C as "media-specific...screening values." In addition, ATSDR irregularly refers to State of Missouri criteria (e.g. with regard to cleanup of hydrocarbon contaminated soil). ATSDR should make reference to Missouri criteria in all cases and particularly with respect to groundwater. For example, this is not done with regard to Missouri criteria for TPH due to either GRO or DRO in Tables 2, 3 and 4.
Response 47: ATSDR only referred to Missouri criteria in one instance, in Section 4.2, when describing soil samples taken during a sewer excavation. As stated in Response 46, Missouri criteria were mentioned in this instance only because the community questioned if soil from the sewer excavation would be sent to a landfill. The decision of whether to send the soil to a landfill depended upon the soil contaminant values in comparison to regulatory values determined by the state of Missouri.
Comment 48: It has also been reported that Dr. Frank Schnell expressed his opinion at the public meeting that benzene is not hazardous to humans in soil until the benzene concentrations reach 700,000 parts per million in soil. This concentration was confirmed with Dr. Schnell and Dr. Hewitt after the meeting, and again with Dr. Schnell by telephone to his office in Atlanta the day following the meeting. Dr. Schnell, speaking as an expert and as a representative of ATSDR, stated that the 700,000 ppm level is not an official concentration level of the agency. In the telephone conversation, he clarified that his figures referenced an ingestion number for benzene, but this was not made clear at the public meeting. Since many members of the public will have no further exposure to the health issues than attendance at the public meeting, or perusing subsequent news media reports on the meeting, ATSDR should very clearly, and in plain English, present to the public its official position on the 700,000 ppm concentration level.
Response 48:

Some confusion has arisen concerning a 700,000 ppm concentration of benzene in soil which Dr. Frank Schnell, an ATSDR toxicologist, mentioned at the Sugar Creek Public Meeting on June 2, 1999. This concentration does not represent an official "safe" level of benzene in soil. ATSDR does not have a non-cancer comparison value for benzene in soil. Solely for the purpose of putting into perspective a deep subsurface soil concentration of 177 ppm benzene found in subsurface soil in Sugar Creek, Dr. Schnell tried to describe what an ATSDR non-cancer comparison value for benzene in soil might be, if one existed. He derived his hypothetical comparison value from the following considerations.

No adverse effects are known to occur in either animals or humans exposed chronically to 1 mg/kg/day or less of benzene orally. Based on ATSDR's default assumptions regarding soil exposure, soil would have to contain 700,000 ppm benzene in order for a 70-kg adult to receive this No-Observed-Adverse Effect Level (NOAEL) dose of 1 mg benzene/kg body weight/day. But since 700,000 ppm would be equivalent to a NOAEL dose, and ATSDR's comparison values may be as much as 100-1,000 times lower than the NOAELs on which they are based, a non-cancer, comparison value for benzene in soil, if ATSDR had one, might be as low as 700 - 7,000 ppm.

This hypothetical comparison value for benzene in soil is based on non-cancer effects, only. ATSDR does have a cancer risk evaluation guide (CREG) of 20 ppm for benzene in soil. However, the CREG is based on chronic (i.e., lifelong) exposure. It is unlikely that chronic exposure occurred as the soil sample was taken at a depth of 12 - 14 feet below the ground surface.

Comment 49: Please comment on the veracity of Dr. Schnell's calculations, and include instructions on how to create a sample with a 700,000 ppm benzene concentration.
Response 49: See 2nd paragraph of Response 48. With regard as to "how to create a sample with 700,000 ppm benzene," a soil sample containing 700,000 ppm (or 70% by weight) benzene would be "wet" with pure benzene and, because benzene is a volatile organic solvent that evaporates rapidly in air, the concentration of 700,000 ppm benzene could not exist for very long in surface soil (unlike earth 12-14 feet below ground). That is why benzene in air, and not benzene in soil, is of primary concern to ATSDR. Air is the benzene-contaminated medium to which humans are most likely to be exposed at Sugar Creek or anywhere else, especially in amounts that may be of public health significance.
Comment 50: ATSDR has included no findings regarding chronic exposure to contaminants found in the Norledge area. The final public health assessment should include such a discussion. No determination of health threats can be made in the off-site area, without a finding regarding chronic exposure.
Response 50:

ATSDR determined residents are exposed to contaminants in indoor air in their homes. Because limited indoor air data were available for ATSDR to review, ATSDR recommended additional indoor air sampling. ATSDR released a public health assessment addendum on March 29, 2000, that evaluated chronic exposures to indoor air in the Norledge area. As stated in the March 2000 public health assessment addendum, current, chronic exposures to the contaminant levels detected in indoor air in Norledge area homes are not likely to be associated with adverse health effects.

In this public health assessment, ATSDR did make several determinations with regard to public health implications. ATSDR determined that short-term exposures to the contaminant levels detected during the limited air sampling event are not likely to be associated with adverse health effects, that contaminated groundwater in the Norledge area is not a source of drinking water, that no residents are experiencing direct exposures to soil gas, and that potential intermittent exposures to subsurface soils in the Norledge area during drilling, building, and excavating would be unlikely to result in adverse health effects.

Comment 51: The final public health assessment should include the curriculum vitae of each person who works on either the report or any investigation leading up to issuance of the final report.
Response 51: It is not ATSDR policy to include curriculum vitae's of each person who works on a report in the final report. This public health assessment involved the work of a multi-disciplinary site team (an environmental scientist, a toxicologist, a medical doctor, a community involvement specialist, a health educator, an epidemiologist, and a regional representative). This public health assessment received peer reviews from agency staff before release to the public.
Comment 52: We object to the phrase "Indeterminate Public Health Hazard", because it suggests that there is known to be a hazard of some nature. On its face, this phrase is misleading and potentially could arouse unwarranted anxiety. A new phrase, such as "Inconclusive Public Health Hazard" would be more appropriate. If this phrase is a term of art which the agency is not free to alter, we suggest that the agency add clarifying test to the fact sheet, summary, and report to make this fact clear.
Response 52: The phrase "Indeterminate Public Health Hazard" is a formal conclusion category (see definition in Appendix G -- Glossary of Terms). To assist the reader, the same definition that is provided in the glossary is footnoted on each page it appears in the public health assessment's main text. The fact sheet is considered final; therefore, no changes have been made.
Comment 53: In the report, and in the fact sheet, a number of "concerns" are listed. These "concerns" include multiple sclerosis (MS) and Alzheimer's disease. Because of the format, the casual reader could conclude that increases of these health issues have been demonstrated at Sugar Creek. There is no quantitative evidence of increases in the incidence of these diseases in the Sugar Creek community.
Response 53: In Section 6, Community Health Concerns, ATSDR clearly states that because data regarding these diseases are not routinely collected by public health agencies, ATSDR was not able to state whether the incidence of these diseases is higher than expected in Sugar Creek. ATSDR further clarifies that these diseases have not been linked with any of the identified chemicals of concern in the Norledge area. ATSDR disagrees that the casual reader could conclude from these statements the agency found increases in these diseases.
Comment 54: The etiology of MS and Alzheimer's disease is not clearly defined, and at least with MS, the etiology is probably complex. Even in those cases in other places around the United States where clusters of MS have been identified, the significance and cause of these clusters is unknown. No MS cluster has been identified in the Sugar Creek area.
Response 54: The etiology of MS and Alzheimer's disease are discussed in this public health assessment (see Appendix F, Health Endpoints). ATSDR does not concur with the commentor's statement that "no MS cluster has been identified in the Sugar Creek area". No formal study of MS incidence has been conducted in the Sugar Creek area; therefore, it is not possible to say that no cluster exists. Similarly, without a formal study, it is not possible to say there is an increase in MS either. Currently, ATSDR's Division of Health Studies (DHS) is funding a multiple sclerosis (MS) prevalence study through the Jackson County Health Department to determine if higher rates of MS exist in Sugar Creek and Independence.
Comment 55: Although there is some language qualifying the list of concerns or illnesses, the incorrect inference could be made that some environmental trigger, possibly perceived to be associated with the refinery site, could be causing increases of these illnesses in the investigated area of Sugar Creek.
Response 55: In Section 6 of the public health assessment, ATSDR clearly states that none of the contaminants, at the levels detected in the Norledge area, have been associated with MS, Alzheimer's, or nervous disorders. The community concern regarding cancer endpoints is being followed up by MDOH.
Comment 56: Including a list of concerns in the report could arouse unwarranted concern in this community and elsewhere and is inappropriate.
Response 56: Learning what people in the area know about a site and what concerns they may have about its impact on their health is of particular importance to ATSDR (see the Forward of this document). Responding to community health concerns is a major focus of the public health assessment process.
Comment 57: The list of 'concerns' should be removed from the fact sheet and executive summary, where there is no discussion putting these 'concerns' in their appropriate context (as there is in the report itself).
Response 57: The fact sheet is considered final; therefore, no changes have been made. In Section 1 (Summary), ATSDR states what the petitioner "believes" are the health issues related to the site. ATSDR feels the sentence in question is appropriate and not out of context.
Comment 58: The report uses terminology such as "incidence" and "cluster" which have both popular usage but also specific epidemiological meaning. At this point there is no statistically significant evidence of clustering or of increased incidence (risk) for any health endpoints at Sugar Creek. The epidemiological literature indicates that a substantial number of apparent clusters of illness may be expected due to chance alone. The likelihood of encountering chance clusters increases as more studies are done, more health endpoints examined, and more geographical area included in the studies. The use of epidemiological language should avoid giving the impression that definitive studies exist when they do not.
Response 58: ATSDR has correctly applied the term "incidence" in this report. Incidence refers to the relative frequency (rate) of the occurrence of a disease or diseases in a population. The rate is usually measured over a period of years and compared to a standard population where the expected rate or occurrence of that disease is known. ATSDR clearly states in Section 6 that data regarding most of the health endpoints (i.e., MS, Alzheimer's disease, and nervous disorders) of concern to the community are not routinely collected by public health agencies; therefore, the agency cannot determine if the incidence of these diseases is higher than expected. These statements in Section 6 do not imply definitive studies exist. The term "cluster" is not used in the main text of the document. MDOH is currently conducting studies (i.e., cancer investigations) in the Sugar Creek area.
Comment 59: We understand this inquiry was prompted by a citizen request which focused on Amoco. So that the public can fairly evaluate the current efforts to study the health of the Sugar Creek community, we believe that the text of the original request should be made available (without identifying the author).
Response 59: ATSDR does not typically include the text of petition letters in public health assessments. The concerns of the petitioner and community are summarized in Section 2 (Purpose and Health Issues). Requests for a copy of the original petition letter can be made to: Freedom of Information Act (FOIA) Office, Centers for Disease Control and Prevention, 1600 Clifton Road NE, Atlanta, Georgia, 30333, ATTN: Lynn Armstrong.
Comment 60: We believe that any inquiry regarding public health in the Sugar Creek community should be broader than the former Amoco refinery site. Although the specific request may be limited in its focus and wording by the petitioner, we believe that ATSDR has a responsibility to respond to any petition in the context of complete public health conditions.
Response 60: ATSDR agrees that any studies of the 'Sugar Creek community' in its entirety should be broader than the Amoco site; however, this initial public health assessment focuses on only a small portion of the Sugar Creek community, specifically the Norledge area. ATSDR documents can be very broad in focus like evaluating multiple exposure pathways for an entire site, or very narrow in focus like evaluating one exposure pathway in a defined area. For this public health assessment, the petitioner and local community expressed their concern about the health risks of known groundwater contamination migrating from the Amoco site into the Norledge area. In response, ATSDR evaluated available environmental data from the Norledge area.
Comment 61: While we believe that there is no evidence showing any increased illness or disease, we think it is misleading and unfair to suggest that the only potential source of contamination or exposure is Amoco. In order to properly respond to the citizen's concern, ATSDR should take a broader view. A number of sources and factors could lead to environmental conditions in the area. The study as focused inappropriately assumes that all environmental and health issues are linked to one source.
Response 61: As stated in Response 58, most of the health endpoints of concern to the community have not been studied (e.x., MS, Alzheimer's disease, and nervous disorders) so it is not possible to state whether there are or are not increases in these health endpoints. Based on site-specific exposures, none of the contaminants, at the levels detected in the Norledge area, have been associated with MS, Alzheimer's, or nervous disorders. ATSDR did not inappropriately assume all the health endpoints were linked to the Amoco site. In Appendix F, ATSDR provides the known sources and factors associated with these and other health endpoints. With regard to environmental issues, ATSDR's public health assessment did specifically evaluate environmental data for the Norledge area regardless of the source (see Response 60).
Comment 62: To avoid misguided anxiety and concern in the community, public presentation of results at public meetings or in the news media should be limited to the actual findings regarding available data and their interpretation.
Response 62: ATSDR staff strive to always present the results of site-specific evaluations to the public in a clear and concise manner.
Comment 63: The report notes that the levels of benzene detected in indoor air samples do not pose a short term risk to residents. However the report is silent on chronic risk, potentially causing the reader to become concerned about the long term health effects. We believe that the report should indicate that the levels found in the test homes are consistent with the range of normal variability found in typical households. The report should also note that there is no scientific evidence that the very low levels detected pose any risk, short-term or chronic.
Response 63: The air data available to the agency at the time the May 1999 public health assessment was released for public comment were limited and may not have been representative of chronic exposure levels (see Section 5.1.1). ATSDR did comment on typical indoor air levels of benzene (see Appendix E). In the May 1999 public health assessment, ATSDR recommended additional indoor air sampling. This air sampling was conducted in July and July of 1999. ATSDR released a public health assessment addendum on March 29, 2000, that evaluated chronic exposures to indoor air in the Norledge area. As stated in the March 2000 public health assessment addendum, current, chronic exposures to the contaminant levels detected in indoor air in Norledge area homes are not likely to be associated with adverse health effects.
Comment 64: The report makes repeated references to dichlorobenzene. In order to avoid confusion, we believe it is important to point out dichlorobenzene is not associated with petroleum products.
Response 64: In the public health assessment text, ATSDR stated the common sources of 1,4-dichlorobenzene (see Section 5.1.2).
Comment 65: The report notes that the highest readings of benzene were noted in the "background" homes, i.e., properties not on Amoco's contamination plume. The report correctly points out that these readings are the result of various household conditions. (Cigarette smoke, household chemicals and solvents, lack of adequate ventilation, etc.) However, the report is silent on the presence of these same conditions in the test homes, where readings were lower than the "background" homes.
Response 65: ATSDR refers to the two homes outside of Amoco's groundwater contamination plume as "control" homes, not "background" homes. ATSDR did not consider the readings taking in these two homes to represent background levels for the Sugar Creek area as the data were limited. The sentence in Section 5.1.1 the commentor is referring to has been changed to a more general statement which includes all homes tested: "Endogenous sources (e.g., second-hand tobacco smoke, auto exhaust from attached garages, glues, paints, and other domestic materials containing benzene) may have contributed to the benzene levels detected in these homes."
Comment 66: The report notes that access to the refinery is not restricted, implying that members of the community are being exposed on the property. First, we would note that inadvertent on-site exposures of limited duration pose no health risk. Second, site access is generally restricted by fencing and by site personnel. Virtually all access to the site is controlled.
Response 66: In a background section of the report, ATSDR has included a Physical Hazards section (see Section 3.3). This section discusses only potential physical, not chemical, hazards associated with the Amoco site. ATSDR did not review on-site environmental data, and therefore cannot comment on the health risk of on-site chemical exposures. ATSDR did state that several areas of the site are not restricted. Amoco has recently reviewed the issue of site access, with specific focus on the risk of unlawful entry, and is currently making further improvements to site access control.
Comment 67: Air samples were collected in October 1999. Please consider these results in the final Public Health Assessment for Sugar Creek. (Document provided by commentor.)
Response 67: ATSDR thanks the commentor for providing additional indoor air sampling data for the Norledge area. A short description of the sampling event was added to Section 4.4 and the additional data are contained in Table 7, Appendix B. Overall, the contaminants detected in air were in the same ranges as the air data previously provided in the public comment version of this document. Therefore, there are no changes to the conclusions of the final public health assessment.
Comment 68: Can I use my well (20,000 gallons approximate) for garden watering and a koi pond?
Response 68: The location of this well was not provided to ATSDR; however, the agency recommends that the commentor not use the well if it is located within the established Norledge groundwater contamination area.
Comment 69: Are we safe to live here?
Response 69: At the maximum concentrations detected to date from chemical-specific data, none of the contaminants identified in the Norledge area would be expected to produce adverse health effects, under site-specific conditions of exposure.
Comment 70: What about the 5 brain tumors viewed on 1 porch since 1986, and 2 more if reviewed to 1984?
Response 70: Information on health endpoints should be provided to MDOH for consideration in their health investigation. Based on available environmental and toxicologic data, none of the contaminants detected in the Norledge area are at levels that would be associated with brain tumors, under current site-specific conditions of exposure.
Comment 71: What about the effects of chronic exposure before closure?
Response 71: Chemical-specific sampling data from when the facility was operating are not available; therefore, ATSDR cannot comment on past exposures. ATSDR did evaluate current environmental data to determine the public health implications of current and future potential exposures. ATSDR determined that no adverse health effects are likely under site-specific conditions of exposure (see Response 50).
Comment 72: The conclusion you reported supports Amoco's test results not independent tests showing conflicting results.
Response 72: ATSDR relied on a variety of reports, as well as independent test results submitted to the agency during the public comment period (see Response 1).


Table of Contents

  
 
USA.gov: The U.S. Government's Official Web PortalDepartment of Health and Human Services
Agency for Toxic Substances and Disease Registry, 4770 Buford Hwy NE, Atlanta, GA 30341
Contact CDC: 800-232-4636 / TTY: 888-232-6348

A-Z Index

  1. A
  2. B
  3. C
  4. D
  5. E
  6. F
  7. G
  8. H
  9. I
  10. J
  11. K
  12. L
  13. M
  14. N
  15. O
  16. P
  17. Q
  18. R
  19. S
  20. T
  21. U
  22. V
  23. W
  24. X
  25. Y
  26. Z
  27. #