Technical Document Review: Fruit Valley Neighborhood Indoor Air Evaluation Work Plan
CADET MANUFACTURING COMPANY
VANCOUVER, CLARK COUNTY, WASHINGTON
The Washington State Department of Health (DOH) has prepared this health consultation report to summarize the results of its technical review of the Cadet Manufacturing Company (Cadet), Fruit Valley Neighborhood September 2003 and January 2004 Indoor Air Evaluation Work Plan, dated September 2003. The work plan describes Cadet's follow-up plans for indoor and sub-structural air sampling in the Fruit Valley Neighborhood (FVN) through January 2004, the results of which are intended to be used to complete an evaluation of chlorinated solvents in indoor air.1 DOH conducted its review of the plan because of the potential health risks associated with this site. DOH prepares health consultations under a cooperative agreement with the Agency for Toxic Substances and Disease Registry (ATSDR).
The FVN, located in Vancouver, Washington, is underlain by chlorinated solvent contaminated groundwater that has migrated from the nearby Cadet Manufacturing facility (Cadet). Cadet is located at 2500 West Fourth Plain Boulevard, generally west of the FVN. Groundwater data collected in 2002 indicates that the contaminated groundwater has migrated eastward to the Burlington Northern Santa Fe (BNSF) railroad tracks, northward between West 31st Street and La Frambois Road, and southeastward toward Port of Vancouver property.2 The predominant chlorinated solvents found in groundwater below the FVN include trichlorothylene (TCE) and tetrachloroethylene (PCE). Other chlorinated solvents, including 1, 1 dichloroethene (1,1-DCE), have also been detected.
Chlorinated solvents dissolved in groundwater can evaporate and move up through the soil and enter homes and other buildings affecting indoor air quality. The condition of the foundation (e.g., cracks or holes in concrete lined basements and slab-on-grade, exposed soils in crawlspaces and earthen basements) and operation of heating and ventilation systems are some of the significant factors affecting the movement of the contaminants from groundwater to indoor air.
Indoor air sampling has only been conducted at a small percentage of the FVN homes underlain by the chlorinated solvent contaminated groundwater since January 2002. DOH determined that the solvents levels detected at three basement homes sampled in January and August 2002 exceeded those expected in a residential structure and that the levels posed a long-term health threat.3 Cadet subsequently installed soil vapor vacuum systems at these three homes in September 2003 based on DOH's recommendations that exposures to chlorinated solvents migrating from groundwater to indoor air be eliminated at these homes (Craig Rankine, Washington State Department of Ecology, personal communication, September 16, 2003).3 Cadet, at Ecology's request, also installed soil vapor vacuum systems at three additional homes in the FVN.
DOH was informed by Ecology on September 16, 2003, that Cadet was conducting additional indoor air sampling in the FVN the week of September 22, 2003, (Craig Rankine, Washington State Department of Ecology, personal communication, September 16, 2003). The potential health risks associated with this site compelled DOH to request a copy of the work plan for review. DOH received the work plan on September 29, 2003. DOH was informed on October 3, 2003, that the planned indoor air sampling started on October 2.4
Cadet's Fruit Valley Neighborhood September 2003 and January 2004 Indoor Air Evaluation Work Plan continues to provide measures for evaluating indoor air quality at homes above the chlorinated solvent contaminated groundwater plume emanating from the Cadet property. Overall the plan provides some good steps for conducting a partial indoor air quality evaluation in the southwestern portion of the plume where some of the highest groundwater concentrations have been detected. However, the proposed steps are inadequate for meeting the goal of the plan, which Cadet has indicated is to complete an evaluation of chlorinated solvents in indoor air in the FVN.1Health issues identified by DOH during its review of the plan are summarized below. Recommendations follow each identified issue.
- Section 1.0, Introduction - As noted above, the work plan describes Cadet's follow-up plans for completing an assessment of chlorinated solvents in indoor air in the FVN. However, only a limited number of rounds of indoor air sampling are proposed at a limited number of homes overlying only a portion of the plume of chlorinated solvent contaminated groundwater. The groundwater contaminant plume underlies approximately 200 properties and it is anticipated that elevated levels of chlorinated solvents could remain in shallow groundwater for a number of years. Consequently, the work plan is not adequate for completing an assessment of the effect of contaminated groundwater on indoor air quality in the FVN. DOH understands that Cadet is installing and will be operating an air sparging/soil vapor extraction system on its property to begin remediating groundwater with TCE concentrations greater than 500 micrograms/liter (ug/l) and that Cadet will be conducting a pilot test for a recirculating groundwater remediation well system for the FVN. However, the effectiveness of either system is currently unknown.
Recommendations - A comprehensive work plan, rather than a plan limited to two sampling rounds, should be developed for an on-going evaluation of indoor air quality and possible associated health concerns at homes and businesses in the FVN overlying and immediately adjacent to the chlorinated solvent plume. It should be noted that DOH does not believe that one indoor air sampling round at a home is adequate for determining whether indoor air is, or will be in the future, affected by the chlorinated solvent groundwater plume underlying the FVN.
There are a number of information sources that Cadet and Ecology can consult to assist them in preparing such a comprehensive plan. All of these sources have been brought to Ecology's attention in the past and include:
- The U.S. Environmental Protection Agency (EPA) draft guidance for evaluating the groundwater to indoor air pathway at homes located above or near contaminated groundwater.5 This EPA guidance was available as early as 1999 and it was recently revised and re-released in November 2002. This is a well-publicized document that provides guidance for helping identify homes where groundwater contaminated with volatile organic compounds (VOCs) might pose a risk to indoor air quality.
- Guidance developed by other states for evaluating the groundwater to indoor air pathway.
- State or federal environmental agencies overseeing evaluations of the groundwater to indoor pathway. The long-term monitoring of the groundwater to indoor air pathway being overseen by Mr. Ed Jones, the Ecology project manager for Philip Services Corporation (PSC) - Georgetown facility is a good example of such work.
The two homes sampled in August 2002 with canister pressures near zero are proposed to be re-sampled in September 2003 and January 2004. Seven of the 20 buildings with canister pressures at or near zero or elevated in January 2002 are planned for re-sampling in January 2004, a time of year when elevated levels of chlorinated solvents were detected in indoor air in the past. Four of the twenty homes are proposed for re-sampling in September 2003, a time of year when indoor air levels of chlorinated solvents have been observed to be lower. No samples are planned to be collected from nine of the twenty buildings.
Recommendation - The sampling plan should be expanded to address the homes with questionable sample results.
Recommendation - Future references to the sampling results at the daycare and former school buildings should provide accurate information. Additional indoor air sampling should be conducted at the daycare facility, which contains a basement, has only been sampled once, and overlies the contaminated groundwater plume, to ensure that groundwater is not affecting indoor air.
Recommendation - Detailed information about the building foundations and other building features should be obtained and recorded for each sampled building so it can be determined whether the building is vulnerable to the migration of chlorinated solvents into indoor air.
Recommendation - DOH recommends that Ecology review and determine whether Cadet's vapor intrusion modeling approach is adequate since the groundwater cleanup levels developed using this approach are being used by Cadet to make significant site decisions that could affect the health of the FVN community.
To address some of the uncertainty associated with modeling, DOH recommends Ecology have Cadet conduct concurrent groundwater, soil gas and indoor air sampling to confirm that their predicted groundwater levels are, in fact, protective of indoor air quality at homes above the plume.
The FVN is an area where children could potentially be exposed to chlorinated solvents migrating from contaminated groundwater to indoor air. Children can be uniquely vulnerable to the hazardous effects of environmental contaminants. Children breathe more air per pound of body weight than do adults resulting in higher levels of exposure to contaminants in air. Additionally, the fetus is highly sensitive to many chemicals, particularly with respect to potential impact on childhood development. For these reasons, DOH has determined that it is very important to consider the specific effects that indoor air contaminants may have on children, as well as other sensitive populations and will continue evaluating these potential exposures as data become available.
Indoor air within the portion of the Fruit Valley Neighborhood overlying or immediately adjacent to the chlorinated solvent contaminated groundwater that has migrated from the Cadet Manufacturing site poses an indeterminate health risk. The Fruit Valley Neighborhood September 2003 and January 2004 Indoor Air Evaluation Work Plan requires modification to ensure that a comprehensive plan is in place for evaluating the public health implications associated with the groundwater to indoor air exposure pathway.
- The following recommendations summarize those presented above:
- A comprehensive work plan needs to be developed for on-going evaluation of the groundwater to indoor air pathway in the FVN where levels of chlorinated solvents pose a potential health risk.
- Homes where indoor air sampling canister pressures were at or near zero or significantly elevated during the January 2002 sampling event, as well as any subsequent sampling rounds, should be addressed to ensure that building occupants are not being exposed to harmful levels of chemicals.
- Facts about previous sample results should be accurately described in future plans and reports.
- Detailed information about the building foundation and other building features should be obtained and recorded for each building where indoor air samples will be collected.
- Cadet's vapor intrusion modeling approach should be reviewed by Ecology to determine whether the approach is adequate since the groundwater cleanup levels developed using this approach are being used by Cadet to make significant site decisions that could affect the health of the FVN community. Ecology should ask Cadet to conduct sampling to confirm the modeling results.
A revised indoor air evaluation work plan should be developed to include DOH's recommendations, which are described in detail in the discussion section of this health consultation report.
Washington State Department of Health
Office of Environmental Health Assessments
Site Assessment Section
Wayne Clifford, Manager
Site Assessment Section
Office of Environmental Health Assessments
Washington State Department of Health
ATSDR Technical Project Officer
Division of Health Assessment and Consultation
Agency for Toxic Substances and Disease Registry
- AMEC Earth & Environmental, Inc. Fruit Valley neighborhood September 2003 and January 2004 indoor air evaluation work plan. Portland, Oregon: AMEC Earth & Environmental; 2003 September.
- AMEC Earth & Environmental, Inc. Semi-annual groundwater monitoring report 2002. Portland, Oregon: AMEC Earth & Environmental, Inc.; 2003 February.
- Washington State Department of Health. Indoor air quality evaluation, Cadet Manufacturing Company site. Olympia, Washington: Washington State Department of Health. 2003 May 6.
- Washington State Department of Ecology. E-mail from Craig Rankine to Barbara Trejo, Washington State Department of Health, concerning indoor air sampling schedule. Olympia, WA, October 3, 2003.
- U.S. Environmental Protection Agency. Draft guidance for evaluating the vapor intrusion to indoor air pathway from groundwater and soils (subsurface vapor intrusion guidance). U.S. Environmental Protection Agency. 2002 November.
- Washington State Department of Health. Letter from Barbara Trejo to Craig Rankine, Washington State Department of Ecology, concerning interim action work plan for groundwater source control. Olympia, WA, May 28, 2003.
- Washington State Department of Health. E-mail from Barbara Trejo to Craig Rankine, Washington State Department of Ecology, concerning indoor air evaluation work plan. Olympia, WA, October 16, 2003.
This Health Consultation was prepared by the Washington State Department of Health under a cooperative agreement with the Agency for Toxic Substances and Disease Registry (ATSDR). It is in accordance with approved methodology and procedures existing at the time the health consultation were begun.
Technical Project Officer, SPS, SSAB, DHAC
The Division of Health Assessment and Consultation, ATSDR, has reviewed this public health consultation and concurs with the findings.
Chief, SPS, SSAB, DHAC