2Department of the Air Force, Environmental Restoration Branch, 75th CEG/CEVOR â Bldg. 5,. 7274 Wardleigh Road, Hill Air Force Base, UT 84056-5137.
Keeping up with the Joneses: Residential Data Management Jennifer P. Miller1, Shirley J. Steinmacher1, Kenneth K. Moosman1, Peter A. EerNisse1, and Jarrod D. Case2 1
MWH Americas, 10619 South Jordan Gateway Suite 100, Salt Lake City, UT 84095
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Department of the Air Force, Environmental Restoration Branch, 75th CEG/CEVOR – Bldg. 5, 7274 Wardleigh Road, Hill Air Force Base, UT 84056-5137
ABSTRACT At Hill Air Force Base (AFB), groundwater contaminated with volatile organic compounds (VOCs) consisting primarily of chlorinated solvents has migrated from on-base sources to beneath seven residential communities surrounding the base. Hill AFB developed the Basewide Residential Indoor Air Sampling Program to evaluate the potential soil vapor to indoor air pathway and its impact on the residential communities. Today the program is one of the largest residential sampling programs in the country, with more than 5,000 indoor air samples collected from more than 1,600 residences. With the large number of residences and communities involved, the development of a data management protocol that balances the need to collect and manage large amounts of residential data (i.e., communications, schedules, analytical results, household product inventories, etc.) with consideration for residents’ schedules and concerns is paramount to the success of the project. Daily communication between Hill AFB and their consultants involved in the project is required for timely delivery of accurate data to the community. To accomplish this, two database interfaces were developed for data entry and tracking as well as a chemical product database for tracking of household products (i.e., potential interior sources). Information transfer to Hill AFB is achieved through weekly uploads to a file transfer protocol (FTP) site, e-mail, electronic data deliverables, and periodic reports. The unique structure of the project and design of the database enables near real-time data sharing with Hill AFB, and serves as a model for similar large-scale cooperative projects.
INTRODUCTION As more site investigations move toward the collection of residential indoor air samples for evaluating vapor intrusion, the nature and variety of residential data (communications, schedules, analytical results, household product inventories, etc.) pose a unique challenge with respect to data collection, tracking, storage, and transfer. Because the results can affect the lives and property of residents, this challenge is best addressed early in the development of a program. In doing so, a consistent protocol is followed throughout the duration of a sampling program with accurate and complete data delivered to residents1. Indoor air sampling has been occurring at Hill Air Force Base (AFB) since 1993 in communities surrounding the base as part of remedial investigations, risk-assessments, and site-specific environmental investigations. In 2003, Hill AFB implemented the Basewide Residential Indoor Air Sampling Program to address the issue of vapor intrusion at sites basewide. In response to the challenge of residential data management, Hill AFB’s environmental consultant responsible for collecting and evaluating air sampling data developed a residential “arm” of the consultant’s
existing database to collect and manage residential information. Two database interfaces were also developed to facilitate the entry and transfer of the data to and from Hill AFB and its community relations team. A data management protocol including the database and its interfaces has been in place for over five years, and serves as a model for similar large-scale cooperative projects.
BASEWIDE RESIDENTIAL INDOOR AIR SAMPLING PROGRAM Hill AFB is located in northern Utah, approximately 25 miles north of Salt Lake City and five miles south of Ogden (Figure 1). The base occupies approximately 6,700 acres. Environmental investigations at the base have principally focused on nine Operable Units (OUs), each of which designates an area comprised of contaminated groundwater that has migrated from on-base sources to off-base communities. Extensive Figure 1 – Hill AFB Areas of Investigation remedial investigations in each OU have revealed that the groundwater is contaminated with volatile organic compounds (VOCs), some of which are more prevalent in certain OUs than others. However, the primary VOC contaminant in the majority of the OUs is trichloroethene (TCE). Because of the presence of VOCs in the shallow groundwater at off-base locations, the potential exists for these compounds to volatilize from groundwater, migrate through the soil, and enter homes, potentially exposing occupants to unacceptable contaminant levels in indoor air. In an effort to identify and subsequently mitigate any potential risks to off-base residents by this exposure pathway, Hill AFB established the Basewide Residential Indoor Air Sampling Program in 2003. Approximately 100 mitigation systems, most of which are sub-slab vapor removal systems, have been installed in homes since the beginning of the program.
KEY PERSONNEL The management of residential data for the Hill AFB program involves a cooperative effort between the Hill AFB project manager and Environmental Restoration Branch staff, a community relations firm housed at the base, an environmental consultant, and the laboratory. A summary of the responsibilities of the organizations and teams involved in the program is presented in Figure 2.
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Figure 2 – Key Personnel
Hill AFB Environmental Restoration Branch The Hill AFB Environmental Restoration Branch is responsible for directing the environmental investigation and cleanup programs at the base, including groundwater, soil, and indoor air programs. The purpose of the Environmental Restoration Branch is to identify contamination, evaluate the risks and potential exposure pathways to humans and the environment, and to implement remedial actions. The Environmental Restoration Branch includes a project manager responsible for overseeing and guiding the Basewide Indoor Air Sampling Program. The responsibilities of the project manager are summarized in Figure 2.
Hill AFB Community Relations The Hill AFB community relations team is housed at Hill AFB, and is the primary liaison between the community and Hill AFB for communicating the overall progress of the air sampling program as well as other environmental programs at the base.
Environmental Consultant Hill AFB’s environmental consultant is contracted for the purpose of carrying out the residential data collection effort and evaluating the data. The consultant includes the sampling coordinator, the indoor air sampling team, a database manager, and a team of scientists who evaluate the data to provide technical recommendations to Hill AFB. The consultant communicates with the Hill AFB project manager, the community relations team, and the residents.
Laboratory The laboratory is responsible for providing sample equipment to the sampling team, and analyzing indoor air samples.
SAMPLE COLLECTION Approximately 1,000 samples per year are collected from homes surrounding Hill AFB. Most initial samples are collected in homes during the winter months because studies have indicated that the likelihood and/or level of detections in indoor air are higher in winter1, 2, 3. A typical week of sampling consists of two canister drop-off days (Monday and Wednesday) and two canister pick-up days (Tuesday and Thursday). The sampling coordinator conducts a preliminary interview with the resident over the telephone during scheduling to obtain general information about the occupants and construction of the home. At the time of the sampling appointment, the sampling team enters the residence and conducts a follow-up residential interview, primarily to identify any household products or activities that might interfere with the air sample results. The samplers use a tablet computer and a database interface to record data collected in the field. If any such products are found inside the home, the samplers request that the resident remove the product(s) from the home for the duration of sampling activities. Sampling appointments are occasionally canceled due to the presence of household products in the residence that are known to contain target compounds.
Indoor air samples are collected in stainless steel 6-liter Summa canisters equipped with a 24hour flow-rate controller. All canisters used are batch-certified-clean canisters, dedicated to the Basewide Residential Indoor Air Sampling Program. The samplers place the canister in the lowest livable space in the residence at a height of approximately 3 feet above floor level. The samplers then open the valve to allow air to fill the canister. After approximately 24 hours, the samplers return to the residence to turn off and retrieve the canister. Canisters are closed tightly and shipped to a laboratory, where the samples are analyzed for target VOCs corresponding with those found in the underlying groundwater.
DATABASE STRUCTURE AND INTERFACE Hill AFB ERPIMS and Consultant Database Analytical data collected for the Air Force are delivered to Hill AFB in ERPIMS format. A firewall is present that prohibits direct linkage to a central database by parties involved in the program; therefore data exchanges are typically made through e-mail, a file transfer protocol (FTP) site, or by compact disc (CD). Data collected by the consultant are initially stored in the consultant’s database, which uses Oracle software. The consultant’s database contains information from many sites at Hill AFB, including groundwater, soil, and air analytical data collected during various investigation and long-term monitoring programs. The consultant provides an upload to ERPIMS of all new and updated analytical data on a quarterly basis. As a result, the consultant’s database, while separate from the Hill AFB ERPIMS database, is structured to facilitate this transfer. Residential analytical data and communications information must be shared more frequently than every three months, as final results are promised to residents within approximately two months of the sampling date. As a result, transfer of residential data occurs more frequently. The consultant uses a residential communications interface to track, among other things, sampling appointments, contact information, and communications with residents. A residential sampling inventory interface is used primarily by the sampling coordinator and the sampling team to record home construction, household product, weather, and sampling event information. The air sampling team members enter information directly into a field copy of the database through the use of tablet computers.
Residential Communications Interface The residential communications interface (Figure 3) is run through a Microsoft Access front end. Hill AFB has a similar interface, which is capable of displaying similar information to the Hill AFB staff and the community relations team, which is housed at Hill AFB. The information viewable in the consultant’s residential communications interface includes contact, communications (with residents by both Hill AFB and the consultant), mitigation system, scheduling, and historical results information. Contact information and mitigation system information (with the exception of remarks) cannot be entered or modified by the consultant, as these are managed and owned by Hill AFB. The purpose of the communications interface is not only to facilitate data entry, but also to provide an easily viewable synopsis of the participation of a given residence in the program. 5
Figure 3 – Residential Communications Interface
Contact Information Window Contact information consists of names, addresses, telephone numbers, and e-mail addresses of residents. Information about residents’ preferences with regard to how and when they are contacted is also included. Contact information is entered and updated by only Hill AFB. Communications Windows When any consultant or Hill AFB team member communicates with a resident, a summary of the communications is entered into either the Hill AFB or the consultant database using the respective interfaces. Information entered into their interface by Hill AFB or community relations staff is stored in a table containing Hill AFB communications. Information entered into their interface by consultant team members is stored in a table containing consultant communications. The respective communications tables are shared through weekly transfers, where the consultant receives new and updated information from Hill AFB and Hill AFB receives new and updated information from the consultant.
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Mitigation System Window Mitigation system information consists of installation date, site walk dates, inspection dates, and system characteristics, which are entered by Hill AFB. Similar to contact information, mitigation system information is entered and updated by only Hill AFB; however the window also includes a remarks section, where both Hill AFB and the consultant can enter remarks. Remarks entered by Hill AFB are stored in a table containing Hill AFB-owned remarks; while remarks entered by the consultant are stored in a table containing consultant-owned remarks. Scheduling Window The sampling coordinator schedules the collection of air samples for the entire program, and records the information in the database using the residential communications interface. Scheduling information includes the pick-up and drop-off dates and times of the sampling appointment. It also includes the type of sample (e.g., initial sample [IS], quarterly confirmation sample [QCS], initial performance sample [IPS], etc.); the contract task order under which a sample is collected; remarks; and check boxes to indicate whether the sample was collected and whether the samplers noted an “Action Alert” (notes from the sampling event that may affect the interpretation of results or should result in some action on the part of Hill AFB). Historical Results Window The consultant can view historical results from samples previously collected at a residence in the residential communications interface. Historical results are available for reference to facilitate communication between the viewer and the resident.
Residential Sampling Inventory Interface A residential sampling inventory interface was developed and also runs through a Microsoft Access front end (Figure 4). This interface is primarily used by the sampling coordinator during the preliminary telephone interview and in the field by the sampling team. Resident contact information is viewable on the master form of the interface (shown in Figure 4), and other information is viewable through subforms, which are linked to the master form. The information viewable in the subforms includes home construction information, appliance information, occupant information, a household chemical product inventory, household activity information, and sampling event information. Resident Contact Information Resident contact information viewable in the residential sampling inventory interface is drawn from the same location as the information available in the residential communications interface. The contact information window includes resident name, address, and telephone number primarily for the use of the samplers. Home Construction and Appliance Subforms Home construction and appliance information includes details about the home construction (the presence of a basement, the type of veneer on the home, whether the home has a sump, etc.), the
Figure 4 – Residential Sampling Inventory Interface Master Form
heating, ventilation, and air conditioning systems, as well as other appliances that may affect circulation in the home. The sampling coordinator usually enters this information during the preliminary residential interview; however it is often modified and updated in the field. An example home construction subform is shown in Figure 5. The information in most of the subforms is tabulated, and drop-down menus with standard choices are available for quick data entry. Figure 5 – Home Construction Inventory Subform
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Occupant Information Subform Information about occupants of the home is collected if that information could potentially affect the interpretation of the air sample results. For example, smoke or chemicals brought into the home on clothing can impact indoor air results, so information is collected if any residents in the home smoke or work with solvents. This information is entered into the occupant information subform. Household Chemical Product Subform A household chemical product inventory is conducted during every sampling event. Samplers review chemical products stored in the home (to the extent that the resident is comfortable) and note products containing solvents using the product subform. The household chemical product records for a residence are linked to a household chemical product database that has been developed for the sampling program and is described below. These products, and notable chemical constituents potentially affecting indoor air results, are stored in the database and easily linked to resident records. Household Activity Subform Household activity information includes details and dates of activities that could affect the interpretation of air sample results. For example, if residents recently brought home dry-cleaned clothing, painted, or installed new carpet, this information would be noted in the household activity subform. Sampling Event Subform Details about the sampling event are recorded in the sampling event subform (Figure 6). The details include date and time of canister placement and retrieval, weather observations, canister and pressure gauge identification numbers, and sampling personnel.
Figure 6 – Sampling Event Subform
Household Chemical Products Database A household chemical product database was developed to aid in the household chemical product inventory that the samplers conduct with the placement of each air canister. This database is viewable through the residential sampling inventory interface (Figure 7). The name brands, manufacturer information, product numbers (when available), and applicable chemical constituent information of more than 2,400 household chemicals are stored in the database. While the sampling team is conducting the household chemical inventory, they can match the household products they find in the home, many of which contain the same chemicals they are sampling for, with those in the database, enabling them to make on-site decisions about whether to continue with air sampling if an interior source is suspected. Also, samplers can update the database with new chemicals in the field. Chemical products can be linked to residential records with associated active and inactive dates (approximate dates when the chemical was brought into the home and when the chemical was removed). An example of several products linked to a residence in the products subform is shown in Figure 8.
Figure 7 – Household Chemical Products Database
Figure 8
– Household Chemical Products Linked to Resident Record
DATA TRANSFER The transfer of data between Hill AFB, its community relations team and consultant is illustrated in Figure 9 and described in the paragraphs that follow.
Figure 9 – Data Transfer
Transfer of Data to and from the Indoor Air Sampling Team The sampling team and the database manager exchange data weekly via a file transfer protocol (FTP) site. At the beginning of the week (usually Monday) copies of tables relevant to the residential sampling inventory interface as well as the Microsoft Access front end are available on the FTP site for retrieval by the air sampling team. After sampling occurs, the sampling team uploads the modified field database to the FTP site for retrieval by the database manager (typically on Thursday). Meanwhile, a new copy of the database, including new scheduling information, is waiting on the site for retrieval by the sampling team for the next sampling event. The database manager is responsible for providing new copies of the database to the sampling team and for retrieving updated field copies of the database from the FTP site. Once the updated copy is downloaded from the FTP site, the database manager merges the updated field tables with the primary consultant database. During this process, the database manager performs a quality check on the data and reviews questionable information (updates to old sampling records, conflicting records, etc.) before it is merged with the primary database.
Transfer of Data from the Laboratory Preliminary Analytical Data Preliminary analytical data are provided to the consultant by the laboratory in portable document format (PDF) and as an electronic data deliverable via e-mail within three working days after the sample canister is retrieved. The preliminary data are checked against the sample chains of custody before the data are uploaded to the consultant’s database. The consultant then forwards the preliminary data PDF to Hill AFB and the community relations team via e-mail and uploads the preliminary data into the database for weekly delivery with the communications data. The purpose of providing preliminary data is to enable Hill AFB and the community relations team to notify residents quickly if detections occur. Typically when detections occur, residents
are notified by telephone or are visited in person by the Hill AFB project manager and the community relations team. Final Analytical Data The laboratory provides final electronic analytical data deliverables along with a hard copy report to the consultant typically within 21 working days after the sampling event. A ten percent check of the electronic data is performed against the hard copy report and field chains of custody. Electronic and manual checks searching for result and laboratory quality control outliers are performed on all electronic data before they are uploaded to the consultant’s database.
Weekly Data Sharing Residential communications and scheduling information (viewable in the residential communications interface) are shared weekly between the consultant and Hill AFB by way of an FTP site. Each party creates a transfer database and uploads it to the FTP site. The other party retrieves the appropriate transfer database from the site and merges the data with their existing database. A preliminary electronic analytical data deliverable (when available) is also included in the consultant’s upload. This preliminary electronic data deliverable corresponds with the preliminary analytical data provided by the consultant in PDF format via e-mail.
Final Residential Results Reports Final residential reports are provided to Hill AFB in PDF format typically within four working days of when final results are received from the laboratory (approximately within one month of sample collection). Final reports consist of a summary of final analytical results along with a report containing details about the sampling event and the results of the household chemical products inventory. The final reports are generated by the consultant and reviewed for errors. Once all information on the reports is verified, the reports are provided to Hill AFB on an FTP site. The Hill AFB community relations team retrieves each report, attaches a letter, removes the inventory information, and mails the packet to the residents. Residents typically receive results packets no later than two months after the sampling event.
Quarterly Upload of Analytical Data to ERPIMS All analytical data collected basewide by the consultant are provided to Hill AFB in a quarterly ERPIMS electronic deliverable. These data include groundwater, surface water, water level, indoor air, soil, and other data collected at the sites during a specified date range. Data deliverables are quality checked before they are delivered to Hill AFB on CD.
SUMMARY The implementation of a residential sampling program requires a well-designed data management protocol so that residents receive accurate data in a timely fashion. The Basewide Residential Indoor Air Sampling Program at Hill AFB provides an example of a large-scale cooperative project with a successful data management protocol.
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ACKNOWLEDGEMENTS Concordia Communications, Inc.
REFERENCES 1
U.S. EPA Draft Guidance for Evaluating the Vapor Intrusion to Indoor Air Pathway from Groundwater and Soil; U.S. EPA, 2002. 2
EerNisse, P., Oliver, D., Steinmacher, S., Miller, J., Hall, B., Case, J. Relationships between Indoor Air Contaminant Concentrations and Site and Climatic Conditions; Air and Waste Management Association 101st Annual Conference & Exhibition, Portland, OR, June 24 - 27, 2008. 3
Kuehster, T., Folkes, D., and Wannamaker, E. Seasonal Variation in Observed Indoor Air Concentrations Due to Vapor Intrusion, Redfield Site, Colorado; Midwestern States Risk Assessment Symposium, Indianapolis, IN, August 26, 2004, http://iavi.rti.org/Resources.cfm?PageID=documentDetails&AttachID=74
KEY WORDS Data, management, ERPIMS, residential, database, residential data, communications
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