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The EPA 7-Step DQO Process

DQO Training Course Day 3 Module 18. The EPA 7-Step DQO Process. Step 1 – Problem Statement DQO Case Study. Presenter: Sebastian Tindall. 45 minutes. DQO Case Study. Heli-101 Flight Pad. Step 1a - State the Problem. Information IN Actions Information OUT

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The EPA 7-Step DQO Process

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  1. DQO Training Course Day 3Module 18 The EPA 7-Step DQO Process Step 1 – Problem StatementDQO Case Study Presenter: Sebastian Tindall 45 minutes

  2. DQO Case Study Heli-101 Flight Pad

  3. Step 1a - State the Problem Information INActionsInformation OUT From Previous Step To Next Step Identify the DQO Team and define each member’s roles and responsibilities Identify available resources and relevant deadlines Planning Meeting Continue activities Identify the decision makers and define each member’s roles and responsibilities Identify the Stakeholders and determine who will represent their interests

  4. Step 1b - State the Problem Information INActionsInformation OUT From Previous Step To Next Step • Scoping Process Results: • Collect site history, process knowledge, • Summarize existing analytical data • Specify areas to be investigated • Summarize all recorded spills and releases • Document applicable regulations • Current housekeeping practices • Current local environmental conditions Administrative and logistical elements Continue activities

  5. Step 1c - State the Problem Information INActionsInformation OUT From Previous Step To Next Step • Conduct interviews with decision makers and Stakeholders to determine their: • Objectives • Requirements (applies to decision makers only) • Concerns Scoping Process Results Scoping Process Issues Specify interview issues Scoping Process Results Scoping Process Issues Hold Global Issues Meeting to resolve scoping and interview issues

  6. Step 1d - State the Problem Information INActionsInformation OUT From Previous Step To Next Step Identify COPCs Provide rationale for COPC exclusions Create final list of COPCs with rationale for inclusions Scoping Process Results Scoping Process Issues Global Issues Resolutions Specify release mechanisms Conceptual Site Model Identify fate and transport mechanisms List potential receptors Problem Statement Estimate COPC distributions Discuss decision drivers Write CSM Summary Narrative

  7. 2 Approaches • Approach 1: Traditional lab methods • Approach 2: Field analytical methods with final confirmation via lab methods • Select onsite methods that focuses on driver COPCs (e.g., risk drivers, transport drivers, etc.)

  8. 2 Approaches Approach 1 Use predominantly fixed traditional laboratory analyses and specify the method specific details at the beginning of the DQO Process and do not change measurement objectives as more information is obtained This approach will contain serious flaws. Note: Students are expected to point out these flaws as the class progresses.

  9. 2 - Approaches (cont.) Approach 2 Allow more field decisions to meet the measurement objectives and allow the objectives to be refined in the field using dynamic work plans (Managing Uncertainty approach) This approach will attempt to overcome the serious flaws shown in Approach 1.

  10. 2 - Approaches (cont.) • Approach 2 - Dynamic Work Plans • Real-time, decision making in the field allows for a seamless flow of site activities resulting in fewer mobilizations • Requires more flexible contracting approach • Requires experienced, well-trained field team (e.g., geologists, chemists and statisticians) either in the field or able to receive and process electronic data in real-time

  11. 2 - Approaches (cont.) • Approach 2 • Allows collection of more data in real-time • Allows real-time decisions to be made • Must have flexible but established decision trees approved by decision makers ahead of time • Need general statements of measurement quality that will be interpreted by field team • May be more costly due to higher level of expertise required but…more defensible • Overcomes the Classical Statistical Burdens

  12. Objective Based on comprehensive Scoping, to be able to develop, for a specific project: 1. a list of Contaminants of Potential Concern, 2. a conceptual site model (CSM), 3. a problem statement(s)

  13. DQO Team Members

  14. Available Resources and Deadlines

  15. Decision Makers

  16. Stakeholders

  17. Remedial Action Soil Process Knowledge • Heli-101 flight pad used 1970-1995 • Used to load, unload and maintain aircraft • Wash down and maintain vehicles • Used oils and fuels spilled and washed off pad, draining to the surrounding soil • 1980 used as staging area for transformer and motor oils

  18. Remedial Action Soil Process Knowledge (cont.) • 1990s used as area to decon equipment from the Gulf War • Collection sump used to capture pad rinsate from Gulf War • Equipment was washed to remove depleted uranium • 1995 trace uranium found on pad

  19. Summary of Existing Data • ALL data collected from surface soil (0-6”) • Summary of existing total petroleum hydrocarbon (TPH) data • See next table • All TPHs were below regulatory limit of 100 mg/kg • PCBs detected in 2 of 5 samples and were above state limit of 1 mg/kg • No other volatiles, semivolatiles, or metals (excluding Pb, U) were detected above background • The Base ground and surface water have not detected contamination

  20. RI/FS Data –Inorganics and TPH(surface soil samples)

  21. RI/FS Data –PCBs (surface soil samples)

  22. 0 50 100 150 ft 0 15 30 46 m Areas to be Investigated Plan View Former Pad Location Buffer Zone Runoff Zone

  23. Summary of Spills and Releases* • Pad is ~75’ in diameter • Add 50’ to include the Run-off zone (d=125’) • Buffer zone is ~265’ in diameter, with Pad centered within • Area of Pad is 4,418 ft2 • Area of Pad + Run-off zone = 12,272 ft2 • Area of Buffer zone is 42,884 ft2 (excluding Pad and Run-off zone) *Does not include layback area

  24. Summary of Spills andReleases* (cont.) • Volume of Pad & Run-off zone, 0-6”, is 227 yd3 • Volume of Buffer zone, 0-6”, is 794 yd3 (excluding Pad and Run-off zone) • Volume of Pad & Run-off zone, 6”-10’, is 4,318 yd3 • Volume of Buffer zone, 6”-10’, is 15,089 yd3 (excluding Pad and Run-off zone) *Does not include layback area

  25. Summary of Spills andReleases* (cont.) • No releases recorded before 1977 (e.g., before adopting RCRA) • Drum inventories from 1980s were imprecise • Reports from 1990s were sparse and not declassified. One report did include uranium data from the sump at 450 mg/L. • Interviews indicate that predominant metals were Pb and U. U was depleted. *Does not include layback area

  26. Current Conditions • Housekeeping practices • physically barricaded to prevent use • Site conditions and local environment • Pad is removed, land is barren without vegetation • Avg. rainfall ~20 in./yr • Groundwater at ~50 ft below grade • Temperatures range 12 to 98°F • No endangered species • No cover or water collection system

  27. Current Conditions (cont.) • Areas to be investigated: • exclude surface or groundwater • exclude biota (covered by overall base program) • include soil via direct exposure • include soil area/volume

  28. Scoping Issues • The degree and extent of soil contamination reported from the RI/FS is questionable • There are different opinions as to whether multiple constituents of interest exist and whether the constituents are present above regulated levels at the site

  29. Interview Issues • Shipment of wastes from the base could impact the local community: Local authorities expressed a concern over the transport of hazardous materials from the Base. Of particular concern was the impact to community traffic flow and the potential for an accidental release.

  30. Interview Issues (cont.) • Suitability/protectiveness of cleanup standards:Current State regulations regarding cleanup levels have been questioned by local stakeholders (special interest groups) as to their degree of protectiveness. Current special interest groups have argued that contamination, at any level, poses an unnecessary and unacceptable threat to human health and the environment. These special interest groups have asserted that the Base has a moral obligation to remove all detectable contamination in order to ensure that the surrounding community and wildlife is protected.

  31. Interview Issues (cont.) • Schedule delays, cost overruns, lack of sufficient sample data:The Base has expressed concerns over the involvement of special interests, particularly, those who would require that the Base perform potentially unneeded cleanup operations that are well beyond the scope and intent of the law. The Base has also expressed a concern that the operation be managed within the schedule and costs for which the project has been assigned. There is also a need to collect data that will be sufficient for its intended purpose; site closure/risk assessment input, or, designation of the waste for cleanup and disposal.

  32. Interview Issues (cont.) • Land Use: • Base commander believes land use is industrial • EPA believes land use should be residential

  33. Global Issues Meeting • Scoping Issue: • The degree and extent of soil contamination reported from the RI/FS is questionable • Resolution: • Currently available historical information (existing data) was collected with the intent to characterize the site for disposal according to RI/FS considerations. However, such characterization data are not sufficient to support a decision for site closure or a decision to conduct additional remedial action if deemed necessary.

  34. Global Issues Meeting (cont.) • Interview Issue: • Shipment of wastes from the Base could impact the local community: Local authorities expressed a concern over the transport of hazardous materials from the Base. Of particular concern was the impact to community traffic flow and the potential for an accidental release.

  35. Global Issues Meeting (cont.) • Resolution: • The only quantities planned for off-site shipment are small quantities of slightly contaminated soil and/or water that would be sent to an independent analytical laboratory. Large shipments of hazardous substances are not planned. All Department of Transportation regulations will be followed as applicable. Shipments will be timed for off-peak traffic hours. If a large-scale soil remediation project is spawned as a result of the sampling effort, waste shipments will be planned at that time, and in such a way as to minimize the impact to the community.

  36. Global Issues Meeting (cont.) • Interview Issue: • Suitability/protectiveness of cleanup standards: Current State cleanup standards are questioned by the interest groups. The concern is that the standards are not protective of the wild life and community. • Resolution: • The State and Federal agencies have explained the risk assessment process to the interest groups. Compliance with these risk levels will be protective. The State has encouraged the special interest groups to take their concerns to the legislature. Based on more information related to the risk assessment process, the interest groups indicated that the approach was logical.

  37. Global Issues Meeting (cont.) • Interview Issue: • Schedule delays, cost overruns, lack of sufficient sample data: The Base has expressed concerns over the involvement of special interests, particularly, those who would require that the Base perform potentially unneeded cleanup operations that are well beyond the scope and intent of the law. The Base has also expressed a concern that the operation be managed within the schedule and costs (presented later in this example) for which the project has been assigned. There is also a need to collect data that will be sufficient for its intended purpose; site closure/risk assessment input, or, designation of the waste for cleanup and disposal.

  38. Global Issues Meeting (cont.) • Resolution: • The Base is relying on the DQO Process to determine the most cost-effective and technically defensible means for collection of samples. The DQO Process will specify the decision makers’ tolerable limits on decision errors, which are used for limiting uncertainty in the data and therefore reduce the chance of unnecessary cleanup. Furthermore, the Base will be using the DQO Process to document agreement of the sampling strategy with the regulators and local community as a means of reducing base liability. The SAP generated from the DQO effort will result in data collection sufficient for its intended purpose.

  39. Global Issues Meeting (cont.) • Interview Issue: • Data will not be of sufficient quality for risk assessment: Regulators are concerned that previous data are not of the quality to support risk assessment. • Resolution: • Regulators will be participants in the DQO Process which defines the data and quality requirements. In addition, they may take split samples at the same time sampling is performed.

  40. Global Issues Meeting (cont.) • Interview Issue: • Conflicting land uses (industrial vs. residential): Regulators believe the land use is residential which decreases the allowable risk (10-6 as opposed to 10-5) and may result in allowing higher concentrations to remain in the soil. Base command believes the land use is industrial.

  41. Global Issues Meeting (cont.) • Resolution: • For all government facilities a federal facility agreement (FFA) is signed between the EPA/State and the federal agency that owns the site (e.g., DOE or military). By law, this agreement indicates that the federal agency owning the site can designate the land use or agree to negotiate the land use. The FFA indicated that the military would designate the land use, thus, it will be industrial.

  42. COPC Exclusions; part 2

  43. Final List of COPCs

  44. Release Mechanisms • How the COPCs arrived at the site Motor pool type supplies and products were transported to the site to aid in maintenance operations. Transformers containing PCBs were stored at the site. COPCs were typically washed from spills on the helicopter pad and into the surrounding soil.

  45. Fate and Transport • How has fate and transport mechanisms affected the COPCs The soil is suspected of being contaminated by spilled material that leaked or was washed from the pad at various times during the pad’s history. The physical components of the site include surface and subsurface soils and gravel within the known boundaries of the spill. Unimpeded access is assumed for all sampling media. Because the site has been exposed to weather (precipitation) since the spill occurrences, some transport into the subsurface is likely to have occurred; therefore, to support clean site confirmation, the underlying soil is included within the boundaries of the site.

  46. Receptors • Future land use • It is anticipated that the land must be released for industrial use at some future time. Therefore, potential receptors include human workers as well as the surrounding biota (e.g., shrubbery).

  47. Potential Receptors • Data for groundwater wells on the military base have not indicated contamination attributable to this site • This leads one to believe that there is no groundwater contamination, thus the groundwater ingestion pathway is not complete and does not require added investigation. Industrial workers will use sanitary water from the city.

  48. Potential Receptors (cont.)

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