1. 1 of 63 The EPA 7-Step DQO Process Step 1 – Problem Statement DQO Case Study Presenter: Sebastian Tindall 45 minutes DQO Training Course Day 3 Module 18

2. 2 of 63 DQO Case Study Heli-101 Flight Pad

3. 3 of 63 Information INActions Information OUT From Previous Step To Next Step Identify the DQO Team and define each member’s roles and responsibilities Continue activities Identify the decision makers and define each member’s roles and responsibilities Identify the Stakeholders and determine who will represent their interests Planning Meeting Identify available resources and relevant deadlines Step 1a - State the Problem

4. 4 of 63 Information INActions Information OUT From Previous Step To Next Step Continue activities 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 Step 1b - State the Problem

5. 5 of 63 Information INActions Information 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 Specify interview issues Hold Global Issues Meeting to resolve scoping and interview issues Scoping Process Results Scoping Process Issues Step 1c - State the Problem Scoping Process Results Scoping Process Issues

6. 6 of 63 Information INActions Information OUT From Previous Step To Next Step Scoping Process Results Scoping Process Issues Global Issues Resolutions Conceptual Site Model Problem Statement Estimate COPC distributions Provide rationale for COPC exclusions Create final list of COPCs with rationale for inclusions Specify release mechanisms Identify fate and transport mechanisms List potential receptors Discuss decision drivers Write CSM Summary Narrative Identify COPCs Step 1d - State the Problem

7. 7 of 63 2 Approaches n Approach 1: Traditional lab methods n 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. 8 of 63 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. 9 of 63 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. 2 - Approaches (cont.)

10. 10 of 63 n 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 2 - Approaches (cont.)

11. 11 of 63 n 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 2 - Approaches (cont.)

12. 12 of 63 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. 13 of 63 DQO Team Members

14. 14 of 63 Available Resources and Deadlines

15. 15 of 63 Decision Makers

16. 16 of 63 Stakeholders

17. 17 of 63 Remedial Action Soil Process Knowledge n Heli-101 flight pad used 1970-1995 n Used to load, unload and maintain aircraft n Wash down and maintain vehicles n Used oils and fuels spilled and washed off pad, draining to the surrounding soil n 1980 used as staging area for transformer and motor oils

18. 18 of 63 n 1990s used as area to decon equipment from the Gulf War n Collection sump used to capture pad rinsate from Gulf War n Equipment was washed to remove depleted uranium n 1995 trace uranium found on pad Remedial Action Soil Process Knowledge (cont.)

19. 19 of 63 Summary of Existing Data n ALL data collected from surface soil (0-6”) n Summary of existing total petroleum hydrocarbon (TPH) data n See next table n All TPHs were below regulatory limit of 100 mg/kg n PCBs detected in 2 of 5 samples and were above state limit of 1 mg/kg n No other volatiles, semivolatiles, or metals (excluding Pb, U) were detected above background n The Base ground and surface water have not detected contamination

20. 20 of 63 RI/FS Data –Inorganics and TPH (surface soil samples)

21. 21 of 63 RI/FS Data –PCBs (surface soil samples)

22. 22 of 63 Areas to be Investigated Plan View Former Pad Location Runoff Zone 050100150 ft 01530 46 m Buffer Zone

23. 23 of 63 Summary of Spills and Releases* n Pad is ~75’ in diameter n Add 50’ to include the Run-off zone (d=125’) n Buffer zone is ~265’ in diameter, with Pad centered within n Area of Pad is 4,418 ft 2 n Area of Pad + Run-off zone = 12,272 ft 2 n Area of Buffer zone is 42,884 ft 2 (excluding Pad and Run-off zone) *Does not include layback area

24. 24 of 63 n Volume of Pad & Run-off zone, 0-6”, is 227 yd 3 n Volume of Buffer zone, 0-6”, is 794 yd 3 (excluding Pad and Run-off zone) n Volume of Pad & Run-off zone, 6”-10’, is 4,318 yd 3 n Volume of Buffer zone, 6”-10’, is 15,089 yd 3 (excluding Pad and Run-off zone) *Does not include layback area Summary of Spills and Releases* (cont.)

25. 25 of 63 n No releases recorded before 1977 (e.g., before adopting RCRA) n Drum inventories from 1980s were imprecise n Reports from 1990s were sparse and not declassified. One report did include uranium data from the sump at 450 mg/L. n Interviews indicate that predominant metals were Pb and U. U was depleted. *Does not include layback area Summary of Spills and Releases* (cont.)

26. 26 of 63 Current Conditions n Housekeeping practices –physically barricaded to prevent use n 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. 27 of 63 n Areas to be investigated: –exclude surface or groundwater –exclude biota (covered by overall base program) –include soil via direct exposure –include soil area/volume Current Conditions (cont.)

28. 28 of 63 Scoping Issues n The degree and extent of soil contamination reported from the RI/FS is questionable n 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. 29 of 63 Interview Issues n 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. 30 of 63 n 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. Interview Issues (cont.)

31. 31 of 63 n 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. Interview Issues (cont.)

32. 32 of 63 n Land Use: –Base commander believes land use is industrial –EPA believes land use should be residential Interview Issues (cont.)

33. 33 of 63

34. 34 of 63 Global Issues Meeting n Scoping Issue: –The degree and extent of soil contamination reported from the RI/FS is questionable n 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.

35. 35 of 63 n 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. Global Issues Meeting (cont.)

36. 36 of 63 n 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. Global Issues Meeting (cont.)

37. 37 of 63 n 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. n 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. Global Issues Meeting (cont.)

38. 38 of 63 n 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. Global Issues Meeting (cont.)

39. 39 of 63 n 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. Global Issues Meeting (cont.)

40. 40 of 63 n 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. n 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. Global Issues Meeting (cont.)

41. 41 of 63 n 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. Global Issues Meeting (cont.)

42. 42 of 63 n 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. Global Issues Meeting (cont.)

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44. 44 of 63 COPC Exclusions; part 2

45. 45 of 63 Final List of COPCs

46. 46 of 63 Release Mechanisms n 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.

47. 47 of 63 Fate and Transport n 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.

48. 48 of 63 Receptors n 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).

49. 49 of 63 n Data for groundwater wells on the military base have not indicated contamination attributable to this site n 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. Potential Receptors

50. 50 of 63 Potential Receptors (cont.)

51. 51 of 63 Spatial Surface Soil Sample Results B (27, 96, 3, 1.5) D (10, 86, 1, 2.0) E2 (15, 92, 0.03, 11) E1 (12, 112, 0.03, 0.75) C (15, 78, 2.5, 0.03) A (18, 102, 4, 0.03) Letter = sample point Concentrations (Pb, U, TPH, Aroclor 1260) Plan View Former Pad Location Runoff Zone 050100150 ft 01530 46 m Buffer Zone

52. 52 of 63 Distributions n Presumed Spatial Distributions of the COPCs –The pad was washed, and therefore the area where the edge of the pad once existed is likely to have higher concentrations than the area further away from the previous edge of the pad. It cannot be assumed that contamination decreases with depth from the surface. However, contamination is expected to decrease with depth; therefore, deeper soils are assigned a lower probability of being contaminated. –The probability of contamination will be scaled within a range bounded by the arbitrary lateral and vertical boundary to be determined during sample optimization (Step 7). This is because the amount of data collected from the RI/FS is not sufficient to define the physical boundaries of the expected residual contamination. The previous RI/FS did not use the DQO Process.

53. 53 of 63 Frequency Distribution

54. 54 of 63 Histogram

55. 55 of 63 Histogram (cont.)

56. 56 of 63 Histogram (cont.)

57. 57 of 63 Histogram (cont.)

58. 58 of 63 Decision Drivers n Future land use –Effect of residual contamination on the ecosystem was not previously considered –Direct long-term industrial land use was not considered in the past risk models –All parties agreed to use industrial land use as the scenario –If concentrations are below the levels based on industrial use, the remediation will be complete, otherwise added remediation will be needed

59. 59 of 63 CSM Narrative n The Heli-101 Pad and the surrounding soil (surface and underlying) extending laterally up to  95 ft in any direction from the perimeter of the pad and up to a depth of 10 ft constitutes the conceptual model for the contaminated site. It is graphically depicted in the plan view and section view in the following section. Surface soil is defined as soil up to a depth of 6 in. and underlying (subsurface) soil is defined as soil up to a further depth of 10 ft. (Etc.………………………………………..)

60. 60 of 63 Plan View Section View Former Pad Location Runoff Zone 050100150 ft 0153046 m Former Pad Location Runoff Zone Grade Level 050100150 ft 01530 46 m Vertical not to scale Buffer Zone CSM Spatial Graphical Buffer Zone 60 of 101

61. 61 of 63 Overview of the Receptor Pathway (CSM) Tabular

62. 62 of 63 n In order to determine whether the residual soils at the site are contaminated, data regarding potential contaminants in the surface and underlying soils are needed. Problem Statement

63. 63 of 63 End of Module 18 Thank you Questions?