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The 7-Step DQO Process

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DQO Training Course Day 2 Module 11 The EPA 7-Step DQO Process Step 1 - State the Problem Presenter: Sebastian Tindall (90 minutes) (15 minute Morning Break) – PowerPoint PPT presentation

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Title: The 7-Step DQO Process


1
DQO Training Course Day 2Module 11
The EPA 7-Step DQO Process
Step 1 - State the Problem
Presenter Sebastian Tindall
(90 minutes) (15 minute Morning Break)
2
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)

3
Generic Flow Chart
Information IN Actions
Information OUT From Previous Step
To Next Step
Information OUT to Next Step
Information IN From Previous Step
Actions
4
Generic Flow Chart
Information IN Actions
Information OUT From Previous Step
To Next Step
Information OUT to Next Step
Information IN From Previous Step
Actions
Added information is presented in bubbles to
explain how to implement an action or explain
items to consider.
5
Examples
  • There are two types of examples found in this
    training
  • The general example

6
Step 1 State the Problem
  • Step Objective
  • To clearly define the Problem so that the focus
    of the Project will be unambiguous

Step 1 State the Problem
Step 2 Identify Decisions
Step 3 Identify Inputs
Step 4 Specify Boundaries
Step 5 Define Decision Rules
Step 6 Specify Error Tolerances
Step 7 Optimize Sample Design
7
Step 1a - State the Problem
Information IN Actions
Information OUT From Previous Step
To Next Step
Identify the DQO Team and define each members
roles and responsibilities
Identify available resources and relevant
deadlines
Planning Meeting
Continue activities
Identify the decision makers and define each
members roles and responsibilities
Identify the Stakeholders and determine who will
represent their interests
8
Step 1a - State the Problem
Information IN Actions
Information OUT From Previous Step
To Next Step
Identify the DQO Team and define each members
roles and responsibilities
Identify available resources and relevant
deadlines
  • The DQO Team is the technical group that
  • will develop the DQOs for the project
  • The number of members will be directly related
  • to the size and complexity of the problem

Planning Meeting
Continue activities
Identify the decision makers and define each
members roles and responsibilities
Identify the Stakeholders and determine who will
represent their interests
9
Step 1a - State the Problem
Information IN Actions
Information OUT From Previous Step
To Next Step
Identify the DQO Team and define each members
roles and responsibilities
  • DQO Team may
  • include
  • Chemist
  • Hydrogeologist
  • Engineer
  • Safety Specialist
  • Statistician
  • Modeler
  • Quality Assurance (QA)/ Quality Control
    (QC) Specialist
  • Etc.

Identify available resources and relevant
deadlines
Planning Meeting
Continue activities
Identify the decision makers and define each
members roles and responsibilities
Identify the Stakeholders and determine who will
represent their interests
10
DQO Team Members
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11
Step 1a - State the Problem
Information IN Actions
Information OUT From Previous Step
To Next Step
Identify the DQO Team and define each members
roles and responsibilities
Identify available resources and relevant
deadlines
Planning Meeting
Continue activities
Identify the decision makers and define each
members roles and responsibilities
  • Stipulate the anticipated budget, available
  • personnel, and contractual vehicles to be
    used
  • Enumerate any deadlines for completion of
  • the study and any intermediate deadlines that
  • may need to be met

Identify the Stakeholders and determine who will
represent their interests
12
Available Resources and Deadlines
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13
Budget and Milestones
  • As is the case in the example, budgets and
    schedules are often set without any systematic
    planning
  • It is preferred that the DQO Process be performed
    well before the budget and schedule are
    established
  • Budgets for implementing the DQO Process are a
    must
  • The results of the DQO Process can then be used
    to set the remaining project schedule and budget

14
Step 1a - State the Problem
Information IN Actions
Information OUT From Previous Step
To Next Step
Identify the DQO Team and define each members
roles and responsibilities
  • Have the ultimate authority for making final
    decisions basedon the recommendations of the DQO
    Team
  • Federal Facility
  • Environmental Protection Agency
  • State Regulatory Agency

Identify available resources and relevant
deadlines
Planning Meeting
Continue activities
Identify the decision makers and define each
members roles and responsibilities
Identify the Stakeholders and determine who will
represent their interests
15
Decision Makers
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Step 1a - State the Problem
Information IN Actions
Information OUT From Previous Step
To Next Step
Identify the DQO Team and define each members
roles and responsibilities
Identify available resources and relevant
deadlines
Planning Meeting
Continue activities
Identify the decision makers and define each
members roles and responsibilities
  • Decision Makers
  • Seek, consider, and represent the concerns of the
    Stakeholders

Identify the Stakeholders and determine who will
represent their interests
17
Step 1a - State the Problem
Information IN Actions
Information OUT From Previous Step
To Next Step
Identify the DQO Team and define each members
roles and responsibilities
Identify available resources and relevant
deadlines
Stakeholders are groups or individuals that will
be impacted by the decisions made as a result of
the DQO Process.
Planning Meeting
Continue activities
Identify the decision makers and define each
members roles and responsibilities
Identify the Stakeholders and determine who will
represent their interests
18
Stakeholders
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Step 1b - State the Problem
Information IN Actions
Information 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

Scoping Process Results Scoping Process Issues
Administrative and logistical elements
20
Remedial Action Soil Process Knowledge
  • Heli-101 flight pad used 1970-1995
  • Used to load, unload and maintain aircraft
  • Used oils and fuels spilled and washed off pad,
    draining to the surrounding soil
  • 1980 used as staging area for transformer and
    motor oils

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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

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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

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RI/FS Data Inorganics and TPH(surface soil
samples)
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RI/FS Data PCBs (surface soil samples)
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Areas to be Investigated
Plan View
Former Pad Location
Buffer Zone
Runoff Zone
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Summary of Spills and Releases
  • Pad is 75 in diameter
  • Add 50 to include the Run-off zone (d125)
  • 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
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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
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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
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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 98F
  • No endangered species
  • No cover or water collection system

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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

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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

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Step 1c - State the Problem
Information IN Actions
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

Note
Any differences in interviewees objectives,
requirements or concerns are listed as issues.
Continue activities
Specify interview issues
Scoping Process Results Scoping Process Issues
Hold Global Issues Meeting to resolve scoping and
interview issues
33
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.

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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.

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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.

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

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Step 1c - State the Problem
Information IN Actions
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

Global Issues Meeting Resolve any outstanding
scoping issues and/or interview issues with
decision makers.
Continue activities
Specify interview issues
Scoping Process Results Scoping Process Issues
Hold Global Issues Meeting to resolve scoping and
interview issues
38
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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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Step 1d - State the Problem
Information IN Actions
Information OUT From Previous Step
To Next Step
What are the COPCs?
How did COPCs arrive at site?
Develop Conceptual Site Model
How has fate transport affected site?
What is distribution of COPCs at site?
What are the decision drivers (risk? regulatory
limits? etc.)
49
Step 1d - State the Problem
Information IN Actions
Information 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
50
Step 1d - State the Problem
Information IN Actions
Information OUT From Previous Step
To Next Step
Identify COPCs
Provide rationale for COPC exclusions
Create final list of COPCs with rationale for
inclusions
  • Define the total list of COPCs
  • Identify
  • Source of contamination Reactor fuel rods
  • Type of contamination from each source Fission
    products
  • Specific COPCs Sr-90, Cs-137, etc.

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
51
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Step 1d - State the Problem
Information IN Actions
Information 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 COPC Exclusions
  • Develop rationale for the exclusion of any of
    the COPCs
  • Document the rationale for any exclusions
  • Example - Isotope with short half-life
  • - No health or ecological risk

Identify fate and transport mechanisms
List potential receptors
Problem Statement
Estimate COPC distributions
Discuss decision drivers
Write CSM Summary Narrative
53
Step 1d - State the Problem
Information IN Actions
Information 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
Consider the following questions 1. Was the
compound/element ever used at the site? 2. Does
the compound react with water and thus no longer
exist? 3. For waste, does the pH of the matrix
degrade the compound? 4. Is the compound volatile
and thus evaporate?
Identify fate and transport mechanisms
List potential receptors
Problem Statement
Estimate COPC distributions
Discuss decision drivers
Write CSM Summary Narrative
54
COPC Exclusions part 2
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Step 1d - State the Problem
Information IN Actions
Information 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
Identify the Final List of COPCs
List potential receptors
Problem Statement
Estimate COPC distributions
Discuss decision drivers
Write CSM Summary Narrative
56
Final List of COPCs
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Step 1d - State the Problem
Information IN Actions
Information 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
How the release occurred? Still occurring? Single
large release? Small release over long
time? Stack release of gases? Contaminated debris?
Problem Statement
Estimate COPC distributions
Discuss decision drivers
Write CSM Summary Narrative
58
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.

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Step 1d - State the Problem
Information IN Actions
Information OUT From Previous Step
To Next Step
Identify COPCs
Provide rationale for COPC exclusions
Begin to evaluate the fate transport of
COPCs Begin to evaluate the distribution of COPCs
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
60
Step 1d - State the Problem
  • Used to make assumption on the distribution
    (lateral/vertical) of COPCs
  • Dependent on
  • Types of COPCs expected
  • How they arrived
  • Amount of time since the release
  • Environmental conditions since the release
  • Effect of natural processes
  • Wind, weather, erosion, re-charge, etc.

Information IN Actions
Information 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
  • Types of sampling media
  • Soil
  • Concrete
  • Groundwater
  • Gravel
  • Etc.

Problem Statement
Estimate COPC distributions
Discuss decision drivers
Write CSM Summary Narrative
61
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 pads
    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.

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Step 1d - State the Problem
Information IN Actions
Information OUT From Previous Step
To Next Step
Identify COPCs
Provide rationale for COPC exclusions
  • Examples of receptors are
  • Humans
  • Plants
  • Animals

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
63
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).

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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.

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Potential Receptors (cont.)
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Step 1d - State the Problem
Information IN Actions
Information 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
Spatial and frequency distributions
Identify fate and transport mechanisms
List potential receptors
Problem Statement
Estimate COPC distributions
Discuss decision drivers
This is key point for determining the number of
samples
Write CSM Summary Narrative
67
Football Field
One-Acre
30'0"
Football Field
68
Spatial Distribution - Football Field
69
Probability Density Function
70
Step 1d - State the Problem
Information IN Actions
Information OUT From Previous Step
To Next Step
Identify COPCs
Provide rationale for COPC exclusions
Create final list of COPCs with rationale for
inclusions
Liquid spill ? Plume model (decreasing with
distance) Burn pit ? Lateral and vertical
heterogeneity Tank sludge ? Lateral
homogeneity/vertical heterogeneity Fill ? What
information is available about the fill? Concrete
? Drivers? Air Water Contact
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
71
Spatial Surface Soil Sample Results
A (18, 102, 4, 0.03)
B (27, 96, 3, 1.5)
Plan View
Former Pad Location
Buffer Zone
C (15, 78, 2.5, 0.03)
D (10, 86, 1, 2.0)
Runoff Zone
Letter sample point Concentrations (Pb, U, TPH,
Aroclor 1260)
E1 (12, 112, 0.03, 0.75)
E2 (15, 92, 0.03, 11)
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Distributions
  • 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.

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Frequency Distribution
74
Frequency Distribution
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Histogram
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Histogram (cont.)
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Histogram (cont.)
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Histogram (cont.)
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Distribution Curves
Mo ? Md ? Mn
Mo Md Mn
Lognormal
Normal
M0 mode Md median Mn mean
80
Step 1d - State the Problem
Information IN Actions
Information OUT From Previous Step
To Next Step
Identify COPCs
Provide rationale for COPC exclusions
Create final list of COPCs with rationale for
inclusions
Identify driver compounds (e.g., based on
greatest risk or movement or half-life) Examine
concentration range and compare to action
limit (e.g., far below or above action limit,
near action level)
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
81
Step 1d - State the Problem
Information IN Actions
Information OUT From Previous Step
To Next Step
Identify COPCs
  • Overall objectives of the project
  • Is the decision risk based?
  • Waste characterization based?
  • Regulatory restraints?
  • Future land uses?
  • Pilot study?
  • Remedial action?
  • Monitoring effort?
  • Characterization effort?
  • All potential data uses/users identified?

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
82
Decision Drivers
  • 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

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83
Step 1d - State the Problem
Use information gathered from the scoping
process, decision maker interviews and the
Global Issues Meeting to develop a CSM
Information IN Actions
Information 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
  • The CSM may be presented in the following forms
  • Narrative statement
  • Graphical
  • Tabular

Specify release mechanisms
Conceptual Site Model
Identify fate and transport mechanisms
List potential receptors
Problem Statement
The CSM narrative summary states clearly the
current understanding of the condition of the
site
Estimate COPC distributions
Discuss decision drivers
Write CSM Summary Narrative
84
CSM Narrative
  • 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...)

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CSM Spatial Graphical
Plan View
Former Pad Location
Buffer Zone
Runoff Zone
Section View
Former Pad Location
Buffer Zone
Grade Level
Runoff Zone
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Overview of the Receptor Pathway(CSM) Tabular
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87
Step 1d - State the Problem
Information IN Actions
Information 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
The goal of the DQO Process is to develop a
sampling design that will confirm or reject the
CSM.
List potential receptors
Problem Statement
Estimate COPC distributions
Discuss decision drivers
Write CSM Summary Narrative
88
Problem Statements
  • The CSM is used to constrain the problem
    statement(s)
  • The Problem Statement(s) allows the planning to
    be focused on issues that must be resolved with
    data and makes the problem unambiguous

89
Step 1d - State the Problem
Information IN Actions
Information 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
  • A concise problem statement describes
  • The problem as it is currently understood
  • The conditions that are causing the problem

Conceptual Site Model
Identify fate and transport mechanisms
List potential receptors
Problem Statement
Estimate COPC distributions
Discuss decision drivers
Write CSM Summary Narrative
90
Problem Statement Format
  • General Format
  • In order to achieve one of the objectives of
    this study data regarding general type of
    contamination are needed.

91
Problem Statement Examples
  • In order to confirm that the on-site in-situ
    GC/MS analysis can replace method 8260B results
    for use in final verification of closure, data
    regarding volatiles using both methods are
    needed.
  • In order to determine whether the concrete should
    be disposed at a TSCA incinerator, data regarding
    the PCBs in the concrete surface are needed.

92
Typical Problem Statement Example (YUCK!)
  • Process knowledge indicates that there would have
    been low plutonium concentrations in the wastes
    disposed through the tank and relatively few
    other radionuclides should be present. Limited
    sampling of the sludge indicates that plutonium
    is distributed within strata throughout the tank
    however, this distribution is somewhat
    heterogeneous and ill-defined. Characterization
    data are required to evaluate the need for an
    early removal action and, as required, to
    determine the appropriate methods for (1) removal
    of the sludge from Tank Y, (2) stabilization and
    packaging of the waste, and (3) sludge disposal.

93
Problem Statement Example
  • In order to show that lead is contributing to
    the decrease in duck populations in the wetlands
    data regarding levels of lead in the surface
    water, sediments, and vegetation in the
    marshlands are needed.

94
Problem Statement
  • 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.

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Step 1 Summary
  • Scoping is the most important activity
  • Adequate resources (time, money, people) must be
    provided for scoping
  • Adequate resources must be provided for the DQO
    Process
  • Identify the decision makers objectives,
    requirements, and concerns
  • Performing interviews allows the facilitator to
    understand each decision makers objectives and
    requirements
  • Resolving global issues allows technical staff to
    focus on providing defensible designs

96
Step 1 Summary (cont.)
  • Global issues include land use and interpretation
    of regulations
  • Logic for inclusion and exclusion of COPCs must
    be documented
  • It is possible to greatly decrease the number of
    COPCs based on sound technical logic
  • Remember, if there is no receptor there is no
    risk
  • CSM is based on scoping
  • The DQO Process goal is to test the CSM
  • CSM allows one to focus on problems that are
    resolved by data/information

97
Step 1a - State the Problem
Information IN Actions
Information OUT From Previous Step
To Next Step
Identify the DQO Team and define each members
roles and responsibilities
Identify available resources and relevant
deadlines
Planning Meeting
Continue activities
Identify the decision makers and define each
members roles and responsibilities
Identify the Stakeholders and determine who will
represent their interests
98
Step 1b - State the Problem
Information IN Actions
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

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
99
Step 1c - State the Problem
Information IN Actions
Information 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
100
Step 1d - State the Problem
Information IN Actions
Information 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
101
End of Module 11
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