Transcript VRP Outreach

Cross Section
Contaminant Iso Map
Data Tables
• Well presented data tables communicate a lot of
information at a glance
• Easier to draw conclusions when well organized
and presented
• Having to scour reports to mine out data to draw
conclusions is time consuming
– DEQ may not get an accurate picture or understanding
• May not reach the same conclusion
– Often results in comment letters
• Line charts illustrating concentrations over time
– Show each contaminant
• PCE, TCE, DCE, VC
Well Gauging Data Table
Groundwater Sampling Results Table
Groundwater Sampling Results Table Notes
Soil Sampling Results Table
Data Presented Graphically
SCR Tips
• Delineate plume at least to the MCL /screening level (i.e. show 5.0 ug/L isocon
for PCE) but delineating to the detection limits is preferred.
• If plume is migrating off-site, then collect off-site samples if possible. At a
minimum collect samples from each media at downgradient site boundary
• Delineate each constituent of concern.
• Gauge wells prior to each sampling event.
• Gauge and sample all wells on the same day or as close as possible.
• Take surface soil samples
• Sample the source not beside it
• Put revision dates on figures
• Put date of sampling events on delineation figures
• Act upon DEQ comments as soon as possible to keep process moving
• Analyze broad suite of compounds initially before ruling out constituents
SCR Tips
• Multiple rounds of sampling to account for variability and to assess plume
stability
• Initial GW sampling can be from direct push (geoprobes), however
permanent monitoring wells are preferred to provide comparable timeseries data at same location
• Incorporate data from historical reports into the text, tables and figures of
SCR
• Do not forget about historic petroleum releases. Sample for VOCs, SVOCs,
TAL metals, PCBs (if applicable)
• Aquifer tests to obtain site specific flow velocity
• Discuss fate and transport, plume stability
• Describe/document field procedures and protocols
• Collect sub-slab samples (soil, soil-gas) at dry cleaners (VOC) sites
Questions?
Lunch
VRP Checklist
Risk Assessment, RAWP, & Certificate
Presented by:
Patricia McMurray – Risk Assessment Program Manager
Sonal Iyer – Risk Assessor
Kyle Newman – Risk Assessor
Chris Evans – VRP Project Officer
William Lindsay – VRP Project Officer
RAP Staff
• Pat McMurray
[email protected]
• Kyle Newman
[email protected]
• Sonal Iyer
[email protected]
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Remediation Programs
Voluntary
Remediation Program
Risk Assessment
Brownfields
Program
Program
RISK ASSESSMENT PROCESS
PROBLEM FORMULATION
DATA COLLECTION AND EVALUATION
EXPOSURE ASSESSMENT
TOXICITY ASSESSMENT
RISK CHARACTERIZATION
RISK MANAGEMENT
Modified from Risk Assessment
Guidance for Superfund (EPA 1989)
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Risk Goals
• Carcinogens
– Probability of developing cancer
– 1 x 10-6 to 1 x 10-4 acceptable risk
• Non-Carcinogens
– Hazard quotient=
site exposure/acceptable exposure
– Hazard index=sum of hazard quotients
– Hazard index of 1 or below is acceptable
VRP Risk Assessment Guidance
• Streamlines the review process
• Insures that DEQ has the info we need
• www.deq.virginia.gov/vrprisk
VRP Checklist - Data Evaluation
• Methods used able to detect compounds at
screening levels?
• Are all detected chemicals included in screening?
• Screening performed for current and potential onsite receptors?
• Results compared to background? (optional)
• Potential for off-site risks screened?
Data Evaluation Screening
• Tier 1-Background
• Tier 2-Unrestricted
• Tier 3-Restricted
Risk Characterization
• Carcinogens
– Slope factor or Unit Risk x Exposure
– 1 x 10-6 to 1 x 10-4 acceptable risk
• Non-Carcinogens
– Hazard quotient=
site exposure/reference dose
– Hazard index=sum of hazard quotients
– Hazard index of 1 or below is acceptable
VRP Checklist - Risk Characterization
• Risk and hazard results presented for all COPCs for
all exposure pathways?
• Have total risk and hazard results been presented
for all COPCs for each receptor?
• Are target organ-specific hazards indices calculated
if the HI exceeds 1?
• Uncertainty assessment included?
Risk Characterization
• Tables 5.1-5.14
– Risks and hazards for each receptor by media
• Calculation Tools
– Example gwcalcs
• Tables 5.15-5.22
– Total risks and hazards for each receptor
Risk Characterization Uncertainty
Assessment
• Data Collection and Evaluation
# and type of samples
• Exposure Assessment
max or UCL, exposure factors
• Toxicity Assessment
values that are under review
Risk Characterization
Reality Check
Vapor Intrusion Review
• Data Collection and Evaluation
– Groundwater-Table 2.10
– Deep Soil Gas-Table 2.11
– Subslab-Table 2.12
– Indoor air-maybe
– Screen for both on and off site
Vapor Intrusion Review
• Exposure Assessment
– On and Off Site-Table 3.1 a and 3.1b
– Current and Future
Vapor Intrusion Review
• Lines of Evidence
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Horizontal and vertical extent of contamination
Comparison of groundwater, subslab, and soil gas
Seasonal variation and trends over time
Groundwater flow direction and velocity
Downgradient Land Use
Distance to receptors
Preferential pathways
Comparison of source to downgradient
concentrations
VRP Checklist - Remediation Levels
• Remediation levels calculated when
remediation is required?
• Tables 6.1-6.4
Questions?
Remedial Action Work Plans
• How will the proposed remedial action accomplish goals
• VRP provides flexibility with timing of remedial activities
– Can proceed with remedial action without DEQ approval
– DEQ will generally be interested in maximum source removal
– Follow up later to inform us what was done
• Photos, lab analyses, trucking manifests, etc are helpful
• If only Institutional Controls are suggested, dedicate a section in
the Risk Assessment to describing them and how they will be
protective
– Note that residential use restrictions also prohibit children’s day care,
schools and playgrounds (hotels and motels are OK)
• However, prepare a separate RAWP if actual remediation if
planned
• Provide rationale for remedial strategies considered but not used
• Include specific, surveyed no-dig locations
Remedial Action Work Plans cont.
• If using chemical injections adequately discuss
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Was the correct stuff used
Was it used properly
Was enough used
Will it last long enough to accomplish cleanup goals
What results should we expect
• Frequency of confirmatory sampling and for which constituents
• Provide adequate reasoning when relying on natural attenuation
• Drawing and specs for remediation systems are helpful
– SVE, SSDS, etc
• Any required O&M Plans (e.g. SSDS), and/or HASPs etc. must be
submitted at this point
Remediation System Schematic
Remediation System Plan View
Remediation System Detail
Remediation System Detail
Remediation System Detail
Remediation System Detail
Remediation System Detail
Questions?
Demonstration of Completion
9 VAC 20-160-70.A.4.a-b.
• DOC is a separate document/report submitted after the remediation (per the
approved Remedial Action Plan) is complete
• Must include a detailed summary of the performance of the remediation. Summary
should also include actions taken to investigate the release. Land-use controls are
considered remediation
• Must include (if applicable) confirmational sampling results demonstrating
that…established remedial objectives have been achieved, or that other criteria for
completion of remediation have been satisfied (e.g. post-excavation soil samples
or post-remediation groundwater samples showing achievement of remediation
levels and plume stability, measurements confirming the radius of influence of
SSDS etc.)
• Must include the total cost of remediation so that the registration fee paid upfront
can be reconciled. Any additional balance owed by the participant must be paid at
this point (prior to issuance of the Certificate). If a refund is owed to the
participant, it will be process at the time of Certificate issuance
• The participant must certify compliance with applicable regulations pertaining to
VRP activities (this includes items such as waste management and disposal, erosion
and sedimentation control, air emissions controls, wetlands, permits, underground
injection control ‘rule authorization’ from EPA, etc.)
DOC – SSDS Radius of Influence
Data Presented Graphically
Public Notice 9 VAC 20-160-120
• Participants must give notice of the proposed or completed voluntary remediation
• Notice is made after DEQ concurs with the SCR and the proposed remediation, but
prior to issuing the Certificate.
• Performed and paid for by the participant, not DEQ. DEQ is not the point of
contact listed on the Public Notice.
• Written notice is provided to the local gov’t, all adjacent property owners
(including VDOT if applicable), and published once in a local newspaper
• We recommend also notifying any party with property interests that are affected
by the use restrictions. (e.g. utility easements, mortgage holders)
• ‘Adjacent’ is interpreted by DEQ to include properties across a roadway from the
site
• A 30-day comment period follows issuance of the notice
• Contents of the notice must include: name and address of the participant, location
of the voluntary remediation, brief description of the remediation, general nature
of the release, any proposed land-use controls, address and telephone number of a
specific contact person to obtain information (not DEQ), and a brief description of
how to submit comments
Public Notice - 9 VAC 20-160-120
• Provide to DEQ: a signed statement from the participant that a
written notice was sent to all adjacent property owners, and the
local government; a copy of the notice, and a list of all names and
addresses to whom the notice was sent
• Participant shall send all commenters a letter acknowledging
receipt of comments
• Provide to DEQ: copies of all written comments received, copies of
acknowledgment letters, a discussion of how comments were
considered, copy of response to comments, a discussion of their
impact on the proposed or completed remediation
• Documentation should be assembled and submitted in one
package after the comment period is complete, usually (but not
necessarily) as part of the Demonstration of Completion
Certification of Satisfactory
Completion of Remediation
• 9 VAC 20-160-110
• The Certificate grants immunity to the participant, owner
and future owners of the site from enforcement actions
under state law
• Immunity is limited to conditions documented at the time
of issuance. Certificate can be revoked if new information
arises indicating a risk to human health or the environment
• Certificate is issued after the participant has demonstrated:
that migration of the contamination has been stabilized,
that the site has met remediation levels and will continue
to meet remediation levels in the future for both on site
and off site receptors, and the department concurs with all
work submitted pursuant to the VRP regulation
Certificate
• Much of the information in the Certificate must come from the
participant, which is why DEQ requests the participant create the
initial draft of the Certificate. It is a collaborative effort
• Guidance and a Model Certificate (available on VRP website) have
been developed to facilitate drafting of the Certificate
• The Model Certificate represents the standard format and
language, approved by the Virginia Attorney General’s Office, to be
followed for all sites. No deviations from the model should be
expected
• If unique circumstances exist requiring a deviation from the
standard language, then it will need to be reviewed and approved
by DEQ legal staff. There is no guarantee it will be acceptable
Certificate
• Be sure to include a surveyed plat and metes and bounds
description of the site with the draft Certificate
• If land use restrictions are specified in the Certificate, they
must be included in a Declaration of Restrictive Covenants
(Declaration) and attached to the Certificate.
• The Declaration is a legally binding document that must be
recorded with the deed of a site to restrict use of the site
• The current landowner and all future landowners of the
site will be obligated to comply with the restrictions
• Any party with property interests that are affected by the
land use restrictions must be listed on the Certificate under
‘Encumbrances’, and also sign the Declaration. Examples
could include mortgage holders, utility right-of-ways.
Certificate
• Draft Certificate is also reviewed by the Risk Assessment
Program as a QA/QC step before issuance
• After the Certificate is issued by DEQ, it must be signed by
the participant and landowner (also trustee, utility, etc., if
applicable) and recorded (if use restrictions) w/i 90 days.
• A certified copy of the Certificate as signed and recorded
must be submitted to DEQ
• Take away – Issuance of the Certificate by DEQ does not
occur “automatically” after the Demonstration of
Completion and Public Notice have been submitted. It is a
collaborative effort between the participant and DEQ. It is
a legal document, with fixed language, and a lot of details
that all must be accurate.
Questions?
Demonstration of Completion
Public Notice
Certification of Satisfactory Completion of
Remediation
What You Heard Today
• Tips for Characterization
– You know the site, we don’t. You
conclude, we concur
– Conceptual site model
– Several rounds of sampling
• Plume Stability
– Evaluate offsite risk
• Formatting
– Summary Tables
– Nice maps
– Full and complete responses
• State all assumptions
– Follow the format/terminology of
the Regulations
– Show your work
• It takes time! 2 years+
•First come, first serve
•Participation is Voluntary
•Tank Closure does not a certification
make
-TPH is of little value
•Meetings early in the process
•It’s all about the risk!
•Certificate language is fixed
•Uncertainty
•Survey questions
What Can DEQ Do Better?
Jeffery A. Steers. Director, Division of Land Protection and Revitalization
Durwood Willis, Director, Office of Remediation Programs
Wrap Up and Adjourn
Presented by:
Durwood Willis, Director, Office of remediation Programs