mcp public hearing draft waste site cleanup advisory committee meeting march 28, 2013 1
TRANSCRIPT
MCP Public Hearing Draft
Waste Site Cleanup Advisory Committee Meeting
March 28, 2013
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Overview – Public Comment Process
• Public Hearing Draft is available for review, along with supporting documents at http://www.mass.gov/dep/service/regulations/newregs.htm#proposed
• Public Comments Due COB Friday, May 17, 2013
• 4 Public Hearings to hear/receive testimony (CERO 4/3 at 5pm; Boston 4/4 at 9:30 am; SERO 4/9 at 9:30 am; WERO 4/10 at 9:30 am)
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• Today’s WSCAC Meeting, focused on topics we haven’t covered recently
- NAPL/LNAPL,- Source Elimination/Control- Active Pathway Elimination System Requirements
• MCP Standard Amendments Info Session, April 5th, 10 am MassDEP Boston, 2nd Floor, Rooms A & B• Next Month’s WSCAC Meeting, April 25th
• LSP Association Meeting, Tues April 9th
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Other Outreach
• Consider proposals with your current and past sites in mind – Does it raise any unforeseen issues that should be
addressed/clarified?– Does it make sense/help/hurt – be specific– Provide site examples
• Provide specific language for revisions and explain why it is better/issue you are trying to address
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Written Comments -What’s Very Useful to MassDEP...
Non-Aqueous Phase Liquids (LNAPL/DNAPL)
and
Source Elimination/Control
310 CMR 40.0996:
“The presence of non-aqueous phase liquids (NAPL) having a thickness equal to or greater than ½ inch in any environmental medium is considered to be a level which exceeds Upper Concentration Limits (UCLs)” and hence which prohibits the attainment of a Permanent Solution.
310 CMR 40.0006:
This thickness is “as a continuous separate phase as measured in a groundwater monitoring well or otherwise observed in the environment.”
Multi-Phase Fluid Flow in Porous Media or LNAPL Conceptual Site
Model (LCSM)
Fundamental
More accurate
Not necessarily simple
• Keep it simple
• Focus on MCP and PS
• Clear, established, peer-reviewed, published works
Guiding Principles
MCP Changes Being Proposed• Eliminate ½ inch UCL• Correct NAPL definition (eliminate “continuous”)• Define “Stable” and “Non-stable” NAPL• Reference LCSM principles (site characterization
and remediation “to the extent feasible”)Revised Source Elimination/Control Provisions
addressing range of source issues, including NAPL and limiting exposure potential (e.g., vapor intrusion)
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Proposed Definitions 40.0006Conceptual Site Model or CSM means a site-specific description of
how contaminants entered the environment, how contaminants have been and may be transported within the environment, and routes of exposure to human and environmental receptors that provides a dynamic framework for assessing site characteristics and risk, identifying and addressing data gaps and managing uncertainty, eliminating or controlling contaminant sources, developing and conducting response action strategies, and determining whether those strategies have been effective in achieving desired endpoints.
LNAPL Conceptual Site Model and LCSM each means a Conceptual Site Model which includes the body of fundamental scientific principles describing the behavior of fluid flow in porous media necessary to assess LNAPL in subsurface strata. (See also Conceptual Site Model). 11
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Proposed Definitions (cont.)
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Residual LNAPL Saturation means the range of LNAPL saturations greater than zero up to the LNAPL saturation at which LNAPL capillary pressure equals pore entry pressure. It includes the maximum LNAPL saturation below which LNAPL is discontinuous and immobile under the applied gradient.
Transmissivity and Tn each means the rate at which a liquid of the prevailing kinematic viscosity is transmitted through a unit width of the formation under a unit hydraulic gradient. It is equal to an integration of the hydraulic conductivities across the saturated part of the formation perpendicular to the flow paths.
Proposed Definitions (cont.)
Proposed Language - Notification
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Proposed Language - Phase I Assessment
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Proposed Language - Phase II Assessment
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Proposed - Phase II Assessment cont.
Proposed LanguageRisk Characterization – Method 3 UCL
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Proposed Language -AULs
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Source Elimination/Control
• Provide basic definition of “Source of OHM Contamination” that refers to the original OHM release location and/or contaminated media from which OHM can migrate as a bulk material.
• Source of OHM Contamination shall be eliminated, if feasible.
• If elimination is not feasible, then Source must be controlled; performance standards for “Source Control” are specified.
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Intent -
Source Control Performance Stds.
• Absence of Non-Stable NAPL• Removal of LNAPL to extent feasible
(using LCSM principles)• OHM plumes in any media not expandingAbsence of DNAPL constituent
concentrations greater than 1% of their solubility limit
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Proposed Definition - Source of OHM Contamination 40.0006
Source of OHM Contamination means a point of discharge of OHM into environmental media and/or OHM within environmental media, that is migrating or is likely to migrate in a dissolved or vapor state or as a separate phase liquid. Sources of OHM Contamination may include, without limitation:
1. leaking storage tanks, vessels, drums and other containers;2. dry wells or wastewater disposal systems that are not in compliance with regulations governing discharges from those systems;3. contaminated fill, soil and sediment;4. sludges and waste deposits; and5. Nonaqueous Phase Liquids.
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Proposed LanguageSource Elimination/Control
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Source Elimination/Control (cont.)
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(c) Parties conducting response actions shall seek to eliminate each Source of OHM Contamination. In cases where such elimination is not feasible, response actions shall control each Source of OHM Contamination. For the purposes of 310 CMR 40.1003(5), control of each Source of OHM Contamination requires:
1. the absence of unpermitted releases of OHM to the environment;2. the absence of any Non-Stable NAPL; 3. the removal of any LNAPL to the extent feasible, based upon cost-benefit analysis using current LCSM principles which may include, but are not limited to, Transmissivity, Residual Saturation, and/or decline-curve analysis;4. the absence of any DNAPL constituent concentration greater than 1 percent of its solubility limit; and5. demonstration that OHM plumes in any environmental media are not expanding.
(d) The feasibility of eliminating or controlling a Source of OHM Contamination shall be evaluated in accordance with the criteria in 310 CMR 40.0860.
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(c) ... control of each Source of OHM Contamination requires:
1. the absence of unpermitted releases of OHM to the environment;2. the absence of any Non-Stable NAPL; 3. the removal of any LNAPL to the extent feasible, based upon cost-benefit analysis using current LCSM principles which may include, but are not limited to, Transmissivity, Residual Saturation, and/or decline-curve analysis;4. the absence of any DNAPL constituent concentration greater than 1 percent of its solubility limit; and5. demonstration that OHM plumes in any environmental media are not expanding.
LNAPL WorkgroupKen Marra, [email protected]