The purpose of a remedial investigation and feasibility study (RI/FS) is to investigate, collect, develop and evaluate the required information regarding a site to support the selection of a remedy that protects human health, public welfare and the environment. The scope of the RI/FS is site specific and will depend on the amount and quality of available information. As new information becomes available, the scope may be reevaluated and, if appropriate, modified. Remedial Investigations and Feasibility Studies conducted pursuant to the requirements of CERCLA at 40 C.F.R. 300 will be deemed to meet the requirements of this rule.
Initial planning of the RI process is required. Many of the initial planning steps are continued and refined in later phases of the RI. The plans in this rule shall be submitted to the Department by the responsible parties for review and approval prior to the implementation of the Site Characterization.
An initial survey shall be performed by the responsible parties of all Background contaminant levels and Applicable or Relevant and Appropriate Requirements (ARAR's) for the media of concern. ARAR requirements and Background requirements are detailed in paragraphs (3) and (4) of Rule 0400-15-01-.08 respectively.
The workplan is a written document that summarizes the decisions and evaluations made during the data gathering phase and presents proposed activities, assigned responsibilities, project's schedule, and cost. The RI workplan shall be implemented by the responsible parties as approved by the Department unless the Department approves modification of the plan. The workplan shall contain but not be limited to the following, or as determined by the Department:
A general explanation of the reasons for the RI and the expected results and goals of the RI process.
The current understanding of the physical setting of the site, the site history, and the existing information of the condition of the site shall be described.
The information developed is presented, describing the potential migration and exposure pathways, and assessment of human health and environmental impacts.
Data requirements for the risk assessment, alternatives identified, and the workplan approach is presented to illustrate how the activities will satisfy data needs.
The tasks to be performed during the RI are to be described. This description shall incorporate the RI site characterization tasks and the data evaluation methods to be used.
Before performing site activities a health and safety plan which complies with OSHA requirements shall be prepared and submitted by the responsible party(ies).
A sampling and analysis plan shall be prepared by the responsible party for sampling activities which are part of the investigation and remedial action. The level of detail required in the sampling and analysis plan may vary with the scope and purpose of the sampling activity. The Sampling and Analysis plan shall be implemented as approved by the Department, unless the Department approves modification of the plan. The sampling and analysis plan shall specify procedures which ensure that sample collection, handling, and analysis will result in data of sufficient quality to plan and evaluate remedial actions at the site. References to standard protocols or procedures manuals may be used provided that the information referenced is readily available to the Department. The sampling and analysis plan shall contain but not be limited to the following, or as otherwise determined by the Department:
A site characterization is an investigation conducted by the responsible party that identifies and documents the extent of contamination. Based on the findings of the Initial Investigation, the site characterization investigations shall focus on potentially contaminated media, potential routes of migration, and potential human health and environmental concerns. Such investigations will include as appropriate, the following:
Investigate the surface water and sediments to characterize significant hydrologic features such as surface drainage patterns and quantities; areas of erosion and sediment deposition; floodplains; and actual or potential hazardous substances migration routes toward and within these features. Sufficient surface water and sediment sampling shall be performed to adequately characterize the areal and vertical extent and concentrations of hazardous substances. Properties of surface and subsurface sediments which are likely to influence the type and rate of migration shall be identified.
Investigate the areal and vertical distribution and concentration of hazardous substances in the soil. Identify properties of surface and subsurface soils which are likely to influence the type and rate of hazardous substance migration. Determine if the site is underlain by bedrock and if so, determine the type of bedrock underlaying the area of contamination. Evaluate the potential for hazardous substance migration at the soil-bedrock contact and below the top of bedrock along bedding planes, joints, faults and solutionally enlarged features.
Investigate site geology and concentrations of hazardous substances in the groundwater, the physical and chemical characteristics of the hazardous substance, potential future uses of the ground water, the persistence and permanence of the contaminant. This shall include, but not be limited to, the description, physical properties and distribution of bedrock and unconsolidated materials; groundwater flow rate and gradient for affected and potentially affected aquifers; ground-water divides; areas of groundwater recharge and discharge; location of public and private production wells; and groundwater quality data. In karst terrains, the Department may require additional investigative techniques to determine groundwater flow and the extent of contamination. If site contamination is shown to be limited to the soils, a site specific decision will be made by the Department concerning ground water monitoring.
Evaluate air quality impacts, including sampling, and information regarding local and regional climatological characteristics which are likely to affect the hazardous substance migration.
Determine the impact or potential impact of the hazardous substance on the human population and land use, such as sensitive environments, plant and animal species, and number of people in the area.
Define the location, quantity, concentration, and areal and vertical extent of the hazardous substance at the site.
At anytime during the RI/FS, an interim action may be required.
The purpose of this rule is to describe how certain interim actions can occur prior to completion of a remedial action. An interim action is:
Public notice may be required on an interim action as directed by the Department.
Unless otherwise directed by the Department, a report shall be submitted prior to conducting an interim action. Reports shall be of a scope and detail commensurate with the work to be performed and site-specific characteristics, and shall include, as appropriate:
An evaluation of alternative cleanup actions that protect human health and the environment, by reducing or otherwise controlling risks posed through each exposure pathway and migration route, shall be conducted by the responsible party. The number and types of alternatives to be evaluated shall take into account the characteristics and complexity of the site. A phased approach for evaluation of alternatives may be required for certain sites, including an initial screening of alternatives to reduce the number of potential remedies for the final detailed evaluation. The final evaluation of cleanup action alternatives that pass the initial screening shall consider the following factors:
A report consistent with paragraphs (2) and (3) of this rule shall be prepared and submitted to the Department by the responsible party for review and approval at the completion of the RI/FS. Additionally, the Department may require reports to be submitted following discrete elements of the remedial investigation and feasibility study. The report shall systematically summarize all information gathered during the RI/FS phase and shall include all sampling data, tables, graphs, and other information requested by the Department.
Tenn. Comp. R. & Regs. 0400-15-01-.09
Authority: T.C.A. §§ 68-212-201 et seq. and 4-5-201 et seq.