For more information on Pump and Treat Optimization, please contact:
Kathleen YagerTechnology Integration and Information Branch
PH: (617) 918-8362 | Email: yager.kathleen@epa.gov
Remediation Optimization
Overview
What is a Remediation System Evaluation (RSE)?
The RSE process involves an independent team of experts that evaluates the performance of a remedy and makes recommendations to improve protectiveness, reduce costs, improve technical operation, and facilitate site closure. Other frequently asked questions and associated answers are as follows:
What comprises the independent team of experts?
EPA uses a team of two to four individuals with expertise in a variety of fields, including remedial engineering and hydrogeology. In addition, the team solicits advice from other experts, including chemists, geologists, cost estimators, regulatory experts, and others. The team has consisted of both private contractors and staff from the U.S. Army Corps of Engineers. The individuals were independent of the site and would not be affected by an increase or decrease in work resulting from implementing the recommendations.
What is the RSE process from start to finish and how long does it take?
The RSE process typically begins with an initial contact to transfer site information to the RSE team and to schedule a site visit. Prior to the site visit, the RSE team reviews the site documents and formulates questions that it will ask during the site visit. The site visit is generally 1 to 1.5 days in length depending on the complexity of the site. A draft RSE report is generally provided within 45 days of the site visit, though an expedited schedule can often be arranged.
Who is generally present at the site visit and what are the time commitments?
A site visit generally includes the RSE team, the site representative, the site contractor, and the site regulator. For the Fund-lead RSEs, the visit generally includes the RSE team, the EPA RPM, the site contractor, and the State project manager. The site representative should be prepared to discuss the site history, remedy status, and remediation goals. The site contractor should be prepared to answer specific technical engineering and hydrogeological questions. The time commitments for those involved is generally limited to gathering and distributing site information, planning and attending the site visit, and reviewing the RSE report.
What is the end result of an RSE?
An RSE report is generally 25 to 40 pages depending on the complexity of the site. The report provides site and remedy background information, a summary of the findings during the site visit, and recommendations to improve effectiveness, reduce cost, improve technical operations, and facilitate site closure. For each recommendation the potential costs and cost savings for implementing each of the recommendations are provided. A draft report is provided to the site representative for review and a final report is generated based on comments from the review.
What information is often provided to the RSE team?
It is helpful for the RSE team to review the following documents:
- remedial investigation report
- decision documents
- design reports and O&M manual
- recent O&M and monitoring reports (approximately 1 to 2 years worth)
- summary review reports (such as Five-Year Reviews)
- other pertinent reports that illustrate remedy performance
- annual O&M costs broken down into the following categories:
- project management, reporting, and technical support
- sampling labor
- operator labor
- utilities
- consumables and disposal costs
- laboratory analysis
- disposal
What types of questions does the team ask?
The following questions are examples of what might be asked at an RSE. The order that these questions are asked, the types of other questions that are asked, and the degree of follow-up questions vary by site.
- Please provide a history of the site that brings us to the present time. Please try to include any significant changes in the approach or strategy taken at the site, including modifications to previous decision documents. Please note that many aspects of this site history will provide discussion points.
- What is the conceptual model for the site? For example, what are/were the sources of contamination? Where are/were they located? What is the hydrogeological framework for groundwater flow and contaminant transport? What processes/mechanisms were involved in arriving at the currently observed conditions, considering both horizontal and vertical transport, contaminant degradation, recharge, groundwater extraction, etc? What are the potential receptors?
- Describe the extraction and treatment systems. What are the design parameters for the extraction wells, including contaminant concentrations and flow rates? What are the design parameters for the treatment system and each of its components, including design mass removal rate, design influent concentration, and design hydraulic capacity? What are the actual values of these parameters and how do they compare to the design parameters?
- What are the site objectives as specified in the ROD? Is the remedy achieving those objectives? If so, what monitoring is being done to confirm this? If not, what steps, if any, have been taken modify the remedy or the ROD?
- What are the discharge limits for the treatment plant? Which contaminants provide the most difficulty in meeting these limits? Are the discharge limits consistently exceeded?
- Please describe the current exit strategy for terminating some or all of the P&T system? How has this strategy changed over time? What elements of the remedy have led to these changes?
- What is the current procedure for analysis of aquifer and process monitoring data? Does this involve analysis of plume capture, changes in the plume area or extent, or other indicators of effectiveness? Does this include criteria for reducing monitoring locations or frequency over time?
- What is the current schedule for turning the site over to the State? What are the concerns, if any, of the State?
- If not provided prior to the RSE site visit, please break down the annual O&M costs into the following categories:
- project management, reporting, and technical support
- sampling labor
- operator labor
- utilities
- consumables and disposal costs
- laboratory analysis
- disposal
- What previous optimization efforts have been conducted? When were they conducted? What were the recommendations? What is the status of implementing those recommendations?
What types of sites would benefit from an RSE?
All sites that have not been recently evaluated by an independent team would benefit from an RSE. However, it may be more cost-effective for some of the simpler sites to receive a reduced-effort RSE that might include a smaller RSE team and a shorter RSE report.
How much does an RSE cost?
An RSE, as described above, costs approximately $25,000 on average. Actual costs depend on the site complexity and the level of effort requested by the customer. Reduced effort RSEs might cost approximately $10,000, and RSEs for more complex sites might cost over $30,000.
Where can I learn more about RSEs?
Please refer to the U.S. Army Corps of Engineers RSE checklists
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