Use Of Mass-Flux Measurement and Vapor-Phase Tomography to Quantify Vadose-Zone Source Strength and Distribution
ER-201125
Objective
The overall objective of this project is to demonstrate that the vapor-phase mass discharge test and vapor-phase tomography can effectively characterize persistent contaminant sources in the vadose zone and measure their associated mass discharge. This technology can improve evaluation of vadose-zone source impacts on groundwater and vapor intrusion. The specific technical objectives for this demonstration are as follows: (1) demonstrate the vapor-phase mass discharge test as an effective means to quantitatively measure contaminant mass discharge in the vadose zone; (2) demonstrate vapor-phase tomography as a means of characterizing the 3D distribution of persistent contaminant sources in the vadose zone; (3) integrate the mass-discharge and vapor-phase tomography measurements with existing pneumatic and tracer tomography methods to provide a comprehensive technology to evaluate the impact of persistent vadose-zone sources on groundwater and vapor intrusion; (4) determine cost-performance factors for applying the technology as a function of site conditions, and compare them to costs associated with standard practices; and (5) develop decision-support tools to assist users in selection and application of the technology.
Technology Description
The vadose-zone characterization technology to be demonstrated is a combination of two recently developed methods (vapor-phase mass discharge test and vapor-phase tomography) and two existing methods (pneumatic tomography and tracer tomography). The technology improves on existing vadose-zone characterization methods by providing three key sets of information for vadose-zone contaminant sources:
1. Accurate measurements of vapor-phase contaminant mass discharge
2. Characterization of mass-transfer conditions (e.g., whether or not mass transfer is rate limited, and to what degree)
3. Higher resolution characterization of source distribution and source-zone architecture.
The technology is designed to be used in a tiered approach that is sensitive to associated cost-benefits and responsive to specific requirements of the site.
Benefits
It is anticipated that the vadose-zone characterization technology will produce information that will greatly improve the assessment of vadose-zone source impacts on groundwater and vapor intrusion. Specific applications for this information include decisions regarding implementation of vadose-zone remediation efforts, setting of remediation goals, optimization of remediation systems, and assessment of remediation system transition or closure. The technology will be especially useful for enhancing the performance of soil vapor extraction (SVE) systems and for supporting closure assessment for SVE systems. (Anticipated Project Completion - 2014)
Points of Contact
Principal Investigator
Dr. Mark Brusseau
University of Arizona
Phone: 602-621-3244
Fax: 602-621-1647
Document Types
- Fact Sheet - Brief project summary with links to related documents and points of contact.
- Final Report - Comprehensive report for every completed SERDP and ESTCP project that contains all technical results.
- Cost & Performance Report - Overview of ESTCP demonstration activities, results, and conclusions, standardized to facilitate implementation decisions.
- Technical Report - Additional interim reports, laboratory reports, demonstration reports, and technology survey reports.
- Guidance - Instructional information on technical topics such as protocols and user’s guides.
- Workshop Report - Summary of workshop discussion and findings.
- Multimedia - On demand videos, animations, and webcasts highlighting featured initiatives or technologies.
- Model/Software - Computer programs and applications available for download.
- Database - Digitally organized collection of data available to search and access.