Micro Ion Mobility Sensor (MIMS) for In Situ Monitoring of Contaminated Groundwater
ER-1603
Objective
Two-dimensional display (right) of chlorinated hydrocarbons (left) predicted with micro ion mobility sensor (center).
The Department of Defense (DoD) needs a reliable, lowcost, real-time sensor for monitoring groundwater contaminants at military sites. Contaminants of concern include chlorinated hydrocarbons, perchlorate, and explosives. Current analytical methods were developed for site characterization, which requires time-consuming sample preparation and laboratory analyses that are labor-intensive, slow, and expensive. The emergence of sensitive, robust, and fast-responding ion mobility spectrometry (IMS) technology provides the opportunity to develop an in-situ environmental monitoring instrument with the ability to detect chlorinated hydrocarbons in groundwater and soil vapors. Specific challenges include reducing interference in hostile environments, achieving high identification power, and effectively converting liquid sample to vapor phase.
The objective of this project is to develop a novel realtime sensor for providing cost-effective and reliable in situ monitoring of contaminated groundwater. The core technology involves combining linear and nonlinear ion mobility spectrometers in a miniature configuration and incorporating the vapor analyzer with an advanced membrane inlet. Monitoring chlorinated hydrocarbons in groundwater will be the initial focus, but the instrument also can be modified to detect explosives and perchlorate contaminants.
Technical Approach
A technology that is currently used at airport security checkpoints to rapidly screen for the presence of trace explosives and at battlefields to detect trace chemical warfare agents will be adapted for the specific purpose of long-term real-time monitoring of contaminated groundwater.
To achieve high reliability and low cost, three main tasks will be undertaken in this project: (1) convert contaminants from liquid phase into vapor phase using a novel membrane separation; (2) achieve sensitive identification of contaminants by combining linear and nonlinear IMS; and (3) reduce costs for long-term monitoring by making the sensor operation unattended and on-site, by adapting miniaturized structures, and by avoiding the use of vacuum equipment. An important milestone is two-dimensional separation of chlorinated hydrocarbons using linear and nonlinear IMS.
Benefits
Benefits of this project include reliable and inexpensive methods for in-situ, long-term monitoring of chlorinated hydrocarbons in groundwater with high analysis frequency. The cost for long-term monitoring at DoD sites will be reduced by eliminating expensive field sampling and laboratory analysis, such as Environmental Protection Agency Method 8260, which is based on a combination of gas chromatography and mass spectrometry. (Anticipated Project Completion - 2011)
Project Documents
Points of Contact
Principal Investigator
Dr. Jun Xu
Oak Ridge National Laboratory (ORNL)
Phone: 865-574-8955
Fax: 865-576-5235
Project Documents
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.