Tri-Service Site Characterization and Analysis Penetrometer System (SCAPS) Hydrosparge Volatile Organic Compound Sensor
Abstract
A July 1998 demonstration of the Hydrosparge volatile organic compound (VOC) sensor was conducted at the Naval Air Station (NAS) North Island, Coronado, CA. The purpose was to demonstrate the ability of the Hydrosparge VOC sensor to characterize the extent of groundwater contamination in a single field deployment and to evaluate the sensor with regard to the accuracy of analytical results, time required to characterize the extent of contamination, and the sensor's reliability and ruggedness. The Hydrosparge VOC sensor utilizes a commercially available direct push groundwater sampling tool to access groundwater. The in situ sparge module is then lowered directly into the groundwater and purges VOC analytes in situ from the groundwater with helium gas bubbles. The volatiles sparged from the water are carried via transfer tubing to a surface-deployed ion trap mass spectrometer (ITMS) where the contaminants are analyzed in real-time. The analysis is performed in accordance with U.S. EPA draft Method 8265 (U.S. EPA 1994) to a detection limit ranging from 1 to 5 ppb ( g/L). A total of 115 groundwater samples collected from 50 locations were necessary to characterize the extent of contamination at the NAS North Island, Building 379 site. Eight conventional groundwater monitoring wells were installed after the Hydrosparge demonstration and the analysis of water samples collected from these wells verified the extent of contamination. The Hydrosparge VOC sensor demonstration cost $158,173 for the collection and analysis of VOC samples and the completion of 16 cone penetrometer soundings that provide continuous soil lithology classification. A cost comparison between the actual costs of this demonstration and the estimated costs of completing a similar effort with monitoring wells showed that using the Hydrosparge VOC sensor potentially saved $75,000. This equates to approximately a 32 percent cost savings.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 2001
- Accession Number
- ADA607228
Entities
People
- George Robitaille
- Jed Costanza
- Karen F. Myers
- Marc Wise
- William T Davis