Downhole Sensor for Long-Term Monitoring of Groundwater for Contamination by Explosives.

摘要

This report concludes and details the efforts expended during 2004 and 2005 by Nomadics under the bridging effort for SERDP Project CU-1298. The scope of the work performed involved miniaturizing the SERDP Project CU-1298 Phase I explosives sensor in order to deploy the sensor in a two-inch groundwater monitoring well without compromising the performance of the sensor, as well as adding data logging capability to the sensor. A prototype sensor capable of deployment in a two-inch groundwater monitoring well was constructed and tested extensively in the lab, and its performance is comparable to the previous laboratory prototype constructed under SERDP CU-1298 Phase I. Hence, the project objectives were successfully accomplished. The integration effort involved miniaturizing the flow cell, optics stack, PC board, and supporting hardware. A miniaturized prototype sensor was constructed, assembled, tested, and debugged. This prototype sensor was engineered using technology from two other Nomadics sensors, an underwater TNT sensor (SeaDog) and the Fido TNT vapor sensor (Fido). Both sensors employ patented Amplifying Fluorescing Polymer (AFP) technology. The vapor sensor is capable of detecting TNT at the parts-per-quadrillion level, and the aqueous phase sensor can detect TNT in water at low parts-per-billion levels. Both sensors have been tested extensively in the field. Several technologies have been borrowed from the Fido sensor and used in the prototype sensor including data logging capability. Data logging was implemented in order to record data while sampling, which will allow users to analyze the traces for TNT presence at a later time.