This NASA SBIR program would develop air-dropped wireless networked sensors using miniaturized chemical field effect transistors (ChemFET) for the detection and mapping of heavy metals in water for ecosystem monitoring. We would combine our advanced nanotechnology thin film deposition process - Electrostatic Self-Assembly (ESA) - and strained nanomembrane ChemFET technology to produce a wireless sensor network for in situ environmental monitoring. The nanomembrane structure combined with NanoSonic's patented self-assembly processing approach allow a unique way to tune sensitivity and selectivity. The wireless sensor system would be capable of sensing multiple heavy metal materials, improve upon conventional sampling methods in terms of cost, sensitivity, and selectivity, and benefit future environmental analysis programs. NanoSonic has demonstrated a prototype wireless chemFET sensor node for heavy metal detection.