Thermal NSZD: Continuous Remote Monitoring of Natural Source Zone Depletion (NSZD)
Thermal NSZD® is a continuous thermal monitoring system that is used to estimate the daily and cumulative mass of LNAPL destruction in the subsurface by microbial activity (Horst et al., 2017; Sale et al., 2018; Kulkarni et al., 2020). The conversion of net temperature change to mass degradation is based upon a series of thermodynamic equations developed by Colorado State University (US Patent No. 10,094,719). Thermal NSZD® measures the heat generated by biodegradation processes using a vertical series of thermocouples, which can then be converted to a biodegradation rate. Temperatures are corrected from a non-impacted background location to remove seasonal temperature effects in the subsurface.