Various technologies for monitoring operation of an air contaminant mitigation system, such as a vapor intrusion and/or radon gas mitigation system, are disclosed. For example, in one embodiment, a monitoring system includes an air contaminant mitigation system to exhaust vapors from a contaminated area to a designated area and a sensor module coupled to the air contaminant mitigation system to generate sensor signals indicative of a sensor condition of the air contaminant mitigation system. The system may also include a sensor controller to receive the sensor signals from the sensor module and generate sensor data indicative of the sensor signals. Additionally, the system may include a data server to receive the sensor data from the sensor controller, store the sensor data in a local database, and transmit information based on the sensor data to a remote computing device.