Project highlights:

  • Vapor mitigation project for new fire station with oversight from county Department of Environmental Health
  • Nitra-Seal® installed to prevent vapor intrusion from volatile organic compounds, including benzene, bromodichloromethane, and chloroform

To meet growing emergency needs, a Northern California fire station was built on a former industrial site with contamination history. Listed on the Department of Toxic Substances (DTSC) Hazardous Waste site list due to a past UST leak, environmental tests found elevated concentrations of benzene, bromodichloromethane, and chloroform in soil gas, posing a vapor intrusion risk. To mitigate this, the city entered a Remedial Action Agreement with the county, which required a Vapor Intrusion Mitigation System (VIMS) to protect first responders. The environmental consultant designed a site-specific contaminant vapor barrier system using Nitra-Seal, which is applied beneath the foundation, creating a long-term barrier against vapor intrusion. The Nitra-Seal vapor barrier was installed by a Land Science certified installer and was completed in accordance with the required QA/QC procedures.