Styrene? Not in My Ambient Air! A DC Water Case Study for Air Quality Monitoring and Testing during CIPP Installation at Soapstone Valley Park

The District of Columbia Water and Sewer Authority (DC Water) is repairing 6,200 linear feet of clay sewers constructed more than a century ago. The project is in Soapstone Valley, part of Rock Creek Park. The sewer system will be rehabilitated using hot water curing and a styrene-free resin. In July 2021, DC Water proactively issued a Supplementary Standard Specification for CIPP adding requirements for air emissions. In June 2022, during the construction phase, local elected officials passed a resolution urging the Department of Energy and Environment (DOEE) to require DC Water to obtain an air quality permit for the CIPP work. DOEE required DC Water to submit an Air Quality Monitoring and Testing Plan (AQMP). A third-party contractor via the Water Research Foundation (WRF) will implement the Air Quality Monitoring Plan during CIPP installation. This study addresses worker safety, community safety, and the potential for air emissions during CIPP. According to the safety data sheets (SDS), the resin material contains no volatile organic compounds (VOCs). However, based on the review of the activator SDS, cumene and acetophenone are anticipated. Baseline samples will be collected. The research team will document the field conditions during air monitoring—daily activities, site maps, corrective actions taken, and unusual field situations, which may impact samples or sampling. An action level response plan was prepared, including clear protocols in the event concentrations in the ambient air, or lateral sewers exceed acceptable levels. Daily results will be reported to DOEE and shared with the community. The final report of air quality monitoring will be used to inform future construction approaches and data gathering efforts. Eventually, the project will generate data for DOEE to evaluate the effectiveness of monitoring and mitigation measures in the district. With the implementation of the AQMP, DC Water hopes to ensure the project is carried out in accordance with best practices aimed at mitigating environmental risks. Ultimately, the results of the study will provide broad value to utilities across the USA. This paper and presentation will focus on the regulatory framework that led to the AQMP and the air quality results.