Wilcox is continuously developing and exploring sampling equipment and methodologies that increase data quality and reduce client expenses. The Wilcox Vapor Intrusion Practice Group recently began successfully utilizing specialized sub-slab soil gas sampling ports equipped with silicone seals.
These new ports exhibit several advantages over the traditional ports:
- Traditional sub-slab ports are comprised of multiple components that are combined to form a complete assembly, which requires time and effort and opens the door for potential error. The new ports are fabricated from a single piece of stainless steel.
- Traditional ports are installed into drilled holes and anchored in-place by applying cement mortar, and allowed at least 24 hours for curing to create a vapor resistant seal. The installation holes for the new ports are precisely drilled with guide bushings and sealed via an impermeable silicon sleeve. Specialty tooling ensures the ports and sleeves are installed correctly, and the ports are immediately available for sub-slab sampling with no curing time required. Recent experience with the ports at several locations has proven the installation process to be significantly more efficient and reliable.
- After installing any port, the integrity of the seal has to be evaluated, which is typically performed utilizing a tracer gas (usually helium) leak test. In the case of traditional mortar-sealed ports, this test cannot be performed for at least 24 hours following the installation, which requires re-mobilizing staff to the site. Failure of leak testing at traditional ports requires re-installation, an additional 24-hour delay before retesting, and additional rental costs for tracer gas testing equipment. With the new silicone-sealed ports, leak testing can be performed immediately following installation. Re-installation/re-testing can be performed immediately as necessary, thus saving significant time and expense. To date, Wilcox has not experienced any seal failures when using the new ports.