Cleaner Air is Safer Air

cleaner air

Vapor Mitigation Strategies’ team completed the piping from the vapor pits to the risers for the SSDS, installed the AVB, and installed four vapor monitoring wells to ensure there was no vapor intrusion at D.C. early childhood centers, ensuring student safety.

A national chain of early childhood education centers chose the location of its Washington D.C. project on property known to have soil and groundwater contamination left behind from its former uses. The building designers were cognizant of the potential for vapor intrusion risk which might present itself to a sensitive population and researched design options.

Their choice was to employ a vapor intrusion mitigation system, which included a combination of two elements: an active pump sub-slab depressurization system (SSDS) component, and a spray-applied asphaltic vapor barrier (AVB). The SSDS consists of two square subterranean concrete vault “pits” with slotted openings at the top, and piping running from the pits to risers penetrating the sub-floor.

Both vapor pits were installed as part of the General Contractor’s (GC) pre-vapor intrusion mitigation installation commitment to provide for large scale construction items prior to the finishing of the SSDS and AVB by vapor intrusion mitigation installation specialists.

The GC accomplished pre-installation work which included construction of the vapor pits, all plumbing and electrical penetrating uprights, concrete collars around clustered penetrating uprights, smooth-grinding of rough surfaces for attachment of AVB to the foundation, and constructed and compacted the sub-slab gravel bed.

Vapor Mitigation Strategies’ team completed the piping from the vapor pits to the risers for the SSDS, installed the AVB, and installed four vapor monitoring wells.

The AVB was installed using a three-layer approach. First, by applying a polypropylene tarp which was rolled out tailored to fit around the vertical uprights and sealed to the foundation or uprights with Geo-Seal.

After the tarp was completely rolled out and all uprights and edges were addressed and sealed, the core layer of Geo-Seal was sprayed over the entire area.

Then, a final layer of tarp was installed to provide protection to the vapor barrier itself since metal rebar and concrete were layered on top.

www.vapormitigationstrategies.com

This article originally appeared in the School Planning & Management February 2018 issue of Spaces4Learning.

Featured

  • California K–12 District Completes Elementary School Campus Replacement

    The West Contra Costa Unified School District (WCCUSD) in Richmond, Calif., recently announced the completion of a replacement campus for Lake Elementary School, according to a news release. The school has capacity for 470 students between Transitional Kindergarten (TK) and sixth grade.

  • Photo credit - Chuck Coates

    Florida District Modernizes Central Energy Plants at Two High Schools

    Flagler Schools, a public school district in Flagler County, Fla., recently partnered with Matern Professional Engineering to modernize the central energy plants at two of its high schools, according to a news release. The project is part of a larger, district-wide effort to reduce energy costs and operational expenses.

  • UT System Approves First Funds for New Campus

    The University of Texas System Board of Regents recently approved funds to build the first facility of a new campus in far west Fort Worth, Texas, according to university news. UTA West will serve as a branch of the University of Texas at Arlington and is scheduled to open in fall 2028.

  • DFW-Area District Opens New Replacement Middle School

    The Eagle Mountain-Saginaw Independent School District near Fort Worth, Texas, recently held a ribbon-cutting ceremony for a new replacement middle school campus, according to a news release. The new facility for Wayside Middle School, originally established in 1964, was built on the site of the former district administration building and funded through Bond Proposition A in 2023.