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

  • Hawaii Elementary School Reopens Following $25M Campus Modernization

    Haʻaheo Elementary School in Hilo, Hawaii, has reopened to students following a three-year, $25-million campus modernization and expansion project that significantly increases the school's instructional space while preserving one of the island's oldest educational institutions, according to local news.

  • University of Pennsylvania Releases Design of Future Physical Sciences Building

    The University of Pennsylvania (Penn) in Philadelphia, Penn., recently released renderings of an upcoming 350,000-square-foot Physical Sciences Building, according to news release. The facility was designed by CO Architects and will unite the university’s departments of Physics and Astronomy, Mathematics, and Earth and Environmental Science.

  • Construction Begins on 100+ Acre K–12 Campus Designed for Lakota Culture

    The Cheyenne River Sioux Tribe (CRST) and the Cheyenne-Eagle Butte School District in Eagle Butte, S.D., recently broke ground on a new K–12 campus that will cover more than 100 acres and serve students and families across 1,600 square miles, according to a news release.

  • UNH Marks Construction Milestone on Oceanic Exploration Facility

    The University of New Hampshire in Durham, N.H., recently celebrated a major construction milestone with a beam-signing ceremony for the new Center of Excellence for Operational Ocean and Great Lakes Mapping, according to a news release. The facility’s ultimate goal is to support research, training and technical assistance in ocean mapping.