Vapor Intrusion Mitigation System – Fontana, CA

Terra-Petra has been chosen to provide environmental engineering services for the design of the vapor intrusion mitigation system (VIMS) design for a new logistics center in Fontana, CA.

Over the last couple of years, we have seen an increased demand for vapor intrusion mitigation systems to be designed and installed at large commercial warehouse type buildings. The main driving force appears to be the environmental personality of the property in which the buildings are being constructed. The site history will vary, but a history of industrial or commercial use where the site was subject to a chemical release of some sorts is the commonality.

Whether it be a petroleum hydrocarbon (TPH) impact from a former oil field/oil well or a Volatile Organic Compound (VOC) release from a dry cleaner or manufacturing facility the potential impacts on the health and safety of the future occupants of the building is what needs to be addressed.

Terra-Petra is well equipped at designing these systems for the current conditions, as well as building in contingency design features for potential future changes. Essentially, we design passive venting systems that are easily upgradable to active subslab depressurization systems (with remote telemetry and remote system monitoring and maintenance built into it if such a conversion is warranted in the future).

The proposed development in Fontana will consist of the construction of a new warehouse building having an approximate 260,650 SF footprint. The vapor mitigation measures will specifically include a “passive” vapor barrier beneath the office areas of the planned warehouse building, and the installation of  a passive ventilation layer beneath the vapor barrier. Inclusion of a ventilation layer beneath the vapor barrier would enable it to be made “active” at a later date by adding in-line fans, such as those used for radon mitigation, to the vertical riser pipes inside the warehouse.

Radon Mitigation System – Summit County, CO

Terra- Petra is pleased to partner with a major property developer in Colorado to provide environmental engineering services for the design of a radon mitigation system for their development in Summit County, CO.

The project will consist of the construction of one single family home, and five  attached single family residences all with 3 stories and no basement. The homes are all nearly identical, with an approximate footprint of 2,500 SF. The project requires that a radon mitigation system be “roughed in” for future activation if needed, but our client is requesting that Terra-Petra design radon mitigation systems for each of the proposed buildings.

Terra-Petra has recommended that we design a combination passive venting and sub-slab membrane Radon Mitigation System for the proposed development.

Vapor Intrusion Mitigation Design – Hayward, CA

Terra- Petra is pleased to continue partnering with a major property developer to provide Vapor Intrusion Mitigation System (VIMS) Design Assistance in Hayward, CA. The scope of work involves mitigation of VOCs that could pose a potential vapor intrusion concern into a future occupied structure at the site.

This includes document review, conducting a Human Health Risk Assessment (HHRA) and submission of a Basis of Design report complete with Construction Quality Control procedures and an Operation, Maintenance and Monitoring plan (OM&M).

The vapor intrusion mitigation system will be designed in accordance with the Alameda County Department of Environmental Health’s Local Oversight Program (ACDEH) and in general accordance with the Vapor Intrusion Mitigation Advisory published by the C.A. EPA Department of Toxic Substances Control (DTSC) dated October 2011 (Cal/EPA 2011a, 2011b).

Vapor Intrusion Mitigation System Design – Pomona, CA

Terra Petra is currently working with a client to provide full scope vapor intrusion mitigation system design (VIMS), inspection, and monitoring services for their development in Pomona, CA.

The proposed development will consist of two new slab on grade, 3-story multi-family affordable apartment buildings with a combined footprint of 26,330 SF.

Terra-Petra will work with the City of Pomona (permitting agency) and with The Los Angeles County Department of Public Works (LACoDPW), Environmental Programs Division (EPD) which prescribes means and methods of protecting structures from vapor intrusion.

Vapor Intrusion Mitigation System – Palo Alto, CA

Terra-Petra’s Environmental Engineering Division has partnered with a significant environmental consulting firm in the Bay Area to prepare a comprehensive Vapor Intrusion Mitigation System (VIMS) for a new development located in Palo Alto, CA.

Terra-Petra designed the passive mitigation system with the ability to convert it to an active system in the future if deemed necessary. The VIMS System was reviewed and approved by the Department of Toxic Substances Control (DTSC).

Having completed the VIMS design we have moved on to the construction administration phase which includes submittal review and RFI responses, as well as the QA/QC inspections. We are currently on-site overseeing the smoke testing of the subslab membrane system.

For more on this project visit the City of Palo Alto Website