Bay Area Rapid Transit Tunneling Beneficial Reuse Study

HT Harvey; California


Roux is actively engaged in a beneficial reuse project for Santa Clara Valley Transportation Authority (VTA). The VTA has been funded to create a 6-mile expansion to the Silicon Valley Bay Area Rapid Transit (BART) system. The expansion project will require a mechanical tunneling process that requires the addition of soil conditioner chemicals to the soil to excavate the soil to create a tunnel. A total of 3.5 million cubic yards of excavated material will be generated and the goal is to place the material into several former salt production ponds around South San Francisco Bay to raise the pond bottom for the purposes of accelerating the timeline for tidal marsh habitat restoration.

Roux services include development of a toxicity testing program to help the San Francisco Regional Water Quality Control Board and the San Francisco Bay Conservation and Development Commission to determine the effect of the conditioned soil (TBM spoils) on aquatic and benthic receptors if such material were placed in the ponds. The biological evaluation will effectively serve to integrate the chemical and biological interactions between the TBM spoils and ecological receptors dwelling in ponds and determine the viability of this proposed beneficial reuse plan.

Learn more about Public Sector and Ecological Risk Assessment Services.


San Francisco, California


HT Harvey

Roux Services

Sediment Toxicity Testing

Aquatic Toxicity Testing

Biological Evaluation

Ecological Risk Management Decision-Making

Salt Marsh Restoration

Beneficial Reuse