Boswell Engineering was retained by the Port Authority to perform an environmental investigation of the two (2) Port Authority Trans-Hudson (PATH) tunnels connecting Exchange Place Station in Jersey City, New Jersey to the World Trade Center (WTC) in New York City, New York. The project was designed to investigate the tunnels for various contaminants including PCBs released from the WTC electrical transformers, petroleum hydrocarbons from the building’s ruptured underground storage tanks (USTs), pollutants that may have washed into the tunnels by both the fire fighting and dust suppression efforts at Ground Zero, and biological agents from mold and bacterial growth within the tunnels.
Boswell immediately developed a comprehensive Health and Safety Plan (HASP) to address potential site dangers such as the oxygen deficient atmosphere inside the tunnels and the release of hydrofluoric acid from the former buildings’ chilling units. In addition, Boswell devised a conceptual sampling plan, conducted initial site entry and tunnel scoping, prepared its sampling teams, gathered and packed the necessary equipment, and obtained authorization to access Ground Zero.
During the investigation, Boswell conducted initial air sampling and collected samples from various matrices along the entire 1-mile length of both PATH tunnels. On the first day of the investigation, Boswell entered the tunnels from the Jersey City side using Level B personnel protective equipment (PPE) and collected samples from Exchange Place to the tunnels’ approximate midpoint. Once the tunnels were deemed safe for entry, the Boswell team and Port Authority personnel proceeded using Level C PPE. On the second day of the investigation, Boswell sampling team entered the PATH tunnels from the WTC site through the North and South Projections and completed sampling from the tunnel entry points to their midpoints.
Additionally, Boswell developed and implemented a sampling plan that included the collection of grab samples from various matrices at 100’ intervals along the entire length of each tunnel. Specifically, samples were collected from the railroad ballast, the intermixed soil and sediment beneath the railroad ballast, and the material found within the tunnel drains. These samples were subsequently analyzed and used by the Port Authority for disposal characterization and for evaluating worker safety during the tunnels’ planned retrofit. Air samples were collected and analyzed for total bacteria and total mold. Using the bacterial analysis, spot decontamination was performed prior to worker entry and the tunnel’s eventual retrofit.