Challenge

Extremely high levels of Methane and over 10,000ppm of H2S in the soil under downtown Los Angeles near the La Brea Tarpits was making the path for a large tunnel boring machine very difficult. To get through the worst sections they knew they were going to need a solution to keep the levels in a safe range to keep the crew and equipment underground safe and avoid costly evacuations and subsequent delays due to hazardous gasses.

Solution

Envent provided equipment over a three-year span ranging from small carbon vessels all the way up to our 42 MMBTU/H EMECS42 Thermal Oxidizer along with three other Smaller thermal oxidizers. All of these are working in parallel with recirculating scrubbers to process the high levels of H2S and destroy the methane.

Benefit

Alternative solutions were estimated to be 4-5 times as costly and had major safety concerns. The Envent solution left almost no long term underground infrastructure and required very little disturbance aboveground besides the traffic control for the work area.