Challenge

A mid-Atlantic environmental firm contacted Carbonair to develop a groundwater remediation treatment system for a Brownfield development project. Three office complexes were being built in downtown Washington DC. Each building included underground parking, requiring excavation 65 feet below grade. Water samples revealed BTEX and TCE contamination, and hydrological testing indicated pumping rates of 1000 GPM would be necessary to allow construction to resume.

Solution

For this project, Carbonair designed a modular 1200 GPM treatment system consisting of twelve 100 GPM liquid phase carbon vessels on a common header. Each unit had a duplex bag filter skid and a Carbonair PC13 carbon absorber. Carbonair furnished the complete groundwater remediation treatment system, including hose, fittings, headers and valves. Carbonair’s field service team installed the system and trained the operating personnel.

Results

• This modular design allowed the water treatment system to continuously flow at 1200 gpm, while two liquid phase carbon vessels could be held in reserve and serviced if needed.
• Using a modular system with multiple small liquid phase carbon vessels resulted in less site preparation time prior to installation, when compared to larger carbon vessels.
• Due to extreme space restrictions, the carbon vessel system had to be moved several times during the course of the project. This was simplified by the compact, flexible design employed.
• After 14 months of operation, site conditions changed allowing for a reduction in the required flow rate. Carbonair was able to easily reduce the size and operating cost of the water treatment system, by simply removing several of the 100 gpm modules.