Construction Progress at the Former Hempstead Manufactured Gas Plant
Week Ending 09/26/2008

National Grid’s contractor (ENTACT Environmental Services) installed erosion and sedimentation control fabric along the construction site perimeter and stone in a vehicle parking area. All remaining interior fence was removed and disposed. Brush and debris from the site were consolidated and stockpiled prior to being loaded for off-site disposal. Electrical service was installed and connected to construction trailers, and power lines were installed for community air monitors.

Drilling and sampling activities continued on site to support the design of the soil solidification phase of the remedy for deeper tar impacted soil. Air monitoring is conducted during the work to ensure that the work does not produce airborne contaminant levels above regulatory standards. Alarms are triggered at levels significantly below regulatory standards to ensure corrective action can be taken before exceedance of regulatory standards occur.

Off-site drilling and sampling began on Smith Street to support the design of the groundwater treatment system. While drilling, each work area is surrounded with temporary orange fencing and air monitoring is conducted during the work to ensure that the work does not produce airborne contaminant levels above regulatory standards. As noted above, alarms are set significantly below regulatory standards.

Two-week outlook:  Drilling and sampling activities will continue on- and off-site. A concrete retaining wall located on-site will be demolished and disposed off-site. Trees and vegetation will be cleared from the northern part of the site to allow the construction of a temporary fabric enclosure for enclosing the contaminated soil excavation areas. Other trees will be relocated in conjunction with the work in this area. Community air monitoring station installations will be performed at the site perimeter.