Health and safety is a critical part of the Lower Liberty Hill project as we work to investigate and address the environmental impacts at the site and improve the environment. National Grid is committed to protecting the public, our workers and contractors, and the environment from potential hazards that can occur as part of investigation and cleanup activities at the site.

Health and safety programs consist of careful planning, good communication and effective monitoring of environmental conditions at the site.  Investigation and remediation work at the site is performed by qualified contractors that are appropriately trained and monitored, and is performed in accordance with applicable regulations. Health and Safety Plans have been and will continue to be developed for each investigation and remediation activity at the site. Contractors are required to provide documentation of employee training and medical monitoring, and are evaluated based on their compliance with established health and safety plans.

During site remediation activities, public safety will be protected by establishing a Community Air Monitoring Program and a Traffic Control Program. The Community Air Monitoring Program will include air monitoring within the work zone and between the work zone and residential areas. Remediation of MGP wastes often results in strong odors that are sometimes unpleasant. Odors will be controlled to the extent practicable by limiting the size of the open excavations; using foam to cover exposed waste materials and by stopping work, if necessary, until wind and weather conditions improve. The Community Air Monitoring Plan will specify monitoring locations and air measurements that will indicate when additional odor or emission controls must be used and when the work must stop to protect workers and the public.

The Traffic Control Program will describe how we will manage traffic in and around the work area and how we will schedule truck traffic to and from the site. This program will include route planning for trucks and other vehicles, and coordination with local authorities and agencies on transportation safety issues.

Frequently Asked Questions

What is the problem?

Soil and groundwater has been impacted by the disposal of wastes from MGP operations in a gravel pit on Lower Liberty Hill Road in the early 1950’s. Some of the materials released are harmful to human health or the environment. The site remediation program will be designed to clean up the site so that it can be returned to valuable use in the community.

Should I be concerned?

The Site Investigation Report (GEI, 2006) accepted by the New Hampshire Department of Environmental Services showed that harmful materials are limited to the site and immediate vicinity. There are no current significant pathways through which neighbors or passersby could be exposed to the harmful materials located below the ground surface. Tests of the drinking water wells on the properties on which the wastes were found showed no impacts, and continued monitoring of drinking water wells in the area also show no impacts.

What can I expect when remediation starts?

The most visible activity will be the site excavation activities and the construction of the below ground containment wall, which will also be used to support the open excavation. Excavation activities will be performed by experienced construction crews using earthmoving equipment. The contaminated soil will be placed in trucks, covered with an odor-reducing foam if necessary, and covered with tarps prior to transporting the soil to the treatment facility. The trucks will be cleaned before leaving the site so that soil is not tracked onto the public roadway.   During the remediation, odors will be controlled to the extent practicable by limiting the size of the exposed excavation, using foam to cover exposed waste materials, and by stopping work, if necessary, until wind and weather conditions improve.