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National Grid asks for reconsideration on 100 percent coal tar removal


February 09, 2011
In response to the New Hampshire Department of Environmental Services preliminary decision to excavate full coal tar removal at the Liberty Hill site in Gilford, National Grid has requested that DES forego its 100 percent removal remedy.

Instead, Investigation and Remediation manager for National Grid Michele Leone suggested in a letter dated Jan. 28, the last day for public comment, that DES reconsider its current preliminary decision, focused on a full removal remedy.

Leone suggested that DES instead reverse its decision and fall back on a final decision made in Feb. 29, 2008, which focused on a lesser excavation remedy, leaving a percentage of contained, contaminated soil behind.

Leone stated that based on technical analysis, "There is no regulatory justification for the department's October 2010 decision to reverse its preliminary decision and select RAA1 as the remedy, and abandon its Feb. 29. 2008 selection of RAA5 as the remedy."

Remedy RAA1 stands for full excavation and 100 percent removal of toxic coal tar, while remedy RAA5 represents 80 percent removal of contaminant mass, including the installation of a cap, similar to the more recent remedy proposed by National Grid, RAA5a.

Leone argued that since the initial decision, nothing significant or substantive has changed from a technical or environmental standpoint that would justify DES's most recent preliminary decision and selection of remedy RAA1 made on October 2010. He described this decision to be "arbitrary and capricious."

He suggested that DES has acknowledged that full coal tar cleanup removal would be more expensive and would not cut the risk of human health or the environment any more so than an 80 percent plan.

Plan RAA1 is estimated to cost $16 million, while RAA5a is estimated to cost up to $10.9 million.

In the letter, Leone stated that this change in a preliminary decision is "inconsistent" with DES's decisions made in similar cases.

"The department has consistently interpreted its regulations to allow for the containment of contamination rather than requiring full removal at several similar sites in the State. The same interpretation should be applied here," said Leone. "Many more cases exist where the department has approved a remedy involving long term management requirements of contaminated soils left in place."

In October, 2010, DES had reported that RAA5a, a stem off of RAA5 with the addition of a groundwater pumping system designed by hired GEI Consultants, would in fact not meet all criteria for two main reasons: the remedy would not minimize long term management requirements, and the remedy would not minimize the potential need to modify the remedy over the longer term.

"The crucial point here is that nothing substantive changed from RAA5 to RAA5a that would justify the department's shift from RAA5 to RAA1 as the selected remedy," said Leone. "Both RAA5 and RAA5a are fully protective of human health and the environment, and comply with department regulations."

In his letter, Leone spelled out what he believed to be DES's proper regulations, which allow for a containment remedy verse full removal. He stated that DES's regulations provide that "contaminated soils will be removed, treated, or contained to reduce the human health risk associated with direct exposure."

Leone said that both proposed 80 percent remedies would abide by the above regulations and would remove and contain remaining contamination with the use of a slurry wall and cap, along with a groundwater pumping system.

As of the end of the public comment period on Jan. 28, DES will have 60 days to finalize or change its preliminary decision for 100 percent removal.

Canadian company Algonquin Power & Utilities Corporation recently purchased National Grid's New Hampshire business and will be responsible for the coal tar cleanup on Liberty Hill.

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