Elizabeth Mine
Tailings Pile
Coulld Collapse

The massive tailings pile at the Elizabeth Mine in South Strafford is unstable and could collapse, sending a "catastrophic" flood wave down the valley, recent engineering findings have indicated.

The collapse could release up to a million cubic yards of tailings in a wave moving 7-10 miles an hour, according to engineering information. It could destroy as many as 11 homes, the report said.

However, those familiar with the mine site were less alarmist, noting that the pile has been there for 50 years and there is no sign of immediate trouble.

As the result of the new concerns, Sens. Jeffords and Leahy on Monday penned a joint letter to Christine Todd Whitman, administrator of the Environmental Protection Agency (EPA), seeking help for quick action to stabilize the tailings pile.

Later in the week, the New England office of the EPA issued a statement about the potential problem, as well as a notification to homeowners downstream of the tailings pile.

"The EPA takes this situation very seriously," said Robert W. Varney, administrator of EPA's New England office.

The prospect that the 40-acre tailings pile might collapse is startlingly new, despite the fact that the Elizabeth Mine has been under intense scrutiny for two years. Previously, the concerns centered on metallic pollution from the tailings pile that made its way into Copperas Brook and then the West Branch of the Ompompanoosuc River.

Because of the pollution, the EPA has declared the Elizabeth Mine to be a Superfund site, despite the fact that no danger to human health has been cited. The agency has spent $3.5 million in studies so far.

Some of those studies, in addition to findings by a local engineer who has donated hours of his time, have resulted in a new, more troubling, view of the tailings pile. According to the engineers, what appears to be a "pile" is actually constructed like a dam. Behind the dam—or in the pile—is a large amount of goopy material, described as slurry or saturated silt and clay.

Like a 'Pudding'

"It's more like a pudding, with a crust on top," explained John Freitag, the chairman of Citizens for a Sensible Solution, which has been studying the proposals for the mine.

The letter to Whitman—and the technical support information released at the same time—paints an alarming picture.

The site could collapse "under normal spring thaw conditions," the Senators' letter said. "The EPA has determined that such a flood wave would be catastrophic, destroying a number of homes and causing widespread environmental devastation,"

Collapse "could be generated by one week of spring run-off or a period of heavy rain," the technical information says.

Met with Selectboards

The EPA news release this week followed a meeting Monday night of the Selectboards of Strafford and Thetford to discuss the new engineering finding, at which Environmental Conservation Commissioner Jeff Wennberg was present.

Also at the Thetford meeting were Tom Barry from Sen. Jeffords's office, and other representatives from the state and the Army Corps of Engineers.

The EPA has enough money to stabilize the tailings pile temporarily, the report said. Pumps will be placed atop the pile to prevent water from building up.

In addition debris racks will be installed to keep the "decant system" from plugging up. This is a system of pipes that is supposed to drain water out of the pile. If the system were to plug up, water pressure could build up rapidly within the pile, engineers said.

The decant system is in "poor condition with cracks and partial blockage," the report said.

The two U.S. Senators asked Whitman to release additional money this summer so that more permanent steps can be taken. These would include new drains, and pipes or channels that would divert water from the top of the pile.

Collapse Possibilities

There are three ways the "dam" could collapse, the report said:

First, water collecting on top of the pile might overflow and wash out the dam;

Second, increasing water content and pressure within the dam could result in a landslide;

Third, seepage (called "piping") of fine materials could create sinkholes, which can collapse and damage the dam.

The engineer who first realized implications of the structure of the tailings pile was Dick McGaw of Norwich, who became independently interested in the Superfund site and did some work for Citizens for a Sensible Solution. McGaw worked with engineering drawings of the tailings pile and conferred with older citizens who remembered when it was created.

McGaw's suspicions were then confirmed by the EPA's chief engineer for the site, Chris Hatton, who works for a private company contracted with EPA.

Two Meetings

The EPA has scheduled two public meetings, set originally to talk about how the Superfund project would affect historic resources, i.e., the remnants of the old mine. They are at 5:30 p.m. April 9 at Barrett Hall in Strafford and on April 16 at the Parish Players Hall in Thetford.

At the same time the EPA is coordinating a response to the threat of dam collapse, it is still awaiting funding for a roughly $20 million clean-up of the site itself. EPA funds for this clean-up did not come through this year.

By M. D. Drysdale