Twelve Mile River Project

From 1955 to 1977, the Sangamo-Weston capacitor manufacturing plant in Pickens dumped over 400,000 pounds of polychlorinated biphenyls (PCBs) into Town Creek, a tributary to Twelve Mile River, which flows into Lake Hartwell. PCBs are toxic manmade compounds that are very slow to break down, do not mix well with water, and settle into sediments where they can enter the food chain and accumulate in small organisms, fish and people. The U.S. Environmental Protection Agency has determined that PCBs are a “probable human carcinogen” and have numerous adverse effects, including physiological, immunological, developmental and reproductive.

Partial or total removal of the third dam would open up more than 100 miles of the river system to be free flowing, benefiting fish, water quality, and recreational users credit: Larry Dyck

As the result of Sangamo-Weston’s operations, there is now PCB contamination not only in Twelve Mile River but also in the upper Seneca River and Twelve Mile River arms of Lake Hartwell. These regions of the lake have had the most restrictive warning, “Don’t eat any of the fish,” for over 30 years.

In May 2006, Schlumberger, Inc. (the successor to Sangamo-Weston) signed a Consent Decree entered by the U.S. District Court in South Carolina that, among other things, requires Schlumberger to pay almost $12 million into a “restoration account” as compensation for damages to the natural resources of the river and Lake Hartwell. Most of this payment (nearly $9 million) is assigned to South Carolina, with the rest for Georgia. In addition, Schlumberger is required to dredge, and dispose of off-site, most of the PCB-contaminated sediments behind two of the three dams on the river (known as the Woodside I and II dams) and to dismantle the two dams. Schlumberger made the payment, but for over three years it did little to comply with the Consent Decree.

In July 2009, U.S. District Judge G. Ross Anderson, Jr. held a hearing on the lack of progress in implementing the decree. Upstate Forever, the Lake Hartwell Association, and the Pickens Soil and Water Conservation District were allowed to participate in the hearing.  Judge Anderson ruled that no further delay would be tolerated and ordered Schlumberger, Inc. to begin work immediately to remove the contaminated sediments and the Woodside I and II dams. Under Judge Anderson’s watchful eye, the project was back on track.

Locations of the three dams on Twelve Mile River in Pickens County; Woodside I and II Dams are being removed under court order

After the July hearing, we turned our attention to removing the third and final dam on Twelve Mile River. This dam is owned and used by the Easley-Central Water District for its water supply and is located upstream of the Woodside I and II dams. The Water District had no objection to removing the dam if an alternate water supply system were provided. The Pickens County legislative delegation, Pickens County Council, Upstate Forever, the Lake Hartwell Association, and the Pickens Soil and Water Conservation District expressed strong support for removing the third dam and providing an alternative water supply system as the top priority project for the restoration account.

Removing the third dam would achieve a wide range of public benefits, including restoration of natural river flows; movement of clean sediments from the river into Lake Hartwell, which is, in our view, the only way to achieve the goal of effectively capping the contaminated lake sediments; opening more than 100 miles of the river system and allowing unimpeded passage for many species of fish; improving water quality; and establishing outstanding whitewater paddling opportunities throughout the spectacular Twelve Mile River gorge.

Upstate Forever and other local groups have strongly advocated for the removal of the third dam on Twelve Mile River as a priority project for restoration account funds credit: Larry Dyck

Judge Anderson held a separate hearing on October 13, 2009 on the issue of how the almost $9 million allocated to South Carolina should be spent.  The hearing lasted five hours and included compelling testimony from Dr. Larry Dyck, a retired Clemson professor of biological sciences and Upstate Forever’s Clean Water Champion of the Year.

On October 27, Judge Anderson issued an order strongly recommending that $3 million of the funds be used toward the third dam project.  In addition, an online survey sponsored by the S.C. Department of Natural Resources showed that removal of the third dam is the project with the greatest level of public support. However, the Natural Resource Trustees, representatives of state and federal agencies responsible for distributing the restoration account funds, expressed concerns about the total cost and design of the project.

To address these concerns, groups advocating for removal of the third dam, including Upstate Forever, presented to the Natural Resource Trustees on February 11, 2010 a cost-saving proposal to remove a section of the dam rather than take out the entire structure. An earthen dam would be built perpendicular to the remaining section, and an open-channel flume would divert water from upstream into this new impoundment on the eastern side of the river. The western side of the river would become free-flowing, with associated habitat and water quality benefits. Plan sponsors requested $300,000 to study the feasibility of this project. 

In September, the Natural Resource Trustees approved funding the study, and work began in January, 2011 by Upstate Forever’s contractor to determine the extent of PCB contamination in the sediment behind the third dam.   After reviewing the results, the Natural Resource Trustees will decide whether to approve removing the third dam and providing an alternate system for the water district.  The Natural Resource Trustees released their plan in December, 2010 for distribution of the settlement funds.  Regrettably, only $2.1 million in the restoration account was reserved for the possible dismantling of the third dam, which is estimated to cost $4.5 million.  Hopefully, the Natural Resource Trustees will reconsider that allocation after the study is completed.

Meanwhile, the dredging of sediments behind the first two dams, Woodside I and II, finally began in late 2010. The dismantling of the Woodside I dam commenced on February 21, 2011, with the Woodside II dam removal following over the summer.  Upstate Forever and our partners raised concerns to the Natural Resource Trustees that Schlumberger did not remove nearly enough sediment from the river and that massive amounts of sediment (likely contaminated with PCBs) would wash downstream after the dams are removed. 

Upstate Forever paid for the collection and analysis of ten samples of the floodplain above the Woodside I dam in February 2011 to determine whether PCB contamination exists. The results show that five of the ten samples have levels of PCBs ranging from 9,670 to 54,000 parts per billion, far above the action level of 1,000 parts per billion. In fact, the 54,000 sampling result is the highest level of PCB contamination ever recorded above the Woodside II dam.

The samples were taken before the Woodside II dam was removed and just as our experts predicted, after removal of this dam and as the river began to reestablish itself, much of this unnatural floodplain sloughed off into the channel. In fact, the portion of the floodplain where the samples were taken no longer exists. The sediment and the PCBs have been mobilized and have moved downstream.

Discolored sediments, likely contaminated by PCBs, on the banks of Twelve Mile River credit: Larry Dyck

There is every reason to believe that other floodplain sediments above the Woodside II dam contained excessive levels of PCBs.  Schlumberger completed its limited dredging operation and removed the Woodside II dam in August 2011, so it is highly likely that massive amounts of PCB-contaminated sediments are moving downstream and settling out in Lake Hartwell. Instead of clean sediments covering the contaminated ones already in the lake, which is the basic goal of the remedy selected by the U.S. Environmental Protection Agency (EPA), more layers of contaminated sediments are being deposited in the lake.

We continue to monitor the progress of this project.

Portions of this article appeared in an op-ed piece by Brad Wyche, Upstate Forever Executive Director, and Dr. Larry Dyck, retired Professor of Biological Sciences at Clemson University, in The Greenville News, October 7, 2009.

Additional Information & Resources

• Go With the Flow: Removing Old Dams Benefits America's Rivers Economically and Ecologically
  Features the Twelve Mile Restoration
  The Economist, October 1, 2011