TERRY CREEK
Hercules removed approximately 85 percent of the toxaphene from the Terry Creek outfall ditch and portions of Dupree and Terry Creeks in 1999 and 2000. EPA’s selected 2017 builds on this work by capping the outfall ditch and rerouting the flow. The remedy effectively isolated residual toxaphene remaining in the outfall ditch so that it does not present a potential risk to the environment or human health.
Catching fish in Terry Creek for testing.
EPA selected the interim remedy in 2017 after extensive studies were conducted under the federal Superfund process, and with the concurrence of EPD. The plan can be found on EPA’s website. Implementation of the remedy involved capping and filling the former outfall channel while redirecting stormwater flow to a newly-constructed, state-of-the-art stormwater channel to the south.
Since fish caught in Terry Creek waters were tested in 1997, the quality of fish tissue has improved steadily, mainly by virtue of the removal action undertaken by Hercules/EPA. The improvement is reflected in relaxed state guidelines for fish consumption. Remedial actions completed in Terry Creek and at the Brunswick facility resulted in fewer restrictions on fish consumption as shown in the graph below.
*Silver perch - Brunswick facility not likely source of restriction
The completion of EPA’s selected interim remedy in 2025 will quickly and effectively prevent the outfall ditch from contributing to downstream contamination. The remedy will also promote future site redevelopment.
A long-term monitoring plan will make sure the interim remedy works as intended. EPA will determine if further actions are needed. Other portions of the Terry Creek site will be investigated and remediated as needed under the Superfund program. Investigations for the creeks and other areas are planned for late 2025.
Toxaphene does not dissolve in water and is not a groundwater contaminant at the Terry Creek site or at adjacent properties. Ongoing groundwater evaluations overseen by EPD support these conclusions. Nearby drinking water wells have been tested and neither toxaphene nor volatile organic compounds have been detected in the well water.
Outfall Ditch Remedy
As part of the approved remedy for Terry Creek, a new concrete-block stormwater conveyance channel has been built from the Brunswick plant to Dupree Creek, and the old outfall ditch has been filled and capped. Construction of the remedy was completed in July 2025.
Aerial photo from 2023 when construction on the new channel had just begun.
Aerial photo from August 2025 with grass beginning to grow over the cap atop the former Outfall Ditch.
What’s next
With the completion of the capping of the outfall ditch and construction of the new channel, Hercules will now focus on the investigation of soils and sediments in Dupree and Terry Creeks and the areas where the U.S. Army Corps of Engineers historically placed dredged spoils. The investigation will help Hercules and EPA understand remedial options for these areas.
Field crews sample the marsh in August 2025.