Latest News
- January 9, 2024: The U.S. District Court for the Eastern District of Virginia has approved the consent decreelodged by the City of Alexandria and Potomac Riverkeeper Network (PRKN), finalizing the proposed consent decree they jointly filed in November, when a settlement was reached to remediate potential remnants of coal tar in Alexandria as well as to resolve the complaint PRKN brought against the City in 2022.
- November 1, 2023: The City of Alexandria announced a settlement agreement with the Potomac Riverkeeper Network (PRKN) to remediate the remnants of coal tar contamination from the Alexandria Town Gas plant (N. Lee Street and Oronoco St.). To date, the City has spent over $12 million in remedial efforts since entering the site into the Voluntary Remediation Program (VRP) overseen by Virginia Department of Environmental Quality (VDEQ) and has $11.8 million programmed in its Capital Improvement Plan. This settlement is a continuation of the work and the unwavering commitment the City pursues to provide a safe, clean, and healthy environment for our residents, visitors, and future generations. For the full press release, please visit alexandriava.gov/go/5122.
Consent Decree Requirements and Work Completed to Date
The Consent Decree has four primary components: (1) an upland remediation program to expedite ongoing efforts to remove coal tar from the soil and groundwater; (2) further rehabilitation of the storm sewer pipe along Oronoco Street to keep any coal tar from entering the pipe and flowing into the Potomac River; (3) sediment testing and, if necessary, remediation in the vicinity of the Robinson Terminal North pier near the storm sewer outfall at the end of Oronoco Street; and (4) the City providing $300,000 to the Virginia Department of Wildlife Resources to fund a project to add over 20,000 freshwater mussels to the Potomac River.
The Consent Decree also requires the issuance of semi-annual reports summarizing remedial progress to date. A summary of the work completed and links to the semi-annual reports are provided below.
Summary of Consent Decree Work Completed
- October - December 2023: An in-well heating study was completed to determine if heating the groundwater at existing recovery wells would result in increased recovery of coal tar product. The findings shows that significant recovery did not occur due to heating the groundwater and it was recommended that new recovery wells be installed.
- November 2023: A TarGOST survey was completed to identify areas of remaining coal tar in the soil and groundwater. The City is currently working on a report to summarize the findings. This report will provide recommendations for where to install new recovery wells.
- April 2024: A camera was installed at the Oronoco Street stormwater outfall in order to meet the requirements of continuous monitoring.
- August 2024: Five new recovery wells were installed along the 100 block of Oronoco Street to aid in recovery additional free product from the soil and groundwater.
- August 29, 2024: A draft semi-annual report was prepared and submitted to the Potomac Riverkeeper Network for review and comment. The finalized report will be shared publicly following resolution of any review comments.
- September 2024: A contractor has begun work to rehabilitate the storm sewer on Oronoco Street between Fairfax and Union Streets. This project is scheduled to be completed in early November 2024.
- October 2024: The first semi-annual report has been finalized See the link below for the report and appendices:
Project Background
ABOUT THE ALEXANDRIA TOWN GAS – ORONOCO OUTFALL (ATG – ORONOCO) VOLUNTARY REMEDIATION PROJECT
The City of Alexandria continues to address environmental concerns associated with ATG – Oronoco. Since entering the site into Virginia’s Voluntary Remediation Program (VRP) in 2000, the City has made considerable progress towards securing this site.
ATG – Oronoco Site History
- Alexandria operated a manufactured gas plant (MGP) near the corner of North Lee and Oronoco Streets between 1851 and 1946. This plant produced coal-derived gas for residents and businesses in the City for heating, cooking, and lighting fuel.
- The production of manufactured gas created wastes, some of which remain at former MGP sites long after they cease operations. Over the decades many MGPs operated, a process byproduct called coal tar leaked from storage and processing facilities into surface soils, subsurface soils, and groundwater. Today, municipalities across the country, like Alexandria, are working to remediate sites contaminated by MGPs.
Summary of Past Corrective Actions
- Installation and operation of the floating oil containment boom around the outfall discharge area with additional oil absorbent booms installed and replaced periodically on the interior to collect contaminants.
- The City is currently operating a free product removal system that includes recovery wells installed in the source area. The removal of free product from the subsurface will make future remedial efforts more efficient.
- The City successfully completed the relining of portions of the Oronoco Street storm sewer in 2007 and 2014. The relining reduced the amount of oily substances infiltrating into the pipe and subsequently reduced the amount of impacted material being discharged to the Potomac River.
- In 2013, the City installed a groundwater treatment system beneath Oronoco Street. The system removes coal tar from groundwater before it discharges into the Potomac River. After nearly five years of operation, quarterly groundwater monitoring of wells located downgradient from the system indicate that the system is functioning properly.
- In April 2018, the bulk of affected sediments were removed and a reactive cap was installed over the remaining sediments to eliminate future seepage of coal tar into the river and cut off potential exposure pathways to human and ecological populations.
- In September 2019, the City cleaned and repaired a stormwater pipe in the 100 block of Oronoco Street to clear the residual coal tar from the pipeline floor and grout it.
- From March 2021 through April 2021, the City installed Non-Aqueous Phase Liquid (NAPL) recovery wells along Oronoco Street between North Lee and North Union Streets.
Contact Information
Erin Bevis-Carver, P.E.
Division Chief, Sanitary Infrastructure Division
Transportation and Environmental Services
703.746.4154
erin.beviscarver@alexandriava.gov