Tybouts Corner Landfill
EPA ID: DED000606079
New Castle County, DE
Congressional District: 1st
Other Names: None
Last Updated: January 2015
The EPA is dedicated to providing you with timely and accurate information about our work at this site. If you have any questions or concerns, please contact:
800-553-2509 or 215-814-5526
On This Page
- EPA continues to monitor the groundwater and air to ensure the remedy remains protective.
- The third Five Year Review for the Site was completed on September 29, 2010. This review found the remedy to remain protective of human health and the environment. The next Five Year Review is scheduled to be completed by September 2015.
- Construction activities for this Site were completed in September 1995. Operation and maintenance activities associated with the landfill cap, gas extraction system, and the monitoring system(s) are ongoing.
- Groundwater monitoring results demonstrate that the concentration of contaminants in the ground water are approaching cleanup levels. The pumping wells were shut down in May 2007.
- Tybouts Corner Landfill Site is located in New Castle County, Delaware approximately 10 miles south of Wilmington and four miles west of the Delaware River.
- The Site was used by the New Castle County Department of Public Works as a municipal sanitary landfill that also accepted industrial wastes from December 1968 until July 1971.
- The landfill consisted of two noncontiguous sections, a west landfill that was about four acres in size and the main landfill that was about 47 acres, ranging from five to 40 feet thick.
- Contamination was found in two nearby wells in 1976 and again in 1983, prompting listing on the National Priorities List.
NPL Listing History
|Status:||Proposed: December 1982|
|Deleted:||Final: September 1983|
- The cleanup remedy for this Site was completed in 1995. The remedy consisted of :
- A groundwater pumping system consisting of eight extraction wells to contain contaminated groundwater at the landfill;
- a subsurface slurry wall to prevent clean groundwater from entering the landfill;
- a multi-layer cap to prevent rain from entering the waste material in the landfill;
- and a passive venting system to prevent the build-up of landfill gases within the landfill.
- When landfill gas was detected outside the boundaries of the landfill in 1996, a temporary active gas venting system was installed.
- A permanent active gas venting system was installed in 2000.
- During the last 12 years, quarterly sampling of groundwater has been conducted to ensure the remedy is functioning as designed.
- In May 2007 contaminant concentrations in groundwater decreased significantly and EPA and DNREC agreed to shut down the pumping wells.
- Quarterly monitoring of the groundwater ceased in 2008, the wells are now sampled semi-annually.
- Samples are collected from the gas vents and the data is incorporated into an air model on an annual basis which evaluates any risk associated with exposure to the air emissions.
- The most recent air modeling of the vent data demonstrated that emissions from the vents do not present an unacceptable risk to human health.
- The active gas venting system is effective in preventing the migration of underground landfill gas beyond the landfill property boundary.
- Annual monitoring of the passive landfill gas vents continues.
- The Site was ranked on the NPL in 1983 due to a threat of contamination of the regional aquifer, the primary source of water in this region in Delaware.
- The Site also presented a threat to domestic wells in the immediate vicinity. In 1985, EPA installed a water line to supply homes in the vicinity of the Site with public water.
- The contaminants of concern include vinyl chloride, benzene, and 1,2-dichloroethane, and various other organic and inorganic chemicals.
- Contaminant descriptions and associated risk factors are available at: (ATSDR web site).
- To search an on-line database of all documents and reports on the Tybouts Corner Landfill site, go to EPA’s Administrative Record Database.
- All documents and reports can also be reviewed in person at these locations:
Delaware Department of Natural Resources & Environmental Control,
391 Lukens Drive
New Castle, DE 19720
U.S. EPA Region 3 NPL Public Docket
c/o U.S. EPA Region 3 Library
1650 Arch Street, 2nd floor (3PM52)
Philadelphia, PA 19103-2029
- Some of the site’s key documents of interest are accessible below.
Record of Decision
- Submit a FOIA Request
Get instructions on how to submit a FOIA request. $Fee$ for requests over 100 pages.
- Fact Sheet
- Public Notice
April 2015 (PDF) (1 pg, 290 K)
April 2010 (PDF) (1 pg, 513 K)