Study Summary: Water and Sediment Chemistry
After the April 2000 Potomac Electric Power Company (PEPCO) pipeline oil
spill near Benedict, Maryland, the National Oceanic and Atmospheric
Administration (NOAA), the U.S. Fish and Wildlife Service (FWS), the Maryland
Department of Natural Resources (MDNR), and the Maryland Department of the
Environment (MDE) are assessing and restoring injured natural resources. This
effort, called a natural resource damage assessment (NRDA), involves
implementing studies to identify and quantify injured resources and services.
This fact sheet provides summary information about one of the studies being
The objective of this study is to document the geographic extent and magnitude of petroleum hydrocarbons over time in the Patuxent River and its tributaries. Data from these studies are also being used to quantify the exposure of aquatic resources to the spilled oil.
Water and sediment samples were collected for petroleum hydrocarbon analysis
using general sampling and documentation procedures outlined in the Natural
Resource Damage Assessment Emergency Guidance Manual (NOAA 1997).
There have been five studies that focused on water and sediment chemistry.
These surveys were initiated within 24 hours of the release and continued
through August 2000. During the first 5 days of the spill, three separate
studies were conducted in Swanson Creek and the Patuxent River. In general,
these surveys consisted of collecting water samples from near the surface of
the water column and surface sediments. The first survey was conducted on April
8 in Swanson Creek. The second survey was conducted on April 10 in Swanson
Creek and the Patuxent River. The third survey was conducted April 12–13
between Black Swamp Creek (located 6 miles upstream from Swanson Creek) and
Broomes Island (approximately 11 miles downstream from Swanson Creek). During
this survey, sampling was conducted in the mainstem of the Patuxent River and
in seven tributaries including Swanson Creek, Indian Creek, and Trent Hall
Creek. The fourth study consisted of 10 sampling surveys at up to 26 stations
in the Patuxent River between April 17 and July 11. The fifth survey was
conducted throughout the spill area in August 2000. Samples were collected
between Deep Landing (approximately 4 miles upstream of Swanson Creek) and
Field surveys and requested laboratory analysis are complete for the initial
five surveys. Some samples have been archived pending further analytical
review. Reports are currently being prepared by the field investigators.
Findings from these studies will be used to assess the level of injuries to
aquatic resources. Additional water and sediment sampling is scheduled through
at least 2001 as part of the long-term monitoring program.
The first and second surveys were developed and implemented by representatives
of FWS and PEPCO. The third survey was developed by the NRDA Council consisting
of representatives of NOAA, FWS, MDNR, MDE, ST Services, and PEPCO. The fourth
survey was conducted by the University of Maryland–Chesapeake Biological
Laboratory with assistance from representatives of the NRDA Council. The fifth
study was developed and implemented by PEPCO representatives with approval and
oversight from the U.S. Environmental Protection Agency and approval of state
and federal resource agencies (NOAA, FWS, MDNR, and MDE).
For More Information
Contact one of the following individuals or visit a web site for more
NOAA Damage Assessment Remediation and Restoration Program
1305 East West Highway
Building 4, Room 10218
Silver Spring, MD 20910
This summary is meant to provide only an overview. More information on NRDA studies can be found in the Swanson Creek
administrative record located at the following sites:
Light Point Commerce Center
30383 Three Notch Road
Charlotte Hall, MD
Monday–Friday, 9 a.m. to 5 p.m.
Calvert Industrial Park
230 Bugeye Square
Prince Frederick, MD
Monday–Friday, 9 a.m. to 5 p.m.
Information Resource Center
Maryland Department of Natural Resources
580 Taylor Avenue, B–3
Annapolis, MD 21401
Monday–Friday, 8 a.m. to 4 p.m.