Testing for Crude Oil Contaminants in Louisiana’s Offshore Sediments (Field Sampling and Laboratory Protocol)
Authors: Steven Walker, PG (Terra); Bryan Rood, PG (Terra); Beau Suthard, PG (CPE); Jared Lambert (CPE),
Chris Pisarri (BEM), Landon Parr (BEM), Kesavalu M. Bagawandoss, PhD, JD (Accutest)
Name of Presenter: Steven Walker
Affiliation: Terra Environmental, Inc.
Address: 5555 W. Waters Ave, Suite 610
Tampa, FL 33634
Telephone Number: (813) 287-1444 Ext. 309
Email Address: SWalker@terraenv.com
Brief Biography of Presenter: Steven T. Walker, M.S., P.G. received his B.A. In Geology from New England
College and his M.S. in Marine Science/Geology from the University of South Florida, College of Marine Science,
St. Petersburg, Florida. Mr. Walker has 27 years of experience conducting and managing contamination-related
projects subject to federal and state regulations, including determining the nature and extent of hydrocarbon
contamination in soil, sediment, ground water and surface water. These projects have included the design and
conduct of sediment sampling and analysis programs and human health and ecological risk assessments in tidal and
lacustrine environments.
Abstract:
The Deepwater Horizon Oil Spill released approximately 4,900,000 barrels of crude oil during a 84-day event that
started on April 20, 2010. On May 11, 2010, the State of Louisiana requested an emergency permit from the United
States Army Corps of Engineers (USACE) to enhance the capability of the barrier islands to reduce the inland
movement of oil from the spill. On May 27, 2010, the USACE issued Emergency Permit NOD-20 partially
authorizing the project. Terra Environmental Services, Inc. (Terra) was retained by Coastal Planning &
Engineering, Inc. (CPE) to design and conduct an expedited monitoring program for sand borrow and rehandling
areas prior to initiating the State of Louisiana Coastal Protection and Restoration Plan for the Chandeleur Islands
and on all barrier islands from East Grand Terre Island eastward to Sandy Point. The sediment monitoring program
was a condition of the emergency permit. Results for the sediment assessments conducted under the emergency
permit were submitted to the State of Louisiana and USACE for review and acceptance as a condition of initiating
work in each of the borrow and rehandling areas. One hundred and thirteen locations were sampled from 11 areas
along the Mississippi and Louisiana gulf coast. The sampling and analytical testing programs for these areas were
developed by Terra based on its experience with hydrocarbon investigations, consideration of the various potential
end uses of the data (e.g. permit decision-making, human health and ecological risk evaluations, forensic chemistry,
Natural Resource Damage Assessments, etc.), and existing and emerging guidance for oil spill response.
Subsequent to Terra’s sediment monitoring program described above, the National Marine Fisheries Service
(NMFS) and the Louisiana Office of Coastal Protection and Restoration (OCPR) initiated voluntary crude oil
contaminant testing of the sediments associated with the West Belle Pass Barrier Headland Restoration Project (TE52); TE-52 is part of the Coastal Wetlands Planning, Protection and Restoration Act (CWPPRA) program. OCPR
had retained the services of CPE to design the TE-52 coastal restoration project. On behalf of NMFS and OCPR,
CPE contracted Balanced Environmental Management Systems, Inc. (BEM) to perform sediment assessments for
crude oil contaminants in the sediment borrow and deposition areas to determine if the areas were free from crude
oil contaminants associated with the Deepwater Horizon Oil Spill. The sediment sampling protocol and the crude
oil constituents of concern for the TE-52 areas were selected as a joint effort among NMFS, OCPR, CPE, and BEM.
Sediment samples were collected for TE-52 at 13 predetermined sampling locations between February 25, 2011 and
March 2, 2011 within two proposed borrow areas, the flotation channel area, and within the proposed restoration
area. The results of the sediment assessments would allow NMFS and OCPR to determine if TE-52 could move
forward into the construction phase. The sediment samples collected by Terra and BEM for the aforementioned
projects were analyzed for the following crude oil constituents of concern: volatile organic compounds (VOC)
benzene, toluene, ethylbenzene, and xylenes (BTEX); parent polycyclic aromatic hydrocarbons (PAH) and their
alkylated homologues; gasoline range, diesel range, and oil range petroleum hydrocarbons; and organic carbon.
BEM also included the analysis of metals (nickel and vanadium) and additional VOCs (cyclohexane,
isopropylbenzene, and methylcyclohexane) for sediment samples collected from their project locations. For the
Saint Bernard Shoals area, Terra included additional VOCs (cyclohexane, isopropylbenzene, and
methylcyclohexane) and metals (nickel and vanadium) in accordance with lease conditions. The above constituents
of concern were compared to selected Louisiana Department of Environmental Quality and USEPA Sediment
Benchmarks for Aquatic Life. Analytical results for all samples were below the human health and ecological
benchmarks selected for comparison and decision-making.