Dredging in Unexploded Ordnance (UXO) Contaminated Sediment

Category:

Operating Procedures

Safety Procedures

Description:

The USACE Buffalo District conducted a demonstration dredging project in the Toussaint River,

Ohio, to evaluate the operational effectiveness of a modified clamshell bucket dredging process

designed to separate over screens and retrieve UXO from sediment prior to its disposal. During

the 79- work-day duration of the demonstration project, 72 dredge days removed 19,000 yd3 of

material from the authorized channel limits. A total of 37 pieces of ordnance, 6 of which were

unexploded ordnance (UXO) were recovered from the separation screens and properly disposed

of. An overall production rate of 26.8 yd3/hour or 268 yd3/day was attained by the clamshell

dredge operation at a cost of $25.34/yd3. The total demonstration production cost was

$43.15/yd3, as opposed to an average cost of less than $5.00/yd3 for conventional dredging in

this part of the Great Lakes.

The "Atlantic Coast of New Jersey, Sandy Hook to Barnegat Inlet, Section 1, Sea Bright to

Ocean Township" project is the largest beach restoration project ever undertaken in the United

States. The borrow source for the restoration project was found to contain several types and

calibers of ordnance after dredging with hopper dredges was initiated. Cleanup operations were

required to locate and remove the ordnance from the beach, and Explosives Ordnance Disposal

(EOD) personnel were called in several times to remove ordnance from the hopper dredge. The

dredging contracts that have been awarded since this 1994 contract for both hopper and hydraulic

pipeline dredges were required to install 38-mm (1.5-in.) -spaced bars on the suction intakes. The

cost per cubic yard of sand delivered to the beach has not exceeded $4.00/yd3.

Reviewer:

C. Woolley

Company / Organization(s):

Access Restricted to U.S. Army Corps of Engineers

Projects Completed:

Atlantic Coast of New Jersey, Sandy Hook to Barnegat Inlet, Section 1, Sea Bright to Ocean Township

Location:

Atlantic Coast of New Jersey

Completion Date:

1994-1998

Project Contact:

USACE: New York

Project Cost:

$150,000,000

Estimated Cost:

Nominal

Comments:

The cost per cubic yard of sand delivered to the beach has not exceeded

$4.00/yd3. This may be due to proprietary contractor improvements to the

dredging equipment, and the competitive bidding process.

Toussaint River UXO Demonstration Dredging Project

Location:

Toussaint River, Ohio

Completion Date:

October 1995

Project Contact:

USACE:Buffalo

Project Cost:

$850,000

Estimated Cost:

$740,000

Information Sources:

Literature:

Title:

"Dredging in Unexploded Ordnance (UXO)-Contaminated Sediments"

Author:

T.L. Welp, R.L. Pilon

Month:

June

Year:

1998

LitType:

Report/Proceedings

Publisher:

WODCON XV, Las Vegas

Page:

481

Chapter 5 Other Technologies Reviewed