Purpose and Scope

material (a glossary of terms used in this report is found in Appendix A).

Capping of contaminated dredged material in open-water sites began in

the late 1970s, and a number of capping operations under a variety of

placement conditions have been accomplished. Conventional placement

equipment and techniques are frequently used for a capping project, but

these practices must be controlled more precisely than for conventional

placement.

Purpose and Scope

This report provides guidance for evaluation of subaqueous dredged

material capping projects. Design requirements, a design sequence, site

selection, equipment and placement techniques, geotechnical considera-

tions, mixing and dispersion during placement, required capping sediment

thickness, material spread and mounding during placement, cap stability,

and monitoring are included. From a technical perspective, this guidance

is applicable to dredged material capping projects in ocean waters as well

as inland and near-coastal waters.

The technical guidance in this report is intended for use by USACE

and EPA personnel, State regulatory personnel, as well as dredging permit

applicants and others (e.g., scientists, engineers, managers, and other in-

volved or concerned individuals).

Regulatory Setting

Capping involves placement of dredged material in either ocean waters

or inland and near-coastal waters (waters of the United States). The pri-

mary Federal environmental statute governing transportation of dredged

material to the ocean for purpose of placement is the MPRSA, also called

the Ocean Dumping Act. The primary Federal environmental statute gov-

erning the discharge of dredged and/or fill material into waters of the

United States (inland of the baseline to the territorial sea) is the Federal

Water Pollution Control Act Amendments of 1972, also called the CWA.

All proposed dredged material placement activities regulated by the

MPRSA and CWA must also comply with the applicable requirements of

the NEPA and its implementing regulations. In addition to MPRSA,

CWA, and NEPA, there are a number of other Federal laws, Executive Or-

ders, etc., that must be considered in the evaluation of dredging projects.

The London Convention (Convention on the Prevention of Marine

Pollution by Dumping of Waste and Other Matter, December 29, 1972

(26 UST 2403:TIAS 8165)), to which the United States is a signatory, is

an international treaty that deals with marine-waste placement, with juris-

diction that includes all waters seaward of the baseline of the territorial

sea. The ocean-dumping criteria developed under MPRSA are required to

"apply the standards and criteria binding upon the United States under the

Chapter 1 Introduction