Contaminated Marine Sediments Assessment and Remediation (1989) / Chapter Skim
Currently Skimming:
Monitoring the Effectiveness of Capping for Isolating Contaminated Sediments
Monitoring the Effectiveness of Capping for Isolating Contaminated Sediments
Pages 262-279
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 262... ...
. This project, which took place in 20 m of water in the eastern end of Long Island Sound, has led to continued application and field observations of the technique, including major capping operations at the Central Long Island Sound Disposal Site (CLIS)
|
From page 263... ...
HISTORY OF CAPPING OPERATIONS The first use of capping as a disposal management strategy occurred at the New London Disposal site (NLON) in 1977 when contaminated sediments from the vicinity of dock areas were dredged first and then covered with cleaner sediments as dredging proceeded from the head of the estuary to the mouth.
|
From page 264... ...
Disposal of capping material must be spread over a larger area. Dispersal of cap material is necessary to ensure adequate capping of the margins of the contaminated deposit and is particularly important for silt capping material, which does not spread as evenly as sand.
|
From page 265... ...
265 _ 1 1 _ G _ _ 1~ I to 1 (D W 1 · to ~ G t~= L~ Lie 1~ 1 ~ .
|
From page 266... ...
As a result of these studies, the factors affecting capping can be predicted with some accuracy, particularly the amount of material needed to create an effective cap and the controls necessary to dispose of the contaminated sediment and capping material in a stable deposit. DAMOS MONITORING PROGRAM As stated above, future capping projects are certain to require extensive monitoring programs, which will be required to evaluate the effectiveness of the capping operation and address site-specific issues.
|
From page 267... ...
Isolation of contaminated material: both chemical and biological monitoring have demonstrated that, given sufficient cap thickness and stability, neither bioturbation nor chemical leaching will expose contaminated sediments to the surrounding environment. Therefore, use of uncontaminated sediments as a cap material is a viable method for isolation.
|
From page 270... ...
On the DAMOS program, buoy deployment and sampling are controlled through an SAIC Integrated Navigation and Data Acquisition System (INDAS) , which provides computerized integration of microwave or acoustic positioning systems with environmental sensors and navigation displays to provide accurate ship control and data acquisition.
|
From page 271... ...
271 , _ _ _ 1 ~ 11 1- 1 ~ + ~ 1 -: rot rot I I ~ _ ~ ~ 1: ~ + + + BA: + ~ + ~ ~ CD ~ Z ~~= ~ : _ 1 in' ~ im 11 a' · ~n U)
|
From page 272... ...
Foul Area Disposal S ite ~ PADS ~ Extensive disposal site designation studies have recently been conducted at FADS, including investigation of the potential effects of capping operations in water depths of 90 m. Disposal at FADS generally occurs from disposal scows and, occasionally, from hopper dredges;
|
From page 274... ...
274 To o Or no o o ..~ o A o 1 1 1 1 (D 1 al ~ 1 a ;> L~1 := ~ := O O O to ~ ~ .
|
From page 275... ...
In shallow water, cohesive sediments disposed under the influence of the above disposal phases create a distinct mound formation with thin flank deposits, while sands, or less cohesive, high-water-content sediments characteristic of the contaminated material produce a broader, more uniform deposit. At FADS, mounding of cohesive sediments was less prevalent even with cohesive sediments; however, the overall spread of material was similar.
|
From page 276... ...
276 _ ~ ~ ~ ~ V, ~ _~ ~ -+ Ha X3 ~ X2 xs=~-~" x -- ~" am L=.
|
From page 277... ...
Therefore, appropriate scheduling of small contaminated projects prior to larger uncontaminated dredging programs must be carefully considered. SCARY Extensive monitoring of capping projects throughout the New England region under the DAMOS program suggests that capping is a a feasible mitigating measure for disposal of contaminated sediments in the marine environment.
|
From page 278... ...
278 t - _ I ~ ~ ~ 1~ m ' ..^ _ C_,W to + ~ Ax w ~ C w W — _ G ~ ~ 0~)
|
From page 279... ...
LIST OF DAMOS CONTRIBUTIONS SUBMITTED TO NEW ENGLAND DIVISION U.S. ARMY CORPS OF ENGINEERS # 7 Stamford/New Haven Disposal Operation Monitoring Survey Report # 8 Management and Monitoring of Dredge Spoil and Capping Procedures in Central Long Island Sound #11 "Capping" Procedures as an Alternative Technique to Isolate Contaminated Dredge Material in the Marine Environment #12 Precision Disposal Operations Using a Computerized Loran-C S:8ystem #17 Disposal Area Monitoring System Annual Report, 1980 #22 DAMOS Mussel Watch Program: Monitoring of the "Capping" Procedure Using Mytilus edulis at the Central Long Island Sound Disposal Site; 1980-81.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.