scispace - formally typeset
Search or ask a question

Showing papers on "Dredging published in 1983"


01 Jan 1983
TL;DR: The Journal of Waterway, Port, Coastal, and Ocean Engineering presents information regarding the engineering aspects of dredging, floods, ice, pollution, sediment transport, and tidal wave action that affect shorelines, waterways, and harbors as mentioned in this paper.
Abstract: The Journal of Waterway, Port, Coastal, and Ocean Engineering presents information regarding the engineering aspects of dredging, floods, ice, pollution, sediment transport, and tidal wave action that affect shorelines, waterways, and harbors. The development and operation of ports, harbors, and offshore facilities, as well as deep ocean engineering and shore protection and enhancement, are also covered. Other topics include the regulation and stabilization of rivers and the economics of beach nourishment.

95 citations


Journal Article
TL;DR: In this article, the authors studied benthic colonization following physical disturbance in shallow brackish waters at the SW coast of Finland, northern Baltic Sea, and showed the stock of colonizing species and the immigration distance to be major structuring factors in macrozoobenthic community development.
Abstract: Benthic colonization following physical disturbance was studied in shallow brackish waters at the SW coast of Finland, northern Baltic Sea. Following sand suction and periodic stagnation an annual colonization pattern is described in relation to continuous succession following channel dredging. The importance of different colonization mechanisms is discussed. The number of species recovers faster than abundance and biomass, and recovery from dredging may take as long as 5 years. Experiments show the stock of colonizing species and the immigration distance to be major structuring factors in macrozoobenthic community development.

38 citations



01 Oct 1983
TL;DR: In this paper, the authors assess the potential for placing a cap at the experimental Mud Dump site and to determine reductions in environmental impacts related to capping and determine if the capping effort yielded an intact cap showing resistance to erosion, and if the effort reduced loss of organic and inorganic toxicants from the contaminated material to the water column.
Abstract: : The objective of the project was to assess the potential for placing a cap at the experimental Mud Dump site and to determine reductions in environmental impacts related to capping. Contaminated sediment from dredging projects in the Hudson Estuary, Newark Bay, and contiguous waters were capped first with fine sediments from the Bronx River and Westchester Creek, then with sand from the Ambrose Channel. The capping resulted in a layer of sand about 1m thick lying atop the contaminated sediment. Physical, chemical and biological studies were carried out to determine if the capping effort yielded an intact cap showing resistance to erosion, and if the effort reduced loss of organic and inorganic toxicants from the contaminated material to the water column. It was determined that a cap was successfully placed at the experimental dump site. The cap was still intact and in place after 16 months. Cap erosion was minor; predictions of cap life were in excess of 20 years under normal meteorological conditions. Major storm events, however, are capable of eroding the cap and exposing the contaminated material. During the 16 months of study, the contaminated material decreased in volume by about 4%. Part of the decrease was due to compaction and part was due to loss of solids during dumping and deposition.

9 citations


Journal ArticleDOI
TL;DR: The results of the data collection program conducted by the New Orleans District of the U.S. Army Corps of Engineers in response to implementation of Section 404 of the Federal Water Pollution Control Act Amendment of 1972 and Section 103 of the Ocean Dumping Act are summarized in this article.
Abstract: The results of the data collection program conducted by the New Orleans District of the U.S. Army Corps of Engineers in response to implementation of Section 404 of the Federal Water Pollution Control Act Amendment of 1972 and Section 103 of the Ocean Dumping Act are summarized. The results of data collection during maintenance dredging are presented. Dispersion studies conducted during cutterhead pipeline dredging, an ocean dumping operation, and agitation dredging are described, and the results are summarized. Specific conclusions reached as a result of each phase of the data collection program are presented, and it is generally concluded that the material dredged during these investigations did not present a hazardous waste disposal problem, as dilution was rapid and increased concentrations of pollutants were confined to the disposal area or mixing zone.

6 citations


ReportDOI
TL;DR: The main purpose of this monitoring was to gather several years of data on PCB concentrations preparatory to removal of contaminated sediments by dredging, which was originally scheduled for the early 1980's as discussed by the authors.
Abstract: From purpose and scope: The main purpose of this monitoring was to gather several years of data on PCB concentrations preparatory to removal of contaminated sediments by dredging, which was originally scheduled for the early 1980's. Plans for dredging and disposal of sediments are currently being reevaluated. This report examines the contribution and transport of PCB's (polychlorinated biphenyls) from various reaches of the Hudson River and the changes in PCB concentration since 1977, when discharge was terminated.

5 citations


01 Jan 1983
TL;DR: The treatment of bottom sediments by solidification has increased in Japan in recent years as mentioned in this paper, and the applications of this method can be divided into four cases, which are discussed in this paper.
Abstract: : The treatment of bottom sediments by solidification has increased in Japan in recent years. This paper describes the state of the art in our country, citing some examples. The applications of this method can be divided into four cases, which are discussed in this paper.

4 citations




Journal ArticleDOI
01 Feb 1983
TL;DR: Bayou Casotte, Mississippi, an estuarine waterway near the eastern end of Mississippi Sound, has been altered to accommodate an extensive industrial complex including a large oil refinery as mentioned in this paper.
Abstract: Bayou Casotte, Mississippi, an estuarine waterway near the eastern end of Mississippi Sound, has been altered to accommodate an extensive industrial complex including a large oil refinery Several small oil spill accidents recently occurred in the bayou; the most serious, on June 13, 1981, involved 600 barrels of asphaltic crude The ecological effects of continued exposure to low level oily wastes were estimated by examining pollution levels in sediments both in 10-foot cores and surface samples Petroleum hydrocarbons (PHC) and other hydrocarbons occur at levels as high as 12,300 micrograms per gram (µg/g or ppm to total hydrocarbons, dry weight) in surficial sediments and 1,000 µg/g at 120 centimeter sediment depths Dredging operations have removed most polluted sediments very near the refinery site in the bayou, but dispersal of petroleum wastes has caused PHCs to be dominant pollutants in other regions where no dredging has occurred and where care is required if any dredging is permitted T

3 citations


Patent
24 Jun 1983
TL;DR: In this paper, an ejector type dredger is provided to the passage member through which a barge comes in and out in a dredged soil treatment pond and a vertically movable drain pipe to the barge.
Abstract: PURPOSE:To prevent the muddling of water surface during dredging period and the delivery and treatment period of dredged sludge by a method in which an ejector type dredger is provided to the passage member through which a barge comes in and out in a dredged soil treatment pond and a vertically movable drain pipe is provided to the barge. CONSTITUTION:Jet water ejectors 34 and 35 to inject jet water toward the inside of a pond and also to prevent the effluence of muddy water are provided to a passage member 30 through which a barge come in and out in a dredged soil treatment pond, and an ejector type dredger 7 to dredge bottom sludge in a water reservoir is provided to the dredger 6. Also, a vertically movable drain pipe 28 is provided to a barge 8 to house sludge dredged by the dredger 7 and to deliver it into the pond. Thus, by using the ejector of the dredger 7 to suck up deposit sand 2, dredging operation can be performed in a low-muddy state. Also, the overflow water of dredge sludge housed in the store chamber 24 of the barge 8 is discharged downwards into deep depth under the water surface through the drain pipe 28, and thereby muddling in the water reservoir can be prevented.

Patent
20 Jun 1983
TL;DR: In this article, a large diameter bull ring is affixed to the pivot sleeve of a dredging barge and a pair of cables connect to the bull ring and to a power driven winches on the spud barge.
Abstract: A dredging apparatus including a spud barge and a dredging barge. A hollow pivot sleeve is located at the stern of the dredging barge. A hydraulically extendable arm is mounted on the spud barge and is pivotally connected to the pivot sleeve. A large diameter bull ring is affixed to the pivot sleeve. A pair of cables connect to the bull ring and to a pair of power driven winches on the spud barge. The winding and unwinding of the cables around their winches swings the dredging barge about the pivot sleeve during dredging. An anchor spud extends through the hollow pivot sleeve to hold the dredging barge in fixed position when the spud barge is being relocated.

Patent
07 Oct 1983
TL;DR: In this paper, the authors proposed an improvement to dredging barges and more particularly to barges of modest overall dimensions, transportable by road in order to gain access to work sites of all types.
Abstract: The present invention relates to an improvement to dredging barges and more particularly to barges of modest overall dimensions, transportable by road in order to gain access to work sites of all types. The barge according to the invention comprises a hull 1 divided into compartments and a deck made from polyester around a rigid chassis on which are fixed, at the front, the means of dredging and laterally, means of the telescopic articulated leg type disposed, on the one hand, at the front in order to provide stabilisation and, on the other hand, at the rear to provide propulsion.

01 Jan 1983
TL;DR: In this paper, the key aspects and features of a trailing suction hopper dredge induced suspended sediment plumes during sand dredging at Middle Banks in Moreton Bay are discussed.
Abstract: The key aspects and features of a trailing suction hopper dredge induced suspended sediment plumes during sand dredging at Middle Banks in Moreton Bay are discussed. The two stages succeeding the generation phase in the development of dredge suspended sediment plumes that can be distinguished are highlighted.

Patent
06 Apr 1983
TL;DR: In this paper, a method in which a cylinder from the bottom opening of a base ship is brought down to the bottom under water, a horizontal skirt of an elastic plate is alike brought down around the cylinder, and deposits inside the cylinder are dredged.
Abstract: PURPOSE:To perform the dredging of marsh, etc., without causing water to muddle by a method in which a cylinder from the bottom opening of a base ship is brought down to the bottom under water, a horizontal skirt of an elastic plate is alike brought down around the cylinder, and deposits inside the cylinder are dredged. CONSTITUTION:When dredging deposite 8 on the bottom under water, a cylinder 3 attached in a vertically movable manner to the bottom opening 2 of a base ship 1 is brought down, and its lower part 4 is landed on the bottom 5 and deposits 8 are housed in the cylinder 3. Then, a horizontal skirt 7 made of an elastic plate is gradually brought down to the surrounding of the cylinder 3 by means of a wire 6 and landed on deposits 8 a pressing manner from above, and then the deposits 8 are scooped up to the base ship 1. Thus, dredging work can be sanitrarily performed without stirring deposits 8 surrounding the cylinder 3 and also causing water to muddle during the dredging period.

Proceedings ArticleDOI
01 Jan 1983
TL;DR: In this paper, a framework for the coordination of port and harbor dredging projects is proposed, and case studies from Gloucester Harbor and the Port of Boston, Massachusetts are presented.
Abstract: "Master Plans" for ports commonly focus on development, land use, and environmental issues but generally fail to include recommendations to coordinate plan implementation. As a result, various port projects involving construction and dredging are initiated independently, and this results in few economic or environmental benefits to the proponent or the general public. If environmental testing, permitting, and dredging for the projects were combined, substantial savings in time and money could be realized by port users and environmental impacts to public resources could be reduced. This paper suggests a framework for the coordination of port and harbor dredging projects and presents case studies from Gloucester Harbor and the Port of Boston, Massachusetts, where this framework has successfully been implemented.

01 Jan 1983
TL;DR: In this paper, the Oozer pump dredge was used for test dredging in Osaka Bay where bottom sediments contain severe organic contamination, and the results showed that the sludge may be efficiently dredged with the suction mouth of the dredge swinging back and forth along the seabed; by setting the swing speed for dredging from 6 to 7 m/min. or less, little contamination occurred.
Abstract: : Test dredging was carried out with cutterless dredges in Osaka Bay where bottom sediments contain severe organic contamination. The Oozer pump dredge was also studied in this test work. The following results were obtained: The sludges may be efficiently dredged with the suction mouth of the dredge swinging back and forth along the seabed; By setting the swing speed for dredging from 6 to 7 m/min. or less, little contamination in the vicinity of the suction mouth occurs; The efficiency of the dredge is approximately 250 wm/hr on the average, with a concentration of 30 to 40 percent by volume; The sludge dredged may be efficiently disposed of by transporting it on a barge to the disposal site; and The advantage of the Oozer pump dredge lies in that little excess water is sucked in while dredging which facilitates disposal of the slurry.

Patent
13 Sep 1983
TL;DR: In this article, the authors proposed to attain stable dredging work all the time by injecting water above deposited soil and sand from an annular waterway between an underwater device and a box into the surrounding of a suction port by means of the suction force of the underwater device when burying the SUction port.
Abstract: PURPOSE:To attain stable dredging work all the time by injecting water above deposited soil and sand from an annular waterway between an underwater device and a box into the surrounding of a suction port by means of the suction force of the underwater device when burying the suction port. CONSTITUTION:An underwater device 1, having a lower end near its lower suction port 2 and a box 5 covering the device 1 and having an opening in water above an imaginary deposit level on its upper end, is settled on the bottom under water and dredging work is started. In the course of the dredging work, when the suction port 2 of the underwater device 1 is buried by the falling of surrounding soil and sand, water above the burying soil and sand is injected from an annular waterway F between the device 1 and the box 5 into the surrounding of the suction port 2 by means of the suction force of the underwater device 1. Thus, the fluidity of the soil and sand is improved and stable dredging work can thus be attained even when the suction port 2 is buried.

Posted Content
TL;DR: In this article, a total-system perspective with regard to costs and benefits of coal-port development is presented, assuming that society will both pay the costs and receive the benefits from coal port development.
Abstract: This study deals with the question of whether US society as a whole should invest in large-scale coal-port development. The analysis takes a total-system perspective with regard to costs and benefits. The analysis does not try to attribute the costs or benefits of dredging to the various parties involved in the coal trade. Rather, the analysis assumes that society, as a whole, will both pay the costs and receive the benefits from dredging. The study lends support to those recommending caution in approaching coal-port development. There was no justification for dredging all deep-draft options simultaneously. In fact, what is very clear is that the concurrent dredging of more than one port is unwise unless one supports the most-optimistic projections for coal-export demand or relatively low real interest rates over the long run. Moreover, under no condition examined does it make sense to dredge either of the Gulf ports - Mobile or New Orleans - before dredging Hampton Roads or Baltimore. 35 references, 30 tables.