July 31, 2003
Bollinger yards make dustpan dredge deeper
Two Bollinger shipyards have teamed to increase the dredging depth of the Pine Bluff Sand and Gravel Co. dustpan dredge, WALLACE McGEORGE, from 62-feet to 75-feet, enabling it to dredge at higher river stages and dispatch sooner on a falling river.
In the process, Bollinger Quick Repair, Harvey, La., fabricated and installed 45-ton, 36-foot by 20-foot, port and starboard sections to the horn of the dredge, increasing the vessels overall length from 252.5 feet to 288.5 feet. The yard then installed a new 46-ton, 40-foot wide by 15-foot by 30-foot high, A-frame that it had prefabricated for the dredge.
The A-frame--which actually is more like an inverted "U"-- accommodates a new "ladder" that was fabricated at Bollinger Gulf Repair, New Orleans and installed at Bollinger Quick Repair.
"By assigning the work to two of our shipyards, we were able to complete the entire job in just over three months," said Allen Stein, operations manager of Bollinger.
The 120-foot long by 17-foot wide, 93-ton ladder is fitted between the legs of the A-frame and the two new hull sections so it can be raised or lowered to the required dredging depth. The 20-ton, 30-foot-1/4 inch wide dustpan suction head tips the lower "business" end of the ladder. The dustpan, which can be likened to a vacuum cleaner, is very efficient in excavating sand material from river bottoms. When the suction head is lowered to the river bottom, high velocity water jets on the suction head loosen the material, which is then drawn up by a single hull pump and transported through a floating pipeline mounted on pontoons and deposited outside navigation channels.
An EMD 20-645-E4-diesel engine powers the pumping and suction systems and the boats propulsion power is supplied by two Caterpillar 3516 diesels driving through Ulstein Z-drive units.
Ducote Engineering Associates, Inc. of Jefferson, La. provided design and engineering services for the project.
The WALLACE McGEORGE is under contract with the U. S. Army Corps of Engineers (USACE), Memphis District, to help maintain Mississippi River deep draft crossings between Baton Rouge and the Gulf of Mexico. According to Joaquin Mujica, USACE operations manager for South Louisiana ports, this area includes the largest U.S. ports based upon tonnage.
Mujica said the modified WALLACE McGEORGE will give the USACE a "bigger stick," meaning deeper dredging capacity. He said dustpan dredges are more advantageous than cutterhead dredges in certain applications as they are self-propelled making them more mobile. He added that dustpan dredges are more economical than cutterheads for deep draft channel crossings.
Mark Lemoine of Pine Bluffs Alexandria, La. office said Brown and Root built the WALLACE McGEORGE, whose original name was CARL BURKHARDT, in 1965 as a cutterhead dredge. Around 1980, it was converted to a dustpan dredge and renamed LENEL BEAN by Bean Dredging, who had acquired the vessel. In 1991, Pine Bluff bought the vessel and later renamed it WALLACE McGEORGE, for a member of the companys second generation of owners.
David Marmillion, Sr., Bollinger vice-president/inland river operations said, "The WALLACE McGEORGE modification is another example of our versatility and ability to serve many segments of the marine industry in ship repair, conversion, retrofitting and new construction. Over the years we have inspected, serviced, rebuilt, repaired, remodeled, reconditioned or merely sandblasted and painted thousands of inland waterways vessels. We have modified and done other work on this and other Pine Bluff vessels and we are pleased they selected Bollinger for this project."
According to Scott McGeorge, President of Pine Bluff Sand & Gravel Company, which is headquartered in Pine Bluff, Arkansas, the company will celebrate its 90th birthday in November, 2003. The company performs work primarily for the U.S. Army Corps of Engineers concentrating on Marine Construction and Dredging projects in Arkansas, Tennessee, Mississippi, Louisiana and Texas.