Recently Susan Pastor with the U.S. Environmental Protection Agency wrote an article in the Spring 2012 edition of the Fox River Current titled “Latest Technology Guides Hydraulic Dredge”. The article was about the use of a Real Time Kinematic Global Positioning System (RTK-GPS) to aid the dredge operator in removing contaminated sediments from the Fox River in Green Bay, WI. In the article she writes about the use of the system and how it improves the accuracy in which a dredge operator can remove targeted sediments to designated depths. These operators can view their progress in real time using pricey, high accuracy equipment.
The reason a system like this is so beneficial to environmental dredge projects is because it can substantially reduce the overall cost. Due to the high cost of treatment and disposal of contaminated sediments, it is imperative that the quantities be minimized. Taking clean, underlying soils with the contaminated sediments will only inflate the overall cost of the project because once mixed, it all needs to be treated. The RTK-GPS system used in combination with customized software, positioning sensors, and an experienced operator are necessary to effectively remove all the contaminated sediments, while minimizing removal of clean sediments.
This theory goes against the grain of the entire concept of dredging. Since its inception, the goal has always been to remove as much material, as fast as possible. It is known as maximizing production. However, to maximize production inenvironmental dredging, one must surgically remove these sediments as efficiently as possible. High-accuracy equipment, such as RTK-GPS, and an experienced operator are the best ways to accomplish this extremely difficult task.