University of Wisconsin-Madison College of Engineering Annual Report 2003
UW-Madison College of Engineering banner 
2003 Annual Report banner
 

Home

Civil and Environmental Engineering

Jim Park and Min Jang

Removing arsenic from groundwater:
An easier and cheaper way

All groundwater contains arsenic. Removing that arsenic ensures that the groundwater can be safely converted into drinking water. But in many sections of the world, particularly in developing parts of Asia, building systems for removing arsenic can be problematic or expensive. In an effort to ensure safer drinking water worldwide, Professor Jim Park left) and graduate student Min Jang have developed an adsorbent that can remove arsenic from water at faster rates and lower costs than current methods.

Most of the tap water we drink comes from aquifers underneath the ground. This groundwater carries with it arsenic, just one of the many metals and minerals that are released from rocks. When ingested in moderate concentrations over time, arsenic can cause skin disorders, tumors, breathing problems and organ damage. To remove arsenic, groundwater is filtered through treatment systems that contain small, porous particles called activated alumina. These particles catch molecules of arsenic as water passes over them.

According to Park, the small pore size and small surface area of the activated alumina particles limit the number of arsenic molecules that the particles can trap. Park and Jang have developed a particle that more effectively adsorbs arsenic from water as it's being treated. The particle, made from a mesoporous media developed by Mobil scientists in 1992, could be used anywhere from wells to treatment plants to home faucet filters. Unlike the particles of activated alumina, Park's particles are bigger and have larger pores that are all the same size. They're also coated with metal oxides that react only to arsenic — a quality, he says, that could keep many healthful minerals, usually removed by activated alumina, in the water. Park said he hopes to soon begin testing the particle in South Korea.

From sludge to state park — renewing the land

What was once contaminated sludge has been converted into a section of Wisconsin's newest state park, thanks to the help of Professor Tuncer Edil and a team of students.

Edil, working with the Madison Metropolitan Sewerage District, devised an innovative method for capping a district lagoon system filled with very soft sludge contaminated by high levels of polychlorinated biphenyls (PCBs). The project was honored in the fall of 2002 with the Engineering Achievement Award by the Wisconsin Section of the American Society of Civil Engineers.

Edil and his team of students developed a method that involved covering the lagoons with a layer of ice as a platform to support construction equipment. A mixture of soil and woodchips was placed on top of a geotextile (a woven sheet of polymer) that sat atop the layer of ice. During the spring thaw, the ice layer melted, allowing the geotextile cover and the soil/chip mixture to cap and seal off the lagoons. The sealed-off lagoons were then seeded for a vegetative cover. Work on capping the lagoons was completed during four winter construction seasons. The capped lagoons have worked out so well that they were recently included within the boundaries of Wisconsin's new Capital Springs Centennial State Park.

Traffic studies aim to end driver confusion

Basic traffic signaling — a red sign for stop, or a green light for go — is universally understood. But the application of traffic signaling varies widely across the country, and leads to confusion among drivers, according to research by Assistant Professor David Noyce.

For instance, Noyce said driver survey studies indicate considerable confusion about left turns and left turn signals. Drivers are often confused when confronted simultaneously with a red signal indicating "stop" and a green left-turn arrow that permits a driver to move through an intersection. This is particularly true with elderly drivers, he said.

Noyce's research is part of a large, national research project into driver habits and understanding of turn signals. The research included an extensive study using driving simulation technology, the largest study of its kind completed nationally.

Noyce's research is already attracting the attention of national and international transportation experts. His paper received the Transportation Research Board's annual D. Grant Mickle Award for the best paper of the year in operation, safety and maintenance of transportation systems. One goal of the research is to provide detailed information to the Federal Highway Administration so it can recommend more uniform traffic control devices. That could in the long run help reduce traffic fatalities that this year will total more than 800 in Wisconsin and more than 40,000 nationwide, according to Noyce.

 





University of
Wisconsin-Madison College of Engineering logo

Copyright 2003 The Board of Regents of the University of Wisconsin System
Content: perspective@engr.wisc.edu
Web: webmaster@engr.wisc.edu
Date last modified: Friday, 03-Oct-2003 12:56:00 CDT
Date created: 03-Oct-2003