Students to demonstrate how to clean, seal soil

After months of hard work, four MIT students will head to New Mexico this Saturday to compete in an environmental design contest against 25 other university and college teams.

There, the students, who represent a nine-member MIT team, will present solutions to the contest's two-part challenge: (1) a proposal for the cleanup of five acres of contaminated soil, and (2) the identification of an aid for "water-harvesting," a technique to enhance the growth of vegetation in arid lands.

For the second part of the challenge, competitors were specifically asked to come up with a water-resistant "sealant" that could be applied to large areas of soil. Rain draining off the soil could then be used for irrigation.

This is the first year that MIT will compete in the fourth annual WERC International Environmental Design Contest. The contest, which features $35,000 in prizes, is hosted by the Waste-Management Education and Research Consortium (WERC). It will be held April 10-14 on the campus of New Mexico State University in Las Cruces.

MIT got involved in the contest after Professor Rafael Bras, head of the Department of Civil and Environmental Engineering (CEE), sent information about it to the civil engineering honor society, Chi Epsilon. Karen Schmitt, a junior in the department, was intrigued and began recruiting people from around the Institute (the final team includes two freshmen and students from CEE, ocean engineering and mechanical engineering). Dr. John Germaine, a principal research associate in CEE, is advisor for the project.

The students began developing their entry last fall. Since then they've spent hours not only coming up with solutions to both parts of the challenge, but researching the economic, lega- and health issues associated with them. For example, "we had to make sure [our solutions] complied with all environmental regulations and we had to develop a business plan," said Ms. Schmitt, who is manager for the MIT team.

The contest also generated some unexpected work: the students had to duplicate the soil provided by WERC to have enough soil for testing here at MIT. "That was a project in and of itself," Ms. Schmitt said.

Overall, she said, "this has definitely been more work than any of my 12-unit classes." (Although the contest is an extracurricular activity, the students did receive 3 units of credit for an IAP course on the contest.)

In New Mexico the students will submit a paper on their solutions, give an oral presentation, present a poster session and demonstrate their solutions on a small scale with soil samples provided by WERC.

What did they come up with? For the soil remediation part of the contest, the group developed a "soil extraction and heating process," Ms. Schmitt said. "We're basically going to dig up the soil then wash it in a mixture of acetone, alcohol and water, which should remove most of the contaminants. Then, since [the hypothetical site is] in New Mexico, we're going to use solar ovens to burn off the rest of the contaminants."

In devising this solution, the team took advantage of the following contest assumptions: there is adequate space to store the contaminated soil for one year, and the contaminants only penetrate to about one foot below the surface of the ground.

At the contest they'll test their solution on five kilograms, or "five small zip-lock bags full," of contaminated soil provided by WERC, Ms. Schmitt said. (For testing at MIT the students had to contaminate the soil themselves with the ten pollutants stipulated because WERC couldn't send them contaminated soil in the mail.)

For the second part of the contest, the group came up with a viable soil sealant. "It's basically a pine oil emulsion," Ms. Schmitt said. "We're diluting it with water and spraying it on the soil." In New Mexico the group will test the concoction in a small sandbox tilted at a 30 degree angle. (In addition to showing water-resistant properties, the winning sealant must prevent erosion on slopes.)

Ms. Schmitt noted that the pine oil the MIT team is using is a commercial product, "but it's never been used for this type of application." And that generated another unexpected twist related to the contest: the company that produces the oil called her last week "to ask if they could distribute our research to some of their other clients." (For the contest-and accordingly for this article-teams aren't allowed to report any trade names or companies of products used.)

For the final part of the contest, the group has also prepared a "conceptual design" for a machine capable of applying the sealant to large areas with slopes of up to 30 degrees.

In addition to Ms. Schmitt, the following students are on the MIT team: freshmen Eric Gravengaard and Reginald Paulding; sophomore Stephanie Sparvero of CEE; juniors Melinda Moss and Maish Richard, both of CEE; seniors Kerry Bowie of CEE and Mike Strong of mechanical engineering; and graduate student Greg Diggs of ocean engineering. Ms. Schmitt, Mr. Bowie, Ms. Sparvero, and Mr. Gravengaard will represent the team in New Mexico.

The MIT Department of Civil and Environmental Engineering is fully funding the MIT team. WERC is a "consortium of universities, industries and national laboratories that provides resources to address issues of waste management and environmental remediation," according to a consortium release.

A version of this
article appeared in the
April 6, 1994

issue of MIT Tech Talk (Volume
38, Number

Topics: Contests and academic competitions, Environment and energy

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