MADISON, — A new discovery promises to put old tires into action minimizing the harsh environmental impacts of chemicals and fertilizers used on golf courses while offering a more preferable playing surface for the seasoned pro.

Scientists at the University of Wisconsin-Madison say placing tire chips (from ground-up vehicle tires) beneath golfing greens can absorb harmful organic compounds and prevent the leaching of pollutants into the earth and groundwater. Often, the chemicals used to maintain the aesthetic look of a green are detrimental to the environment. Since many courses are close to groundwater or wetlands this can have seriously effects on their safety and quality, say the researchers.

"Tires have a good absorption capacity -- like a sponge," says Jim Park, professor of civil and environmental engineering at UW-Madison and leader of the study. "If this technique is widely applied it could reuse up to one to 2% of scrap tires [in the U.S.]."

The U.S. Environment Protection Agency has estimated that, in 2001, the country held 273 million scrap tires with only 33 million being reused.

According to scientists, around 1,000 pounds of pesticides are applied to a golf course annually -- with more than 23,000 courses in the US this is a considerable amount of potential pollution. Professor Park says that one of the main benefits of using tires in this way is that they can absorb nitrate. His experiments show that having a 10-centimeter layer of tire beneath a course for over a year reduced nitrate release from the turf by 60%.

Park estimates that an 18-hole golf course would require 40,000 tires to cushion the green. He recommends that the technique be used for a course that needs renovation or an improved drainage system. "Otherwise it is something which new courses can take advantage of -- especially greens which are going to be constructed in environmentally sensitive areas," says Park.

Some environmentalists have been concerned that toxic pollutants from tires may seep into the ground, which may counter any absorption benefits gained from the technique. "The main pollutant from tires is zinc," explained Park. "However, this is safeguarded against in the secondary drinking water standard in the U.S. -- which provides for aesthetic rather than health precautions -- and our research has shown that zinc levels from the tires are 100 times less than the nationally permitted rate," he said.

The process is, however, more expensive than the traditional peat gravel layer which is used to bed the greens. "The price of the tire is about three times more than peat gravel, but installation costs would be much cheaper because the load is lighter and easier to spread. We hope the costs would come down once the use becomes more widespread," said Park.