DETROIT | Lynn Henning's southern Michigan farm is within 10 miles of a dozen large livestock farms, and for years she has gathered water samples and used aerial photography to help hold them accountable to environmental laws.
With the growth of factory farming over the past decade around the small, rural communities of Clayton and Hudson, Mrs. Henning said government oversight has failed to keep pace. So in addition to being a full-time farmer, growing corn and soybeans with her husband, she's a full-time environmentalist.
"They don't have the funding or the staff to baby-sit these facilities and watch them around the clock," said Mrs. Henning, 52, who has worked as a factory-farm watchdog with the Sierra Club in Michigan since 2005.
On Monday, Mrs. Henning was honored in San Francisco with the Goldman Environmental Prize, an award for grass-roots activism that includes a $150,000 award. The prize is among six given to environmentalists throughout the world.
The Goldman jury said Mrs. Henning's work illustrates grass-roots efforts to police concentrated animal feeding operations, or CAFOs, which produce enormous amounts of manure and can threaten air and water quality.
The award comes at a time when environmentalists are trying to learn from each other. Their techniques include flyovers of North Carolina's Neuse River in search of pollution from big hog farms and a legal fight over a plan to open a massive dairy in Illinois near the Wisconsin state line; it would start with 5,500 cows.
Some agricultural groups maintain that owners of most big livestock farms are mindful of environmental responsibilities and are careful dealing with waste. Manure typically is stored in tanks or huge lagoons before being spread on farm fields.
Shane Ellis, a livestock economist at Iowa State University, said many big farms have made drastic improvements in how they manage waste and care for animals. He said the nation's food-distribution system, made up of a small number of large, powerful buyers, creates tight margins and a need for big livestock operations.
Without them, he said, food prices would be higher.
"They are concerned about what they do," Mr. Ellis said. "They want to be good stewards of the livestock and the land around them. It's a change in how people are viewing … those resources."