The bittersweet closure of an acid rain monitoring site

I called Joe Scudlark last week to talk about ospreys and we ended up talking about acid rain. The dots do connect.

Joe sits in an office that looks out over the Great Marsh and several osprey nests. He's assistant director of the School of Marine Science and Policy in the University of Delaware's College of Earth, Ocean and Environment in Lewes. When the ospreys return each spring for their nesting season, Joe takes note. Joe also takes note whenever it rains.

For the past 38 years, almost all of his career with the university, Joe has directed an acid rain monitoring project in conjunction with the federal Environmental Protection Agency. Acid rain and osprey have federal ties, but in opposite directions.

In 1977, when the acid rain monitoring project started inside a chain-link fenced section deep in a scrubby, forested area of Cape Henlopen State Park, there were few ospreys around, but plenty of acid rain.

"There were times back then when we measured the acidity of rain at a pH of 3. That's very acidic," said Scudlark. "About the same as lemon juice."

As a result, fish were dying in lakes and streams, trees were dying in national parks and forests, and statues in town and city parks were deteriorating due to a steady assault by acid washes falling from the sky. Nitrous oxides and sulfur dioxides that formed in the atmosphere from coal-fired power plant emissions combined with rain to make the weak but damaging acids.

At the same time, the eggs of ospreys and eagles grew weaker and weaker due to the birds' exposure to pesticides like DDT. Populations of those birds plummeted.

Then environmental outcry led to creation of the Environmental Protection Agency in 1970. DDT and other pesticides linked to environmental degradation were outlawed, and Congress passed the nation's first Clean Air Act.

Now, almost five decades later and as a result of effective federal regulation, eagle and osprey populations are thriving, and acid rain is nowhere near as serious a problem as it once was. "Acidity has dropped by at least 70 percent," said Scudlark. "The Clean Air Act and its important amendments in 1990 have been a huge success. By any standard, our air is cleaner."

Bittersweet funding loss

But that success is mixed with bittersweetness for Scudlark. "We lost our federal funding for the monitoring program last September. It had been coming to us through the National Oceanic and Atmospheric Administration. All the equipment we used to monitor weather conditions and the quality of the rainfall has been taken apart and hauled away. There were a lot of costs involved with personnel, shipping samples out to central labs. All that's done now. After 38 years, it's over."

The monitoring site inside Cape Henlopen State Park included sophisticated, solar-powered gauges that gathered rainfall and kept out impurities falling from trees or birds that could have tainted the samples. When the program was in full swing, there were 250 collection sites around the country.

"But this site in Lewes was one of only about a dozen around the U.S. that sampled on a greater frequency. Us, Penn State, Cornell and a few others collected samples daily and sent them out to Illinois for processing. The more sophisticated sampling allowed us to help the country determine the source of pollutants and take effective action."

When the program first started, the goal was to determine the distribution and severity of acid rain across the nation. Then it evolved into a program to determine whether federal regulations were making a positive and measurable impact.

Scudlark said big air-quality improvement came after Clean Air Act amendments passed by Congress in 1990 significantly decreased the permissible levels of pollutants that could be dumped into the air from leaded gasoline and from power plants.

"By 1996, the pH of the rain we were collecting improved to 4.4. The pH measurement is logarithmic, so an improvement from 3 to 4.4 is huge," said Scudlark. "And it wasn't accompanied by our lights going out, cars becoming unaffordable, or our electric rates soaring, as industry predicted would happen when it was fighting the regulations." The Lewes site was particularly significant because here on the eastern edge of the continent, the area is subject to all the pollution that carries out of the Midwest on the prevailing westerly winds. According to EPA information, of 116 power plants in the U.S. slated for emissions reductions by the 1990 amendments, 62 percent were located east of the Mississippi. "We're downwind of everything," said Scudlark. "That's why we were one of the nation's benchmark stations. But I guess everything comes to an end eventually."

The good news is that there are more ospreys for us to watch and, in so doing, know that our environment has improved. And, the environmental degradation from acid rain for so many decades is now being reversed. "That's the legacy," said Scudlark. "The regulations did make a difference. Congress listened to scientists, and it worked."