GUEST VIEW: New scientific tool can help stop acid rain
March 26, 2015
Utica Observer Dispatch
By Charles Driscoll
Nobody likes acid rain. It kills fish and forests, contaminates the food chain with mercury, damages buildings and monuments, and degrades drinking water by leaching copper and lead from the plumbing in people’s homes. Its impact on clean water, public health and the economy is felt in North America, Europe and Asia.
Fighting acid rain has traditionally required public officials to make a judgment call about how much air pollution to cut and from which sources, based on estimates of what those cuts would cost in dollars. We had much more trouble predicting the precise environmental benefits of those cuts, or how much it would cost to stop acid rain damage entirely.
Thanks to recent research conducted in New York, scientists have a new method for predicting what level of air pollution cuts will be enough to protect every forest, every lake and all wildlife in a given region of the country.
In essence, we can establish a threshold, or “critical load,” for air pollution. Below that level, air pollution does no measurable harm to the environment, according to current scientific knowledge. Above that level, it does.
We can now state with some confidence that we know how many pounds-per-acre of air pollution can fall before the trees in a maple forest begin to decline, or before a shallow pond in a small drainage basin starts to lose its fish. While those two critical loads may be different, a single standard can be set that would protect both maple forests and fish.
New York’s Adirondack Park – the largest park in the contiguous United States — has suffered some of the worst acid rain damage in the nation. It is also a living laboratory for acid rain research. The park is downwind of the Midwest’s coal-fired power plants and industries. Automobile traffic, heavy machinery and agriculture add to the problem. The park’s steep slopes and thin soils do little to neutralize acidic rain, snow, fog and dry particles.
Recent reductions in air pollution brought on by the federal Clean Air Act have reduced sulfur- and nitrogen-based air pollution significantly since 1990. Progress has been possible because of bipartisan, science-based steps taken at the state and federal levels. But decades of continuous pollution damage will not heal overnight.
Some lakes and rivers are less acidic than a decade ago, but not all have improved. Meanwhile, soil acidification has continued. So acid rain is still damaging the park’s most sensitive areas.
Current emissions controls will be insufficient to allow a full recovery from the damage of acid rain. However, there is help in sight including several emerging opportunities to finish the fight against acid rain.
The U.S. Supreme Court’s recent decision to reinstate the Cross-State Air Pollution Rule was very encouraging. When combined with the pending Mercury and Air Toxics Standard, the two are expected to result in cuts of 42 percent below current emissions within a few years. This will bring substantial public health benefits from reduced smog and soot, as well as reductions in acid rain.
Even with those cuts, recovery will still take decades to centuries for significant parts of the Adirondack Park. Not every ecosystem will recover without additional help.
In the months ahead, the U.S. Environmental Protection Agency will be considering new air pollution standards to curb climate change (Clean Power Plan) and avoid damage to clean water and natural areas (Secondary National Ambient Air Quality Standard). These efforts will present an opportunity to employ the critical loads tool.
Last October, about 60 scientists, advocates and policymakers discussed the need to adopt a state critical loads standard during a conference in Saratoga Springs, where I delivered a white paper entitled “Acid Rain in the Adirondacks: A Road Map to Recovery.” The event was sponsored by the Adirondack Council and the Environmental Defense Fund, with funding from the Kirby Foundation. Senior representatives from the U.S. Environmental Protection Agency, and key state agencies, major universities and other scientific institutions participated.
State policy makers now have sufficient information to adopt and enforce a science-based critical load for the Adirondack Park. If New York can lead the way, as it has all along in the fight against acid rain, the next logical move would be for federal policymakers to adopt a standard that protects natural resources from acid rain across the Northeast and the nation.
Once we demonstrate that it works, the same method can be employed around the world to bring acid rain under control in an efficient and cost-effective way.