We in Portland have a large-scale agent in the global environment right here in Casco Bay, visible from the Eastern Prom Wilderness. At numerous places along the trail, beginning just past the sewage treatment plant, but especially in the 200 yard stretch between the beach and the ledges where the trail curves to the right (southwest) around Fort Allen Park, the trail offers excellent views of the Wyman Station, an oil-fired power plant on Cousins Island.
Built in 1958, this power plant can produce over 850 MW of electricity for households and businesses throughout New England. It's Maine's largest single source of electricity, and also the largest single source of air pollutants like nitrogen oxide and sulfur dioxide, a cause of acid rain. Because the plant is older than the federal Clean Air Act, it was allowed to avoid pollution-control upgrades for decades. In 2001, the plant's owners agreed to a cap-and-trade regulatory scheme: continued air pollution there is now offset by pollution reductions elsewhere.
Air pollution is only one aspect of Wyman's ecological complexity, though. Because it burns oil (a lot of it), this power plant is connected with incomprehensible complexity to the far corners of the world: from Houston to the tar sands in the Canadian tundra, from the presidential palace in Caracas to the Siberian wilderness, and millions of places in between. And by way of Wyman, all of those places are linked to every light switch and appliance in Maine.
For a really mind-bending perspective of the Wyman, though, consider the almost 400,000 tons of carbon dioxide that the plant generates each year (for context, it's important to mention that even that staggering amount of CO2 isn't nearly as much as Maine's motor vehicles produce). The connections and consequences of that fact are harder to perceive, but the hiker can try to imagine Casco Bay one meter higher than it is today: a circumstance likely within this century.
Next stop on the trail: the Petrochemical Prospect continues in Portland Harbor.
Previously: Introduction, Trailhead, and The Beach
Link: FPL Energy: Wyman 4 fact sheet