The Exxon Valdez ran aground in Alaska in 1989 and spilled ten million gallons of oil on the shore. How do you clean up that much oil from the seashore? At first, it was power washing, pushing the oil from the shoreline into the water so it could be scooped up easier. But the power washing itself was damaging the ecosystem, so the cleanup crews limited that procedure to some places, while leaving others alone. A car-sized boulder called Mearns Rock was left with oil on it. The rock was named after Alan Mearns of NOAA's hazmat team.
In the 33 years since the cleanup, Mearns Rock has been photographed every year, first by NOAA, and afterward by volunteers. The rock, exposed to oil, sun, rain, ocean water, and air, stands firmly in the same spot but plays host to different life forms year by year. Scientists and conservationists get an idea of which plants and animals recovered from the spill and how long they took to do it, and which species never returned. Read about the recovery from the Exxon Valdez spill and how Mearns Rock plays it part at Hakai magazine. -via Atlas Obscura
(Image credit: Alan Mearns/NOAA)