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•underground mining dangers- fire, collapse, explosions, black lung
-other issues: land subsidence, acid mine drainage into surface and ground waters (reclamation required, doesn't always work), coal fires in underground mines may be either naturally caused or deliberately set.
-strip mining: more common, safer, cheaper more destructive
surface mining process in which the overlying layer of soil and rock is stripped off to reach the coal.
-bigger problem in arid and semiarid regions, water problems associated with mining, land is very sensitive. -The Exxon Valdez oil spill occurred in Prince William Sound, Alaska, on March 24, 1989, when Exxon Valdez, an oil tanker bound for Long Beach, California, struck Prince William Sound's Bligh Reef and spilled 260,000 to 750,000 barrels (41,000 to 119,000 m3) of crude oil over the next few days. The oil, originally extracted at the Prudhoe Bay oil field, eventually covered 1,300 miles (2,100 km) of coastline, and 11,000 square miles (28,000 km2) of ocean.
-On March 24, 1989, the supertanker ran aground on Bligh Reef South of Valdez in Prince William Sound, Alaska. Alaskan crude oil that had been delivered to Valdez through the Trans-Alaskan pipeline poured out of ruptured tanks of the vessel at about 20,000 barrels per hour. 250,000 barrels entered the sound. -Both the long-term and short-term effects of the oil spill have been studied. Immediate effects included the deaths of 100,000 to as many as 250,000 seabirds, at least 2,800 sea otters, approximately 12 river otters, 300 harbor seals, 247 bald eagles, and 22 orca whales, and an unknown number of salmon and herring. In 2003, fifteen years after the spill, a team from the University of North Carolina found that the remaining oil was lasting far longer than anticipated, which in turn had resulted in more long-term loss of many species than had been expected. The researchers found that at only a few parts per billion, polycyclic aromatic hydrocarbons caused a long-term increase in mortality rates. They reported that "species as diverse as sea otters, harlequin ducks and killer whales suffered large, long-term losses and that oiled mussel beds and other tidal shoreline habitats will take an estimated 30 years to recover
-The spill produced an environmental shock which resulted in the passage of the Oil Pollution Act of 1990. The oil was spilled into what is considered one of the most pristine and ecologically rich marine environments in the world. Led to the death of 13% of harbor seals, 28% of sea otters and 100,000-645,000 seabirds. -Also known as fracking, well-stimulation technique in which rock is fractured by a hydraulically pressurized liquid. Process of drilling and injecting fluid into the ground at a high pressure in order to fracture shale rocks to release natural gas inside. They are exempt from major environmental acts, such as the clean water act but also have a high chance of spills, and accidents.
-During the process, methane gas and toxic chemicals leach out from the system and contaminate nearby well water. The contaminated well water is used for drinking water for nearby cities/towns. Drinking contaminated water can cause sensory, respiratory, and neurological damage.
-Effects: groundwater contamination, air pollution, methane pollution, lots of water withdrawals, management of waste water ;
