If the Dakota Access Pipeline (输油管) is completed, it will carry nearlyhalf a million barrels of oil across four states every day. Energy Transfer Partners(ETP), a Texas-based company behind the $8 billion project, hopes to finishconstruction this year. But the Standing Rock Sioux, an American Indian tribe (部落), is determined to stop the 1,172-mile pipeline from being built. (79) Both sidesshow no signs of backing down. 

The Dakota Access Pipeline was announced in 2014. A section of it will runnear the Standing Rock Sioux reservation. A reservation is an area of land set asidefor American Indians. The tribe says the construction threatens to destroy historicalareas and ancient burial sites. They also say the pipeline could pollute their mainwater source, the Missouri River. In April, the Standing Rock Sioux began a protestagainst the project. They camped at the construction site. Since then, thousands ofpeople, including people from other American Indian tribes, have traveled to the siteto join the protest. 

ETP says that the pipeline will have built-in safety measures to protectagainst oil leaks. Workers will also monitor it remotely, and will be able to closevalves (阀) within three minutes if leaks are detected.