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with today's question, what is the Strategic Petroleum Reserve? The Strategic Petroleum Reserve is the United States is emergency oil stockpile, and it's the largest emergency petroleum supply in the world. The reserve stores about five hundred seventy million barrels of crude oil in underground salt caverns at four sites along
the Gulf of Mexico. A barrel contains forty two gallons or a hundred fifty nine liters of oil, so we're talking about more than twenty billion gallons of oil stored underground. To create the caverns, workers drill into a salt dome and then put water into the hold to dissolve the salt. Each cavern is about two thousand feet deep and holds
about ten million barrels of oil. The government uses salt caverns because it costs less than storing the oil in above ground tanks and because the pressure from the earth will seal up any leaks that might develop. The Energy Department also says that the temperature difference in the caverns, which are about two thousand feet below the surface of the earth, keeps the oil circulating so that the petroleum
maintains its quality. The government chose to put the oil near the Gulf of Mexico because there are so many oil refineries nearby and because shipping is readily available. It costs the federal government twenty one million dollars a year to maintain the oil reserve, and about people work for the oil reserve. About a hundred twenty five of those
are government employees and the rest are contractors. The United States started the petroleum Reserve in nineteen seventy five after oil supplies were cut off during the nineteen seventy three seventy four oil embargo. The embargo was a shock to the U s economy, and the government decided that the country should never be caught short again. The United States uses about twenty million barrels of oil every day, and
more than half of that oil comes from imports. A reserve of sixty days worth of petroleum could keep the oil flowing in case of a cut off. The last time that the United States used oil from the reserve was during the Persian Gulf War in n to keep oil plentiful and prices stable during that war. For more on this and thousands of other topics, because it how staff works dot com. Audible dot com is the leading provider of digital audio books and spoken word. With over
one tho titles to choose from. Audible lets you listen to your favorite books anywhere, anytime. Go to Audible podcast dot com slash stuff Brain to get a free audio book download of your choice when you sign up today.