The Powder River Basin (PRB) is the most important coal-producing region in the United States and has a rich and interesting history. The Powder River Basin is among the most resource-dense regions in the US, with extensive stores of coal, crude oil, natural gas, and other commodities perfect for pressure vessel fabrication . About 120 by 200 miles of area in width and length, respectively. Vessel Works For Private Clients The newly announced joint pressure vessel projects in