A U.S. missile defense system may be constructed in Maine. The Department of Defense announced this past Friday that it will conduct an "environmental impact study" on four possible East coast sites including the NAS Portsmouth SERE Training Area in Maine.

Members of Congress are worried about Iran and that country's future nuclear capabilities. Meanwhile defense officials say that the two missile defense systems on the West coast can defend the U.S. against possible missile attacks.

Three other prospective areas will also have impact studies done, they are Fort Drum, New York, Cap Ravenna Joint Training Center in Ohio, and Fort Custer Training Center in Michigan.

The Defense Department said it would take about two years to complete the environmental impact study. It would take about five years to build a third missile defense system at a cost of $3.5 billion.