<P> Trump proposed in a White House meeting that the wall should be covered with solar panels, claiming that this would generate revenue and improve its appearance . On June 21, 2017, Trump told a rally in Cedar Rapids Iowa that he is working on ways "Mexico will have to pay much less money", saying that the wall would be a "solar wall" that could "create energy and pay for itself". Trump also touted a report he had seen on Fox News that cited a study by the Center for Immigration Studies, in which it claimed that a wall along the Mexican border could save taxpayers $64 billion by reducing crime and welfare costs for undocumented immigrants over the next 10 years . Some dispute this, claiming the wall and maintenance would cost more than predicted and that illegal immigrants would just find another way into the nation . In August 2017, while speaking at a rally in Phoenix, Arizona, Trump stated he will close down the U.S. government if necessary to force Congress to pay for the wall . As of the end of 2017, Mexico has not entered into any agreement to pay for any amount of the wall . In March, 2018, Congress appropriated $1.6 billion out of a $1.3 trillion spending bill, which helped toward adding and repairing fence along the border . </P> <P> On September 12, 2017, the United States Department of Homeland Security issued a notice Acting Secretary of Homeland Security Elaine Duke would be waiving "certain laws, regulations and other legal requirements" to begin construction of the new wall near Calexico, California . The waiver allows the Department of Homeland Security to bypass the National Environmental Policy Act, the Endangered Species Act, the Clean Water Act, the Clean Air Act, the National Historic Preservation Act, the Migratory Bird Treaty Act, the Migratory Bird Conservation Act, the Archaeological Resources Protection Act, the Safe Drinking Water Act, the Noise Control Act, the Solid Waste Disposal Act, the Antiquities Act, the Federal Land Policy and Management Act, the Administrative Procedure Act, the Native American Graves Protection and Repatriation Act, and the American Indian Religious Freedom Act . </P> <P> In September 2017, the U.S. government announced the start of construction of eight prototype barriers made from concrete and other materials . On June 3, 2018 the San Diego section of the US border wall construction began . </P> <P> Tribal lands of three indigenous nations would be divided by a proposed border fence . </P>

When was the wall in san diego built
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