Once the program was fully in place, the budget office said it expected that veterans "would ultimately seek additional care that would cost the federal government about $50 billion a year" double current spending.
The bills are Congress's response to a growing uproar over patients dying while awaiting VA treatment and mounting evidence that workers falsified or omitted appointment schedules to mask frequent, long delays. The resulting election-year firestorm forced VA Secretary Eric Shinseki to resign two weeks ago.
An audit released last week showed that more than 57,000 veterans have had to wait at least three months for initial appointments. An additional 64,000 veterans who asked for appointments over the past decade never got them.
The VA has confirmed that at least 35 veterans died while awaiting appointments at VA facilities in the Phoenix area, although officials say they can't say whether not getting VA treatment caused any of the deaths.
More than 8 million of the nation's 21 million veterans are now enrolled in VA health care although only about 6.5 million seek VA treatment every year. The CBO analysts said VA now covers about 30 percent, or an average $5,200, of those veterans' annual health care costs, excluding long-term care.
The Senate bill would open up VA health care to as many as 8 million veterans who now qualify for VA health care but have not enrolled, the budget office said. By making it easier to get outside care, the Senate bill and a companion measure in the House also would encourage veterans to seek VA coverage for a bigger portion of their health care, the report said.
Both bills would make it easier to fire or demote senior agency officials, and both would end bonuses to regional VA officials and other administrators based on meeting patient scheduling goals a practice investigators say led some officials to create phony waiting lists to "game" the system.
But the Senate bill also would devote at least $1 billion to leasing 26 facilities in 17 states and Puerto Rico for use as new VA hospitals or clinics and $500 more million for hiring more VA doctors and nurses. Declaring the long appointment waits an emergency, the Senate averted having to raise taxes or find spending cuts elsewhere to cover the bill's costs.
"By resorting to abusing the emergency escape clause, Washington is once again looking for the easy way out," said Maya MacGuineas, president of the Committee for a Responsible Federal Budget, a bipartisan policy group devoted to cutting federal deficits.
MacGuineas' group criticized the Senate's bill in a lengthy blog post after it passed, saying it would swell the government's debt by creating a new unfunded entitlement program bigger than Congress's expansion of Medicare in 2003 to cover prescription drugs.
"We can't just write a blank check and think it will solve these problems," said Sen. Jeff Sessions, R-Ala., one of three senators who voted against the bill. He said "veterans deserve better than that."
Sen. John McCain, R-Ariz., one of the bill's authors, lashed back, "If it is not an emergency that we have neglected the brave men and women who have served this country and keep us free, then I do not know what an emergency is."
Sen. Bernie Sanders, I-Vt., the chairman of the Senate Veterans' Affairs Committee, said the bill was expensive, but so were the wars that veterans have served in. Wars in Iraq and Afghanistan alone will have cost at least $3 trillion, he said.
"If we can spend that kind of money to go to war ... surely we can spend (less than) 1 percent of that amount to take care of the men and women who fought those wars," he said.
The CBO did not provide a complete cost estimate on the House bill, which includes no provisions for new hospitals or clinics or hiring more VA doctors and nurses.
Both measures would spend billions to provide outside care for veterans, although the House would require Congress to appropriate money for it each year.
House Veterans' Affairs Committee Chairman Jeff Miller, R-Fla., said Congress would have to cover the costs, but he didn't know where the money would come from.
"We'll have to find a way," he told reporters after the Senate bill passed. "It's not going to be cheap. We know it."
Miller also said there would be negotiations with the Senate over final legislation. "We're not just accepting the Senate bill," he said.
Sanders was optimistic that a quick deal could be reached. "I've worked with Jeff Miller. I think we can work things out," he said.
Associated Press writer Alan Fram contributed to this story.
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