A new Senate bill aimed at reforming the scandal-ridden Department of Veterans Affairs immediately disappointed key lawmakers and veterans groups, who said Thursday that language on how to fire officials was "extraordinarily weak" and full of "loopholes."

Senators have been negotiating a broad reform bill for weeks. But there were suspicions from the start that they would water down a House-passed bill that set up strict timelines on how the VA can get rid of corrupt or negligent employees.

Sens. Johnny Isakson, R-Ga., and Richard Blumenthal, D-Conn., introduced their bill on Thursday, which confirmed those suspicions for many.

"The accountability provisions in the Senate omnibus bill covering non-senior executives, 99.9 percent of all VA employees, are extraordinarily weak," a House Republican aide told the Washington Examiner. "Instead of streamlining the removal process for employees, the provisions only make miniscule changes to the existing laws that are currently preventing VA from firing corrupt and incompetent employees."

Concerned Veterans for America also said the attempted accountability language doesn't go far enough.

"The VA is still plagued by almost-daily stories of misconduct, and unfortunately the accountability portion of the Veterans First Act leaves in place too many loopholes that could be exploited to delay or block adverse actions against employees guilty of such misconduct," said Dan Caldwell, CVA's vice president for legislative and political action.

Those pushing for tough reforms championed a bill from House Veterans' Affairs Committee Chairman Jeff Miller, R-Fla., which passed the House last year. That bill set up a fast procedure for firing or demoting any VA worker at will.

It was prompted by near constant complaining from Republicans and Democrats that the VA wasn't doing much to use a new law to fire senior VA workers involved in the healthcare scandal or several other scandals.

But the Senate proposal cuts back on the more aggressive House bill.

One key difference involves how long the VA would have to fire or demote workers. The House bill contains time limits at every stage, but the new Senate bill includes some open-ended language, which could allow the VA to take as much time as it wants.

For example, the Senate bill says the VA must give "at least 10 business days written notice" that a disciplinary action is being handed down. But the words "at least" indicate that the VA might be able to provide a notice, and then wait indefinitely before moving on to the next step.

In contrast, the House bill doesn't require any advanced notice.

The Senate bill gives the VA secretary an unspecified amount of time to review each case, which some fear could let the VA review decisions endlessly without making a final decision. It also says the secretary must review cases "as soon as practicable," which is another unspecified amount of time.

The House bill is much more definitive, and is aimed at getting the VA to finally make decisions to fire officials accused of manipulating veteran wait-times, retaliating against whistleblowers or multi-million cost overruns.

The House bill, for instance, gives employees just five days to respond to disciplinary proposals, and just seven days to appeal those decisions. Appeals are capped at 45 days.

The House GOP aide said the Senate bill also includes weaker protection for whistleblowers who say they have faced retaliation.

While the bill is nearly 400 pages long and covers a wide range of issues to deal with the scandal-plagued agency, the ability to quickly fire uncooperative employees has become one of the top reform issues at the VA.

In 2014, Congress passed legislation giving the VA the option to fire senior officials. But the VA hasn't moved aggressively to use the law, and has made about a dozen efforts to get rid of these employees.

Only three have been fired for reasons related to their role in the VA healthcare scandal, even though hundreds of employees were thought to be implicated by what investigators have called a "systemic" problem across the country.

The GOP aide indicated that House lawmakers would work to strengthen the law once they start negotiating a final bill with the Senate.

"Going to conference committee negotiations means the House will not vote on what the Senate passes until changes to the bill are negotiated with the House," he said.