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Four veteran groups and a prominent military association have joined forces to pressure Sen. Mike Lee (R-Utah) to drop his opposition to a “Blue Water Navy” bill, which would make tens of thousands of ailing veterans who served on ships that patrolled territorial waters off Vietnam during the war eligible for disability compensation and health care from the Department of Veterans Affairs.

These veterans contracted illnesses over the years that the VA lists as ailments presumed to be associated with exposure to Agent Orange and other herbicides sprayed ashore during the war to expose enemy ground forces.

The intensifying pressure on Lee, plus some last-minute compromises between veteran groups and the Senate Veterans' Affairs Committee, have resuscitated the Blue Water Navy Vietnam Veterans Act (HR 299), which last week seemed set to expire by mid-December with the lame duck Congress.

Suddenly, odds have risen that the Senate will pass a bill identical to the one approved unanimously by the House in June, despite stiffening opposition from the embattled Trump administration and VA Secretary Robert Wilkie.

Conn Carroll, Lee's communications director, said Wednesday afternoon that the senator remains “committed to giving science the time it needs to properly inform policy” on Blue Water veterans and the health effects of patrolling within 12 nautical miles of Vietnam during the war.

In the Senate, an individual lawmaker can put a hold on most any bill. Lee and another still-unnamed senator put a hold on Blue Water Navy legislation. Lee's office, when queried last week, confirmed his opposition, explaining that the senator from Utah wants action on the bill delayed until the Department of Veterans Affairs delivers a promised new health study on Vietnam veterans.

Wilkie had urged a delay when he told the Senate Veterans Affairs Committee in September to expect a study comparing ailments and morbidity of Vietnam vets, including a sample of shipboard personnel, with Americans of similar age. The study is to be completed sometime in 2019.

[RELATED: Blue Water Navy Vets Need Your Help -- Petition Congress Before Time Runs Out]

Blue Water Navy advocates, however, want no more delays. And Sen. Johnny Isakson (R-Ga.), chairman of the Senate committee, and Sen. Jon Tester (Mont.), its ranking Democrat, have promised to push through a bill this year, taking advantage of momentum behind the House vote.

On Wednesday evening five groups -- The American Legion, Disabled American Veterans, Veterans of Foreign Wars, Paralyzed Veterans of America and Military Officers Association of America -- sent a joint letter to Lee, requesting a meeting “no later than the end of next week” to “hear your concerns” on HR 299 and “present our views on the merits of this legislation.”

The letter notes that the groups combined have 5 million members, “including 19,000 who live in Utah,” and that HR 299 passed the House unanimously and “has been awaiting Senate approval for almost six months.”

Meanwhile, negotiations in recent days between Isakson, Tester and veteran service organizations reached key compromises and a consensus to back a Senate bill identical to the one passed by the House. This will avoid the need to send an amended bill back to the House for a final vote before the 115th Congress adjourns in mid-December.

This represents a concession by the largest veteran service organizations, who joined in recent months to oppose the House bill's method of funding Blue Water Navy benefits by increasing VA home loan funding fees including, for the first time, imposing fees on certain disabled veterans -- those who opt to use a new jumbo loan feature the bill approves for veterans to be able to buy homes in pricey areas of the country or buy larger-than-average homes anywhere.

To continue to shield disabled veterans from any new fees, Isakson had drafted an amendment to HR 299 that would extend for two years the period when higher fees are imposed on non-disabled veterans using the VA loan benefit. But veteran groups told Isakson they would endorse Senate passage of HR 299 without his amendment if he understood the need to remove the jumbo loan fees from disabled veterans at the first opportunity in the 116th Congress and find a more acceptable way to fund much of the Blue Water Navy bill.

[RELATED: VSOs Push Back Against Blue Water Navy Comments]

Isakson, in turn, agreed to drop support for another proposal to amend HR 299, this one from Sen. Bill Cassidy (R-La.), which would soften resistance of some Republicans who want Congress to make it harder for VA to expand the number of ailments presumed associated with battlefield toxins in wartime.

The Agent Orange Act of 1991 allows VA secretaries to adds ailments to VA's list of illnesses presumed caused by herbicide exposure if studies from the National Academy of Medicine confirm either a “sufficient” association or a “limited or suggestive” association between herbicide exposure and the disease.

Cassidy, who supports the Blue Water Navy bill, proposed eliminating the law's “limited or suggestive” language for adding ailments to VA lists of medical conditions presumed caused by Agent Orange or other toxins used in past or future wars. Ailments could still be added only if medical research found a “sufficient” association between a disease and veterans' exposure to contaminants.

Cassidy's call to stiffen standards would not have affected veterans currently receiving VA compensation and health care for a presumptive ailment, nor would it have narrowed current lists of presumptive ailments for Agent Orange or other toxins, for veterans filing new claims. An early version of last week's column had described his proposal incorrectly. He only sought to raise the threshold for the addition of new ailments to VA presumptive disease lists.

Veterans groups opposed the Cassidy proposal and, for now, it is shelved. The challenge now is to pass HR 299 with few days remaining in the 115th Congress. The quickest route is for Isakson to bring the House bill to the Senate floor and seek unanimous consent of colleagues to pass it expeditiously.

If no senator objects, the Senate permits the action. In this case, if Lee or the unnamed senator also with a hold on HR 299 walks to the floor and objects, the bill dies and Blue Water Navy veterans start their fight anew in the 116th Congress.

Lee's spokesman, Carroll, acknowledged that the senator received a request to meet with veteran groups. He said, “We are committed to making sure they know our concerns and we know theirs.”

Does Lee plan to block a unanimous consent vote on the bill?

“Undetermined,” said Carroll.

What about his commitment to give science the time it needs?

“There all multiple considerations made whenever a senator chooses to object to a unanimous consent request,” Carroll said.

A veteran group representative said Lee has been “carrying water” for the Trump White House in opposing the bill. Carroll objected to that characterization.

“Senator Lee carries water for no one,” he responded in an email. “I think he's deservedly earned his reputation as a principled thinker.”

For the next week and perhaps beyond, Lee's principles regarding Blue Water Navy veterans and their survivors will be under a lot of pressure.

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