The federal government is reviewing a proposal that could make Arizona the first state in the country to impose lifetime limits on Medicaid enrollment.

Arizona’s application for changes to its $12 billion Medicaid program includes system reforms aimed to increase efficiency, stepped-up wellness and prevention incentives and expanded private-sector partnerships.

The state received a letter from the federal government on Wednesday confirming that its application is under review.

Among the Arizona proposal’s controversial measures are imposing co-payments and premiums on certain enrollees, eliminating non-emergency transportation coverage for enrollees who earn more than the federal poverty level and imposing a five-year lifetime enrollment limit on “able-bodied” Arizonans who aren’t working, looking for work, in school or job training. Critics say such measures are punitive to the poor.

The requested overhaul of the program, which requires federal approval, is a combination of changes sought by both Gov. Doug Ducey and the Legislature. A federal decision is expected by Oct. 1, 2016.

Ducey and other supporters of the plan describe the reforms as a much-needed way for Arizonans to take more responsibility for their own health care and ensure Medicaid is a temporary option rather than a permanent solution.

The application submitted to the U.S. Centers for Medicare and Medicaid Services (CMS) includes 138 public comments. Most of them were critical of some changes, saying they had the potential to put up barriers to health care for the disadvantaged.

Some commenters, including the Arizona Hospital and Healthcare Association, said that while they have concerns about some provisions, the overall idea of modernizing Medicaid is a good one.

The state’s Medicaid program, called the Arizona Health Care Cost Containment System (AHCCCS), is for low-income residents. The threshold is a yearly income of 133 percent of the federal poverty level or less — that’s $32,253 or less for a family of four and $15,654 or less for an individual.

No other state has ever been approved to implement time limits in the Medicaid program, said Matt Salo, executive director of the National Association of Medicaid Directors.

The closest any state has come to doing so is a pending application the state of Michigan has with CMS, Kaiser Family Foundation Medicaid expert MaryBeth Musumeci says. The Michigan proposal would give enrollees the choice of increased Medicaid cost-sharing or private coverage via the federal health-insurance exchange after 48 months on Medicaid.

U.S. Rep. Raúl Gríjalva, a Democrat from Tucson, sent a letter to CMS on Oct. 8 urging it to reject Arizona’s application based on what he called “woefully insufficient” efforts by the state to inform residents of the proposed changes.

The state held a tribal consultation plus five public forums, including one in Tucson that was held at Casino del Sol, 5655 W. Valencia Road on the Pascua Yaqui Reservation during the Sun Tran bus strike. The state also accepted public comments by mail and email through an extended deadline of Oct. 12.

The public outreach exceeded federal requirements, said AHCCCS spokeswoman Monica Coury.

“As I am sure you know, we are the state Medicaid agency and there are things outside of our purview, like the bus,” she wrote in an email.

“In addition, the Tucson location was not far away for members of the Pascua Yaqui tribe, who routinely have to drive in to other parts of Tucson to attend such forums.

“It is also important to note that the Pascua Yaqui tribe graciously hosted us for that forum and did not charge us for use of their venue.”

The Tucson forum elicited an overwhelmingly negative response from the 100 or so people who attended.

Critics pointed to the provision in the overhaul that AHCCCS enrollees who earn more than the federal poverty level ($11,770 per year for an individual) and fail to pay their co-pays and premiums would be disenrolled from the program for six months.

They argued that those people would face a federal penalty for not having health insurance, which would only worsen their financial situation.

More than one-quarter of all Arizona residents are now enrolled in AHCCCS, with 1.8 million enrollees, including 280,284 in Pima County.