The study said another 240,000 to 510,000 people who already are eligible but not yet enrolled are expected to join because of the federal law's individual mandate and a simplified enrollment process.The Obama administration is encouraging states to expand their Medicaid programs by offering more money. The federal government will pay all medical costs for newly eligible enrollees for the first three years, with funding decreasing to 90 percent by 2020. The state would continue to be reimbursed at 50 percent for everyone else. State Health and Human Services Secretary Diana Dooley says the governor's budget proposes to include some funding for Medi-Cal expansion in the first half of 2014, but said true costs are not known. "I think there are as many estimates as there are estimators," she said. The expansion is projected to cost California $6.3 billion over 10 years, but that would be just 1.7 percent more than what the state would spend on MediCal without the expansion, according to the Kaiser Family Foundation. Dooley said she is concerned that the federal government has not finalized rules for reimbursing states to determine who is a newly eligible Medi-Cal recipient. It's not clear what medical benefits will be required under the expansion. And even though Medicaid was exempted from across-the-board cuts that threatened to push the nation over the "fiscal cliff," Dooley said it is possible Medicaid spending could be reduced in the next round of deficit talks. With so many unanswered questions, Brown has proposed two options for sharing some of the cost with California's 58 counties. One option would be to expand the state Medi-Cal program and ask counties to take on more responsibility for providing social services, such as child care. The other asks each county to run its own expansion program because many of them already have begun increasing coverage in anticipation of the health care reform law.