(a) There shall be established and set up on the books of the commonwealth a fund to be known as the Health Safety Net Trust Fund, in this section and in sections 37 to 39, inclusive, called the fund, which shall be administered by the office. Expenditures from the fund shall not be subject to appropriation unless otherwise required by law. The purposes of the fund shall be: (i) to maintain a health care safety net by reimbursing hospitals and community health centers for a portion of the cost of reimbursable health services provided to low-income, uninsured or underinsured residents; and (ii) to support a portion of the costs of the Medicaid program under chapter 118E and the commonwealth care health insurance program under chapter 118H. The office shall administer the fund using such methods, policies, procedures, standards and criteria that it deems necessary for the proper and efficient operation of the fund and programs funded by it in a manner designed to distribute the fund resources as equitably as possible.

(b) The fund shall consist of all amounts paid by acute hospitals and surcharge payors under sections 37 and 38; all appropriations for the purpose of payments to acute hospitals or community health centers for health services provided to uninsured and underinsured residents; any transfers from the Commonwealth Care Trust Fund, established under section 2OOO of chapter 29; and all property and securities acquired by and through the use of monies belonging to the fund and all interest thereon. Amounts placed in the fund shall, except for amounts transferred to the Commonwealth Care Trust Fund, be expended by the office for payments to hospitals and community health centers for reimbursable health services provided to uninsured and underinsured residents of the commonwealth, consistent with the requirements of this section and section 39 and the regulations promulgated by the office; provided, however, that $6,000,000 shall be expended annually from the fund for demonstration projects that use case management and other methods to reduce the liability of the fund to acute hospitals; and provided further, that any amounts collected from surcharge payors in any year in excess of $160,000,000, adjusted to reflect applicable surcharge credits, shall be transferred to the General Fund to support a portion of the costs of the Medicaid and commonwealth care health insurance programs. Any annual balance remaining in the fund after these payments have been made shall be transferred to the Commonwealth Care Trust Fund. All interest earned on the amounts in the fund shall be deposited or retained in the fund. The director shall from time to time requisition from the fund amounts that he considers necessary to meet the current obligations of the office for the purposes of the fund and estimated obligations for a reasonable future period.