Loan terms shall include, but not be limited to, the following:

(1) The term of the loan shall not exceed thirty years, except for systems serving disadvantaged communities which term may not exceed forty years;

(2) The interest rate shall be at or below market interest rates;

(3) The annual principal and interest payment shall commence not later than one year after completion of any project; and

(4) The loan recipient shall immediately repay any loan when a grant has been received which covers costs provided for by such loan.