For the purposes of carrying out this chapter, the Director of Finance may authorize the withdrawal from the General Fund of an amount or amounts not to exceed the amount of the unsold bonds that have been authorized to be sold for the purpose of carrying out this chapter. Any amounts withdrawn shall be deposited in the fund. Any money made available under this section shall be returned to the General Fund, with interest at the rate earned by the money in the Pooled Money Investment Account during the time the money was withdrawn from the General Fund pursuant to this section, from money received from the sale of bonds for the purpose of carrying out this chapter.