67.738.  Trust fund, distribution of proceeds — additional duties of director of revenue — refunds authorized. — 1.  All sales taxes collected by the director of revenue under sections 67.730 to 67.739 on behalf of any county, less one percent for the cost of collection, which shall be deposited in the state's general revenue fund after payment of premiums for surety bonds as provided in section 32.087, shall be deposited with the state treasurer in a special trust fund, which is hereby created, to be known as the "County Capital Improvement Bond Sales Tax Trust Fund".  The moneys in the county capital improvement bond sales tax trust fund shall not be deemed to be state funds and shall not be commingled with any funds of the state.  The director of revenue shall keep accurate records of the amount of money in the trust fund which was collected in each county imposing a sales tax under sections 67.730 to 67.739, and the records shall be open to the inspection of officers of each county and the general public.  Not later than the tenth day of each month the director of revenue shall distribute all moneys deposited in the trust fund during the preceding month by distributing to the county treasurer, or such other officer as may be designated by the county ordinance or order, of each county imposing the tax authorized by sections 67.730 to 67.739, the sum, as certified by the director of revenue, due the county.

  2.  The director of revenue may authorize the state treasurer to make refund from the amounts in the trust fund and credited to any county for erroneous payments and overpayments made, and may redeem dishonored checks and drafts deposited to the credit of such counties.  If any county repeals the tax authorized by sections 67.730 to 67.739, the county shall notify the director of revenue of the action at least ninety days prior to the effective date of the repeal or expiration and the director of revenue may order retention in the trust fund, for a period of one year, of two percent of the amount collected after receipt of such notice to cover possible refunds or overpayment of such tax and to redeem dishonored checks and drafts deposited to the credit of such accounts.  After one year has elapsed after the effective date of repeal or expiration of the tax authorized by sections 67.730 to 67.739 in such county, the director of revenue shall remit the balance in the account to the county and close the account of that county.  The director of revenue shall notify each county of each instance of any amount refunded or any check redeemed from receipts due the county.