The proceeds of general obligation refunding bonds shall either be immediately applied to the retirement of the indebtedness being refunded or be placed in escrow in any state or national bank within this state which is a member of the federal deposit insurance corporation and which has trust powers to be applied to the payment of the indebtedness being refunded upon presentation therefor; but, to the extent any incidental expenses have been capitalized, such refunding bond proceeds may be used to defray such expenses, and any accrued interest on the refunding bonds may be applied to the payment of the interest thereon and the principal thereof, or both interest and principal, or may be deposited in a reserve therefor, as the board may determine. Any such escrow shall not necessarily be limited to proceeds of refunding bonds but may include other moneys available for its purpose. Any proceeds in escrow, pending such use, may be invested or reinvested in securities meeting the investment requirements established in part 6 of article 75 of title 24, C.R.S. Such proceeds and investments in escrow, together with any interest to be derived from any such investment, shall be in an amount at all times sufficient as to principal, interest, any prior redemption premium due, and any charges of the escrow agent payable therefrom to pay the indebtedness being refunded as the same becomes due at their respective maturities or due at any designated prior redemption dates in connection with which the board shall exercise a prior redemption option. Any purchaser of any refunding bond issued under this part 13 shall in no manner be responsible for the application of the proceeds thereof by the special district or any of its officers, agents, or employees.