If such wheat, described in § 38-10-28, remains in farm storage for the duration of such pledge or mortgage, the promotional fee so paid at the time the loan was made shall be deemed a complete satisfaction of the promotional fee liability unless upon subsequent actual delivery of such wheat from farm storage in satisfaction of the pledge, or mortgage in the amount of one dollar or more, such underpayment being due solely for the necessity of estimating the quantity of wheat so placed in farm storage.
SDCL 38-10-31