The operator of each such bulk tank hauling facility or route shall keep a detailed record of the quantity of milk received from each source and the quantity delivered to each destination. Such records shall be kept at a designated location for a period of at least three years, and shall be made available for examination or audit by any duly authorized representative of the commissioner. Such records shall include the full name and address of each producer from whom milk was received, his cooperative affiliation, if any, and such other records as the commissioner may deem necessary. The disposal of all samples to be tested for butterfat content shall also be thus recorded.