How is the fee computed on parts of a gallon of oil?
The amount of motor oil and similar lubricants subject to the solid waste excise tax should be totaled at the end of the reporting period. When the total results in a fractional gallon, the total should be rounded up to the nearest whole gallon when the fraction is one-half gallon or more and should be rounded down to the nearest whole gallon if the faction is less than one-half gallon. For example, if total motor oil sales in South Carolina for the month are1000.75 gallons, then the amount shown on Form ST-390 should be 1001 gallons. Remember, only whole gallons are to be reported on the ST-390.
