Ever-Fresh pump oil additive from Chempace Corporation is designed to eliminate offensive odors at their source. Mix 2 ounces of the additive into 1 gallon of pump oil. As the pump operates, a fresh fragrance will be emitted instead of offensive odors associated with portable restroom waste. The oil-based formulation will not change the viscosity of the oil. It is available in wild cherry, citrus or fresh cotton fragrances. 419/535-0101; www.chempace.com.