The need to neutralize, or at least place limits on, the pH variation of environmental waters has resulted in the promulgation of water quality standards legislation in virtually every state. Wastewater treatment facilities must counter the hydrogen or hydroxyl ion imbalance in a waste effluent by adding a material that restores the ion balance. Chemical lime is produced by the calcination of high-quality limestone which produces either high-calcium quicklime or dolomitic quicklime. Limestone is an effective means of neutralizing waste acids. The process involves flowing the waste acids through a bed of limestone granules. The use of sodium hydroxide (caustic) is about equal to lime as a neutralizing agent. Researchers evaluated the reactivities of various basic reagents on the same chemical system by mixing them with pickle liquor. Ammonia is widely used in the petroleum industry where it is added to crude oil to neutralize acid constituents.