In water treatment, one part per million is 8.34 pounds in a million gallons in that one gallon weighs 8.34 pounds. A package plant is particular method of sewage treatment, which involves the use of return activated sludge that is able to reduce BOD in a matter of hours. Package plants are usually used for small communities and not do use forced air like an extended aeration plant. Packaged plants are very economical to operate, but produce a large amount of sludge and have poor ammonia removal. Piping allows conveyance of a fluid from one point to another.
Precision refers to the consistency in grouping of results in measurement.
The amount of rain, snow, hail, etc., that has fallen at a given place within a given period, usually expressed in inches or centimeters of water. Pumps are mechanical devices that change pressure at a given flow. Pumps are most efficient at only one pressure and flow and are rated accordingly. Standards and procedures set by the administrative branch of the government to enforce laws and treaties that protect the environment. For example, the Environmental Protection Agency and the Clean Water Act establishes limits on pollution from private and public sources.