Water Quality Changes with Well Aging and Well Cleaning

摘要

We all know that all things age and decay, and this includes wells. Rather than being eternal and ageless, drilled wells resemble the service vehicles that work on them in that they experience aging in the form of corrosion and reduced hydraulic performance. They also resemble vehicles in that a program of regular maintenance prolongs a productive service life, and restoration is a viable way to keep a venerable performer working. A well's function is typically to provide water from an underground source, either for production or sampling. The aging mechanisms ― corrosion and clogging ― affect the quality of this produced water. Both corrosion of metals and encrusting mechanisms produce reactive products that change water quality. For example, corroded iron (ferric iron) attracts and holds reactive metals such as iron, manganese, arsenic, and aluminum, and releases alloyed metals such as nickel, copper, and chromium. It also reacts with and removes sulfides and oxygen from solution.