ABSTRACT
Millions of wells have been constructed in the Industrialized World, mostly since the early 1980s, for a purpose other than the traditional ones: groundwater supply, recharge, or dewatering. Among these other purposes are monitoring groundwater quality and pumping to control or clean up contaminated groundwater. Improvements in execution have come from experience in the "field" and from training of drillers and supervisory people. Manuals on monitoring well construction and design, not to mention improved methods, tools and equipment, and personnel skills, are part of the maturing of the industry. As the industry gains experience with long-term monitoring and remediation systems, however, well maintenance does become more of an issue. Relatively well-designed and carefully constructed systems are still failing to perform up to expectations, and are experiencing a variety of symptoms. Symptoms of well deterioration experienced in monitoring wells are most likely to include changes in physicochemical water quality and increased turbidity.
