Abstract: A method and apparatus is provided for reducing the purge volume of a well during purging and sampling operations. In some system embodiments, the apparatus can be retrofitted to existing small diameter wells. A further embodiment provides a method and apparatus for using direct pneumatic pressure to purge and sample small diameter wells using a removable valve. This aspect of the invention allows a direct pneumatic pressure pump with a primary valve to be withdrawn through the top of the inside to the pump's pressure holding structure without removing a riser pipe or the system's fluid inlet structure. The invention allows fitting or retrofitting small diameter wells with valves for direct pneumatic pressure purging and sampling.

Abstract: A method and apparatus is provided for reducing the purge volume of a well during purging and sampling operations. In some system embodiments, the apparatus can be retrofitted to existing small diameter wells. A further embodiment provides a method and apparatus for using direct pneumatic pressure to purge and sample small diameter wells using a removable valve. This aspect of the invention allows a direct pneumatic pressure pump with a primary valve to be withdrawn through the top of the inside to the pump's pressure holding structure without removing a riser pipe or the system's fluid inlet structure. The invention allows fitting or retrofitting small diameter wells with valves for direct pneumatic pressure purging and sampling.