Drillers, sanitarians debate stainless-steel liners as in-place well rehabilitation

A contractor product that inserts and mechanically expands stainless-steel liner segments inside an existing well casing prompted detailed discussion about its suitability for permanent repairs and whether it meets well-code and NSF requirements.

At the meeting, staff described the product and played an illustrative video. Drillers and sanitarians raised concerns about whether an expanded stainless liner can form a complete annular seal, how the process performs where casings have pinholes or are already structurally compromised, and whether a rubber gasket or neoprene layer between casing and liner would meet NSF potable-water material requirements.

Staff said that, under current rules, many well-code requirements apply at initial construction and that liners installed after construction have distinct requirements; linings that become permanent casing must meet casing material standards. Participants said the product has mainly been used in larger municipal-style type 1 wells and that its economics may make it attractive for large, expensive wells but less applicable to typical residential wells.

Several attendees argued the technique may be acceptable as a temporary fix in constrained situations but warned that when casing shows multiple pinholes or is near failure, rehabilitation could be a higher-risk proposition than drilling a replacement well. No consensus was reached; staff said two avenues for regulatory review are (1) confirm NSF/NSF-equivalent material certification for components that contact drinking water and (2) consider whether liner installations should meet permanent-casing standards under the well code.

The group agreed to continue collecting technical documentation from the contractor and to ask EGLE engineering staff to review materials and determine whether the product can be permitted under existing liner rules or whether code language needs clarification.