Regulatory Citation(s): 

 

78.83. Surface and coal protective casing and cementing procedures.

 

(c) The operator shall drill to approximately 50 feet below the deepest fresh groundwater or at least 50 feet into consolidated rock, whichever is deeper, and immediately set and permanently cement a string of surface casing to that depth.  Except as provided in subsection (f), the surface casing may not be set more than 200 feet below the deepest fresh groundwater except if necessary to set the casing in consolidated rock.

 

 

Question:

 

An operator planned to use a two-string (not including conductor) well design with a surface string more than 200 feet below the deepest fresh groundwater, but the new regulations require a surface casing set depth of no more than 200 feet beyond the deepest fresh groundwater formation, so they will change to a  three-string design (surface/intermediate/production). The operator must order new pipe to transition to a three-string design.  Regional technical staff indicate the Department may wish to be flexible in this situation, especially where operators have already set and cemented conductor pipe. The diameter of the conductor essentially dictates the number/O.D. of all inner strings. The alternative would be to have operators rip out all cemented conductor in order to reinstall larger conductor pipe.

 

 

Response:

 

It is acceptable to be flexible and allow the original well design only if the conductor pipe was cemented at the time the regulations were finalized.