Regulatory
Citation(s):
78.83b. Casing and cementing – lost circulation.
(a)
If cement used to permanently cement the surface or coal protective casing is
not circulated to the surface despite pumping a volume of cement equal to or
greater than 120% of the calculated annular space, the operator shall determine
the top of the cement, notify the Department, and meet one of the following
requirements as approved by the Department.
Question:
Section
78.83b.(a)(1) – (4) provides four specific casing
options in the event that lost circulation is encountered over the surface
casing interval. Are operators allowed
to select one method preliminarily but change to another method later? Can subtle variations of these methods be
implemented if deemed acceptable by the appropriate Regional contact and how
should these procedures be documented?
Response:
Operators
have the flexibility to deviate from their initial plan and select from any of
the other available options under the referenced section of the regulations provided
the rationale for doing so is deemed acceptable and the selected method does
not introduce any environmental or well integrity concerns associated with the
lost circulation zone or other site-specific conditions. The change in methods and Department approval
should be documented in all cases.
Other
reasonable and technically sound methods for addressing lost circulation may
also be implemented even if they vary from Section 78.83b.(a)(1)
– (4). However, they must be approved by
the appropriate Regional staff prior to implementation and should be documented
using the methods available under Section 78.75 either prior to or after
execution of the alternate casing and cementing procedure.