PERMFILE60840

• Permit No: M1999002
• IBM Index Class Name: Permit File
• Doc Date: 6/18/1999
• Doc Name: OBJECTORS EXHIBITS
• Media Type: D
• Archive: No

(I) the internal body wear on the casing string due to drill pipe rotation or cable movement during
subsequent drilling operations, especially in deviated or crooked wells;
(m) the temporary or permanent nature of the casing installation; and
(n) the plugging requirements of Part 11 and the method of plugging the well.
3.5.1. Casing Removal
An operator shall not pull or strip a string of casing from a well, except where:
(a) provision is made for the removal of casing in the drilling program specified in the welt licence
application;
(b) casing is pulled and reset in the same formation to obtain a satisfactory casing seat;
(c) a well is plugged back or plugged to surface; and
(d) the annular space left open and the formation exposed by the pulling and stripping of casing is
sealed.
3.5.1.1. Casing Removal -Producing Wells
Where a well is a producing well, the operator shall ensure that:
(a) strings of casing intermediate between the producing casing and the surface casing are not
recovered unless all horizons containing oil, gas or water are cemented off,. and
(b) the surface casing is not recovered.
3.5.2. Minimum Hole Size
For the purposes of proper sealing of a well, the minimum hole size for a given casing shall be as
follows:
Casing Size (O.D. mm)
Up to 177.8 O.D.
Greater than 177.8 O.D.
Greater than 273.05 O.D.
Minimum Hole Size (mm)
Cable Tool Drilled Wells
Casing O.D. + 16
Casing O.D. + 33
N/A
Minimum Hole Size (mm)
Rotary Drilled Wells
Casing O.D. + 38.1
Casing O.D. + 50.8
Casing O.D. + 76.2
3.5.3. Minimum Annular Clearance
The operator shall design all well casing such that annular clearance between casings is not less
than 12 mm for cable tool drilled welts and 25 mm for rotary drilled wells measured from the I.D. of
the outer casing to the O.D. of the inner casing as shown in the following schematic:
Rotary
10
Cable Tool