Mr. Erik Milito - The House Committee on Natural Resources ...

ISOLATING POTENTIAL FLOW ZONES DURING WELL CONSTRUCTION 73
— fibrous cement systems that form a bridge across the thief zone.
C.3.8 Planning and Operations Considerations
<strong>The</strong> following outline summarizes, in general terms, the data requirements and steps involved to plan a well in which
lost circulation is a possibility.
a) Pre-well planning for all phases.
1) Drilling:
i) pore pressures and fracture gradients;
ii) fluid selection—NAF vs water based mud (WBM);
iii) optimizing flow properties;
iv) ECD control, annular pressure measurements;
v) controlled ROP and hole cleaning;
vi) caliper logs;
vii) lost circulation, near-wellbore stress, and ECD computer modeling;
viii) treatment plan to prevent or mitigate losses.
2) Running casing and liners:
i) swab and surge pressure modeling;
ii) insure the hole is clean and free of cuttings;
iii) reduced drilling fluid weight and rheology;
iv) casing hardware selection;
v) pre-treat the drilling fluids to reduce pressures;
vi) breaking circulation.
3) Cementing:
i) ECD modeling;
ii) ensure losses are cured before cementing;
iii) utilize good cementing practices
iv) cement slurry design;
v) LCM in the cement slurries;
vi) spacer considerations—flushes, spacer design (hydraulics);