Cold Milling

A series of controlled flow and pressure measurements performed on a newly drilled or existing well to evaluate its production potential and reservoir characteristics; for subcontractors, this work often involves deploying and operating specialised equipment such as separators, flowback units, and data acquisition systems under tightly scheduled, high-priority conditions.

The process of pumping produced water or other fluid waste deep into underground formations for disposal. Subcontractors operating injection pumps or wellbore equipment must meet strict provincial and federal disposal regulations. Work often requires specialised well integrity certifications and detailed fluid volume reporting.

A safety and compliance management system used by some operators to pre-qualify and manage contractors working on their sites.

Operations performed on an existing well to restore, maintain, or improve production. Includes activities like recompletions, artificial lift installation, and remedial cementing.

A type of subsurface rock layer—primarily limestone or dolomite—that subcontractors may encounter during drilling, completions, or civil excavation work, often requiring specialised equipment, bit selections, or modified drilling programmes due to its hardness and tendency to cause lost circulation events.

The date when drilling begins on a new well. Marks the start of drilling operations.

What Is an AFE in Oil and Gas and How Does It Affect Subcontractor Payments?

An AFE (Authorization for Expenditure) controls every dollar spent on an oilfield project. Learn how it affects your billing, change orders, and cash flow as a subcontractor.