Regulatory Intelligence
If a disposal well has Class Ib approval, does the operator also need Class II listed?
Category:
Waste Classification
Research Basis
Archive Period
1994-2019
Records Reviewed
6
Primary Topics
Class Ib; Class II; brine equivalent; produced water; common oilfield waste; approval wording
Current Reference
AER Directive 051
Common Question
If a disposal well has Class Ib approval, does the operator also need Class II listed?
Archive Findings
The 2019 AER correspondence in the folder directly addresses the practical question. AER staff stated that a Class Ib disposal approval can dispose Class II fluids and that older approvals sometimes listed Class Ib and Class II, while newer wording may list only Class Ib because Class II is implied. The 1994 workshop explains the historical basis: the well classification system was expanded so Class Ib would capture specific common oilfield waste streams, while Class II would be limited to produced water and brine-equivalent fluids. The archive therefore supports the operational lesson, but also shows why staff asked for clarification: approval wording can look incomplete if the logic is not documented.
Engineering Insight
.png)
Need help with an application?
Our team can help you navigate regulatory requirements, prepare strong applications and avoid costly delays
587.880.2249
Do not assume a reviewer, field operator, or auditor will infer the same classification logic from a short approval condition. In applications and internal operating files, identify each fluid stream, its proposed class, and whether it is produced water, brine equivalent, common oilfield waste, or a Class Ia-type waste. If relying on a Class Ib approval to receive Class II fluids, retain the rationale in the approval file and confirm the approval conditions do not restrict the fluid list more narrowly.
Current Guidance
Current Directive 051 classifies injection and disposal wells based on fluid characteristics. It states that Class II wells are for produced water or brine-equivalent fluids, while Class Ia and Class Ib are waste fluid disposal wells. AER Bulletin 2026-10 also identifies proposed Directive 051 revisions related to high-water-content hydraulic-fracturing flowback and Class II disposal; that bulletin should be monitored, but draft changes were not treated here as current requirements.