The Brazilian Institute of the Environment and Renewable Natural Resources (IBAMA) has opened a public consultation on a draft Normative Instruction that will regulate the environmental conditions for the offshore use and maritime discharge of drilling fluids, cuttings, and cement slurries in offshore oil and gas well drilling and completion activities.
The proposal is intended to replace Normative Instruction No. 01/2018, whose effectiveness was suspended in March 2019. Since its issuance, IN No. 01/2018 had been subject to criticism, particularly because it prohibited the offshore disposal of reservoir-phase cuttings and fluids. These concerns led to the suspension of the rule, and since then the “Guidelines for the Use and Disposal of Drilling Fluids and Cuttings” have been applied on a transitional basis, as determined at the time by the IBAMA Presidency.
The new draft regulation includes, among others, the following relevant changes:
- Authorization for disposal of water-based fluids and definition of reservoir phase: The draft maintains the prohibition on offshore discharge of cuttings generated in reservoir phases of wells, but removes the prohibition for water-based fluids, taking into account logistical constraints reported by operators, and introduces an express regulatory definition of “reservoir phase.”
- Prohibition on paraffin use: The proposal prohibits the use of paraffins in drilling and completion fluid formulations.
- Changes to sampling and monitoring frequency for fluids and cuttings: The sampling and monitoring frequency is changed to daily, whenever such discharges occur, in order to ensure more representative analytical results.
- Use of gas chromatography/mass spectrometry to assess oil contamination: The draft provides for the use of these methodologies to assess oil contamination in residues, in light of technical limitations associated with the Reverse Phase Extraction test.
- Incentives for technologies and innovation: The draft establishes targets and reference parameters for the use of more efficient treatment systems (such as thermal desorption, thermos-mechanical, and microwave systems) and for barite with lower heavy metal content.
- Introduction of the Barite and Organic Base Stock Sampling and Traceability Plan (PlanARE): Operators will be required to submit a sampling and traceability plan under the Fluids Administrative Proceeding (PAF), subject to prior approval by IBAMA.
- Effective date: The period for the new regulation to enter into force has been extended from 30 days to six months after publication.
Considering the operational and environmental compliance impacts for offshore drilling and completion activities, potentially affected companies are advised to review the draft carefully and participate in the public consultation process by submitting contributions to support improvements to the final text.
The public consultation will receive public comments until March 8, 2026.
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