This paper will summarize the activities undertaken by the Thunder Horse Sub-sea Team in the
maintenance of the hydrotest-fill fluids for the sub-sea production flow-line/equipment from initial fill
Discussed will be:
• The initial fill of the Thunder Horse sub-sea system with chemically treated water and how this
treatment aligned with BP and MMS/EPA requirements.
• The position that the project team took as related to the continued effectiveness of the chemically
treated fill fluids, particularly with respect to the degradation of the biocide product (THPS) and
its ability to mitigate the effects of microbial influenced corrosion (MIC), over extended periods
leading to production start-up.
• The activities performed by the Thunder Horse project team to maintain the recommended
chemical concentrations in the sub-sea system during construction activities.
Key Words: Hydrotest, THPS, MIC