Mercury can cause corrosion, alloying and embrittlement in some materials. This may result in a loss of strength and toughness, so it is critical that mercury-sensitive materials are not used where mercury is present.

Norsk Hydro found that a newly drilled well in its Ormen Lange project in the Norwegian Sea was unexpectedly producing mercury at about 10 times the level of other wells in the field.

Intetech worked in an integrated team, which included process chemists, mechanical engineers, rotating equipment experts and health and safety advisers. We established the locations of mercury throughout the facilities and identified where mercury-sensitive materials had been used. The review included the various stainless steels specified for the subsea completion, flowlines and platform processing facilities. Change-outs took place where unsuitable materials were identified so that the platform could continue to operate safely.