Method and apparatus for monitoring offshore contamination

Apparatus for determining whether a source of seawater contamination is from an offshore hydrocarbon well facility or whether the source of the contamination is external to the offshore hydrocarbon well facility, said apparatus comprising a plurality of removably attached sensor units each attached at the protective cover of a wellhead of said offshore hydrocarbon well facility and each comprising a biological sensor and a data transmitter coupled by a data transmission line to a remote data analysis facility, said apparatus further comprising at said offshore hydrocarbon well facility a seawater velocity sensor, a seawater conductivity sensor and a temperature sensor also coupled by a data transmission line to said remote facility, said apparatus further comprising a computer arranged to analyze data from said data transmission line to determine indicia of seawater contamination at said well facility and of the seawater flow at said well facility, and thereby to provide a signal indicative of seawater contamination above a preselected limit, wherein the source of the seawater contamination may be determined to be from the offshore hydrocarbon well facility or external to the offshore hydrocarbon well facility based on the seawater flow.

A method of detecting seawater contamination from an offshore hydrocarbon well facility comprising a sea surface drilling or production platform connected to a seabed wellhead, wherein a first plurality of at least three submerged sensor units is arranged around said platform at a depth of 15 to 50 m and at a distance of 50 to 500 m and a second plurality of at least three sensor units is arranged at the seabed around said wellhead at a distance of 50 to 500 m, each said sensor unit comprising a biological sensor and a data transmitter, said well facility further comprising a submerged sediment trap, a seawater velocity sensor, a seawater conductivity sensor, a seawater temperature sensor, and a data receiver arranged to receive data from said transmitters, wherein the method comprises analyzing data from said receiver to determine indicia of seawater contamination at said well facility and of the seawater flow at said well facility;

• and providing a signal indicative of seawater contamination above a preselected limit deriving from said well facility.

Apparatus for detecting seawater contamination from an offshore hydrocarbon well facility comprising a sea surface drilling or production platform connected to a seabed wellhead, said apparatus comprising a first plurality of at least three submerged sensor units arranged around said platform at a depth of 15 to 50 m and at a distance of 50 to 500 m and a second plurality of at least three sensor units arranged at the seabed around said wellhead at a distance of 50 to 500 m, each said sensor unit comprising a biological sensor and a data transmitter, said apparatus further comprising a submerged sediment trap, a seawater velocity sensor, a seawater conductivity sensor, a seawater temperature sensor, and a data receiver arranged to receive data from said transmitters, said apparatus optionally and preferably further comprising a computer arranged to analyze data from said data receiver to determine indicia of seawater contamination at said well facility and of the seawater flow at said well facility and thereby to provide a signal indicative of seawater contamination above a preselected limit deriving from said well facility.