Work halted on giant gas storage plant after minor earthquakes detected in area

The Industry and Energy Ministry has halted activity at the Castor offshore subterranean gas storage plant after some 200 minor earthquakes were detected last week around the area of Vinarós, on the Ebro Delta in the province of Castellón.

The EU-backed facility, Spain's largest, was due to open this summer, and has the capacity to store 50 days' worth of the country's natural gas needs. But for the last year many local residents, particularly fishermen in the Ebro River delta, have complained about the impact of the vast site, which is located immediately off the coastline.

Developed by Spain's ACS and Dundee Energy of Canada, Castor is not yet online, and is at the phase of injecting the so-called cushion gas needed to provide the pressurization to extract remaining gas from a storage facility.

In a statement on September 26, the Industry Ministry ordered the injections to be stopped, calling for a detailed report from the country's National Geographic Institute (IGN) on the seismic activity detected in the area.

The earthquakes have been low intensity, but affected around 75,000 people living along the coastline

Emilio Carreño, director of the IGN, said scientists were puzzled as to why the mini earthquakes were taking place so long after gas injections had stopped. The plant stopped injecting gas on September 16.

Carreño says the IGN had detected 220 mini earthquakes in less than a month, the strongest registering 3.6 on the Richter scale on September 24. He said that the seismic activity was taking place in an area that was normally calm.

The facility takes gas from the national grid for storage and pumps it back into the grid when it is needed, and is based on the geological structure of the old depleted Vinarós Castellon offshore oilfield. A 19-bank international consortium, five of which are Spanish, provided the $1.6 billion in financing. The site will be connected to the coast via a 13.6-mile-long offshore pipeline.

Spain has no hydrocarbons and imports more than 99 percent of its gas needs, making it Europe's largest importer of liquefied natural gas (LNG), accounting for almost a half of European imports.

Gas consumption is rising quickly. The Arab Spring has highlighted the strategic importance of the Castor project to provide reliable storage of LNG. Algeria is Spain's biggest supplier, making up around a third of imports. In an earlier bid to diversify supply, in 1998 the government passed legislation restricting any single country from supplying more than 60 percent of Spain's natural gas imports. Spain is also supplied by Nigeria, Qatar, and Trinidad and Tobago.

The earthquakes have been low intensity, but affected around 75,000 people living along the coastline between the towns of Alcanar in Tarragona, to Peñíscola in Castellón, as well as prompting criticism from environmental groups. The authorities in the town of Benicarló called on the industry ministry to halt the gas injections "until the seismic situation was under control."

Alcanar's fishing community also accuses Escal UGS, Castor's leading contractor, of damaging their nets and says that fishing boats cannot operate within a half-mile radius of the facilities. Escal UGS has paid some financial compensation to local fishermen, but they are still complaining about diminishing catches and are demanding a further 100,000 euros in compensation for damages.