Less than an hour's drive from the Ikla border station, Latvijas Gaze, Latvia's partially-privatized gas concern, operates its subordinate company, Gazes Kratuve, which pumps at least two million cubic meters of Russian land gas underground into natural storage tanks. In winter, the company supplies gas to Latvian, Lithuanian and Estonian consumers. Some of it goes back to Russia.
The total capacity of the Incukalns underground storage is four billion cubic meters with 2.1 billion cubic meters in active use. At the beginning of the 1950s, geologists discovered that the Latvian soil holds sand stone layers, which provides for easy gas storage. The natural gas storage is covered by a layer of clay, which holds the gas under the ground. Below there is a layer of stone, which forms a floor for the storage.
The director of Gazes Kratuve, Ziedonis Blumbergs, said there are at least eight similar underground structures in Latvia, but exploiting them is economically irrational at the moment because land gas consumption in the Baltic states has decreased considerably during the past couple of years.
The natural storage regime is more rational if the amounts of the gas pumped under the ground and the gas extracted are equal.
In order to avoid dangerous situations, the company has employed a Latvian anti-terrorism unit specialist. According to Blumbergs, there haven't been any substantial damages in the past 30 years. If an accident was to occur, the rescue team arrives by chopper from Harkov in two hours, in compliance with a contract.
The Incukalns underground warehouses mean that the gas is compressed in the porous sandstone. For that, 166 shafts have been drilled up to a depth of 700 meters, 93 of which act as entrances for the compressed gas. The rest monitor and regulate the whole structure.
"No one has ever been underground," said Blumbergs. " Therefore we don't even know what the whole storage looks like."
Ilmar Kaev, the development sector's director of Eesti Gaas, Estonia's gas company, said transporting gas from Incukalns costs more than purchasing the gas straight from the Vires pipe.
The storage and transit expenditure is added. Therefore it's more lucrative to purchase gas through the Varska measuring station.
Land gas is imported into Estonia through the measuring stations of Karksi, Varska and Narva. And when it chooses, Estonia can close the taps. For instance, on July 30, these three measuring stations were closed because Estonia had sufficient gas supplies.
Most of the gas Estonia imports comes through the Vires pipe network. The city of Tallinn and the Iru power station account for nearly half of the needs of the whole country.
The Loo measuring station in the vicinity of Tallinn directs two gas pipes towards the town and one to the Iru power station. This fall, Eesti Gaas will receive new devices to install a second pipe to the Iru power station.
(Reprinted from the Estonian daily Postimees.)