Object E-3 Sapfir (Dedurovka)

Object E-3 "Sapfir" is the site of a peaceful underground nuclear explosion at the Orenburg gas condensate field, in the Orenburg District of Orenburg Oblast, near the village of Dedurovka. The 1973 blast created an underground cavity that was then used to store gas condensate, making it one of the places in the region where gas storage was made with a nuclear explosion.

History

In the 1960s and 1970s the Soviet Union ran a programme of nuclear explosions for peaceful purposes: they were used to put out burning wells, stimulate production and create underground cavities in rock salt. The Orenburg field became one of the main sites for this work. The first cavity here, E-1, was made in 1970 by the "Magistral" explosion, 2.3 kilotons at a depth of 702 metres. Cavities E-2 and E-3 followed nearby.

The E-3 explosion took place on 30 September 1973 with a yield of 10 kilotons. Its purpose was practical: an underground reservoir for the liquid gas condensate produced together with the gas.

How the storage worked

In 1974 cavities E-2 and E-3 were connected to the Orenburg gas condensate complex, which produced about 50 billion cubic metres of gas a year. The working pressure in the storage cavities ranged from 80 to 140 atmospheres. Storing and settling the condensate underground made it possible to move it without pumps, using the reservoir pressure of the associated gases.

Cavity E-3 was taken out of service at the end of 1995.

The site today

Today it is a closed industrial site, not a museum. Next to the cavities there is a near-surface storage facility for solid radioactive waste left over from the work. The condition of cavities E-1, E-2 and E-3 and of the waste store is checked from time to time through engineering surveys.

Good to know

The nearest settlement is the village of Dedurovka, reached by bus from Orenburg. The site belongs to the gas field operator and is not an abandoned place to explore: do not go past the fences or take anything away from it.