The La Hague plant, designed for reprocessing of fuel irradiated in the power reactors (GCR then PWR) is operated by COGEMA, which replaced the CEA as nuclear licensee under the terms of a decree of 9 August 1978. The plant is located on the north-western tip of the Cotentin peninsular, 6 km from cape La Hague and 20 km west of the town of Cherbourg. It covers a surface area of 220 hectares, on a plateau culminating at 180 m above sea level. It comprises an additional 80 hectares in Moulinets valley, down to the seashore. The COGEMA site adjoins the ANDRA site (Manche repository) to the east. The BNIs were installed on land made up of sedimentary rock (sandstone and shale) situated on a deep base of granite.

In 1959, the CEA decided to build reprocessing plant UP2 400, designed to reprocess spent fuel from gas cooled reactors. It became operational in January 1967 at the same time as the STE2, the role of which was to purify liquid effluent before discharge into the sea. In 1974, the CEA was authorised to modify the UP2 400 plant to allow reprocessing of PWR spent fuel. Finally, in 1981, COGEMA was authorised to build the UP2 800 plant (primarily for reprocessing French fuel), the UP3 plant (for reprocessing foreign fuel) and a new liquid effluent treatment plant, STE3.

The various facilities in the UP3, UP2 800 and STE3 were commissioned from 1986 (reception and interim storage of spent fuel) to 1994 (vitrification facility), with most of the process facilities becoming active in 1989/1990.

Under the terms of the decrees of 10 January 2003, the individual capacity of each of the two plants is 1000 t per year of initial metal (U or Pu), with the total capacity of the two plants being limited to 1700 t.

The COGEMA La Hague site thus houses the following installations:
- BNI 33 covering plant UP2 400, the first reprocessing unit, and AT1, a prototype installation currently being dismantled;
- BNI 38 covering effluent treatment station n° 2 (STE 2);
- BNI 47 covering the Élan II B facility, a CEA research facility currently being dismantled;
- BNI 80 covering the HAO facility, the first PWR fuel reprocessing unit;
- BNI 116 comprising the UP3 plant, initially intended for reprocessing foreign fuels;
- BNI 117 comprising the UP2 800 plant, initially intended for reprocessing French fuels;
- BNI 118 comprising effluent treatment station n° 3 (STE3).
Spent fuel reprocessing in the UP2-400 plant has now stopped. The production facilities in the UP2 400 plant have all been shut down.