St Louis Airport Storage Site (SLAPS)

General Information

The Commission maintains a residue storage area known as the Airport Site at Robertson, Missouri. This site is located immediately north of the St. Louis Municipal Airport and east of the McDonnell Aircraft Corporation Plant on Brown Road in St. Louis County.

Consent to use and occupy the 21.7 acre tract was obtained by the Manhattan District on March 2, 1946. Title was acquired to the property on January 3, 1947 by condemnation proceedings for $20,000. It was aerquired for the purpose of storing residues from the Destrehan Street Refinery and the Metal Plant at Plant 4. A covered concrete storage pad 45′ x 250′ was constructed for storing drums. A concrete pit 202′ x 42′ x 16′ was constructed to store radium bearing residues (K-6). The area was enclosed with a chain-link fence. Later a small building containing showers, change room and office space was moved to the site. A railroad siding,and loading facilities were completed in April 1959. The site was operated by the Manhattan District and the Commission from 1946 until July 1953 when the operation was turned over to Mallinckrodt Chemical Works. Guards were maintained at the site from 1946 to 1951.

In the Metal Plant at Plant 4 and later in the new Metal Plant at Destrehan Street (6E), the slag from the reduction step was separated into two parts. The slag Immediately above the derby consisting mainly of MgF₂ was sent to the Vitro Corporation at Canonsburg, Pa., for uranium recovery. The remaining slag (C-Liner), consisting mainly of dolomite liner with less than 2% uranium content was stored at the site in bulk on the ground. These shipments started on March 10, 1946 and continued until early in 1953 when the dolomite liner was replaced by a recycle MgF₂ liner.

The Destrehan Refinery started up in 1946 and continued to use pitchblende ores as a feed until early in 1955. The contract to purchase these ores with African Metals Corporation required the U. S. to store the raffinate (AM-7), containing metallics such as nickel, cobalt, and copper, and radium bearing residues (K-65). African Metals retained ownership of all material except the uranium content. Although other concentrates were processed during the period, the raffinates were not separated. They were stored in bulk on the ground at the site. The pit constructed to store the radium bearing residue (K-65) was not used due to health reasons. This residue (K-65) was stored at the site from 1946 until early in 1948 in drums. This was transferred to the Lake Ontario storage area in 1948 and 1949 after most of the material had been reworked to recover additional uranium values. The raffinate (AM-10) produced after the pitchblende ores were used was stored separately. A barium cake residue (AJ-4) produced by the refinery is also stored at the site. This residue is a result of a precipitation to reduce sulphate content of digest liquor. African Metals Corporation has relinquished ownership of the barium cake.

In 1955 an interim residue plant was constructed at the Destrehan Street site to scalp a major portion of the uranium content from the magnesium fluoride slag produced in the Metal Plant.

Tailings from this operation were stored in the concrete pit at the site. About 350 tons of the pitchblende raffinate (AM-7) was processed in a small pilot plant facility at Destrehan Street to recover ionium. This material was processed in 1955-1951 and returned to the original raffinate storage at the site.
*Source