Project Description

The former Forbes Atlas Missile Site S-5 (Forbes S-5 Site) was an operational intercontinental ballistic missile launch facility from 1959 to 1965.  The Atlas Missile Program was an important but short-lived element of the United States’ defense system.  The Forbes S-5 Site was one of nine (9) former Series “E” Atlas Missile Sites located around Forbes Air Force Base, Topeka, Kansas. The site is located in Lyon County, Kansas, approximately 8 miles west of Allen, Kansas and approximately 45 miles southwest of Topeka, Kansas. The Forbes S-5 Site consists of approximately 25 acres within a general rectangular area and is surrounded by agricultural grazing lands.

Environmental contamination at the Forbes S-5 Site resulted from waste management practices during the facility’s operational period.  Much of this is groundwater contamination beneath the site.  Contaminants in the soil were not detected above respective screening criteria.  Sediment and water samples taken the main sump, sediment trap, flame tunnel, and various pits located in and around the missile base structure, were determined to be potentially a source of groundwater contamination at the Site. In 2018, an Interim Remedial Action was performed to remove the water and sediments from the sump, sediment trap, and flame pit structures.

Operational History

In 1959, the U.S Air Force started construction on the nine Forbes Atlas E missile facilities. Operation of the Forbes S-5 Site was the responsibility of the 548th Strategic Missile Squadron (SMS) assigned to the Former Forbes Air Force Base in Topeka, Kansas. The 548th SMS was activated in 1960 and missiles first started arriving at the SMS sites in January 1961. The 548th SMS was declared “Operationally Ready” in October of 1961. The Forbes S-5 facility operated from 1961 until 1965, when it was decommissioned and excessed.

The Atlas E type missiles were composed of the SM-65 variant and were housed in a "coffin launcher" style complex. The missile was kept in a horizontal position and in order to launch, a 400-ton hardened concrete overhead roof was rolled back after which the missile was elevated to a vertical launch position. Once upright, the rocket was fueled with RP-1 (kerosene) and liquid oxygen (LOX). The Atlas E missiles were equipped with a Mark IV re-entry vehicle and carried a type W-38 warhead which had a yield of approximately 4 megatons of trinitrotoluene. The Atlas E missile had a range of approximately 6,000 miles. 

The facility is currently a private property.