Fort McClellan Ammunition Storage Area, Building No. 4409, Second Avenue (Magazine Road), Anniston

Source document Quoted word for word from HABS AL-988-D. Not written, edited or summarised by this site.

The Ammunition Storage Area of Fort McClellan represents two eras of building design. Buildings and are standard field depot magazines built in while Buildings and are igloos dating to Both sets of buildings provide information on the evolution and technology of safe ammunition storage between the World Wars. The buildings in particular afford a case study of a developing technology as they are early examples of igloo magazines. While igloos swiftly replaced earlier types, the materials used in their construction and the manner in which they were built varied. The Fort McClellan examples were constructed with corrugated steel plates and concrete and engineering practices that were directly borrowed from early twentieth-century culvert or tunnel technology.

FORT MCCLELLAN AMMUNITION STORAGE AREA, BUILDING HABS No. AL-988-D (page 2) A. General Statement: 1. Historical summary: Building is one of nine historic igloo magazines (Buildings through built in at the onset of World War II. Real property records indicate that it was completed in January according to Quartermaster General Plan 652-354-Igloo, at a cost of and it was considered a permanent building. The contractor's name was not given. The standardized plan used in Buildings through was not on file at Fort McClellan nor at other military archives contacted. The main challenge during the igloos' construction was to expand the existing magazine area using adequate safety distances without compromising the utility of earlier magazines and by fully utilizing the land available.

The new design for ammunition magazines was in response to a disastrous explosion in Lake Denmark, New Jersey in The igloo design is credited to J. M. Michaelson in under the auspices of the Navy. The examples of igloo magazines at Fort McClellan represent a scaled down version of the standard igloo design as represented in the Michaelson drawings or those constructed at Anniston Ordnance Depot in They were tailored to suit the fort's less demanding ammunition storage needs and were built with a strong emphasis on expediency.. While their foundations and footings may have closely resembled their Anniston Ordnance depot counterparts, their above ground construction employed a dramatically different technology. Instead of concrete, the Fort McClellan examples were composed of metal.

Culvert and tunnel technology that used these specially designed, pre- formed metal sections was easily adapted for this use, particularly by firms such as Armco who benefited financially from this marriage of need to available technology. MULTI-PLATE sections were used in their barrel arches while Steelox sections were used for the end walls. Both products were manufactured by Armco. 2. Architectural character: The igloo magazines at Fort McClellan are earth-covered metal structures with inverted half-barrel shapes and interior rectangular plans. Adequate safety distances and topography were the factors which guided the location and design of the World War Il igloos.

Since a functional area already existed, the new magazines continued the alignment along Second Avenue past the curve and also along two nearby unimproved roads. The cadence of the igloos is essentially the same as the older magazines but their unconventional forms juxtaposed with the character of the older buildings is visually jarring. While the latter resemble small barns or storehouses, the igloos, due to their earthen cover and shape, are more akin to prehistoric mounds. The size of the igloos also overwhelm their World War I counterparts. B. Description of Exterior: 1. Overall dimensions: This one-story building is rectangular in plan with dimensions of 24' x Historic property records and current property records do not agree on the igloo's dimensions.

The dimensions given above were taken from the current real property data as the architectural recordation indicated that they were correct The historic property data may reflect the FORT MCCLELLAN AMMUNITION STORAGE AREA BUILDING HABS No. AL-988-D (page 3) , desired sizes that were planned in Presumably, changes were made to accommodate the site and its topography. 2. Foundations: The poured concrete foundation is separate from the exterior frame and features edge gutters along the igloo's long, parallel walls. As no plans were located for this building, the best information on the building's footprint comes from demolition data.

Demolition of two of these igloos has revealed an unexpectedly large foundation of sufficient size that the contractor involved requested additional funding to complete the demolition process. 3. Walls: The head and end walls are constructed of 12 overlapped, vertical strips of flat sheet metal bolted together. These sheets, known as Steelox metal sections, were produced by Armco. Metal flashing finishes the exposed or upper edge of these walls. A vent pipe projects on an angle from the end wall. 4. Structural systems, framing: The arch and head and end walls are composed of metal sections. Wooden bracing has been added to the center of the arches to forestall sagging. 5. Porches, stoops: A concrete loading dock lies outside the head wall.

On the south elevation it is three feet high with a ramp . 6. Chimneys: None. 7. Openings: a. Doors: An oversize metal door is centrally located in the head wall providing the only access to the building. It has a rectangular vent on the lower right hand corner. b. Windows: None. 8. Roof: Corrugated sheet metal, known as MULTI-PLATE, was used in the arch. MULTI-PLATE was the product of the American Rolling Mill of Ohio (Armco) which first developed these heavy corrugated sections bolted together to serve as wide diameter culverts in It appears that this technology was modified and used at Fort McClellan to construct the arched portion of the igloos.

The MULTI-PLATE sections in Building and in other buildings were stamped with the trade name, "Ingot Iron," a 3 ounce steel coating that was patented in by Armco. The arch section was bolted to the head and end wall, a water proof "membrane" was applied and the arch covered with earth. Information gathered from the demolition of two of the study buildings has indicated that this membrane consisted of coats of tar and pitch. Research has established that the igloos at Anniston Ordnance Depot were waterproofed with three plies of felt applied with hot coal tar pitch. Fort McClellan's igloos may have been similarly treated as they shared the same contractor and the felt may have disintegrated over time. FORT MCCLELLAN AMMUNITION STORAGE AREA, BUILDING HABS No. AL-988-D (page 4) 9.

Other: Lightning rods are mounted behind the head and end walls and a grounding cable extends downward above and around the door. The igloo is further protected by a mast type air terminal mounted on a treated telephone pole on the southeast elevation. A fire extinguisher is attached to the exterior head wall. C. Description of Interior: The interior of Buildings is open. The sole light source stems from the open door. The only interior features are the floor's edge gutters and wooden frame supports that are centrally positioned to provide additional support to the building's arch. Comparative standardized drawings and published data suggest that the arch of the standard igloo magazine had a 10 foot radius.

However, as no plans were found, this standard may not have been used with Fort McClellan's examples. Currently, Building arch has a radius of 6 feet 10 inches. The interior bracing was needed to forestall the sagging of the arches but the real property records do not note when the bracing was added. D. Site 1. General setting and orientation: Fort McClellan's ammunition supply buildings are clustered at the foot of Reservoir Ridge and south of Cave Creek on the northeastern perimeter of the main building area. Situated at some distance from the military community, Reservoir Ridge acts as the Ammunition Supply Area's eastern boundary and also defines a portion of its northern extent.

The pine- forested ridge and the flat lands to the west and north, which are also covered in pines and heavy vegetation provide a sense of enclosure. The perimeter of the area is bounded with six foot high chain link fencing and lights mounted on telephone poles which are equally spaced along the fence's interior. The treeline begins fairly close to the perimeter fence which is capped with spiraled wire. Restricted Area signs are promi~ent. An open space to the south of the fence is a partial remnant of a historic coal storage yard. Only gravel and some trash dumpsters refer to this former usage.

A railroad spur and Second Avenue offer the only access to this restricted area which is stewarded by contractors housed in a temporary frame building that lies directly outside and to the south of the enclosure. Building lies between Second Avenue and the railroad spur to the northeast of where they curve. It is oriented with its door facing the southwest. 2. Historic landscape design: The Ammunition Supply Area has a partially dendritic shape. It contains 17 ammunition supply buildings and powderhouses, that are situated along the northern end of Second Avenue and two unnamed unimproved roads. Second Avenue, known historically as Magazine Road, is a paved dogleg, terminating in a dead end.

Further access to the area is provided by a railroad spur that leads northward from the Warehouse Supply Area and curves around the magazines that lie west of Second Avenue. The railroad lies within 4.7 feet of the magazines it serves. The pre-World War II magazines (Buildings are characteristically aligned with the railroad spur and Second Avenue, sandwiched between the rails and the road. The former was FORT MCCLELLAN AMMUNITION STORAGE AREA, BUILDING HABS No. AL-988-D (page 5) curve to the northeast, the row of early magazines is followed by three earthen- covered, inverted half-barrel-shaped igloos and that follow the cadence and alignment set by the barn-type magazines.

Building is located south of Second Avenue, and the five remaining historic igloos are situated on the unnamed roads which reach up into the ridge. 3. Barricade: This igloo does not have a barricade. Prepared by Mary Beth Reed Historian I Architectural Historian New South Associates September,