The Indiana Army Ammunition Plant (INAAP) was constructed after the passage of the first National Defense Appropriations Act.10 Four days after the passage of the Act, the Munitions Program was passed in which the U.S. Ordinance Department sponsored private manufacturing corporations to design and produce ammunition factories, producing smokeless gunpowder and other ordinances. INAAP was the largest of these facilities.


The development of Indiana Army Ammunition Plant was mired in speculation. Rumors began to spread when C.V. Artwell, a real estate operator from Delaware, was taking options on land between Charlestown and the Ohio River.30 In July 1940, the Courier-Journal announced that the world’s largest smokeless powder plant would be constructed on the site of historic residences, homesteads, churches and pioneer cemeteries, as well as the former Rose Island Amusement Park.1 There was little resistance from those affected, who accepted that the loss of their land was a sacrifice to the foreseeable cost of war.  The facility would be the largest plant in the Industrial Operations Command, containing 1,401 structures on 9,790 acres, although the figure would total much larger.1 It was estimated to cost $50 million at the time.30

When it was announced that the plant would be constructed adjacent to Charlestown, workers from across the country descended upon the small town, creating what is now referred to as a boomtown.30

“Every day is a Saturday in boomtown Charlestown, and Saturday is mostly chaos.”

-Minneapolis Star Journal, February 194130

The farming village was transferred within a few months, when 13,000 workers descended upon Charlestown. Street corner markets popped up, schools became overcrowded, and rental prices became astronomically high. Rooms in the village were rented per shift for sleeping purposes, and garages and chicken huts were converted into bedrooms. In addition, seventeen trailer parks were constructed that contained more units than the city’s 250 homes.30 The post office went from one clerk to nine to handle a 300% increase in mail and surging money order requests that were related to the plant’s $400,000 per week payroll. The library doubled as classroom space for the local school.30

Construction & World War II

A contract was let for a government-owned, contractor-operated ammunitions plant to the E.I. du Pont de Nemours Company for the production of a smokeless powder plant to be titled Indiana Ordinance Works.10 Construction was overseen by the Quartermaster Corps.

The assembly of the smokeless powder plant was one of three separate manufacture facilities that encompassed the Indiana Army Ammunition Plant (INAAP). Constructed on 19,200 acres, INAAP included the Indiana Ordnance Works Plant 1 (IOW1) that produced smokeless powder, the Hoosier Ordnance Plant (HOP), also referred to as the “bag plant,” and the Indiana Ordnance Works Plant 2 (IOW2) that was referred to as the “rocket plant.”10 11 The three facilities were consolidated into the Indiana Arsenal on November 30, 1945, as designated under the WD Circular No. 329.9 11

Construction began on August 26, 1940 under E.I. du Pont de Nemours & Co.,11 and just three months later, over 10,000 workers had been employed in the building of IOW1.10 At the height of construction in May 1941, there were 27,520 workers employed in the building of the plant. IOW1 was completed in May 1942 at a cost of $74,956,394.11

IOW1 contained 800 buildings that were divided into four main areas.9 10 The administration area included a main administration building, telephone exchange, hospital, repair ship, cafeteria, guard headquarters and office space. The smokeless powder manufacturing area included six parallel, nearly identical manufacturing lines that included two power plants, blending towers, two Ammonium Oxidation plants, and two Nitric and Sulfuric Acid Concentration plants. Further south was the storage and shipping area that included approximately 100 above ground magazines, road ship houses and road storage and shipping houses. Towards the Ohio River was River Ridge, a collection of 19, two-story, wood-frame houses.

Construction began on the Hoosier Ordnance Plant (HOP) on January 10, 1941.11 and was partially in operation by September.10 Construction was completed on February 2, 1942 at a cost of $27,851,660.65.11 Contractors for HOP included Winston Bros. Co., C.F. Haglin and Sons Inc., Missouri Valley Bridge and Iron Co., and Sollitt Construction Co., Inc.11 The load, assembly and pack facility was used to prepare cannon, artillery and mortar projectiles and integrated five distinct areas.9 10

The administration area included a main administration building, a main change house and a hospital, and the production, maintenance and storage area contained a bag manufacturing building, inert stores warehouse, a repair shop, a fire station and a heating plant. A charging area contained eight load lines for bag loading smokeless powder and four igniter lines for bag loading black powder, whereas the powder magazine area contained 177 earth-covered, steel-reinforced concrete igloos. At River Ridge, an additional 17 two-story wood-frame houses were constructed.

Construction on Indiana Ordnance Works Plant 2 (IOW2), a rocket propellant plant, did not begin until December 8, 1944.11 Although production did take place for approximately five weeks, the plant was never completed before the surrender of Japan in August 1945.10 Construction stopped on August 13 under E.I. du Pont de Nemours & Co.11

In total, the Indiana Army Ammunition Plant contained 19,200 acres, 1,700 buildings, 84-miles of railroad track, 190 miles of road and 30 miles of fence and cost $133.4 million to complete.10 30 There were 50 time clock stations, and three shift changes at 7 A.M., 4 P.M. and at midnight.30

Initial Production

IOW1 began producing smokeless powder and black powder to HOP and other load, assembly and pack operations on April 11, 1941.10 11 Single-base smokeless powder, or nitrocellulose, was used as a propellant for a projectile, while black powder was used to ignite the smokeless powder. By July, IOW1 had produced twice as much powder as the entire nation had the previous year.10 30

Peak employment occurred on May 1, 1941, when 27,250 contractors and 366 government officials oversaw production at IOW1. Production at IOW1 stopped on September 7, 1945.11

HOP began operations on September 2, 1941 that involved bag manufacturing and the load, assembly and pack process. Smokeless powder was weighed, placed in a bag and sewn shut. Each charge consisted of up to seven bags of powder secured together. The increments were placed in an outer charge bag and then packed in containers and shipped or warehoused.

Nitrocellulose from IOW1 was loaded into bags made at HOP.30 The hallmark product was a 16-inch diameter bag of powder that when loaded six deep in the breech of a battleship’s turret, could propel a 2,750 pound bullet 25 miles.

HOP employed 8,902 contractors and 87 government officials by March 20, 1945, which rapidly declined by the time production ceased on August 18.11

IOW2 was in operation from July 20, 1945 to August 31,11 and was designed to manufacture double-base rocket powder. Double-base powder was unlike single-base in that it consisted of a 60 to 40 ratio of nitrocellulose and nitroglycerin that was used to power bazookas and other rocket-based weapons. IOW2 produced 292,700 lbs. of rocket powder during its succinct operation.10 Employment at IOW2 peaked at 17,585 contractors and 36 government officials on June 30, 1945. On February 11, 1946, IOW2 was placed into standby status and was never reactivated.11

After VE Day in August 1945, 5,000 workers laid off in a single day.30

Post-World War II

Between June 24, 1946 and March 31, 1950, E.I. du Pont de Nemours & Co. activated and operated facilities for the production of ammonium nitrate aqueous solution for agricultural purposes under a CPFF contract. Peak employment came on February 1, 1947 with 156, and peak production cumulated in August 1949 with 20,241 tons of ammonium produced.11

At IOW2, the 44 Richmond-type above-ground magazines were used for propellant storage from January 1946 to August 1952.11

Korean War

In 1948, IAAP was partially reactivated but did not return to full-scale production of military goods until 1952 during the Korean War.1 10 IOW1 was reactivated on April 28, 1952 by du Pont de Nemours & Co., reaching peak personnel on August 1953 with 8,067.11 HOW was reactivated on September 17, 1951 by the Goodyear Engineering Corp., with peak personnel of 8,067 by August 1953. During the war, fifty new storage and maintenance buildings were constructed on-site.

Production at HOW ended on September 20, 1957, followed by IOW1 ten days later.11 IAAP was once again placed into standby status at the conclusion of the involvement of the United States in the war, and Goodyear and duPont were listed as the caretakers of the complex until 1959, when that function was taken over by the Liberty Powder Defense Corporation, a subsidiary of the Olin Matheison Chemical Corporation.1 10

Vietnam War

During the early 1960s, IAAP was host to numerous production difficulties including faulty sewing machines and scales, short lead-times, incomplete technical data and quality control issues due to a lack of experience for quality assurance inspectors.10 The problems were mostly resolved when Olin Mattheison began to hire some Goodyear and DuPont employees.

On November 1 1960,11 the Liberty Powder Defense Corp. reactivated the Bag Manufacturing Building to produce cloth bags for 105mm artillery charges for the Vietnam War.10 Two months later, Olin Matthieson dissolved Liberty Powder and took over direct control of the plant’s operations, which coincided with the reactivation of the igniter and propellant loading lines. Those two lines were supplied black powder and smokeless powder from other ammunition factories, and IAAP did not manufacture black powder directly. IAAP was not officially reactivated until August 23, 1961.11

On November 1, IAAP was designated the Indiana Ordnance Plant by DAGO No. 40.11

On August 1, 1963, the facility was re-designated as the Indiana Army Ammunition Plant by DAGO No. 35.9 11 Peak personnel during the Vietnam War reached 11,492 employees on August 16, 1970, with 3 military officials and 93 government civilians.11 Six years later, Olin reactivated part of IAAP’s smokeless powder manufacturing area, and continued to manage IAAP until 1972, when ICI America Incorporated, a subsidiary of Imperial Chemical Industries PLC, took control of the facility.10

By the end of the Vietnam War, IAAP featured 576 industrial buildings at 2,052,521 square-feet, 149 warehouses at 617,019 square-feet, 114 standard magazines at 299,311 square-feet, and 176 igloos at 646,887 square-feet.11 IAAP also contained three research-and-design structures at 3,992 square-feet, 34 administrative buildings at 186,583 square-feet, 21 utility structures at 279,681 square-feet, and 566 miscellaneous structures at 3,302,029 square-feet. Acreage remained steady at 10,647.65 acres, less than the original 18,169.41 acres that IAAP featured during World War II.

IAAP featured 161.2 miles of paved and 5 miles of unpaved roads, 49 miles of 100 pound and 35 miles of 40 pound railroad track, served by the Baltimore and Ohio and the Pennsylvania Railroad, and three railroad yards. Two yards, the Watson that could hold 200 cars with inert materials and the Bethany that could hold 60 cars with explosive materials, were located within the bag loading unit. The third yard was the Ridley, holding 425 cars within the propellant manufacturing unit.11

IAAP was served by 68,750 KVA turbo generators that were contained within two coal-fired power plants, and used only 5,570 KVA of electricity from Public Service Co. of Indiana.11 Numerous deep water wells along the Ohio River supplied 50,200 GPM of water to the plant. Several sanitary surge disposal units could handle 1,048,000 gallons per day.

The facility also featured 36 two-story frame houses constructed in 1941, 12 1.5-story frame houses built in 1945, and one two-story house that was acquired with the initial purchase of property for IAAP in 1940. The 49 individual housing units were contained within a tract of 395 acres, providing quarters for military and key contractor personnel. It contained a community center for adults and children, a swimming pool, horseshoe pits, baseball diamond, volley ball court, basketball court and two locations of assorted play items for children.11

IAAP also featured two medical facilities. One was located in the bag loading unit in Building 2601 (Employment Building) that contained male and female wards, a laboratory, X-Ray equipment and a whirlpool. The second was in the propellant manufacturing unit.11

In February 1971, the IAAP installed air pollution control equipment in the main coal-burning power plant.14 The electrostatic precipitators removed dust, ash and other participles from the smokestack. In addition, the Ammonia Oxidation Plant was replaced with a modern, pollution free facility. The replacement of the ammonia oxidation facility removed a source of nitrogen oxide fumes that produced a yellowish cloud over the plant at times.

Cold War

After the United States withdrew from Vietnam, the federal government began a major modernization project of the ammunition manufacturing facilities.10 IAAP was aging and featured a number of limitations dating to its World War II-era design and technology. In an attempt to modernize the plant, ICI began construction of three new facilities.

Construction of an entirely new, fully-automated Black Powder Manufacturing Facility (INAAP-074) encompassed the first of three new projects that began in December 1974,18 with contracts awarded to Sante Fe engineering. ICI Americas completed process equipment sub-contract awards.

Construction and equipment installation were completed in December 1978,10 18 with debugging sustained through 1979.9 This facilities check determined that additional engineering was required to “correct process deficiencies and enhance safety.”18 As a result, major problems were found in the black powder fines recycling system, electrical grid grounding system, process humidity control and black powder conveyance systems. A three-phase program was developed which addressed select deficiency corrections, a second prove-out and a long-term project to implement a final facility upgrade. In 1980, inert material was processed through the plant during proveout.9 The deficiency correcting process was completed on schedule and within cost in February 1982. Small modifications were made until August, and during February and March 1983, 2,200 pounds of black powder were produced.

The facility, occupying nearly 30 acres within a 140-acre site to the north of the administration area, included a raw materials building, a process building, four glaze houses, a screen house, and a pack house. Several auxiliary buildings built included a boiler house, maintenance shop and a change house. It featured the capacity to produce 500,000 pounds of black powder per month 16 and cold be operated by remote control using state-of-the-art technology and computerized systems with only ten employees.18 The design emphasis was based on limiting personnel exposure while adapting technology to meet production goals.

The new plant successfully concluded its live explosive prove-out on April 15, 1983.18 The new $40 million 10 black powder facility was formally dedicated on April 22 after nine years of development.18 It was one of two such facilities in North America, the other being in Moosic, Pennsylvania.18

The plant was deactivated immediately following proveout and was not reactivated. In 1988, INAAP sought a corporation with $15 million to invest to operate the black powder plant and operate the plant for 20 to 25 years.23 The plant, considered a disappointment, could not meet production quotas and design problems that stem from an outdated computer system dating to 1974.

Two separate but integral buildings were also on site. The Black Powder Sanitary Sewage Treatment Plant (INAAP-014) was constructed in 1977,9 and featured a rapid mix chamber, flocculation chamber, settling chamber, filter sludge holding tank, final aeration, and chlorination. It was rarely used and was essentially non-operational. The Black Powder Industrial Wastewater Treatment Plant (INAAP-015) was also constructed in 1977 and was non-operational for its lifespan.9

The two other modernization projects for IAAP undertaken in the 1980s included a semi-automated loading line for 105mm charges and a similar assembly line for 8 inch and 155mm charges.10 The 105mm charge structure was completed in 1980 and the facility for the 8 inch and 155mm charge line was completed a year later. At the time of their completion, the lines were placed into standby status.

The End of the Cold War

With the Cold War waning by the late 1980s, employment levels at IAAP wildly fluctuated. Employment levels throughout the Vietnam War were sustained around 19,600, but dropped to 700 by 1976 as production of powder declined.10 The work force rose only slightly to 1,500 for most of the 1980s, but by 1987, major layoffs were once again announced for the plant due to a decline in military contracts.

At the same time, IAAP officials were hoping to land a new production facility for the next generation of booster rockets for the NASA space shuttle.17 In 1987,20 Atlantic Research Corporation of Arlington, Virginia considered IAAP’s former IOW2 rocket plant and present-day Charlestown State Park for the production site of Advanced Solid Rocket Motors, however Atlantic Research chose Yellow Creek, Mississippi’s abandoned Tennessee Valley Authority’s nuclear power plant for the site.10 17

There was also hope that IAAP would be a forerunner for a $350 million 22 research explosives production plant and an industrial waste-treatment facility.13 Charlestown was one of four sites considered. The others were Iowa Ammunition Plant in Middletown, the Joliet Army Ammunition Plant in Joliet and the Louisiana Army Ammunition Plant in Shreveport. The Charlestown Research Department Explosive (RDX) facility would be part of “mobilization planning efforts for national security,” and would supplement the sole RDX facility at Holston Army Ammunition Plant in Kingsport, Tennessee.

In the event of a military attack, sabotage or accident, the total U.S. production capability of RDX would be immobilized if production efforts remained solely at Holston. In addition, the Holston plant had insufficient space for construction of additional production facilities and had been operating beyond its design capabilities for years.13

The RDX plant would be approximately 3,200 feet from IN 62, cover 25 to 50 acres and be capable of producing 2.5 million pounds of RDX per month. The initial employment reports stated that the RDX plant would employ 8,000, however, those numbers were grossly inflated and that the number of actual jobs would be closer to 300.10 22 The Courier-Journal reported that those 300 jobs would exist only “if the country were to go to war, or if the Kingsport, Tennessee plant (…) blew up.” At peak construction, only 1,000 jobs would be needed over a time period of four years. Congress did, however, allot $75,000 for an environmental impact study.22

In the end, IAAP never received the RDX production facility.

In February 1989, the U.S. Army sought a private firm to operate the automated Black Powder Manufacturing Facility (INAAP-074).16 Three companies, GOEX of Moosic, Pennsylvania, Ensign-Bickford Industries Inc. of Simsbury, Connecticut and ICI Americas toured the facility, however no decision was made to utilize the plant.

The failure to land either of the plants, along with the end of the Cold War and a reduction of production orders after nearly a decade of stockpiling charges, convinced the Army to consider closure of IAAP as the facility had become outdated and replaced with more modern plants. Technology had simply passed IAAP, and budget cuts had affected the Defense Department.32 On March 10, 1989, approximately one-third of the jobs at IAAP were laid off, including 388 production and maintenance jobs, 51 technical positions, 39 clerical and secretarial jobs, 86 management and supervisory positions and one guard.15

The U.S. Army later decided to cease production at the Indiana Army Ammunitions Plant in August 1991 which would require the laying off of 1,003 employees.12 U.S. Representative Lee Hamilton and U.S. Senator Dan Coats, however, helped IAAP obtain two munitions orders, one to prepare a line of propellant charges for other Army depots, and the other for a large quantity of 155mm propellant charges, which extended the closure date to October 1992. At the time of the closure, only 750 were employed.10 The facility had produced 3.2 billion pounds of black powder.30


In October 1992,10 production ceased at IAAP and the facility was placed into inactive and modified caretaker status.1 Under the Armament Retooling and Manufacturing Support (ARMS) legislation, ICI America was permitted to seek long-term adaptive reuse of the IAAP facility in hopes that the property holding costs would be reduced while ownership stayed with the military.29 When ICI America executives approached the county about sharing reuse proceeds, and made a down payment to have a study done in regards to the issue, the county used the funds to start lobbying for total control of IAAP.

The Army plant commander’s office closed its post in 1994,2 and the plant was transferred to civilian patrol. IAAP was maintained by ICI America under modified caretaker status, which was later transferred to Tecumseh Professional Services, government contractors, whose purpose was to construct an industrial park to compensate the loss of ammunitions production.2 On May 9, 1995, the Indiana Army Ammunitions Depot was renamed “Facility One.”1 During this time, there were several lawsuits filed by several local municipalities and the Clark County Commissioners over attempts by several communities to annex parts of IAAP. Several of the lawsuits were also in relation to the Clark County Redevelopment Commission.10

In 1997, special legislation sponsored by the 9th District Congressman Lee Hamilton attempted to transfer 6,000 acres of the plant to the Clark County Reuse Authority, then known as the IAAP Reuse Authority, under a lease. The remaining 4,000 acres would go to Charlestown State Park.29 On November 30, 2000, the Army signed an interim lease agreement to turn over 6,000 acres of the plant to the Clark County Reuse Authority.

Environmental Issues

IAAP faced environmental problems that stemmed from 50 years of black powder and explosive material manufacturing.10 From a 1995 study, 87 areas of the plant were identified as contaminated, with another 53 areas cited as potential problems. A 1998 study estimated that it would take more than $250 million to remedy to the plant, with work to begin immediately and be complete by 2003. Another study by the Army Corps of Engineers pegged the value at $33 million.6 Little work towards that goal, however, was completed.

On February 6, 2004, demolition began on the first ten buildings on the southernmost fringe of IAAP.24 Because the buildings contained gunpowder dust and other explosive residue, demolition via machinery and human intervention was not possible. As an alternative, a fire burn permit was ordered and the buildings were set ablaze. The burning permit an environmental permit that stated,

“Burning shall only take place only when the wind is predominantly out of the west or southweste and there are no unfavorable meteorological conditions such as air stagnation or high winds.” 25

The environmental permit was revised on February 11 in response to an apparent violation of the initial permit.24 Additional burns left elevated levels of lead present in the air that exceeded federal air quality standards, however, because the lead levels were elevated for only a brief period of time, no violation of air standards occurred.27

A total of 64 buildings were burned in February, and a total of 327 buildings were proposed to be demolished within the decade. Over 1,000 buildings existed at IAAP that would need remediation and demolition.26


Facility One employed featured 80 tenants employing over 800 by 2000.2 In mid-2000, Facility One was renamed to River Ridge Commerce to reflect the transformation of the industrially-based IAAP into a commercial and light-industrial park.10

On June 18, 2001,8 a master plan for River Ridge Commerce Center, then a 5,370-acre industrial park, was approved. The plan included a short-range plan that excludes 40% of the IAAP property due to explosives and environmental cleanup and would focus attention on the land closest to Indiana State Route 62.8 Targeted industries include manufacturing, distribution, retail and office covering about one-fifth of the total land area. Included in the master plan was the demolition of most of the industrial buildings, as most were single-use structures related to ammunitions production. The plan called for 3,800 workers at the former IAAP plant after the first ten years of development.28

On June 1, 2005, Army officials granted title to 2,308 acres of IAAP to River Ridge in four deeds at a cost of $1,131 per acre.31 Twenty-four additional acres in the administration complex were transferred in April 2008.28 The 703 Building today houses the Charlestown Business Center, while another structure was reused for the Wilson Education Center.

In late 2000, only 750 of the Commerce’s 6,000 acres were immediately available to businesses,6 however this had increased to 2,925 acres by 2005.10 As of July 2006, 3,077 acres were clean and available.26

The two power plants, unused since 1992, were demolished in phases from October 2011 until late 2012 at a cost of $1.1 million.33 The contract, awarded to ADS Trinity, involved scrapping 335 tons of salvageable materials from the site and the demolition of the 120,000 and 145,000 square-foot structures and their 180-foot smokestacks.


INAAP was divided up into several distinct districts: Administration area, propellant and explosives area, black powder manufacturing plant, powder burning area, burning area, planning area, shipping houses, powder preparation area, igloo area, and propellant charge lines.9 10

The propellant and explosives area, at 1,500 acres, was a single-based propellant manufacturing facility that operated intermittently from 1941 to 1970.9 The major process areas included two nitric acid manufacturing areas, two nitrocellulose manufacturing and purification areas, and two propellant manufacturing and finishing areas. Major support areas included an aniline manufacturing area, two coal burning power plants, approximately 450 above-ground storage tanks, and an extensive railroad system.

The administration area included many critical support structures. One such building, Structure 719, was a hospital and a laboratory. Constructed in 1941, this was once a 12,563 square-feet hospital; it later became part of an employment office. 9 By 1985, it was no longer a hospital or employment office, and became a laboratory from 1987 to 1990.

The igloo area occupies approximately 1,700 acres and features 176 earth-covered igloos that have been used to store propellants since 1941. 9 One noteworthy mention is that Igloo 5185 was destroyed in an explosion in 1966.


Most of the labor force at INAAP were men, although a considerable number of women were employed. At IOW1, approximately one-fourth of the employees were women, while at HOP, women composed two-thirds of the workforce.10 Approximately 10% of INAAP workers were also black, although segregation was in effect and blacks were not given office jobs.

German prisoners-of-war were used as unskilled labor, and were housed in the IOW2 area neighboring Charlestown Landing Row. The first German prisoners-of-war arrived in May 1945, but were repatriated three months later as the war ended.10


Due to the presence of black powder and other highly volatile materials, safety was one of the utmost concerns at INAAP. Buildings on the industrial campus were spread far from one another to diminish the chance of a mass explosion, and transfer chutes were utilized that reduced airborne powder movement.10 In addition, conductive shoes were issued to reduce static electricity, and employees were searched daily for matches and other hazardous materials. In addition, emergency slides were installed in some buildings to provide quick escape.


Administration Area

Propellant & Explosives Area

Air Test House

After packing the powder into shipping containers, the powder is taken to the Air Test House where each container is checked to ensure that it is air tight. This is done to prevent the powder from collecting moisture which can modify its ballistic nature.

Blending & Wringler House, Building 113- & 113-3

The Blending and Wringer House was part of the nitration process. In order to obtain a uniform propellant and ballistic characteristic, portions of batches that have a high nitrogen content are mixed with portions that have a low nitrogen content. Slurry from the poaching tubs in the Poaching House were fed onto vibrating screens where nitrocellulose was blended, which passed into collecting boxes. The boxes were then emptied into tubs where guncotton and pyrocellulose were blended. If the sample from the tub had satisfactory nitrogen and solubility content, the slurry was pumped into the Wringer House. At the Wringer House, the large amounts of water that were used throughout the process to move the nitrocellulose is removed. The containers of partially dry nitrocellulose are transported to the Dehydration/Press House via lag cars.

Change House Building 707-

Comfort Station Building 727-

Control Circulation Dry House Building 220

The Control Circulation Dry House dried the remaining solvent out of the powder before it went to the blending tower, where it would be blended to achieve a set burn rate.

Cotton Dry House Building 104

The Cotton Dry House is where cotton linters, or short fibers that cling to cottonseeds after the first ginning was delivered in 150 pound bales, or wood pulp delivered in rolls of 700 pounds, where they were shredded. They were then pretreated in large ovens to reduce the moisture to less than 1% before being blown in ducts to the Nitrating House.

Debagging Building 218-1A

Dehy Press House Building 202

The Dehy Press Houses (Building 202) pressed the cake of nitrocellulose into a powder form.

Ether-Mix House Building 206-3

Horizontal Press House Building 211

Knife Grinding & Die Shop Building 217-2

Laboratory Building 706-3

Main Laboratory Building 706-1

Mixer House Building 208

The Mixer Houses (Building 208) mixed and kneaded powder. A Baker-Perkins mixer and kneading machine had a 100-gallon capacity.

NC Lag Storage Building 201

Nitrating House Building 105

With shredded cotton being blown in from the Cotton Dry House, 32 pounds of cellulose fiber were mixed in stainless steel nitrators that contained 1,500 pounds of nitric and sulfuric acids that were blended together. The treated nitrocellulose and spent acids were then discharged from the bottom into centrifugal wringers that removed most of the acid through the exterior of the wringer. The acid was used in the production of pyrocellulose or fortified for reuse. Wet nitrated cotton was then immersed in water and the slurry transferred to the Boiling Tub Houses.

Poacher House Building 112

The poaching process was conducted to reduce the acidity of the nitrocellulose. It also reduced the fibers remaining to minute fragments in a mechanical operation. Hot water washes in sodium carbonate, an alkaline solution, further reduced acidity. The nitrocellulose was then bathed in cold water under mechanical agitators to purify the nitrocellulose and ensure for a longer shelf life. Samples were sent to a nearby laboratory to determine the percentage of nitrogen, the solubility of the ether-alcohol mixture and the fineness degree.

Power Pack House Building 221

Power Plant Building 401-1

Power Plant Building 401-2

Process Engineering Division Building 706-2

Pulping House Building 109

The Pulping House was where nitrocellulose fibers were cut into short segments to open the embedded fibers which exposed any remaining impurities in the capillary channels. During this process, a very large amount of water was used, which resulted in a slurry that was pumped into the Poaching House.

Pump House Building 402

Scrap Rework House Building 209-2

Scrap black powder was mixed with production black powder, and if it was not possible to reuse the powder because of residual acid, the product would be disposed of with a burn.

Solvent Recovery Building 214

The Solvent Recovery Houses (Building 214), where the solvents, ether and alcohol were extracted from the black powder, lie in endless rows. There were two architectural styles, brick and concrete, but were identical in function.

Sulfuric Acid Concentration House Building 303

The Sulfuric Acid Concentration Plant produced sulfuric acid by melting and burning raw sulfur, which produced sulfur dioxide gas. The gas was then passed over catalytic beds that produced sulfur trioxide gas, which was absorbed through distilled water that produced sulfuric acid.

Vertical Dress House Building 234

Warehouse Building 101

Water Dry House Building 219

The Water Dry Houses (Building 219) was where powder containing 3% to 5% of the solvent arrived and aged to free it of any remaining solvent. The powder was soaked in water.