The document provides a timeline of early settlement in the Oak Ridge, Tennessee area from the 1600s through World War II and the Manhattan Project. It details the Cherokee presence in the 1600s, white settlement beginning in the 1700s, and the establishment of schools and post offices in the 1800s-early 1900s. It then discusses the development of nuclear research in the 1930s-1940s that led to the secret Manhattan Project and the construction of facilities in Oak Ridge beginning in 1943, including K-25, Y-12, and S-50 plants.

1. TIMELINE (INDEX.HTML) • K-25 SITE TOUR (../SITE-TOUR/INDEX.HTML) •
LIFE IN HAPPY VALLEY (../HAPPY-VALLEY/INDEX.HTML) •
PRESERVATION (../PRESERVATION/INDEX.HTML) •
SHARE YOUR STORY (../SHARE-YOUR-STORY/INDEX.HTML)
EARLY SETTLEMENT
(1600s-1908)
1600s
Early European explorers into East Tennessee area
encounter native tribes living in large villages. The
ethnographic tribe in the Oak Ridge area became known
as Overhill Cherokee with the center of their population
in the Little Tennessee River Valley.
(../index.html)

2. Map of Tennessee and Portions of Bordering States
Library of Congress
(../img/ea-1790s-1b.jpg)
1791
U.S. President, George Washington, and Chiefs and
Warriors of the Cherokee Nation of Indians sign Treaty
of Holston, relinquishing a large tract of Cherokee land
east of the Clinch River for settlement.
June 1, 1796
Tennessee becomes 16th state.
Map of Tennessee (detail)
Library of Congress
(../img/ea-1790s-2b.jpg)
1798

3. The Treaty of Tellico opened the land west of the Clinch
River to settlement. However, due to failure to mark the
boundaries of the treaty, white settlers had been living
on the land for a number of years.
1799
Elias Roberts buys 500 acres on the Clinch River at the
mouth of Poplar Creek. More than 100 years later, the
property becomes part of covert U.S. military strategy.
1801
Anderson and Roane Counties (Tennessee) established.
1838
Poplar Creek Post Of ce opens in the area known as
Bald Hill.
1881
Henry Franklin Wheat opens a post of ce in Bald Hill.
The post of ce and community became known as Wheat.
1897
Cambridge University's Joseph John (J.J.) Thomson
discovers the electron.

4. Wheat School building, constructed in 1916
Bonita Irwin Collection
(../img/ea-1908-wheat-school.jpg)
1908
Wheat School established (meets in former Roane
College building). New brick facility constructed in 1916.
PRE-WAR
(1919-1941)
1919
New Zealand-born Ernest Rutherford discovers the
proton.
1930
American scientist Ernest Lawrence invents the
cyclotron, what he calls a "proton merry-go-round."
Lawrence's invention of the cyclotron later led to the
use of the calutron
(https://www.y12.doe.gov/sites/default/ les/history/pdf/info_materials/05-
0181.pdf) (California University cyclotron) at the covert
military site to be built in East Tennessee 12 years later.

5. 1931
At Princeton University, Robert Van de Graaff develops
the electrostatic generator, which continues to advance
atomic study.
1932
English physicist James Chadwick discovers the neutron.
1934
Enrico Fermi's discoveries during neutron bombardment
will lead to nuclear ssion.
1935
Tennessee Valley Authority launches cooperative
program to improve agriculture through fertilizers,
farming techniques, and business practices. Wheat
community is chosen to be a part of the program.
Hitler and Mussolini in Munich, Germany, ca. June 1940
National Archives
(../img/06_Hitler_Mussolini.jpg)

6. November 1, 1936
An alliance between Nazi Germany and Fascist Italy
becomes the Rome-Berlin Axis.
December 17, 1938
German physicists Otto Hahn and Fritz Strassman split
the uranium atom. The process is coined " ssion" in a
paper published by Lise Meitner and her nephew, Otto
Robert Frisch, in the journal Nature on February 11,
1939.
August 2, 1939
In letter to President Franklin Delano Roosevelt, renown
scientist Albert Einstein warns that the nuclear chain
reaction could lead to the construction of "extremely
powerful bombs."
Video Clip (http://www.youtube.com/embed/8FXSrVaTuAg?rel=0
View Letter (../img/08_Einstein_Letter_1.jpg)
September 1, 1939
Germany invades its neighbor to the east, Poland,
marking the of cial start of World War II.
October 19, 1939

7. President Roosevelt establishes an Advisory Committee
on Uranium to investigate current research on uranium;
authorization for limited research funding soon followed.
1940
A team of Columbia University scientists investigate
uranium isotope separation by the gaseous diffusion
method sponsored by the Naval Research Laboratory.
Adolf Hitler in Paris, June 23, 1940
National Archives
(../img/12_Hitler_Paris.jpg)
June 1940
Nazi forces occupy Paris.
June 1940
Convinced that the United States could not escape
involvement in World War II, advisors to President
Roosevelt request the creation of a formal scienti c
body to organize research efforts pertaining to the war
effort. Subsequently, the president establishes the
National Defense Research Committee "to coordinate,
supervise, and conduct scienti c research on the

8. problems underlying the development, production, and
use of mechanisms and devices of warfare." Foreign-born
scientists were excluded from membership on the
committee but included in research and development
activities.
June 1940
U.S. halts oil shipments to Japan after Japanese troops
invade French-colonized Indochina.
September 27, 1940
Japan of cially joins the "Axis" Alliance with the signing
of the Tripartite Pact.
February 24, 1941
Glenn T. Seaborg's research group at the University of
California, Berkeley discovers plutonium.
American airplanes shipped to England
FDR Library
(../img/15_Lend-Lease.jpg)
March 11, 1941
Despite public and congressional support of isolationism
due to the trials of the Great Depression and signi cant
human losses in World War I, President Roosevelt rallies
support for the Lend-Lease Act, which allowed the U.S.
to aid its allies with war supplies.

9. June 28, 1941
Days after Germany invades the Soviet Union, the Of ce
of Scienti c Research and Development is established by
Executive Order. With direct access to the president and
authority to enter into contracts and agreements, the
Of ce quickly engages the scienti c community.
July 1, 1941
The Of ce of Scienti c Research and Development
awards Columbia University a contract to study the
gaseous diffusion process under the direction of
Professor John R. Dunning. The diffusion research
facilities at Columbia are code-named SAM Laboratories
for Special Alloyed Materials.
View Document (../img/32_SAM_Laboratories.jpg)
WWII & MANHATTAN PROJECT
(1941-1946)
December 7, 1941
Japanese bomb Pearl Harbor; U.S. declares war on
Japan.
Video Clip (http://www.youtube.com/embed/hbFoCNe8t3Q?rel=
December 11, 1941
Germany and Italy declare war on the United States.

10. January 1942
Japan captures Manila (Philippines).
January 15, 1942
The M.W. Kellogg Company hired to perform
engineering studies and experimental work on gaseous
diffusion.
January 19, 1942
President Roosevelt approves atomic weapon production.
Ultimately, the United States would pursue two paths to
bomb development – uranium separation and plutonium
production.
April 1942
U.S. and Filipino soldiers surrender to Japanese troops
on the Bataan Peninsula in the Philippines. In what was
later called the Bataan Death March, 75,000 prisoners
were forced to walk 60-plus miles across the peninsula
to war camps. Thousands died on the brutal march and
subsequent imprisonment.
Summer 1942
As the project moved from pure research to production
planning, leadership transferred to the armed forces. An
Army of cer would assume overall command of the
project. The of cer would execute his assignment
through the expertise of the Corps of Engineers, the

11. Army's engineering and construction division. The Of ce
of Scienti c Research and Development would continue
to oversee research and pilot plant studies and advise
the Army of changes/updates that would in uence
engineering and design.
June 4-7, 1942
U.S. Navy defeats Japan in the Battle of Midway, a
turning point for Allied forces on the Paci c front.
August 13, 1942
The Army Corps of Engineers establishes the project's
rst headquarters – the Manhattan Engineer District –
at 270 Broadway in New York City. Soon known as the
Manhattan Project, its headquarters would immediately
move to Washington, DC. Within a year, East Tennessee
becomes the center of Manhattan Project operations
nationwide.
General Groves
(../img/24_General_Groves.jpg)
September 17, 1942
The Army appoints Colonel Leslie R. Groves to command
the Manhattan Project. Six days later, he is promoted to
Brigadier General. His resume includes the recently
completed Pentagon, the world's largest building under
one roof at the time.

12. September 19, 1942
Groves expedites acquisition of a rural site in East
Tennessee for production (uranium) and pilot (plutonium)
facilities. Clinton Engineer Works, named for the county
seat of Anderson County, would span nearly 60,000
acres. Surrounded on three sides by water, the
landscape included natural barrier ridges that planners
hoped would provide some protection from production
accidents and would promote concealment from
saboteurs.
Three uranium enrichment plants will be built using
gaseous diffusion (K-25), electromagnetic isotope
separation (Y-12), and liquid thermal diffusion (S-50)
methods. Pilot pile (reactor) and plutonium separation
facilities are built and operated in what becomes known
as X-10 area.
Map of Tennessee
(../img/25a_K-25.jpg)
Clinton Engin
(../img/25b_K
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November 25, 1942
Groves selects Los Alamos, New Mexico, as site for
separate scienti c laboratory to design an atomic bomb.
December 2, 1942

13. At the University of Chicago, scientists led by Enrico
Fermi achieve the rst self-sustained nuclear chain
reaction in pile (reactor) constructed under the west
grandstand at Stagg Field.
December 14, 1942
M.W. Kellogg receives authorization to proceed with
engineering on a large-scale gaseous diffusion plant.
December 28, 1942
President Roosevelt authorizes and funds construction
of full-scale gaseous diffusion and plutonium production
plants in addition to electromagnetic
(https://www.y12.doe.gov/sites/default/ les/history/pdf/info_materials/y12-
general-history-booklet.pdf) and heavy water facilities.
January 1943
Scientists and engineers continue to struggle with design
and manufacture of the porous barrier material required
for successful uranium enrichment using the gaseous
diffusion process. When an Edward Norris/Edward Adler
design appeared to provide the highest probability for
success, General Groves authorizes full-scale production.
The Houdaille-Hershey Corporation would build and
operate the facility in Decatur, Illinois.
January 16, 1943

14. Groves selects Hanford, Washington, as site for full-scale
plutonium production and separation facilities. Three
reactors - B, D, and F - are built.
January 20, 1943
Carbide and Carbon Chemicals Company, a Division of
Union Carbide and Carbon Corporation, accepts
contract to operate the large-scale gaseous diffusion
plant in Tennessee.
January 22, 1943
For security and accounting reasons, the M.W. Kellogg
Company creates Kellogg Experimental or Kellex
Corporation to execute gaseous diffusion design.
February 9, 1943
After six-month campaign, U.S. takes Guadalcanal in the
Solomon Islands, capturing Japan's farthest-reaching
outpost.
Clinton Engineer Works
(../img/31_Clinton_Engineer_Works_Map1.jpg)
Map of Oak R
(../img/31_Cl
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15. April 13, 1943
A site 11 miles southwest of Clinton Engineer Works'
town center (later to become Oak Ridge, TN) is selected
for the gaseous diffusion plant. The site was west of
McKinney Ridge on Poplar Creek, near the Wheat
School.
May 1, 1943
Gaseous diffusion studies at Columbia University were
taken over by the Manhattan Project with the work
being directed by H.C. Urey.
May 18, 1943
The J.A. Jones Construction Company signs contracts to
build the powerhouse and cascade buildings as well as
administration area at Clinton Engineer Works.
Special Engineer Detachment Barracks
(../img/34_K-25.jpg)
May 22, 1943
To address the need for more technical and scienti c
personnel to support the project, the Army creates the
Special Engineer Detachment (SEDs). These highly
skilled individuals were drafted, then deployed to
Manhattan Project sites. More than 1,200 SEDs joined
the project in Oak Ridge.
Video Clip (http://www.youtube.com/embed/1DBeAfO_GXA?&st

16. June 3, 1943
Groundbreaking for K-25 powerhouse.
September 16, 1943
Jones Construction begins work on main gaseous
diffusion process building, K-25. The four-story, U-
shaped building spanned 44 acres and was just under a
mile in length from end-to-end. For a time, the K-25
Building would replace the Pentagon as the world's
largest building under one roof. Construction
commences before a barrier solution is determined.
Video Clip (http://www.youtube.com/embed/jlVFAoiwb9g?rel=0
Fall 1943
In a crash barrier production effort, Kellex develops
improved barrier design.
January 1944
General Groves accepts Kellex barrier design and directs
modi cation of the Houdaille-Hershey facility to
manufacture the new product. Click HERE
(http://www.manhattanprojectvoices.org/people/percival-
dobie-keith) to read Percival "Dobie" Keith's (head of
Kellex Corporation) discussion on the barrier.
Powerhouse - 1944
(../img/39_K-25.jpg)
March 15, 1944

17. K-25 powerhouse begins operation.
Eisenhower on D-Day
FDR Library
(../img/40_Eisenhower_D-Day.jpg)
June 6, 1944
D-Day: Allied troops invade the northern coast of France
(Normandy), beginning liberation of Nazi-occupied
Europe.
0:000:00 / 1:42/ 1:42
June 21, 1944
General Groves orders construction of a liquid thermal
diffusion process, later known as S-50.
September 1944
Just 69 days after construction begins, the rst unit (or
rack) at S-50 is complete. By October, the plant delivers
a slightly enriched uranium product (0.852) to the Y-12
Electromagnetic Separation Plant
(http://www.y12.doe.gov/about/history/).
September 1944
K-25 Plant receives rst natural uranium feed from the
Harshaw Chemical Company for the enrichment process.

18. December 17, 1944
At Wendover Army Air Field in Utah, crews of the
509th Composite Group
(http://www.enolagay509th.com/bobhistory.htm) begin
practice "Pumpkin Bomb" drops in preparation for
atomic weapon deployment.
January 20, 1945
Sixteen months after construction begins, the rst K-25
cell becomes operational.
First Cell Operational
(../img/44a_K-25.jpg)
Cell Schemati
(../img/44b_K
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S-50 Thermal Diffusion Plant
(../img/46_S-50.jpg)
March 1945
S-50 Thermal Diffusion Plant fully operational. Initially, S-
50 product was fed to Y-12 Electromagnetic Separation
Plant. As of late April, S-50 product becomes feed
material for K-25 Plant. S-50 enriched product is only
slightly higher than naturally occurring uranium (from
0.71 to 0.89 percent).

19. Flag Raising on Iwo Jima
National Archives
(../img/ ag.jpg)
March 16, 1945
U.S. troops secure the island of Iwo Jima. Nearly 7,000
marines lose their lives in the 36-day battle.
March 19, 1945
First uranium product from K-25 Plant shipped to the Y-
12 Electromagnetic Separation Plant
(http://www.y12.doe.gov/about/history/) for additional
enrichment. As no enrichment facility was fully
operational, a combination of methods would be used to
produce quantities required for weapon production. K-
25's initial product is enriched to 0.826 percent, only
slightly higher than naturally occurring uranium (0.711
percent). However, uranium product assay progressively
increased to 7% in June 1945, exponentially increasing
output of the Y-12 Plant. K-25 product assay continued
to rise steadily in 1945 to 12% in July and 23%
between August and October.
K-27 Construction
(../img/47_K-27_Construction.jpg)
April 3, 1945
Construction begins on second gaseous diffusion
building, K-27.

20. April 12, 1945
President Franklin Roosevelt dies; Harry S. Truman
becomes the 33rd president. On April 24, President
Truman is briefed on the Manhattan Project – from
inception to current status.
Roosevelt Funeral
FDR Library
(../img/48_Roosevelt_Funeral.jpg)
Truman takes
Truman Library
(../img/48_Tr
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May 1945
Total employment at the K-25 plant peaks at 25,266.
Germany Surrenders
FDR Library
(../img/50_Germany_Surrenders.jpg)
May 7, 1945
Germany surrenders unconditionally to allied forces at
Reims, France.
June 22, 1945
After 82 days of engagement, Allied forces seize the
island of Okinawa. More than 200,000 Americans,
Japanese, and Okinawans die in what becomes the

21. "bloodiest battle" of the Paci c.
Trinity "gadget" bomb prior to detonation
(../img/trinity_test.jpg)
July 16, 1945
At 5:30 a.m., Los Alamos scientists detonate the rst
atomic (plutonium) bomb at a test site named "Trinity,"
located on the U.S. Air Force base at Alamogordo, New
Mexico.
July 26-29, 1945
Potsdam Declaration calls for unconditional surrender of
Japan or warns of "prompt and utter destruction." Three
days later, Japan rejects Potsdam terms.
August 6, 1945
Little Boy atomic bomb dropped on Hiroshima, Japan.
The weapon, the rst ever used in warfare, was fueled
by enriched uranium produced in Manhattan Project
facilities in Oak Ridge. The K-25 Gaseous Diffusion
Plant, fueled by natural uranium feed and slightly
The Knoxville News-Sentinal -
August 6, 1945
(../img/52_Bomb_Drop_Newspaper.jpg)
Little Boy ato
(../img/52_K-
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22. enriched uranium from both the S-50 Liquid Thermal
Diffusion Plant and the Y-12 Plant, produced uranium
enriched to approximately 23%. K-25 product was then
transported to Y-12 Electromagnetic Separation Plant for
nal enrichment.
Video Clip (http://www.youtube.com/embed/i0F3eNbGFpM?rel=
Fat Man atomic bomb
(../img/53_Fat_Man.jpg)
August 9, 1945
Fat Man atomic bomb (plutonium-fueled) dropped on
Nagasaki, Japan.
War Ends
(../img/54_War_Ends.jpg)
August 14, 1945
At 7 p.m., President Truman announces Japan's
agreement to conditions of Potsdam Declaration.

23. Video Clip (http://www.youtube.com/embed/bDHdXRdMHBI?re
August 15, 1945
All 54 units of K-25 fully operational – 24 months after
construction begins. That same month, power
consumption peaked for Clinton Engineer Works
facilities, reaching 200,000,000 kWh. That is enough
electricity to power 20,000 homes for a year.
K-25 Control Entrance
(../img/55a_K-25_Control_Entrance.jpg)
K-25 Exterior
(../img/55d_K
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September 2, 1945
General Douglas MacArthur, Supreme Allied
Commander, accepts Japan's unconditional surrender
aboard the U.S.S. Missouri.
September 9, 1945
With the success of the gaseous diffusion process, the S-
50 liquid thermal diffusion process ceases operations.
K-27 - 1946
(../img/56_K-27_1946.jpg)

24. December 19, 1945
Eight months after construction begins, rst three units
of K-27 are operational.
January 1946
K-25 enrichment reaches 28 percent; 90-plus percent
enrichment is required for weapons production.
February 7, 1946
Last two units in K-27 operational; process lines tie K-25
to K-27 to expand the uranium enrichment capacity.
August 1, 1946
Atomic Energy Act signed; transferred atomic research
and development responsibilities from the U.S. Army to a
ve-member civilian board known as the Atomic Energy
Commission. The Act became effective on January 1,
1947.
COLD WAR & CIVILIAN NUCLEAR
POWER
(1946-1991)
December 2, 1946
K-25 enrichment reaches weapons-grade output (90-plus
percent).

25. December 1946
The electromagnetic separation facility at Y-12 is shut
down, making K-25 gaseous diffusion plants sole U.S.
supplier of enriched uranium.
December 1947
On-site barrier plant and uranium feed plant begin
operations.
1950
Cascade improvement program begins. Over the course
of 30 years, major improvements and upgrades to the
U.S. gaseous diffusion process will improve production
by 60 percent without increasing plant size.
December 1950
Gaseous diffusion production expands with the
construction of a plant in Paducah, Kentucky.
K-29 - 1950
(../img/65_K-25.jpg)
January 24, 1951
K-29, Oak Ridge's third gaseous diffusion process
building, becomes operational.

26. K-31
(../img/66_K-31.jpg)
December 9, 1951
The site's fourth gaseous diffusion process building, K-
31, begins operations.
July 10, 1952
Plans announced for expansion of Oak Ridge and
Paducah plants and for construction of a new gaseous
diffusion facility at Portsmouth, Ohio. K-25 facilities
were training ground for many key personnel deployed
to Paducah and Portsmouth.
November 7, 1952
Interplant operations begin between Oak Ridge and
Paducah gaseous diffusion plants.
K-33
(../img/69_K-33.jpg)
November 4, 1954
The fth and nal gaseous diffusion process building in
Oak Ridge, K-33, begins operations.
All Gaseous Diffusion Process Buildings
(../img/70_K-25.jpg)
1955

27. K-25 serves as the nal link in a multi-building
production chain - including Buildings K-27, K-29, K-31,
and K-33 − that produces weapons-grade enriched
uranium.
Oak Ridge Gaseous Diffusion Plant - 1971
(../img/71_Name_Change_ORGDP.jpg)
1955
Name of K-25 Plant changed to Oak Ridge Gaseous
Diffusion Plant (ORGDP)
September 17, 1956
First shipment of enriched uranium made under Atomic
Energy Commission's Civilian Applications Program
(http://ansnuclearcafe.org/2013/12/19/atomic-power-for-
peace-the-civilian-application-program-and-power-
demonstration-reactor/).
1960
Atomic Energy Commission initiates experimental work
on centrifuge technology at the K-25 site. Back in 1919,
scientists suggested the use of gas centrifuge as a
method of isotope separation. In 1934, Dr. Jesse Beams
at the University of Virginia successfully demonstrates
the rst isotope separation using the gas centrifuge
method. Due to several inherent technical problems in
the approach, Manhattan Project leadership rejected the
centrifuge method for further development. From 1946-
1958, Russia continued to develop the gas centrifuge
method. The U.S. reactivated its centrifuge work in the
mid-1950s at the University of Virginia.

28. 1961-1963
The rst centrifuge cascades (35) operate successfully at
Oak Ridge, demonstrating gas centrifuge feasibility.
Technology advancement continues through the mid-
1980s.
February 1962
Gaseous diffusion plants ship their millionth pound of
uranium hexa uoride for use in the Civilian Applications
Program.
President Johnson - State of the Union
LBJ Library
(../img/76_Johnson_SotU.jpg)
June 1964
K-25 and K-27 process buildings shut down as a result
of President Lyndon Johnson's order to reduce national
enriched uranium production by 25 percent. Two units in
K-25 continue to operate as a "purge cascade" to
remove nitrogen, oxygen, and other light gases from
process equipment.
Video Clip (http://www.youtube.com/embed/E_q5LP7PTqM?rel=
1967
Oak Ridge Gaseous Diffusion Plant, in cooperation with
the Oak Ridge National Laboratory, develops a
centrifuge for producing ultra-pure vaccines. Patented by
the government and transferred to industry, these

29. centrifuges were used by Dr. Jonas Salk for early
batches of his polio vaccine and by Eli Lilly Company to
produce the rst large batches of puri ed in uenza
vaccine.
K-1423 Toll Enrichment
(../img/78_K-1423.jpg)
1969
K-25 found new life when a "toll enrichment" program
was created to provide low enrichment (3-5 percent)
uranium for fuel in civilian power reactors; Japan was
the site's biggest customer.
1975
Centrifuge Test Facility (K-1210) begins operation.
1977
President Carter announces plans to use centrifuge
technology for the next enrichment plant to be built in
Ohio.
1977
The purge cascade in K-25 was replaced with an
improved purge cascade in K-27 for removal of nitrogen,
oxygen, and light gases from the process. The K-25
purge cascade soon shuts down.

30. Advanced Equipment Test Facility
(../img/83_AETF_K-1008.jpg)
1978
Advanced Equipment Test Facility (K-1210-A)
constructed on the site. The facility was used from 1978
to 1985 to test reliability of production centrifuges.
1982
Centrifuge Plant Demonstration Facility (K-1220) built
on the site to test production centrifuges and
successfully demonstrates the producibility,
constructability, and operability of equipment for a gas
centrifuge enrichment plant in Ohio.
Centrifuge facility interior
(../img/85a_Centrifuge_Interior.jpg)
Gas Centrifug
(../img/85b_C
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April 1982
The Department of Energy begins large-scale
engineering, development and demonstration efforts on
Atomic Vapor Laser Isotope Separation (ALVIS). Site
employees contribute to design and operation of the full-
scale demonstration module as well as conceptual design
studies for an ALVIS production plant.

31. July 1982
Barrier Plant (K-1037) shut down.
January 1983
Materials Handling Demonstration Module, key
component of the AVLIS process, installed at former
ORGDP Barrier Plant (K-1037).
April 1, 1984
Martin Marietta Energy Systems becomes contractor at
ORGDP, replacing Union Carbide - Nuclear Division.
Operations at ORGDP placed in standby
The Oak Ridger
(../img/89_ORGDP_Standby.jpg)
June 5, 1985
The Department of Energy announces that gaseous
diffusion operations at Oak Ridge will be shut down and
placed in standby as soon as possible after 40 years of
service. All research and development work on the
advanced gas centrifuge program would be terminated.
AVLIS is selected as the enrichment process of the
future.
K-25 gaseous diffusion facilities shutdown
(../img/90_K-25.jpg)
August 27, 1985

32. At 3:31 p.m., the nal gaseous diffusion operating
equipment at Oak Ridge shuts down.
1987
The Department of Energy begins a major environmental
cleanup effort.
1989
Oak Ridge Gaseous Diffusion Plant renamed Oak Ridge
K-25 Site.
1991
Cold War ends.
CLEANUP AND
REINDUSTRIALIZATION
(1991-Present)
1991
Toxic Substances Control Act (TSCA) Incinerator begins
operation treating hazardous and radioactive wastes
containing polychlorinated biphenyls from the gaseous
diffusion process buildings and other DOE facilities.
1996

33. The Oak Ridge K-25 Site becomes the East Tennessee
Technology Park (ETTP) to re ect the Department of
Energy's long-term goal of converting the site into a
private-sector industrial park. The Community Reuse
Organization of East Tennessee (CROET) is established
with its initial focus on the lease of underutilized
facilities. A portion of ETTP is designated a brown eld
site called The Heritage Center.
1998
Just east of the brown eld site known as The Heritage
Center, CROET establishes a green eld industrial park,
the Horizon Center. The Horizon Center is over 1,000
acres and approximately half of it is set aside for
environmental conservation, greenways, and wildlife
corridors.
1999
The Department of Energy designates K-25 as a
Manhattan Project "Signature Facility" for its essential
role in interpretation of the historic project.
Deactivation
(../img/97_K-25.jpg)
2002
Deactivation activities begin at K-25.
2002

34. The Environmental Management Waste Management
Facility (EMWMF) disposal site opens to accept
contaminated waste from numerous cleanup projects.
2003
CROET's emphasis transitions from leasing to title
transfer, which enhances the development opportunities
at the site.
2005
The Black Oak Ridge Conservation Easement (BORCE)
is established as part of a Natural Resources Damage
Assessment compensation for environmental impacts to
the Watts Bar Reservoir. The BORCE includes nearly
3,000 acres as a permanent easement that is managed
by the Tennessee Wildlife Resources Agency.
August 2006
K-29 demolished.
December 2006
Completed off-site shipment of approximately 6,000
cylinders of depleted uranium hexa uoride and another
1,200 empty and near-empty cylinders containing
residual uranium compounds from the ETTP. Depleted
uranium hexa uoride is a by-product of the uranium
enrichment process.

35. January 4, 2008
DOE transfers the K-25 Fire Station (Building K-1652)
to the City of Oak Ridge.
2008
K-25 demolition begins. Demolition was completed on
December 19, 2013.
K-25 demolition
(../img/101a_K-25.JPG)
K-25 demoliti
(../img/101b_
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December 2009
TSCA Incinerator closed after 18 years of service, having
treated 35 million pounds of waste.
September 2011
K-33 demolition complete.
August 7, 2012

36. TIMELINE (../TIMELINE/INDEX.HTML) • K-25 SITE TOUR (../SITE-TOUR/INDEX.HTML) •
LIFE IN HAPPY VALLEY (../HAPPY-VALLEY/INDEX.HTML) •
PRESERVATION (../PRESERVATION/INDEX.HTML)
SHARE YOUR STORY (../SHARE-YOUR-STORY/INDEX.HTML) • ABOUT (../ABOUT/INDEX.HTML) •
VISIT (../VISIT/INDEX.HTML) • CONTACT (../CONTACT/INDEX.HTML)
SPOTLIGHT (../SPOTLIGHT/BILL-WILCOX/INDEX.HTML) •
ORAL HISTORIES (../ORAL-HISTORIES/INDEX.HTML) • HOME (../INDEX.HTML)
Information contained within this website has been reviewed and approved for public release and has been determined to be
unclassi ed and non-sensitive.
The website is operated and managed by URS|CH2M Oak Ridge LLC (UCOR) for the United States Department of Energy and is
designed and maintained by Westside Media (http://www.westsidemedia.com)
A Memorandum of Agreement signed to preserve
historic contributions of the K-25 Site to the Manhattan
Project and Cold War.
December 19, 2013
K-25's nal wall falls.
Video Clip (http://www.youtube.com/embed/UQU2W6k7XZw?r
June 2015
K-31 demolition complete.