23rd Chemical Battalion
"Moong Chi Ja"

The mission of the 23rd Chemical Battalion is to, on order, deploy and conduct operations in support of Combatant Commanders or other Government Agencies in order to counter Chemical, Biological, Radioactive, Nuclear, and High Yield Explosive threats.

The 23rd Chemical Battalion was first constituted on 27 May 1944 in the Army of the United States as Headquarters and Headquarters Detachment, 23rd Chemical Smoke Generator Battalion, and activated in England. During the Normandy invasion, the Battalion provided smoke support on land and sea. The Battalion was Inactivated on 12 November 1945 in France. For its service in the European Theater the Battalion earned 5 campaign streamers: Normandy, Northern France, Rhineland, Ardennes-Alsace, and Central Europe.

The unit was redesignated on 18 January 1949 as Headquarters and Headquarters Detachment, 4th Chemical Smoke Generator Battalion, and allotted to the Regular Army. The unit was activated on 1 February 1949 at the Army Chemical Center, Edgewood, Maryland. The unit later deployed to Korea and during the Korean War the Battalion provided smoke support to the United Nations Command, adding 10 campaign streamers to its unit colors: UN Defensive, UN Offensive, CCF Intervention, First UN Counteroffensive, CCF Spring Offensive, UN Summer-Fall Offensive, Second Korean Winter, Korea Summer-Fall 1952, Third Korean Winter, and Korea Summer 1953.

The Battalion was reorganized and redesignated on 4 March 1954 as Headquarters and Headquarters Detachment, 4th Chemical Battalion and took up station in Germany. The Battalion was inactivated on 15 June 1959 in Germany.

The Battalion was redesignated on 16 September 1988 as Headquarters and Headquarters Detachment, 23rd Chemical Battalion, and activated in Korea. The Battalion was assigned to the 20th Area Support Group of the 19th Theater Army Area Command. In January 1992 the Battalion was moved from the Song-So Site to Camp Carroll. The 23rd Chemical Battalion was ordered to reorganize in October 1997. This reorganization included the activation of 4 Corps/Theater Army Chemical Companies. Activation of all companies was completed in April 1999.

While in Korea, the 23rd Chemical Battalion was the only forward deployed US chemical battalion in the world. Organized into a Headquarters and Headquarters detachment and 5 decontamination companies, it had a wartime strength of 588. Of those, approximately 50 percent were US soldiers and 50 percent were Korean Augmentees to the United States Army (KATUSA) soldiers. In addition, 26 full-time Korea Service Corps personnel and 76 part-time members of the Korea Service Corps, who were mobilized for training at minimum of one week per quarter, contributed to the mission accomplishment of the Battalion. The Battalion was responsible for decontamination operations throughout the Republic of Korea in the 2nd Infantry Division sector.

KATUSA soldiers maDe up over 50 percent of the company personnel in the 23d Chemical Battalion. They formed the bulk of the decontamination soldiers and also served as administrative clerks, company supply soldiers, maintenance soldiers, and drivers. This unique manning authorization made the 23rd Chemical Battalion the first of its kind in the free world. The combination of US soldiers, KATUSA soldiers and full time Korean Service Corps personnel made the battalion a truly combined national force. The motto of the Battalion "Two Joined as One" (or "Moong Chi Ja," together, in Hangul) reflected the combined nation status of the 23rd Chemical Battalion.

The 23d Chemical Battalion was ordered on 24 Jun 2004 to inactivate its 267th and 501st Chemical Companies and its E Company (Heavy Decontamination Preposition Stock Chemical), transition it's Korean Theater of Operations COMZ Decontamination mission to the newly formed Republic of Korea Army's 19th Chemical Battalion, activate a newly formed Multi-COMPO Biological Defense Chemical Company, transition the Korean Theater of Operations mobile biological defense mission between the 13th Chemical Company (-) and 332d Chemical Companies (-), redeploy the 13th Chemical Company (-) to Fort Hood, Texas, and prepare its Headquarters and Headquarters Detachment, and 61st and 62nd Chemical Companies for redeployment to Joint Base Lewis-McChord no later than 16 December 2004.

The Eighth Army announced on 17 December 2004, that the Headquarters and Headquarters Detachment, 23rd Chemical Battalion and 2 chemical companies had completed their relocation from Korea to Fort Lewis, Washington, as the final phase of the chemical decontamination mission transfer to the Republic of Korea Army. According to the statement, the transfer of the chemical decontamination mission from the US military to the Republic of Korea military had been completed in August 2004 with the US military to eventually transfer 10 missions to the Republic of Korea military as part of the Strategic Policy Initiative (SPI) mutually agreed to by both nations. Placed under the administrative control of the 555th Engineer Brigade while in garrison, the unit was subsequently assigned to the 20th Support Command (CBRNE).

On 10 August 2006, the Battalion was called upon to provide support during the Tripod Complex Fire. Six platoons from the 23rd Chemical Battalion deployed with hundreds of other soldiers from units across Joint Base Lewis-McChord forming Task Force Blaze in order to battle the wild land fires spreading across Washington State. The soldiers were trained and performed wild land fire fighting tasks for the Okanogan and Wenatchee National Forests for 23 days and returned safely home on 3 September 2006.

On 24 January 2007, the 23rd Chemical Battalion deployed to Afghanistan in support of Operation Enduring Freedom 06-08 in support of Combined Joint Task Force-82, led by the 82nd Airborne Division. The Battalion was charged with executing non-standard operations of provided Base Operations Support to 5 Forward Operating Bases throughout Regional Command East, Capital and South, as well as augmented Task Force Cincinnatus Staff Sections.

While abroad, on 23 September 2007, the 23rd Chemical Battalion was reassigned to the 48th Chemical Brigade, located at Fort Hood, Texas, a subordinate unit of the 20th Support Command, US Army Forces Command (FORSCOM), at Aberdeen, Maryland. The Battalion remained at Joint Base Lewis-McChord, and administrative control in garrison was provided by the 555th Engineer Brigade, I Corps.

The Battalion redeployed from Afghanistan on 25 January 2008.

On 4 October 2012, the Department of the Army announced the relocation of the 61st Chemical Company, the 62nd Chemical Company, and Headquarters and Headquarters Detachment, 23rd Chemical Battalion, from Joint Base Lewis-McChord, Washington to the Republic of Korea. There the Chemical Companies would provide Nuclear, Biological, and Chemical reconnaissance, equipment decontamination and consequence management assistance to support military forces. This action was in support of Headquarters, Department of the Army initiatives involving US forces conducting a sustainable pace of presence operations abroad, including rotational deployments and bilateral and multilateral training exercises. These activities would reinforce deterrence, help to build the capacity and competence of US, allied, and partner forces for internal and external defense, strengthen alliance cohesion, and increase US influence. This force structure change represented an increase of 290 military and zero civilian authorizations within the Republic of Korea and a corresponding decrease in authorizations at Joint Base Lewis McCord. The Army expected to complete the stationing action by 16 January 2013.

On 6 December 2012, the 23rd Chemical Battalion cased its colors at Joint Base Lewis-McChord, Washington in preparation for its move to Camp Stanley, Republic of Korea. By that time, the battalion's relocation was to bring approximately 300 soldiers to Camp Stanley and was scheduled to be completed by March 2013. Once there, the Battalion's 61st Chemical Company, 62nd Chemical Company, 501st Chemical Company, would provide Nuclear Biological and Chemical reconnaissance, decontamination, and consequence management assistance to support US and ROK military forces. The relocation of the Battalion back to the Republic of Korea was part of a US Army's initiative to reinforce America's commitment to the US-ROK alliance.