Masan-dong, Yongsŏng district, Pyongyang

The Maram Chemical Corporation, along with the Chiha-ri Materials Corporation, is responsible for the storage and supply of chemical weapons. The firm manages the storage of solid and liquid chemical agents in underground tunnels and four-meter tanks, respectively. Defector Yi Chung Kuk, who claims to have served with the 18th Nuclear Chemical Defense Battalion, has diagrammed the locations of related sites below:

Legend:
1. Public Security Department, vehicle repair facility
2. Maram Materials Company
3. Previous site of Antinuclear/Antiatomic Analysis Center (before 30 March 1991)
4. Recreational Center for South Korea Liaison Office
5. Missile warehouses
6. Tunnels
7. Chemical ammunition stockpile center
8. Warehouses
9. Sleeping quarters
10. Maram Materials Company office building
11. Liquid tank storage area
12. Map Bureau automated warehouse
13. (Direction of P'yongsŏng)
14. Food warehouse
15. Housing for the officers and workers serving on the base
16. Map Bureau barracks
17. Main gate
18. Direction of Tongbuk-ri Station
19. Precious stones processing plant
20. Direction of P'yongyang
21. Direction of Chun-ri Station
22. Masan-dong Military Base, Yongsŏng district, Pyongyang

Sources:
[1] Yi Ch'ung Kuk, "Assignment to Antinuclear/Antiatomic Analysis Team," in the book "Kim Chong-il's Nuclear Weapons and Army," Kin Seinichi no Kaku to Guntai in Japanese, 21 September 1994, pp. 101-10;
[2] Joseph S. Bermudez, Jr., "Inside North Korea's CW Infrastructure," Jane's Intelligence Review, August 1996, p. 380; Osamu Eya, Kimu Jon Iru Daizukan (Tokyo: Shogakkan, 2000), p. 65;
[3] Osamu Eya, Kimu Jon Iru Daizukan (Tokyo: Shogakkan, 2000), pp. 64-65, in "Alleged Locations of DPRK Nuclear, Biological, Chemical Warfare Facilities Mapped," 6 June 2001, FBIS Document ID: KPP20010606000075;
[4] Chang Chun Ik, Pukhan Haek-Missile Chŏnjaeng (Seoul: Sŏmundang, 1999), pp. 364, 368;
[5] "Pukhanŭi Hwasaengbangjŏn'nŭngnyŏk: Haekpangwiguk Chiksok 8 Kae Chŏnt'udaedae," Chosun Ilbo, 13 June 1994, p. 4, in KINDS, www.kinds.or.kr;
[6] "Puk Haekhwahakpangwiguk: Haeksaenghwahangmugi Ch'ongjihwi," Segye Ilbo, 21 May 1997, p. 17, in KINDS, www.kinds.or.kr.