Mission Support Alliance (MSA) 
P.O. Box 650
MSIN H2-23
Richland, WA  99352
(509) 376-8833
(509) 376-6962 (Benefits Helpline)

Washington Closure Hanford (WCH) 
2620 Fermi Ave
Richland, WA  99354
(509) 372-9162

CH2M Hill Plateau Remediation Company (CHPRC)
P.O. Box 1600
MSIN H8-20
Richland, WA  99352
(509) 376-1314  (Human Resources)

Washington River Protection Solutions (WRPS) 
P.O. Box 850
MSIN H6-17
Richland, WA  99352
(509) 372-3639

HPMC Occupational Medical Services
1979 Snyder Street, Suite 150
MSIN G3-70
Richland, WA  99354
(509) 376-3333