U.S. Navy Hospital Corpsman Miguel Barajas, Camp Lemonnier Expeditionary Medical Facility member, demonstrates how to use bleach to sanitize a 5-gallon water container here, March 26. The 490th Civil Affairs Battalion Functional Specialty Unit taught field sanitation certification training here March 26-30. The course included instruction on proper field sanitation techniques for maintaining clean air, water and food supplies while in the field, how to properly identify rodent and insect infestations and how to prevent them.