Here is the full list of all 17 Base Squad 49 achievements.
BUILD_FULL_UPGRADE_BASE
BUILD_HALF_UPGRADE_WALL
GET_50000_GOLD
GET_15000_GOLD
BUILD_HALF_UPGRADE_BASE
BUILD_FULL_UPGRADE_WALL
COMPLETE_9_WAVE
GET_5000_GOLD
COMPLETE_5_WAVE
KILL_100_MONSTERS
KILL_75_MONSTERS
KILL_50_MONSTERS
BUILD_FIRST_UPGRADE_BASE
COMPLETE_1_WAVE
KILL_35_MONSTERS
KILL_10_MONSTERS
BUILD_FIRST_UPGRADE_WALL