Announcing examination for engineering aid, mathematics aid, physical science aid $3,175 to $4,525 a year (grades GS-3 through CS-7), engineering technician, $4,970 to $7,570 a year (grades GS-8 through GS-12), physical science technician, $4,970 and $5,440 a year (grades GS-8 and GS-9), announcement 154.