[Conroy]

pawn Код:

if(strcmp(cmdtext, "/placemine", true) == 0)
{
    if( gPlayerClass[playerid] == ENGINEER )
    {
    SetPlayerHealth(giveplayerid, 10);
    new Float:boomx, Float:boomy, Float:boomz;
    GetPlayerPos(giveplayerid,boomx, boomy, boomz);
    CreateExplosion(boomx, boomy , boomz, 7, 10);
    }
return 1;
}

Unsure if the command works, I just changed your { }'s about.