a pit with a septic tank before the pit
                                                            
                                                     
                        
                                                
                        
                        
                            a covered porous walled pit through which treated effluent may seep into surrounding porous soil.
                                                            
                                                     
                        
                                                
                        
                        
                            A pit in which sewage drains from a septic tank, and which is so constructed that the liquid waste seeps through the sides of the pit into the ground.