THIS DRAWING SHOWS ONE VERSION OF THE ENVIROSAFE SEWER COVER, THE SURFACE DRAIN INSERT WITH THE OPTIONAL CLEAN OUT INSERT, INSTALLED IN A TYPICAL SURFACE DRAIN CATCH BASIN.  THE CLEAN OUT INSERT IS USED TO REMOVE SOLIDS THAT COLLECT IN THE SURFACE DRAIN INSERT.  THE SURFACE DRAIN INSERT PROVIDES CONTINUOUS FLOW WHILE MAINTAINING A WATER SEAL THAT PREVENTS HYDROCARBONS FROM ESCAPING TO THE ATMOSPHERE, THEREBY COMPLYING WITH EPA AIR QUALITY REGULATIONS RESTRICTING EMISSIONS OF VOC'S SUCH AS BENZENE.  THE THE SURFACE DRAIN INSERT ACTS AS A SEPARATOR AND COLLECTS 70% TO 80% OF ANY SOLIDS THAT FLOW INTO THE SURFACE DRAIN.   A MINIMUM WATER SEAL DEPTH OF 6" IS RECOMMENDED TO PREVENT BACK PRESSURE FROM FORCING ANY HYDROCARBON VAPORS THROUGH THE WATER SEAL ONCE THE SEWER SYSTEM HAS BEEN SEALED.  THE SURFACE DRAIN INSERT CAN PREVENT SEWER EXPLOSIONS BY ELIMINATING CONTACT OF SEWER GASES WITH AN IGNITION SOURCE.

COVERED BY U.S. PATENT NO.'S    4,682,907;    4,776,722;     5,028,320;    5,062,735