The present invention provides a self-foaming sprayable composition for forming a cover layer over material to be protected such as (1) refuse such as trash and garbage at a landfill site, (2) hazardous waste material at a hazardous waste site, (3) spoil piles or leaching piles at a mining site, (4) a remediation site, (5) a soil surface, (6) a stockpile of material such as grain, ash pits, salt o