Los Angeles -- Michael Wong-Sasso of Granada Hills, Calif., already is a garbage celebrity. He made national news Saturday when he and 40 of his pals rang in his seventh birthday at the Sunshine Canyon Landfill, Sylmar, Calif. The landfill, operated by Browning-Ferris Industries (Allied Waste Industries), Scottsdale, Ariz., hauled fresh dirt to a spot on the edge of the landfill to accommodate the partiers and did not charge the family a fee for using the site. Activities included clay sculpting with recycled materials and a demonstration from a ranger about native landfill wildlife. Wong-Sasso’s affection for the garbage industry has landed him press and notoriety. At age 4, he wrote a book about the local trash collector and, according to his mother, has been obsessed with garbage trucks since before he could talk.