By MALIA WOLLAN, The New York Times

SAN FRANCISCO – Throwing orange peels, coffee grounds and grease-stained pizza boxes in the trash will be against the law in San Francisco, and could even lead to a fine.

The Board of Supervisors passed new recycling and mandatory composting rules Tuesday in a 9-2 vote. The city already diverts 72 percent of the 2.1 million tons of waste its residents produce each year from landfills and into recycling and composting programs. The new law will help the city in its goal of sending zero waste to landfills by 2020, said Jared Blumenfeld, director of the city’s Department of the Environment.

Under the new law, all city residents will be issued three bins: a black one for trash, a blue one for recyclables and a green one for compost.

Garbage collectors who spot orange peels or aluminum cans lurking in a black trash bin will leave a note reminding citizens how to separate their trash properly. Anyone found repeatedly flouting recycling protocol will be issued fines of $100 for small businesses and single-family homes, and up to $1,000 for large businesses and multiunit buildings. There is a moratorium on all fines until 2011 while residents learn the ropes.

Reaction to the rules were as mixed as, well, recyclables.

“This takes big brother to an extreme I’m not comfortable with,” said Sean R. Elsbernd, one of two supervisors who voted against the proposal. “I don’t want the government going through my garbage cans.”

Garbage cops snooping through the refuse is not the intent of the new law, said Nathan Ballard, spokesman for Mayor Gavin Newsom.

Newsom, who proposed the legislation last May and doggedly championed it, is expected to sign it into law within 30 days.