Sonoma County has taken a big step toward a countywide ban on plastic carryout bags to reduce landfill waste and litter.

The county Waste Management Agency authorized its staff Wednesday to request proposals from consultants for environmental review of the proposed ban.

The agency also considered a proposed ordinance based on a San Jose law that went into effect Jan. 1.

Under the draft ordinance, all "retail establishments" would be prohibited from providing "single-use carryout bags" bags as of July 1, 2013. The ban would not only apply to grocery store, but to all retails shops except restaurants.

"I want everybody to understand we're not just talking about grocery stores," said Janet Coleson, the agency's legal counsel.

The draft ordinance would allow retailers to provide paper bags, though at a minimum cost of 10 cents a bag. A year later, such bags would cost a minimum of 25 cents.

A key question discussed Wednesday was whether the new bag ban should be a countywide rule or a model ordinance. The latter would require each local government to adopt and enforce.

A countywide ordinance could require the creation of an administrative enforcement ordinance. Local ordinances could be enforced by each of the municipalities that are part of the joint powers agency.

Under the proposed ordinance, a first-time violation would result in a $100 fine, and a second violation within one year of the first would get a $200 fine. The third and subsequent violations within a year of the first would land a $500 fine.

The agency's staff estimates that the cost of environmental review under the California Environmental Quality Act could be anywhere from $80,000 to $150,000.

In a model ordinance, individual boards and councils would be able to change the ordinance. The 10-member board is made up of representatives of each of the nine towns or cities in Sonoma County.

Henry Mikus, executive director of the agency, said local retailers prefer a uniform ordinance for the entire county because some business have shops in different towns and cities.

Board members will now take the proposed ordinance to each of the nine city or town councils for review and possible and possible changes. The agency will discuss the issue again at its meeting in September.