San Luis Obispo County supervisors on Tuesday will take up the controversial issue of using sewage sludge as fertilizer on farmland.
An interim ordinance governing the use of sludge, also called biosolids, in the county will expire in a year. Dr. Penny Borenstein, the county’s health officer, is asking supervisors to extend the interim ordinance three more years or replace it with a permanent one.
The use of sludge is controversial because it can contain lead, mercury and other toxic heavy metals that are not removed in the sewage treatment process. The county’s rules are so restrictive that no application of more than 5 cubic yards of sludge has occurred since the temporary rules took effect in 2004.
On Tuesday, supervisors will consider three options. One is to extend the current ordinance until March 2017. The second is to make the existing ordinance permanent. The third is to move forward with a new ordinance that is being developed.
County staff is recommending that the interim ordinance be extended in order to allow more time for development and environmental review of a new ordinance. It would also allow time for several government studies into the environmental effects of sludge to be completed.
These studies are looking at not only the accumulation of metals and toxins, but also are examining the potential health effects of pharmaceuticals, over-the-counter medications and personal care products in biosolids, according to a health agency staff report.
The sewage sludge controversy in the county began in 1998 when a waste company sought to apply as much as 50,000 tons a year on ranchland near San Miguel. Public outcry stopped that proposal, and the county took over regulating the use of sludge from state water officials.
The county adopted its interim ordinance in 2004 and has extended it several times. Efforts to develop a permanent ordinance have been hindered by the estimated $200,000 cost to do an environmental review.
County staff approached operators of wastewater treatment plants to see whether they would be interested in sharing the cost of doing the environmental review; however, the operators of those facilities said they are concerned that a new ordinance would be too restrictive to warrant sharing in the cost.
The sludge hearing is set for the supervisors’ morning agenda.