December 2, 2009 > Tighter regulation of dental and restaurant waste
Tighter regulation of dental and restaurant waste
By Dustin Findley
"The ordinance's purpose is to support the creation of a dental, mercury amalgam capture program (for fillings) and to revise the City's existing requirements governing disposal of fats, oil and grease to the City sewer system," explained Principal Engineer Kathleen Phalen to Council.
Dental waste is one of the largest sources of mercury in the wastewater stream.
In 2007, state regulatory agency the California Regional Water Quality Control Board - San Francisco Bay Region ("Board") decided to regulate dental waste throughout the Bay Area. Each wastewater treatment plant that discharges into San Francisco Bay must implement the Board's program when its five-year discharge program falls due for renewal.
The San Jose/Santa Clara Water Pollution Control Plant, to which Milpitas sends its wastewater, must implement the dental program in 2010. Milpitas must support it. To do so entails amending Milpitas' sewer ordinance and participating in this program.
Separated, mercury dental fillings are treated as hazardous waste. Waste and sludge from the drilling of teeth and other treatment is not captured in their entirety. Such substances find their way to the sewers via the chair-side traps in dental surgeries.
The program will require dentists, who deal with mercury amalgam fillings, to apply for a five-year permit from the San Jose treatment plant. They must also install an amalgam separator (costing around $752,000) to intercept the waste stream from the chair-side traps, implement mercury-reduction best management practices, such as maintenance of traps, staff training and correct storage of materials, and submit an annual compliance report to the San Jose treatment plant staff.
The treatment plant will send out notices of workshops for dentists in January 2010. A workshop in Milpitas is anticipated for January 22, 2010. Permit applications will be available in February and should be returned in March 2010.
Dentists will be required to install their amalgam separators by July and obtain certification from October to December 2010.
The Milpitas municipal code already addresses fats, oil and grease. In the summer, the City adopted a sewer-system management plan with a lipids-control component, as required by State law. The amendment revises the language.
Fats, oils and grease can cause sewerage to back-up into residences and businesses. City maintenance crews must then perform additional sewer flushing and cleaning.
The revisions seek to improve the ordinance's definitions and update the installation, cleaning and maintenance requirements for grease-removal devices or grease traps to ensure businesses, such as restaurants, meet requirements. Businesses must also keep a maintenance log for their equipment.
All cities using the San Jose/Santa Clara treatment plant must join the same program as Milpitas. The Board's directive applies to all treatment plants that discharge directly to the Bay. San Francisco Public Utilities Commission, East Bay Municipal Utilities Division, Palo Alto and Central Contra Costa have already implemented the program.
Ultimately, the authority for these regulations comes from the Federal Clean Water Act and the regulations implementing the act come through the US Environmental Protection Agency (EPA).
Council voted to introduce the ordinance. It will be brought back to council for adoption on December 1 and become effective 30 days later.