WASTEWATER TREATMENT DIVISION
COMPOSTING

In 1994 the City of Florence began a compost operation to eliminate wastewater sludge waste.  Compost is a mixture that consists largely of decayed organic matter and is used for fertilizing and conditioning land.  The compost material has been given the title "Flo-Gro" and is used in many of the City's flower beds.

The operation is regulated by the South Carolina Department of Health and Environmental Control.  Listed below are the specific permit conditions, which must be met prior to distribution:

• Only non-hazardous sludge solids that are generated at the Florence/Main Wastewater Treatment Plant (WWTP) and treated to Class A – Excellent Quality (EQ) standards by composting may be used in the distribution and marketing program.

• Compost Sludge must achieve the Process to Further Reduce Pathogens (PFRP).  The process of monitoring fecal coliform in the sewage sludge shall be monitored and cannot exceed 1000 Most Probable Number per gram of total solids.

• Composted sludge must maintain a temperature of 55 degrees Celsius or higher for three consecutive days.  Once this temperature is met the sludge temperature is maintained at 40 degrees Celsius.  This process is completed in order that the sludge meets Vector Attraction Reduction (VAR).

If the PFRP and/or the VAR requirements are not met the compost may not be given away.

Compost is monitored for the following metals on a quarterly basis:

• Arsenic

• Mercury

• Cadmium 

• Nickel

• Copper   

• Selenium

•  Lead

•  Zinc 

Compost is available to the public Monday through Friday from 8:00 a.m. until 4:00 p.m. for pick up.