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APPLYING TO THE PEC: A CASE HISTORY - A WALK THROUGH THE PROCEDURE FOR APPLYING FOR EQUIVALENCY USING A RECENT CANDIDATE AS A TRUE EXAMPLE.
Citation:
REIMERS, R. S., K. B. FITZMORRIS, AND J. E. SMITH. APPLYING TO THE PEC: A CASE HISTORY - A WALK THROUGH THE PROCEDURE FOR APPLYING FOR EQUIVALENCY USING A RECENT CANDIDATE AS A TRUE EXAMPLE. Presented at Pre Conference Workshop: New Class A Processes and Regulatory Acceptance: Water Environment Federal Specialty Conference on Residuals and Biosolids Management, Covington, KY, March 12 - 15, 2006.
Description:
The USEPA's Pathogen Equivalency Committee (PEC) is entrusted by its Office of Water to critically evaluate innovative and alternative sludge disinfection processes and make recommendations about their Process to Significantly Reduce Pathogens (PSRP) or Process to Further Reduce Pathogens (PFRP) equivalency. To make such a recommendation the PEC works closely with the permitting authority and the applicant to develop a quality assurance project plan for demonstrating the effectiveness of the new technology. When followed, such a plan ensures that the results submitted in support of a process are statistically significant. The PEC further provides oversight of the demonstration, rigid review of the data developed, and helps with preparation of an operation and maintenance manual detailing conditions of the equivalency. Information on the new technology is made available to permitting authorities. The applicant must be able to clearly define his/her process and explain the mechanism(s) it uses to accomplish disinfection. Typically an applicant must be able to show that his/her process is capable of accomplishing a two log reduction in viable helminth (Ascaris) ova and a three log reduction in enteric viruses. Since this demonstration is usually done on a laboratory scale, during the laboratory research phase the applicant is encouraged to find surrogates for enteric viruses and viable helminth ova to use in plant scale testing.
Bioset applied to the PEC in December 2002, provided various clarifications to its application in April 2003, conferenced with the PEC on July 15, 2003 and received a site specific equivalency recommendation for Kingwood, Texas in July 8, 2004. Bioset's equivalency holds when the process operates as follows: 1) The sludge is held at a temperature of 55°C or greater for a minimum of 25 minutes; 2) The solids content of the sludge being treated is in the range of 6% to 35%; 3) The ammonia content in the reactor is 1% (10,000 mg/L) on a volume basis; 4)The pressure in the reactor is 30 psi; 5) The amount of lime added is 0.55 to 0.75 lbs. lime to 1 dry lb. of sludge; 6) The amount of acid added is 8 to 10 lbs. per dry ton of sludge, and; 7)The pH is greater than 12.
As can be noted above, factors affecting the disinfection include: temperature, solids concentration, ammonia, pressure, and pH. Bioset is currently developing data at several sites in Louisiana and Florida with the object of obtaining a recommendation of national equivalency. Bioset treated sludges are used on a variety of crops.