86    IMPROVEMENTS TO A SEPTAGE REGULATION
PROGRAM FOR A
MAJOR MIDWESTERN CITY
Dale R. Bertelson, Engineer
James M. Montgomery Consulting Engineers, Inc.
Los Angeles, California 90248
INTRODUCTION
The City referred to in this paper operates two Advanced Wastewater Treatment (AWT) Facilities
which serve approximately 700,000 people in two counties. Both AWT's include the processes of
nitrification and ozone disinfection following conventional primary sedimentation and bioroughing
trickling filter processes. In addition to those served by the treatment facilities, there are approximately 300,000 additional people in the service area who utilize septic tanks as their means of
wastewater treatment and several hundred new septic tanks are approved for installation each year.
One of the two AWT's has been the approved disposal site for the area's septage for many years.
Independent haulers have been, and continue to be, allowed to dump the contents of their trucks at
the influent end of this facility. Historically, the septage haulers had received very little attention and
could be considered essentially self-regulating. Little consideration had been given to the contents of
the tank trucks, the origin of the load or the potential for treatment plant upset created by the
acceptance of septage.
With the implementation of an Industrial Pretreatment Program, it became necessary for the City
to address the potential problems associated with the disposal of septage at the AWT. In addition,
industrial wastewater disposal was now addressed under the "domestic sewage exclusion" and "permit
by regulation" portions of RCRA, forcing the City to take a closer look at it's septage disposal
practices.
As a result, a study of the City's existing septage regulation program was initiated in 1982. The
purpose of this study was to investigate a means of effectively regulating the septage haulers, and a
way to protect the AWT from upsets and the City from liability for accepting a RCRA hazardous
waste.
Once the study began, it became apparent that there were other issues to be resolved in addition to
the regulatory considerations. These issues included the following: 1) the City had no data base for
septage; 2) the rates charged for septage disposal appeared to be too low; 3) the existing system for
billing and tracking haulers was inadequate; and 4) the city was being asked to accept hauled wastes
which were neither domestic septage nor RCRA wastes and for which no clear guidelines for screening
or billing existed. This chapter discusses each of these issues and summarizes the methods used and the
results achieved in attempting to resolve these issues.
SCOPE OF THE STUDY
Data Base Generation
The primary area of investigation of the study involved the generation of a data base which could be
used to evaluate the impact of septage on the treatment processes and to determine and assess the
extent of any existing regulatory problems. In order to compile such a data base, samples of septage
were collected from each truck entering the facility to dump beginning in March 1982. Daily composites were made from these samples and the composites were then analyzed for Biochemical Oxygen
Demand (BOD), Total Suspended Solids (TSS), Ammonia Nitrogen (NH3-N) and pH. The sampling
program was discontinued in 1983, but resumed in 1984 and continued through 1987. The analytical
results of the sampling program for these conventional pollutants are summarized in Table I. Data
collected in 1982 has been omitted from this table due to the fact that maximum allowable sample
holding times for some of the parameters were often exceeded before the samples were analyzed.
43rd Purdue Industrial Waste Conference Proceedings, © 1989 Lewis Publishers, Inc., Chelsea, Michigan 48118.
Printed in U.S.A.
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