Methodology of a Regional
Industrial Wastewater Audit
LUIS J. THIBODEAUX, Associate Professor
DEE MITCHELL, Assistant Professor
College of Engineering
University of Arkansas
Fayetteville, Arkansas 72701
BRUNO KIRSCH, JR., District Engineer
Arkansas Health Department
Fayetteville, Arkansas 72701
INTRODUCTION
A comprehensive water pollution control planning grant was awarded to the Northwest Arkansas Regional Planning Commission in 1971. A portion of the program was to
quantify and catalog the industrial wastewater sources in the basin study area. This
basin contains approximately sixteen hundred squares miles, three river basins and a
population of 140,000. The region has a strong and growing economy with high employment. Agricultural employment is down, but production is growing. Industrial employment is growing rapidly. This paper presents the magnitude, procedures, results, and
validity of the industrial wastewater audit for the basin study area. This presentation
follows closely the original work (13) however portions have been rewritten and much
data has been excluded. The result here is essentially a guide in methodology presented
as a case study.
GENERAL ASPECTS OF THE SURVEY
Area and Content
The primary objective of the industrial wastewater survey is to obtain a definitive
picture of the quantity and quality of wastewater in NW Arkansas. A total of forty-five
industrial wastewaters were surveyed and sampled during the period of June 1971 to July
1972. Table I shows the magnitude of the survey with respect to the principal water-using
industries and with respect to the total industries. Only 21 percent of the industries in
NW Arkansas were studied, however, this was 52 percent of the major water based
industries. A water based industry is defined (for this study) as one in which water is a
necessary and significant resource for operation of the industrial process other than
sanitary sewer facilities.
Thorough analysis of every industrial plant in the planning area was not the aim,
however, the survey did provide sufficient information on typical industry classifications of
wastes specific to Northwest Arkansas. Table II gives the Standard Industrial Classification
(SIC) and the number in each class surveyed for critical industrial wastewaters. SIC No.
201 and No. 203 constitute the bulk of the critical industrial wastes and the bulk of the
wastewater. These two groups are predominately poultry processing and vegetable canning.
Methodology of Conducting Survey
A wastewater survey is essentially a material balance involving water and the various
pollutants it contains plus the nature of the process and various production measures. The
material balance can be performed by measuring water or wastewater flow rates and
concentrations of pollutants in the water. From this information representative unit flows
and loads can be obtained for each industry type. The details of the survey tehniques follow:
1. Consulted directories, industrial listings, area planners, city waterworks personnel,
etc.,   and   formulated  a   list   of  the   principal  "wet"  industries   in   the  area.
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