EXPANDING A PUBLICLY OWNED TREATMENT PLANT
TO ACCOMMODATE INDUSTRIAL WASTEWATERS
A CASE HISTORY
Clement A. Vath, Manager
Concept Engineering Department
Roy F. Weston, Inc.
Wilmette, Illinois     60091
Ranjit K. Advani, Group Manager
Environmental and Energy Services
Hoff-Weston
Cleveland, Ohio   44106
INTRODUCTION
Background of the Problem
The ten major industrial contributors to the municipal wastewater treatment system
of a major mid-western community became concerned when the City's consultant took
a conventional approach to planning for and designing the upgrading of  the existing
wastewater treatment plant to improve performance and to increase capacity.    The ten
companies-two pulp and paper mills, six paper mills, one   milk processing plant and
one foundry—contribute 65% of the wastewater flow, 75% of the BOD load and 82%
of the total suspended solids load to the joint treatment facility.    The companies formed a committee to present a unified position of concern to the city fathers, public works
committee and the waste treatment plant superintendent.   Despite the predominant
industrial character of the treatment plant influent, the committee failed to develop
concern on the part of the elected officials and the City's consultant continued to work
on a design based on criteria in "Recommended Standards for Sewage Works, Great
Lakes-Upper Mississippi River Board of State Sanitary Engineers," generally referred to
as the Ten-State Standards.    Consequently, the companies retained Roy F. Weston, Inc.,
to develop design parameters tailored to the specific needs of the industrial-dominated
wastewater and to make maximum use of the existing treatment facilities in the design
of the proposed upgraded plant.
Objectives of the Industry Study
Industry's major concerns were:    (a) The use of conventional domestic waste treatment design parameters for a predominantly industrial wastewater flow; (b) The failure
to undertake pilot plant studies to demonstrate whether the proposed expanded and
modified plant could meet the required discharge quality standards; (c) The failure to
recognize wastewater variability in developing design loadings for the plant, coupled
with the use of undocumentable flows and loads for wastewater components and for
infiltration and inflow in developing the design basis; and (d) The excessive cost of the
"textbook" (Ten-State Standards) approach to the solution of the problem.
Consequently, the companies called on Weston to independently determine and
develop:   (a)   The wastewater flows, loads and variability characteristics from the