Section 9. TRANSPORTATION WASTES
RESOLUTION OF AN INDUSTRY'S OILY WASTE PROBLEM
Richard P. Cardile, Project Manager
Howard, Needles, Tammen, & Bergendoff
Chicago, Illinois 60606
Robert E. Fronczak, Environmental Engineer
Chicago, Milwaukee, St. Paul & Pacific Railroad
Chicago, Illinois 60606
The Chicago, MUwaukee, St. Paul & Pacific Railroad undertook a rigorous design and
construction program in 1978 and 1979 to bring their existing treatment facilities at the
Milwaukee Shops into compliance with their NPDES permit and local sewer ordinances.
The new plant was placed in operation in August 1979 and has reduced local sewer service
charges for the portion of pretreated wastewater discharged to the sanitary sewer system
and met NPDES permit levels for the portion of flow discharged to the river.
In late 1977 the raUroad contracted with a consulting firm to study alternative treatment
solutions for their facilities and to develop final design plans and specifications for a new
wastewater treatment plant. The new treatment facilities were required to solve two separate
waste treatment problems; first the stormwater runoff from the shops that is discharged to
the river having high oil and grease (O&G) and total suspended solids (TSS) levels and
second, an industrial process flow that is discharged to the sanitary sewer system also having
high O&G and TSS levels.
The railroad performs heavy and routine engine maintenance and railcar reconstruction
at the shops, which are located in the Menomonee River Valley west of downtown Milwaukee, WI. Diesel locomotives are cleaned routinely inside the shops and outside by an
automatic locomotive washer when weather permits. Wastewater is generated by the locomotive washer, shop maintenance operations and includes domestic waste from approximately 900 shop employees. The combined wastewater is high in O&G, TSS and may be
either acidic or alkaline. Waste oil is in two forms, free and emulsified. Free oil is generated
from routine engine maintenance and limited unavoidable spillage during lube oil changes
and fueling operations; and emulsified oil is generated from the locomotive washer and
detergent washing of locomotive parts at various points throughout the shops. At railroad
engine terminals with diesel repair shops, about half the oil is free oil and half is emulsified
[11.
Stormwater runoff from concrete pads, paved driveway and parking areas and locomotive
"ready" tracks has a high oil and solids concentration due to the exposure of the area to
railroad traffic and maintenance activities. Track pans, located in fueling and sanding areas,
collect runoff to prevent contamination of ballast and subgrade from spilled oil. Therefore,
runoff must be treated for oil and solids reduction prior to discharge to the Menomonee
River in order to meet NPDES permit requirements.
Industrial wastewater and stormwater runoff are collected by separate sanitary and storm
sewer systems. The shops are served by sanitary sewers conveying all domestic wastewater
and partially pretreated industrial wastewater to the city's sewer system. Previous pretreatment facilities consisted of small gravity-type oil separators located at specific shops
known to have high oil levels in the discharge.
Stormwater runoff was captured in three separate storm sewer systems which previously
discharged to the Menomonee River at three outfall locations. Two of the three discharges
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