£EPA

This Fact Sheet

Will Tel I You About

•	the site history

•	the new ground-water cleanup
plan

•	why the ground-water cleanup
plan is being modified

•	how you can get more
information about the site

30r more detailed

information,

site-related docu-
ments may be re

viewed at.

Mill Road Library

United States
Environmental Protection
Agency

Office of Public Affairs
Region 5

77 W. Jackson Blvd.
Chicago, Illinois 60604

Illinois, Indiana,
Michigan, Minnesota,
Ohio, Wisconsin

U.S. EPA Announces Changes in

Moss-American Superfund Site
Cleanup Plan

Milwaukee, Wisconsin	May 1997

Introduction

The U.S. Environmental Protection
Agency (U.S. EPA) has modified the
remedy to clean up contaminated
ground water at the Moss-American
Superfund Site in Milwaukee, Wis-
consin. This fact sheet explains the
significant differences in the ground-
water cleanup plan and why the
modifications are necessary. It is a
summary of the official document
entitled "Explanation of Significant
Differences for the Moss-American
Site, Milwaukee, Wisconsin," which
is available for review at the infor-
mation repository for the site (see
page 3). U.S. EPA plans to announce
additional proposed changes to the
soil and sediment elements of the
cleanup plan in the near future.

The ground-water cleanup plan is
being modified to test a new and
potentially more effective method
of ground-water cleanup. The modi-
fied cleanup plan changes the way
contaminated ground water is col-
lected. Field investigation done in
1994 found more free-product creo-
sote than previously known. The
modified approach should be a more
effective method of collecting and
removing the free-product creosote
than the original plan. The presence
of more creosote than anticipated
may increase the amount of time
necessary to clean up the contami-
nated ground water.

Background and Site
History

The 88-acre Moss-American
Superfund Site includes the former
location of the Moss-American creo-
sote facility, several miles of the
Little Menomonee River (a portion
of which flows through the eastern
half of the site) and the adjacent
floodplain. The site is located in the
northwest corner of the City of Mil-
waukee, at the southeast corner of

the intersection of Brown Deer and
Granville Roads. Approximately 65
acres of the site are undeveloped
Milwaukee County park land. The
remaining 23 acres are owned by the
Union Pacific Railroad (formerly the
Chicago and North Western Railroad)
and are used as an automobile and
light truck transport and storage area.

In 1921, the T. J. Moss Tie Company
established a wood preserving facil-
ity west of the Little Menomonee
River. The plant preserved railroad
ties, poles, and fence posts with creo-
sote, a mixture of numerous chemi-
cal compounds derived from coal tar.
From 1921 to 1971, the facility dis-
charged wastes to settling ponds that
ultimately discharged to the Little
Menomonee River. These discharges
ended when the plant diverted its
process water discharge to the Mil-
waukee sanitary sewerage system in
1971. Kerr-McGee Chemical Corpo-
ration purchased the facility in 1963
and changed its name to Moss-Ameri-
can. The name was changed again in
1974 to Kerr-McGee Chemical Cor-
poration—Forest Products Division.
Production at the facility ceased in
1976.

Contamination at the site was first
reported in the late 1960s. In 1973,
approximately 5,000 feet of the Little
Menomonee River between the site
and Bradley Road were dredged.
Kerr-McGee cleaned out eight former
settling ponds and dredged about
1,700 feet of the Little Menomonee
River to remove creosote-contami-
nated soil and sediment. In 1978, the
facilities were razed and some oil-
saturated soil was excavated and dis-
posed off site.

In 1983, the facility was placed on the
U.S. EPA's National Priorities List
(NPL), a roster of sites eligible for
Superfund cleanup. Following dis-
cussions with potentially responsible
parties (PRPs—those who owned,

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Extent of Ground-water
Contamination

Area of Free-product •*-
Creosote



Figure 1. Site Map

operated, or brought waste to the
site), U.S. EPA determined it would
conduct a Remedial Investigation/
Feasibility Study (RI/FS) at the site.
The RI/FS, which determined the
nature and extent of on-site contami-
nation and methods for cleaning it
up, was completed in 1989. U.S EPA
held a public meeting in 1990 on the
RI/FS results and the recommended
cleanup plan. Detailed information
may be found in the site information
repository.

U.S. EPA announced its cleanup plan
in a document called a Record of
Decision (ROD) in 1990. After select-
ing its cleanup plan, U.S. EPA, Wis-
consin Department of Natural Re-
sources (WDNR), and the PRPs signed
an agreement to clean up the site.
This agreement called for Kerr-McGee
Chemical Corporation to implement
the remedy described in the ROD.

Recent Site Activities

In 1994, Kerr-McGee Chemical Cor-
poration verified the presence and
extent of free-product creosote in soil
about 10 feet below ground surface.
This work was done as part of the
agreement among Kerr-McGee, U.S.
EPA, and WDNR. Kerr-McGee found
enough creosote for U.S. EPA to give
priority to removing it before imple-
menting the ground-water collection/
treatment plan. Kerr-McGee installed
seven extraction wells to pump the
creosote from below ground to an
on-site storage tank (see Figure 1).
During the 1995-96 operating season,
about 3,100 gallons of free-product
creosote were collected and removed

from the site. This extraction system
can only be operated seasonally, as it
was not designed to operate in freez-
ing conditions.

Explanation of Significant
Differences

Additional investigation provided a
better understanding of site condi-
tions. There have been advances in
ground-water cleanup technologies
that are appropriate for conditions at
the Moss-American site. Therefore,
U.S. EPA proposes to change the
original ground-water collection and
treatment remedy. The 1990 remedy
included collecting contaminated
ground water in drains installed par-
allel to the west side of the Little
Menomonee River. A vertical barrier
would have been installed between

the collection drains and the river to
prevent contaminated ground water
from reaching the river. The ground
water would have then been pumped
to an oil-water separator. The oil
would have been incinerated and the
water would have been forced
through tanks containing activated
carbon. Activated carbon is a spe-
cially treated material that attracts
contaminants. After treatment, the
ground water would have been dis-
charged to the Milwaukee Metropoli-
tan Sewerage District sanitary sewer
system or to the Little Menomonee
River.

The new ground-water remedy is
known as a funnel and gate system.
The funnel and gate system will redi-
rect ground-water flow by driving
sheet piling (the funnel) into the soil

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What is free-product creosote?

"Free-product" is a term used to describe a contaminant that has
not dissolved into ground water or soil but is found in the
environment essentially intact. At the Moss-American site, a pool
of free-product creosote is floating within a plume of contami-
nated ground water (see Figure 1). At this site, the free product is
an oily mixture of coal-tar creosote mixed with a fuel oil carrier
solvent that is in contact with the shallow ground water at the
site. When the free product is removed, it is typically mixed with
ground water to create a liquid mixture of water, fuel oil, and
coal-tar creosote. Free-product creosote poses a challenge to
ground-water management because it acts as a continuing source
of ground-water contamination and it can move in different
directions or at different speeds than the ground water around it.

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underneath the contaminated aqui-
fer (see Figure 2). Sections of piling
would be interconnected and sealed.
Ground-water flow would be directed
to engineered soil mixtures placed in
gaps (the gate) in the sheet piling. As
the ground water moves through the
gates, bacteria in the soil mixtures
will break down the contaminants.
Air and nutrients would be injected
into the gates to increase the amount
of naturally occurring bacteria in the
soil mixtures, thereby increasing the
amount of ground-water contamina-
tion the bacteria can break down. To
prevent free-product creosote from
entering the gates and clogging the
system, the PRPs will install sumps or
collection wells west of the gates that
will allow the creosote to be pumped
to an on-site storage tank. Two rows
of sheet piling (funnel and gate sys-
tems) would be constructed. The first
system would be placed near the
boundary between Railroad and
County property. The second system
would be just west of the Little
Menomonee River. Several ground-
water monitoring wells would also
be installed to monitor the effective-
ness of the funnel and gate systems.

The construction cost for the funnel
and gate system is nearly identical to
the more conventional ground-water
treatment approach in the 1990 ROD.
However, operation and maintenance

costs are substantially less than those
costs for the previously planned
cleanup method. Because the large
quantity of free-product creosote may
require considerably more time to
collect and treat ground water than
anticipated in 1990, reduced opera-
tion and maintenance costs become
more important.

The PRPs will construct a pilot funnel
and gate system at the site prior to
full-scale implementation. During the
pilot project, designers will monitor
the effectiveness of the funnel in
capturing the contaminated ground-
water plume and directing it toward
the gates. The designers will also
monitor the effectiveness of the gates
in breaking down ground-water con-
taminants. The pilot project could
take 1 to 2 years. Should problems
arise such as inadequate capture of
contaminated ground water or insuf-
ficient removal of ground-water con-
taminants, U.S. EPA and WDNR will
develop other remedies to clean up
ground water, such as additional
sumps, trenches, or gate covers.

At this time, U.S. EPA does not pro-
pose to modify the site's ground-
water cleanup goals. After consider-
ing new information, U.S. EPA and
WDNR believe this change:

• protects human health and the
environment;

•	complies with appropriate state
and federal requirements; and

•	is more cost effective than the
original ground-water remedy.

What's Next?

Design of the pilot funnel and gate
system project is scheduled to be
completed this year. U.S. EPA and
WDNR will monitor the results of
funnel and gate system testing and
will provide a summary of their find-
ings before making a final decision
on full-scale implementation. In the
meantime, the PRPs will continue
collecting free-product creosote.

Additional Information

Anyone interested in learning more
about the Explanation of Significant
Differences is encouraged to review
the information repository for the
Moss-American Site. The information
repository is located at the Mill Road
Library, 6431 N. 76th Street, Mil-
waukee. An administrative record
containing information upon which
U.S. EPA based its decisions has also
been placed at the library. Post-ROD
documents are included. For addi-
tional information on the Moss-Ameri-
can Site, please contact:

Susan Pastor

U.S. EPA Community
Involvement Coordinator
(312) 353-1325

pastor.susan@epamail.epa.gov

Russell Hart

U.S. EPA Remedial Project
Manager
(312) 886-4844
hart.russell@epamail.epa.gov

U.S. EPA Region 5
77 West Jackson Boulevard
Chicago, IL 60604
Toll Free 1-800-621-8431

Gary Edelstein
WDNR Project Manager
Box 7921

Madison, WI 53707
(608) 267-7563

edelsg@dnr.state.wi.us

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Mailing List Additions

If you did not receive this fact sheet in the mail, you are not on the mailing list for the Moss-American Superfund
Site. To add your name, or to make a correction, please fill out this form and mail it to Susan Pastor at the address
below.

Susan Pastor

U.S. F.PA Region 5

Office of Public Affairs (P-19J)

77 West Jackson Blvd.

Chicago, Illinois 60604

Name.

Address.

Affiliation

Phone (Daytime)

(Evening)

I	I

Once you are on the mailing list, you will automatically receive information from. U.S. EPA regarding the Moss-American Site.

oEPA

U.S. Environmental Protection

Agency

Region 5

Office of Public Affairs (P-19J)
77 W. Jackson Blvd.

Chicago, Illinois 60604

ADDRESS CORRECTION REQUESTED

FIRST CLASS

ATTENTION: Modified Moss-American Site Cleanup Pla

\ I

This fact sheet is printed on paper made of recycled fibers.

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