ĢEPA

Region 10	Alaska

Outreach and Community Relations	Idaho

1200 Sixth Avenue, ECO-081	Oregon

Seattle, Washington 98101	Washington

June 19, 1998

Superfund Update

Tulalip Landfill Superfund Site

Marysville, Washington

Landfill Design Complete, Construction to Begin

In May 1998 the U.S. Environmental Protection Agency (EPA), in conjunction with Waste Management
Inc., and the Tulalip Tribes finalized the design for the cleanup of the Tulalip Landfill. Mobilization for
construction started in June. The design is summarized below. If you have questions, want more
information about the design, or would like to request a meeting with EPA to learn more about the
design, please contact EPA. Contacts are listed at the end of this fact sheet.

The Problem and Selected Remedy

The dominant contamination problem at the
Tulalip Landfill Site is from rainwater that soaks
through the waste materials, becomes
contaminated and then runs into the Snohomish
River Estuary including Ebey Slough, Steamboat
Slough, and nearby wetlands. Contaminants
include: arsenic, chromium, copper, lead,
mercury, nickel, zinc, ammonia, heptachlor,
aldrin, DDT and Polychlorinated biphenyls
(PCBs). EPA selected a geosynthetic landfill
cover as the remedy for the problem in its March
1996 Interim Record of Decision (ROD).

Features of the Design

Major features of the design include:

Construction of a low hill

A low hill will be constructed on the currently flat
landfill. The hill will provide a slope for the
rainwater to run down, and off, the site. It will
reach about 23 feet above the surrounding land
at it's highest point. The hill will slope to the
edge of the site from the high point at grades of
2.5% (higher on the hill) and 2.2% (lower on the
hill). A 2.5% grade rises IVz feet over the length
of a football field (100 yards), a 2.2% grade rises
about 6V2 feet over the length of a football field.

Construction of the hill will require transport of
clean fill material from off of the site that will
increase local road traffic from time to time.

Geosynthetic Cover System

The hill will be covered with a geosynthetic
cover. The cover will consist of a 12 inch

foundation of gravel material, a layer of thick
plastic, a plastic mesh material, a fabric layer
and a 12 inch layer of soil. The cover will be
planted with appropriate vegetation such as
grasses and shrubs. The cover will prevent
virtually all rainwater from soaking into the
contaminated waste and producing leachate,
the name of the resulting contaminated liquid.

Once the cover is constructed, leachate seeps
are expected to dry up within about two years.
Besides drying the seeps the cover will also help
protect human health and the environment by
preventing people, animals and plants from
directly contacting the contaminated landfill
wastes.

Rainwater collection

A system will be constructed to collect and
channel the rainwater that runs-off the cover
and discharge it into the Snohomish River
Estuary and the Sloughs.

Gas Collection

Because waste in the landfill will generate
potentially flammable or noxious gases that
could damage the cover, a system to safely
collect the gases will be constructed. If
necessary to comply with air pollution control
requirements, the landfill gases will be treated
before they are released.

Perimeter Berm

A berm will be constructed around the perimeter
of the landfill to protect and anchor the hill and
cover.


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Tulalip Landfill - Page 2

Road System

A road system will be constructed on the
landfill to provide access for construction
and operation and maintenance.

The design also includes

monitoring of leachate seeps and
release of gas from the landfill to
ensure that landfill contaminants are
adequately contained;
measures to ensure the integrity
of the cover;

provisions for the operation and
maintenance of the site; and
the creation of an Environmental
Buffer Zone on the edge of the
landfill that may only be used for
passive recreation activities such as
walking, and will be managed to
benefit wildlife and protect the
cover.

Cost and Duration of the Project

Construction of the remedy is expected to
cost about $20 million and will take about
two years.

Construction Plans for this Year

This summer and fall construction will focus
on:

-	establishing a staging area near the
eastern border of the site;

-	filling, grading and covering of the
northeast part of the site; and

-	constructing the perimeter wall around a
portion of the site.

BACKGROUND

The 147-acre Tulalip Landfill is located on
North Ebey Island on the Tulalip Indian
Reservation. The landfill lies between Ebey and
Steamboat Sloughs and is surrounded by
ecologically sensitive wetlands. The Tulalip
Tribal Corporation initially leased the land to
the Seattle Disposal Company in 1964.
Between 1964 and 1979, an estimated three to
four million tons of mixed commercial and
industrial waste was deposited in the landfill.

Because of ecological and human health
concerns, the Tulalip Landfill was proposed for
inclusion on the National Priorities List (NPL)
of hazardous waste sites in July 1991. The site
was added to the NPL in April 1995.

EPA signed an Administrative Order on
Consent with some of the major Potentially
Responsible Parties to conduct an investigation
of contaminants at the site, called a Remedial
Investigation, and a study of possible solutions to
contain the landfill wastes, called the Source
Area Containment Feasibility Study in August
1993.

Sampling efforts indicate that leachate
(contaminated water) leaving the site exceeds
marine water quality standards and criteria for
heavy metals and other contaminants including
arsenic, chromium, copper, lead, mercury,
nickel, zinc, ammonia, heptachlor, aldrin and
DDT. Polychlorinated biphenyls (PCBs) have
also been found in leachate seeps.
Contaminated groundwater and leachate flow
directly into sensitive wetlands that surround
the site, and into sloughs connected with the
Snohomish River and Puget Sound. Sediments
and soils near the leachate seeps contain many
of the same contaminants at concentrations
higher than is considered to be protective of the
health of people and the environment.

EPA's Record of Decision (ROD) for the site,
which describes the preferred remedy for the
site was established in March 1996. This fact
sheet describes the final design for that remedy.


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Tulalip Landfill - Page 3

ADDITIONAL INFORMATION

If you are interested in learning more about the Tulalip Landfill Superfund Site or the Superfund process,
EPA encourages you to review the Tulalip Landfill Superfund Site Administrative Record. The
Administrative Record contains copies of the Remedial Investigation Report, the Source Area
Containment Feasibility Study, the Risk Assessment for Interim Remedial Action, the Community
Relations Plan, the Proposed Plan, the Record of Decision (which includes the Responsiveness
Summary) and other materials related to the site. Copies of the Administrative Record are available for
review at the following locations:

The Marysville Public Library	EPA Records Center

6120 Grove	1200 Sixth Avenue, 7th Floor

Marysville, Washington	Seattle, Washington

Please call and set up an appointment if you would like to review documents at the EPA Records
Center. No appointment is needed to review the information at the Marysville Public Library.

To request that documents be mailed to you, for further information, or to request a meeting
with to learn more about the design of the Tulalip Landfill Site, please call EPA.

TDD Device (for the hearing or speech impaired) (206) 553-1698

Additional services can be made available on request to persons with disabilities.

Copies of this Fact Sheet and other information about the Tulalip Site
are available from the EPA Region 10 Internet WEB site at:
http://epainotes1.rtpnc.epa.gov:7777/r10/cleanup.nsf/webpage/Tulalip+Landfill

EPA's Toil-Free Number in Alaska, Idaho, Oregon and Washington is:

1- (800) 424-4372
Ask the attendant to transfer your call as appropriate:

Loren McPhillips, Project Manager

Robert Drake, Community Relations Coordinator

EPA Records Center

(206) 553-4903
(206) 553-4803
(206) 553-4494

For general information about EPA's activities go to our WEB homepage

www.epa.gov


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