United States
Environmental Protection
Agency
Solid Waste
and Emergency Response
(OS-305)
EPA/530-SW-91-089
March 1993
Criteria for Solid Waste
Disposal Facilities
A Guide for Owners/Operators

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 Owners/operators
    must set up a
  system to ensure
   that hazardous
wastes are kept out
     of municipal
        landfills.
To make waste management more
effective, federal, state, tribal, and local
governments are adopting an integrated
approach to waste management. This
strategic approach involves a mix of
three waste management techniques: 1)
decreasing the amount and/or toxicity
of waste that must be disposed of by
producing less waste to begin with
(source reduction); 2) increasing
recycling of materials such as paper,
glass, steel, plastic, and aluminum, thus
recovering these materials rather than
discarding them; and 3) providing safer
disposal capacity by improving the
design and management of incinerators
and landfills.

Source reduction and recycling will
keep a lot of waste out of municipal
landfills, but we still need landfills. The
challenge is to make them safe in order
to protect our communities and our
environment—and that requires a
strong partnership of federal, state,
and tribal governments; industry;
and citizens.
                                                           EPA's continuing mission is to minimize
                                                           the risks from landfills. The criteria
                                                           described in this booklet are an
                                                           important part of this effort. They
                                                           establish minimum national standards
                                                           for landfill design, operation, and
                                                           management that will enhance landfill
                                                           safety and boost public confidence in
                                                           landfills as a component of a workable
                                                           integrated waste management system.

                                                                             >

                                                              ::*?•

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         This booklet summarizes the provisions of the U.S. Environmental
         Protection Agency's (EPA's) Municipal Solid Waste Landfill (MSWLF)
         Criteria. It discusses the major requirements of these regulations, who is
   required to comply and when, how the rule will be implemented and enforced,
   and where to obtain more information. States and Indian tribes are expected to
   adopt these federal standards and implement the regulations through their own
   permit programs. This booklet highlights the increased flexibility given to states
   and tribes that develop EPA-approved programs.

   This booklet provides only an overview of the federal regulations. Readers
   affected by them should refer to the actual regulations, which are published in
   Volume 40 of the Code of Federal Regulations, Part 258 (see the Federal Register,
   October 9,1991,56FR50978). The Agency encourages landfill owners/operators to
   work with their respective state or tribal authorities, since state
   and tribal programs may have different
   requirements.

   Although written primarily for
   owners/operators of municipal
   solid waste landfills, this booklet
   also will be useful for others,
   including state and tribal govern-
   ment officials, who are responsible
   for implementing the regulations.
Introduction
       The problems caused by municipal
       solid waste landfills have become
       a source of public concern in recent
years. As Americans have become more aware
of the potential threat to health and the
environment from toxic substances, they also
have become more concerned about the
generation and management of solid waste —
sometimes to the point of refusing to allow
new landfills near their homes. Americans
are generating more municipal solid waste
each year, but available landfill space is
declining. In 1990, Americans generated
over 195 million tons of municipal
solid waste, and the annual amount is
expected to increase to more than
220 million tons by 2000.

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The Purpose of These

Regulations

        Historically, landfills have been
        associated with some
        significant problems, including
ground-water contamination, which
partly explains the public's resistance to
new facilities.

Ground-water contamination.  Nearly
half the country's population draws its
drinking water from aquifers and other
ground-water bodies. Ground water
also is used extensively for agricultural,
industrial, and recreational purposes.
Landfills can contribute to the
contamination of this valuable resource
if they are not designed to prevent waste
releases into ground water or detect
them when they occur. Cleaning up
contaminated ground water is a long
and costly process and in some cases
may not be totally successful. Affected
communities often bear both the
cleanup costs and the expense of
providing other sources of potable
water. By adopting a philosophy of
prevention, the regulations' improved
design standards will protect ground
water.

Difficulties in  landfill siting. The
problem of managing the increased
volume of municipal solid waste is
compounded by rising public resistance
to siting new landfills. The regulations
are designed to ensure that new or
expanded landfills do not contaminate
. ground water and thus become
 community burdens. As a result, they
 protect the intrinsic value of ground
 water and can help avert the pressures
 associated with landfills that can drive
 down property values.

 Specific prevention measures written
 into the regulations include location
restrictions, operating and design
criteria, and requirements for final cover
and post-closure care. The regulations
also require ground-water monitoring to
detect any releases of contaminants from
landfills. Corrective action and financial
assurance provisions ensure immediate
and effective responses to such releases.
          Some Definitions Under

                the Regulations

   Municipal solid waste landfill (MSWLF): A discrete area
   of land or an excavation that receives household waste,
   and that is not a land application unit, surface
   impoundment, injection well, or waste pile, as those terms
   are denned in the law. (Household waste includes any
   solid waste, including garbage, trash, and septic tank
   waste derived from houses, apartments, hotels, motels,
   campgrounds, and picnic grounds.) An MSWLF unit also
   may receive other types of wastes as defined under
   Subtitle D of the Resource Conservation and Recovery Act
   (RCRA), such as commercial solid waste, nonhazardous
   sludge, small quantity generator waste, and industrial
   solid waste. Such a landfill may be publicly or privately
   owned. An MSWLF unit can be a new unit, an existing
   unit, or a lateral expansion (see definitions below).

   Existing unit: A municipal solid waste landfill unit that is
   receiving solid waste as of October 9,1993. Waste
   placement in existing units must be consistent with past
   operating practices or modified practices to ensure good
   management.

   Lateral expansion: A horizontal expansion of the waste
   boundaries of an existing unit; does not include expansion
   in the vertical dimension.

   New unit: Any municipal solid waste landfill unit that has
   not received waste prior to October 9,1993.

   Small landfill: A landfill serving a community that
   disposes of less than 20 tons of municipal solid waste per
   day, averaged yearly.

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Landfills receiving
 waste on or after
 October 9, 1993,
must comply with
  the regulations.
                   EPA has carefully considered the
                   impacts of the regulations on local
                   governments. Where possible, EPA has
                   written the regulations to allow
                   flexibility in both the technical
                   requirements and their implementation.
                   For example, the regulations provide
                   relief from the more costly requirements
                   for certain small landfills. Moreover,
                   states and tribes with EPA-approved
                   landfill permitting programs are given
                   the opportunity to provide considerable
                   flexibility in applying all major
                   components of the landfill criteria, so
                   that site-specific conditions can be
                   considered in such areas as design and
                   ground-water monitoring.
Who Is  Covered?

       The regulations apply to owners/
       operators of all municipal solid
       waste landfills that receive waste
on or after October 9,1993. Landfills
that stop accepting waste between
October 9,1991, and October 9,1993,
need only comply with the
requirements for final cover (see page
16). Landfills that stopped accepting
waste before October 9,1991, do not
need to comply with these regulations.

The regulations apply to landfills that
accept household waste, which means
any solid waste (including garbage,
trash, and sanitary waste in septic tanks)
derived from households (including
single and multiple residences, hotels
and motels, bunkhouses, ranger
stations, crew quarters, campgrounds,
picnic grounds, and day-use recreation
areas). They do not apply to units
(including landfills, surface
impoundments, waste piles, and land
application units) that accept only
industrial nonhazardous waste (e.g.,
construction/demolition landfills).
(Owners/operators of these units would
be required to comply with the
provisions of 40 CFR Part 257.)

As mentioned, owners/operators of
certain small landfills may be eligible
for exemption from the regulations
governing design, ground-water
monitoring, and corrective action.
See the section entitled "Exemptions
for Small Landfills," page 5.
                                                          When  Do the
                                                          Requirements Apply?

                                                                The requirements concerning
                                                                location restrictions, design criteria
                                                                (new and lateral expansion units
                                                          only), operating criteria, and closure/post-
                                                          closure care are effective October 9,1993.
                                                          Ground-water monitoring and corrective
                                                          action requirements are effective three,
                                                          four, or five years after October 9,1991,
                                                          depending on a unit's proximity to
                                                          drinking water intakes (see sidebar,
                                                          page 15). The financial assurance
                                                          requirements are effective April 9,1994.

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These dates reflect the requirements of
the federal MSWLF criteria. Contact
your state or tribal authority to deter-
mine specific state/tribal effective dates.
Implementation

of the Regulations:

Federal, State, Tribal,

and Owner/Operator

Responsibilities

Implementation by approved
states and Indian tribes
States and tribes are entitled to develop
their own permitting programs
incorporating the federal landfill criteria
to ensure that owners/operators are
complying. States and tribes also may
establish requirements that are more
stringent than those set by the federal
government.  EPA's role is to review
and approve these programs.

EPA is developing the State/Tribal
Implementation Rule, which will
delineate the requirements for receiving
EPA approval. For permit programs to
be considered adequate, a state or tribe
must have the capability of issuing
permits or some other form of prior
approval, and must establish conditions
requiring owners/operators to comply
with the landfill regulations. A state or
tribe must also be able to ensure
compliance through monitoring and
enforcement actions and must provide
for public participation.

By securing approval for its program, a
state or tribe has the opportunity for
more flexibility and discretion in
implementing the criteria according to
local needs and conditions. Owners/
operators located in a jurisdiction with
an approved program may benefit from
this potential flexibility, which extends
to all parts of the regulations (see box,
page 6).

Implementation in states/tribes
without approved programs
EPA expects that although most states
will be approved by the effective date of
the rule, some simply may not apply. In
these cases, owners/operators are
required to implement the federal
regulations. Each owner/operator must
document compliance and supply this
documentation to the state or tribe on
request. Owners/operators must
comply with state/tribal requirements.

Citizen roles
While state, tribal, and local
governments are responsible for
ensuring compliance with their waste
programs, private citizens play an
important role, too. Individuals can
help ensure that facilities comply with
state or tribal rules and regulations
through such activities as participating
in any public meetings regarding
landfill siting and permit issuance, and
working closely with their responsible
state, tribal, and local officials. Citizens
also have the right to sue landfill
owners/operators who are not in
compliance with the federal regulations.
Exemptions for Small
Landfills

       Approximately 6,000 municipal
       landfills are potentially subject
        to the criteria. Quite a few —
nearly 50 percent — are denned as
"small" landfills, meaning they receive
an average of no more than 20 tons of
municipal solid waste per day (figured
annually).  These landfills generally
serve communities of fewer than 10,000
people.

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The landfill design, ground-water
monitoring, and corrective action
provisions required under the criteria
are likely to be expensive. Small
communities might be unable to spread
these costs among many users, thereby
leading to significant increases in per-
capita disposal assessments.

The regulations are designed to provide
the opportunity for some relief from the
more costly requirements without
compromising human health or the
environment. An owner/operator of a
small landfill may be exempted from the
design, ground-water monitoring, and
corrective action requirements under
two circumstances:

   1) There is no evidence of ground-
     water contamination, the
     community has no practical waste
     management alternative, and the
    landfill is located in an area that
    receives less than 25 inches of
    precipitation annually.

  2) There is no evidence of ground-
    water contamination and the
    community undergoes an annual
    interruption of surface transporta-
    tion, lasting at least three
    consecutive months, that prevents
    access to a regional facility. This
    exemption is less widespread since,
    for example, it may be more
    applicable to certain communities
    in rural Alaska.

These exemptions are available to
qualifying small landfills in all  states or
tribal jurisdictions, even those without
EPA-approved permitting programs,
providing the state or tribal program
does not restrict the exemption.
Some small landfills
serving small
communities, such
as this one in the
dry, western United
States, may qualify
for exemption from
some of the
requirements.

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        Special
restrictions apply
 to landfills sited
  infloodplains,
 indicated here as
 the shaded area.
(The exemptions supplement the
flexibility in implementing the
regulations given all communities in
states and tribal jurisdictions with
approved programs. See page 6.)

Owners/operators qualifying for
exemptions must show why they
qualify and include the documenting
information in their operating records.
Owners/operators are also required to
comply with all other MSWLF
regulations, including the location,
operation, closure and post-closure, and
financial assurance provisions.

If the owner/operator of an exempt
facility learns of ground-water
contamination at the site, the exemption
is no longer applicable and the owner/
operator must comply with the
requirements for design, ground-water
monitoring, and corrective action.
Complying With
the Regulations
T
he regulations describe six
categories of criteria for
municipal solid waste landfills:
                                                             1) Location
                                                             2) Operation
                                                             3) Design
                                                             4) Ground-water monitoring and
                                                               corrective action
                                                             5) Closure and post-closure care
                                                             6) Financial assurance

                                                         Owners/operators are responsible for
                                                         reviewing the criteria to determine
                                                         which of the provisions apply to their
                                                         landfill(s). (Owners/operators should
                                                         refer to EPA's Technical Manual for Solid

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Waste Disposal Facility Criteria for
details.) They should also bear in mind
that state or tribal programs might
include provisions that do not mirror
the federal provisions discussed below.
Owners/operators are therefore
encouraged to work with their state and
tribal regulators in complying with the
regulations.

Location
There are six location restrictions that
apply to municipal landfills. Owners/
operators must demonstrate that their
units meet the criteria and keep the
demonstration documents in the facility
operating record.

If an owner/operator cannot show
compliance with the airport safety,
floodplain, or unstable-area provisions,
the unit must be closed by October 9,
1996. However, states and tribes with
EPA-approved programs can extend
this deadline by as much as two years
when no alternative waste management
capacity exists and there is no
immediate threat to human health and
the environment.
Restricted areas
include:

1. Airports
The owner/operator
of a municipal
landfill located
within 10,000 feet of
the end of any
airport runway used
by turbojet aircraft,
or within 5,000 feet of
any airport runway
used only by piston-
type aircraft, must
demonstrate that the
unit does not pose a
bird hazard.
Location Criteria Summary
Location Applicability*


Airport Safety N,E,L
Floodplains N,E,L
Wetlands N,L
Fault Areas N,L
Seismic Impact N,L
Zones
Unstable Areas N,E,L
*(N=New, E=Existing, L=Lateral Expansion)
Closure
If Demonstration
Cannot Be Met?
Yes
Yes
No
No
No
Yes

If an owner/operator plans to build a
new unit or laterally expand an existing
unit within 5 miles of any airport, the
airport and the Federal Aviation
Administration must be notified.

2. Floodplains
Units located in 100-year floodplains
cannot restrict the flow of the 100-year
flood, reduce the temporary water
storage capacity of the floodplain, or
allow the washout of solid waste.
The regulations
impose special
requirements on
landfills near airports
to prevent
compromises to air
traffic safety.

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 10
 Landfills may not
be built in unstable
    areas prone to
  landslides, mud-
slides, or sinkholes,
   such as the one
      shown here.
3. Wetlands
In general, owners/operators of new or
expanding municipal landfills may not
build or expand in wetlands. However,
states or tribes with EPA-approved
permitting programs can make
exceptions for units able to show:
   • No siting alternative is available.
   • Construction and operation will
    not (1) violate applicable state/
    tribal regulations on water quality
    or toxic effluent; (2) jeopardize any
    endangered or threatened species
    or critical habitats; or (3) violate
    protection of a marine sanctuary.
   • The unit will not cause or
    contribute to significant
    degradation of wetlands.
   • Steps have been taken to achieve no
    net loss of wetlands by avoiding
    effects where possible, minimizing
    unavoidable impacts, or making
     proper compensation (e.g.,
     restoring damaged wetlands or
     creating man-made wetlands).

4. Fault areas
New units or lateral expansions are
generally prohibited within 200 feet of
fault areas that have shifted since the
last Ice Age. However, the director of an
approved state or tribal program may
allow an alternative setback distance of
less than 200 feet if the owner/operator
can show that the unit will maintain
structural integrity in the event of a fault
displacement.

5. Seismic impact zones
When a new or laterally expanding unit
is located in a seismic impact zone, its
containment structures (liners, leachate
collection systems, surface-water control
systems) must be designed to resist the
effects of ground motion due to
earthquakes.

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                                                                                               11
6. Unstable areas
All owners/operators must show that
the structure of their units will not be
compromised during "destabilizing
events," including:

   • Debris flows resulting from heavy
    rainfall.
   • Fast-forming sinkholes caused by
    excessive ground-water
    withdrawal.
   • Rockfalls set off by explosives or
    sonic booms.
   • The sudden liquification of the soil
    after a long period of repeated
    wetting and drying.


Operation
All owners/operators must comply
with the requirements for proper
management of municipal solid waste
landfills. These cover a range of
procedures, including:

1. Receipt of regulated hazardous waste
The owner/operator must set up a
program to detect and prevent disposal
of regulated quantities of hazardous
wastes and polychlorinated biphenyl
(PCB) wastes. The program must
include procedures for random
inspections, record keeping, training of
personnel to recognize hazardous and
PCB wastes, and notification of the
appropriate authorities if such waste is
discovered at the facility.

2. Cover material
The owner/operator must cover
disposed solid waste with at least 6
inches of earthen material at the end of
each operating day to control vectors,
fires, odors, blowing litter, and
scavenging. An approved state or tribe
may allow an owner/operator to use an
alternative cover material or depth,
and/or grant a temporary waiver of the
cover requirement (if local climate
conditions make such a requirement
impractical).

3. Vectors
The owner/operator is responsible for
controlling vector populations.  Vectors
include any rodents, flies, mosquitoes,
or other animals or insects capable of
transmitting disease to humans.
Application of cover at the end of each
operating day generally controls vectors.

4. Explosive gases
The owner/operator must set up a
program to check for methane gas
emissions at least every three months. If
the limits specified in the regulations are
exceeded, the owner/operator must
immediately notify the state/tribal
director (that is, the official in the state or
area responsible for implementing the
landfill criteria) and take immediate
steps to protect human health and the
environment. The owner/operator also
must develop and implement a
remediation plan within 60 days. States
and tribal jurisdictions with approved
programs may alter this interval.

5. Air quality
Open burning of waste is not permitted
except for infrequent burning of
agricultural waste, silvicultural waste,
land-clearing debris, diseased trees, or
debris from emergency clean-up
operations. Owners/operators must
comply with the applicable
requirements of their State
Implementation Plans for meeting
federal air quality standards.

6. Access
The owner/operator must control
public access to prevent illegal
dumping, unauthorized vehicular
traffic, and public exposure. Artificial
and/or natural barriers may be used to
control access.

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    Owners and
  operaters must
 ensure that each
   day's waste is
covered to control
litter and disease-
 bearing vermin.
7. Storm water run-on/run-off
The owner/operator must build and
maintain a control system designed to
prevent storm waters from running on
to the active part of the landfill. The
run-on control system must be able to
handle water flows as heavy as those
expected from the worst storm the area
might undergo in 25 years.

The owner/operator also must build
and maintain a surface water run-off
control system that can collect and
control, at a minimum, the surface water
volume that results from a 24-hour, 25-
year storm. Run-off waters must be
managed according to the requirements
of the Clean Water Act, particularly with
regard to the restrictions on the
discharge of pollutants into water
bodies and wetlands.

8. Surface water protection
All landfills must be operated in a  way
that ensures they do not release
pollutants that violate the Clean Water
Act, which protects surface waters.
9. Liquids
A landfill cannot accept bulk or
noncontainerized liquid waste unless (1)
the waste is nonseptic household waste,
or (2) it is leachate or gas condensate
that is recirculated to the landfill, and
the unit is equipped with a composite
liner and leachate collection system as
described below under "Design."

Containers of liquid waste may be
placed in the landfill only if the
containers: (1) are similar in size to those
typically found in household waste,
such as cleaning, automotive, or home-
improvement products (i.e., containers
such as 55-gallon drums are excluded);
(2) are designed to hold liquids for use
other than storage; or (3) hold only
household waste (containers collected in
routine pickups from households).

10. Record-keeping
Owners/operators are required to keep
certain documents in or near the facility,
including:

   • Location restriction
     demonstrations.
   • Procedures for  excluding
     hazardous waste.
   • Gas monitoring results.
   • Leachate or gas condensate system
     design documentation.

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                                                                                                 13
   • Ground-water monitoring and
     corrective action data and
     demonstrations.
   • Closure and post-closure plans.
   • Cost estimates and financial
     assurance documentation.


 Design
 The criteria for landfill design apply
 only to new units and lateral
 expansions. (Existing units are not
 required to retrofit liner systems.) The
 criteria give owners/operators two basic
 design options.

 First, in states and tribal areas with EPA-
 approved programs, owners/operators
 may build their landfills to comply with
 a design approved by the state/tribal
 director. In approving the design, the
 director must ensure that it meets the
 EPA performance standard, i.e., that
 Maximum Contaminant Levels (MCLs)
 will not be exceeded in the uppermost
 aquifer at a "relevant point of
 compliance." This point is determined
 by the approved-state/tribal director,
 but it must be no farther than 150 meters
 from the landfill unit boundary and on
 land owned by the landfill owner. (EPA
 has already set MCLs for a number of
 solid waste constituents; see table.)

 In reviewing these performance-based
 designs, approved states and tribes also
 must consider other factors, such as the
 hydrogeologic characteristics of the
 facility and surrounding land, the local
 climate, and the amount and nature of
 the leachate.

 The second option is a design developed
 by EPA that consists of a composite liner
 and a leachate collection system.  In
 general, landfills in states or tribal
jurisdictions without EPA-approved
 programs must use this design. The
 composite liner system combines an
 upper liner of a synthetic flexible
  Maximum Contaminant Levels
          (as of October 9,1991)

  Chemical	MCL (mg/1)

  Arsenic                      0.05
  Barium                      1.0
  Benzene                      0.005
  Cadmium                    0.01
  Carbon tetrachloride             0.005
  Chromium (hexavalent)          0.05
  2,4-Dichlorophenoxy acetic acid    0.1
  1,4-Dichlorobenzene             0.075
  1,2-Dichloroethane              0.005
  1,1-Dichloroethylene             0.007
  Endrin                       0.0002
  Fluoride                      4
  Lindane                      0.004
  Lead                         0.05
  Mercury                      0.002
  Methoxychlor                  0.1
  Nitrate                      10
  Selenium                     0.01
  Silver                        0.05
  Toxaphene                    0.005  „
  1,1/1-Trichloromethane           0.2
  Trichloroethylene               0.005
  2,4,5-Trichlorophenoxy acetic acid  0.01
  Vinyl chloride                  0.002
membrane and a lower layer of soil at
least 2 feet thick with a hydraulic
conductivity of no greater than 1 X 10~7
cm/sec. The leachate collection  system
must be designed to keep the depth of
the leachate over the liner to less than 30
centimeters.

The criteria also provide an option for
owners/operators in nonapproved
states or tribal jurisdictions to use the
performance standard (rather than the
EPA design described above), providing
that both of the following conditions are
met:

   • EPA does not promulgate a State/
    Tribal Implementation Rule by
    October 9,1993.

   • The state or tribe determines that
    the alternative design meets the

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14
  Performance of a
 landfill cover must
meet certain federal
 minimum criteria.
    performance standard in the
    federal criteria; the state or tribe
    petitions EPA to review this deter-
    mination; and EPA does not deny
    the determination within 30 days.

Ground-Water Monitoring
and Corrective Action
This section sets criteria for ground-
water monitoring systems, programs for
sampling and analysis of ground water,
and corrective action as necessary to
ensure that human health and the
environment are protected. Here, as
with the other provisions in the federal
criteria, approved states and tribes may
adopt programs with requirements that
are more stringent than the federal
criteria. Again, owners/operators are
encouraged to work closely with their
states or tribes.

Ground-water monitoring systems
Generally, ground-water monitoring
must be conducted at all MSWLF units.
Owners/operators must install enough
ground-water monitoring wells in the
appropriate places to accurately assess
the quality of the uppermost aquifer (1)
beneath the landfill before it has passed
the landfill boundary (to determine
background quality) and (2) at a
relevant point of compliance (down-
gradient). Owners/operators should
consider the specific characteristics of
the sites when establishing their
monitoring systems, but the systems
must be certified as adequate by a
qualified ground-water scientist or the
director of an EPA-approved state/
tribal program.

In approved states and tribal jurisdic-
tions, an owner/operator may be able to
obtain a variance from the ground-water
monitoring requirements if the owner/
operator can demonstrate that the
landfill is located over a geologic
structure that will prevent hazardous
constituent migration to the ground
water. The demonstration must show
that no migration of constituents from
the unit will occur during the unit's life,
including the closure and post-closure
care period.

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                                                                                            15
Detection and assessment monitoring
programs
States and tribes with EPA-approved
programs have the flexibility to design
ground-water monitoring programs that
are well-suited to the landfills operating
in their area, and that may therefore
differ from the federal program. In
states/tribes without an approved
permit program, owners/operators
must follow the federal regulations
describing detection and assessment
monitoring.

During detection monitoring, owners/
operators must take ground-water
samples and analyze them for specific
constituents (as defined in the federal
regulations or by the director of an
approved state/tribal program). Under
the federal regulations, sampling and
analysis must be conducted at least
twice a year. Approved state/tribal
programs may set alternative
frequencies, but sampling and analysis
must be done at least annually.  If
significant ground-water contamination
is detected, owners/operators may seek
to demonstrate that the results are due
to contamination from other sources,
sampling error, or natural variation in
ground-water quality. Otherwise,
owners/operators must notify the
appropriate state/tribal official and
begin assessment monitoring.

The purpose of assessment monitoring
is to determine the nature and extent of
ground-water contamination. During
assessment monitoring, ground-water
must be analyzed both for constituents
detected initially and for other
constituents (defined in the federal
criteria or by the director of an approved
state/tribal program). States and tribes
with EPA-approved programs specify
the frequency for sampling and analysis
conducted during assessment
monitoring. In nonapproved states and
tribes, the frequency is specified in the
          Schedule for Implementing
           Ground-Water Monitoring

    An EPA-approved state or tribe can set its own
    schedule, provided at least 50 percent of all the state's or
    tribe's units comply by October 9,1994, and all are in
    compliance by October 9,1996.
    If a state or tribe has not been approved by EPA,
    owners/operators must comply with the following
    schedule for installing ground-water monitoring
    systems:
       • If a site is less than 1 mile in any direction from a
        drinking water intake (whether surface or ground-
        water), by October 9,1994.
       • If the site is farther than 1 mile but less than 2
        miles, by October 9,1995.
       • If the site is more than 2 miles, by October 9,1996.
    New units must install monitoring systems prior to
    accepting any waste.
 federal regulations. As in detection
 monitoring, if ground-water analysis
 shows significant contamination,
 owners/operators might be able to
 make the determination that the landfill
 is not the source of the contamination. If
 the owner/operator cannot make this
 determination, then the ground water
 must be cleaned up (see "Corrective
 Action" below). In EPA-approved states
 and tribes, it must be cleaned up to
 levels specified by the state/tribal
 director; in nonapproved states and
 tribes, contamination must not exceed
 federal limits set for drinking water
 quality or background levels.

 The federal ground-water monitoring
 requirements are more complex and
 technical than described here. A
 thorough explanation of the regulations
 can be found in EPA's Technical Manual
for Solid Waste Disposal Facility Criteria.

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    16
 Some owners/operators
   may choose to install
     leachate collection
systems, such as the one
     shown here. These
 systems are designed to
  collect any fluids that
 seep down through  the
 landfill.  The fluids can
     be recycled in  the
   landfill or treated for
     disposal elsewhere.
Ground-water monitoring regulations in
states and tribes with EPA-approved
programs may differ somewhat from
the federal regulations. Landfill
owners/operators conducting ground-
water monitoring in nonapproved states
and tribes must comply with the federal
regulations in addition to their state's or
tribe's regulations. In all cases, the
owner/operator is encouraged to work
with his or her state or tribe to ensure
compliance with all applicable
regulations.

The corrective action program
Cleaning up ground water requires
corrective action. The owner/operator
must assess corrective measures and
select the appropriate one(s). During
corrective action, the owner/operator
must continue ground-water
monitoring in accordance with the
assessment monitoring program.

While evaluating potential remedies, the
owner/operator must hold a public
meeting to discuss them. Once the
remedy has been selected, the owner/
operator is responsible for carrying it
out.  During this period, a ground-water
monitoring program must be
established to measure the effectiveness
of the remedy. The owner/operator
must continue corrective action until
compliance with the clean-up standard
has been met for three consecutive
years, although the director of an
approved state or tribal program may
specify a different period.

Closure and Post-Closure
Care
The criteria establish specific standards
for all owners/operators to follow when
closing a landfill and setting up a
program of monitoring and
maintenance during the post-closure
period.  The owner/operator must enter
the closure and post-closure plans into
the landfill's operating records by
October 9,1993, or by the initial receipt
of waste, whichever is later.

Owners/operators of landfills that stop
receiving waste between October 9,
1991, and October 9,1993, must install
final covers that meet the federal criteria
within six months of the last receipt of
waste. Here again, owners/operators
should work with their state or tribal
program officials to ensure that all
applicable closure requirements are
considered.
                                1111

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                                                                                              17
The final cover must be designed and
constructed to have a permeability less
than or equal to the bottom liner system
or natural subsoils, or a permeability no
greater than IxlO"5 cm/sec, whichever is
lower. Thus, the regulation is in the
form of a performance standard that
must be achieved by the owner/
operator.

The final cover must be constructed of
an infiltration layer composed of a
minimum of 18 inches of earthen
material to minimize the flow of water
into the closed landfill. The cover must
also contain an erosion layer to prevent
the disintegration of the cover. The
erosion layer must be composed of a
minimum of 6 inches of earthen material
capable of sustaining plant growth.

When a landfill's bottom liner system
includes a flexible membrane or
synthetic liner, the addition of a flexible
liner in the infiltration layer cover will
generally be the only design that will
allow the final cover design to achieve a
permeability less than or equal to the
bottom liner.

The director of an approved state or
tribe may approve an alternative final
cover design that achieves an
equivalent reduction in infiltration
and protection from erosion as the
design described above.

For 30 years after closure, the owner/
operator is responsible for maintaining
the integrity of the final cover, monitor-
ing ground water and methane gas, and
continuing leachate management.
(Approved states/tribes may vary this
interval.)

Financial Assurance
All units except those owned or
operated by state or federal govern-
ment entities must comply with the
financial assurance criteria, which are
         Closing a Landfill — and Beyond
       Owners/operators must follow certain
    procedures when closing a municipal landfill,
    including the following:

      • The state or tribe must be notified prior to closure.
      • A closure plan must be prepared.
      • The final cover must consist of at least 18 inches of
        earthen material of a specified permeability, with
        an erosion layer at least 6 inches thick. (An
        approved state/ tribe may allow an alternative
        cover design.)
      • An independent certified engineer must certify that
        closure was conducted in accordance with the
        plan.
      • The deed of property must note that the property
        was used as a landfill and that future use is
        restricted.
       For 30 years following closure (or an alternative
    period designated by an approved state or tribe),
    owners/operators are responsible for maintaining the
    integrity of the final cover, continuing to monitor
    ground water and methane, and continuing leachate
    management.
effective April 9,1994.

The owner/operator must demonstrate
financial responsibility for the costs of
closure, post-closure care, and corrective
action for known releases. This require-
ment can be satisfied by the following
mechanisms:

   • Trust fund with a pay-in period.
   • Surety bond.
   • Letter of credit.
   • Insurance.
   • Guarantee.
   • State assumption of responsibility.
   • Multiple mechanisms (a combina-
    tion of those listed above).

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18
                   Owners/operators of landfills in
                   approved states or tribal jurisdictions
                   may also use other state-approved
                   mechanisms.

                   EPA is currently developing provisions
                   for four additional financial mechanisms
                   that owners/operators can use to satisfy
                   the financial assurance requirements: (1)
                   a financial test for local government
                   owners/operators; (2) a financial test for
                   corporate owners/operators; (3) a
                   guarantee for local governments that
                   wish to cover the costs of a municipal
                   landfill for an owner/operator; and (4) a
                   guarantee for corporations that wish to
                                        cover the costs of
                                        a landfill for an
                                        owner/operator.
Conclusion
       The standards described in this
       booklet are federal minimum
       requirements for owners/
operators of MSWLF units. Readers
should understand that the regulation of
municipal landfills is, and will continue
to be, primarily a state and tribal
function. States and tribes are therefore
urged to revise their programs as soon
as possible to incorporate these criteria,
so that they can take advantage of the
flexibility that accompanies program
approval.

Owners/operators are again reminded
that state and tribal programs may be
more stringent than the federal criteria.
They should work closely with state or
tribal program officials and their
regional EPA office to address questions
about the requirements.

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  Areas of Flexibility for EPA-Approved States and Tribes
                                i
States and tribes with approved permitting programs have the opportunity to provide owners/
operators additional flexibility. Some examples of this flexibility are listed below.

Approved states or tribes may:
Location:
   • Allow siting of new and laterally
    expanding landfills in wetlands, providing
    certain conditions are met.
   • Extend deadlines for closure of existing
    landfills that do not comply with the
    unstable area, floodplain, and airport safety
    provisions.

Operation:
   • Allow use of alternative cover materials.
   • Grant temporary waivers of cover
    requirement.
Design:
   • Approve landfill designs appropriate for
    site-specific conditions.
   • Approve an alternative frequency for
    detection monitoring.
   • Modify list of assessment monitoring
    parameters (Appendix n constituents).
   • Specify alternative frequencies for    ,
    assessment monitoring.
   • Establish Ground-water Protection
    Standards for any constituent for which a
    Maximum Contaminant Level has not been
    established.
Corrective action:
   • Determine that cleanup of a particular
    Appendix n constituent is not necessary.
   • Specify an alternative time period defining
    the end of corrective action.
Ground-water monitoring:
   • Establish alternative schedules for existing
    landfills and lateral expansions of existing
    landfills to comply with ground-water
    monitoring.
   • Establish a site-appropriate boundary (or
    relevant point of compliance) for ground-
    water monitoring (and corrective action
    and design).
   • Allow use of a multi-unit ground-water
    monitoring system, instead of separate
    monitoring systems for each unit at a
    facility.
   • Modify list of detection monitoring
    parameters (Appendix I constituents).
Closure and post-closure care:
   • Approve use of an alternative final cover.
   • Grant extensions beyond specified
    deadline for beginning closure activities.
   • Grant extensions beyond specified
    deadline for completing closure.
   • Reduce or increase the 30-year post-closure
    care period.
Financial assurance:
   • Approve use of alternative financial
    assurance mechanisms.

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                                                                                             19
For More Information
      For more information about specific requirements for solid waste landfills in
      your area, contact your state solid waste agency. If you don't know how to
      reach them, call one of the resources listed below. The RCRA Hotline
maintains current lists of all state solid and hazardous waste management officials.
While these information centers are the best place to start collecting information, it
may still be useful to ask these contacts if some other source may be able to give you
additional help.

RCRA Hotline
Provides information about RCRA regulations and policies, and takes document requests.

           Hours: Monday-Friday, 8:30 a.m. to 7:30 p.m., EST
        Telephone: Toll-free — (800) 424-9346
                  TDD (hearing impaired) — (800) 553-7672
                  Washington metro area — (703) 412-9810
                  TDD —(703)412-3323


EPA RCRA Information Center (Docket)
Maintains and tracks policy and guidance documents; provides nontechnical assistance and
written reference services; develops and disseminates public information materials.

           Hours: Monday-Friday, 9:00 a.m. to 4:00 p.m., EST
        Telephone: (202) 260-9327
         Address: RCRA Information Center
                  U.S. Environmental Protection Agency
                  401 M Street, SW. (OS-305)
                  Washington, DC 20460


Solid Waste Assistance Program
Collects and distributes information on all aspects of municipal solid waste management.

           Hours: Monday-Friday, 8:30 a.m. to 5:00 p.m., EST
        Telephone: Toll-free — (800) 677-9424
         Address: Solid Waste Assistance Program
                  P.O. Box 7219
                  Silver Spring, MD 20910


National Response Center
Accepts reports of oil and chemical spills or any other environmental incident.

           Hours: 24 hours a day, 365 days a year.
        Telephone: Toll-free — (800) 424-2675
                  Washington metro area — (202) 426-2675


EPA Small Business Ombudsman
Helps small businesses comply with environmental laws and EPA regulations.

           Hours: Monday-Friday, 8:30 a.m. to 5:00 p.m., EST
        Telephone: Toll-free — (800) 368-5888
                  Washington metro area — (703) 305-5938

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 20
EPA Regional Contacts
    U.S. EPA Region 1
    Waste Management
     Division (HEE-CAN 6)
    JFK Federal Building
    Boston, MA 02203
    (617) 573-9656

    U.S. EPA Region 2
    Air & Waste Management
     Division (2AWM-SW)
    26 Federal Plaza
    New York, NY 10278
    (212) 264-0002

    U.S. EPA Region 3
    RCRA Solid Waste
     Program (3HW53)
    841 Chestnut Street
    Philadelphia, PA 19107
    (215) 597-7936
U.S. EPA Region 4
Waste Management
  Division
  (4WD-RCRA-FF)
345 Courtland Street, NE
Atlanta, GA 30365
(404) 347-2091

U.S. EPA Region 5
Waste Management
  Division (H-7J)
77 West Jackson Blvd.
Chicago, IL 60604
(312) 353-4686

U.S. EPA Region 6
RCRA Programs Branch
First Interstate Bank
  Tower
1445 Ross Avenue,
  Suite 1200
Dallas, TX  75202
(214) 655-6655
U.S. EPA Region 7
Waste Management
  Division
726 Minnesota Avenue
Kansas City, KS  66101
(913) 551-7666

U.S. EPA Region 8
Hazardous Waste
  Management Branch
  (HWM-WM)
999 18th Street, Suite 500
Denver, CO 80202-2466
(303) 293-1661

EPA Region 9
Hazardous Waste
  Management
  Division (H-3-1)
75 Hawthorne Street
San Francisco, CA 94105
(415) 744-2074
U.S. EPA Region 10
Hazardous Waste Division
  (HW-114)
1200 Sixth Avenue
Seattle, WA 98101
(206) 553-2857
                                                             U.S. GOVERNMENT PRINTING OFFICE: 1993 719-116/61149

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The information in this document has been
funded wholly or in part by the United
States Environmental Protection Agency
(EPA) under assistance  agreement
#X820495-01-0  to  the  Solid  Waste
Association of North America. Ithasbeen
subjected to the  Agency's peer and
administrative  review and has been
approved for publication  as an EPA
document.  Mention of trade names or
commercial products does not constitute
endorsement or recommendation for use.

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