United States
Environmental Protection
Agency
Solid Waste and
Emergency Response
(5305W)
EPA530-R-96-020
November 1996
v>EPA Preparing No-Migration
Petitions for Municipal
Solid Waste Disposal
Facilities
Guidance Document
RAFT
Reproduced on Paper that Contains at least 20% Post Consumer Fiber
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Preparing No-Migration Petitions
for Municipal Solid Waste Disposal Facilities
Guidance Document
DRAFT
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DISCLAIMER
The information in this" document has been funded wholly or in part by the United States Environmental
Protection Agency (EPA) under Contract Number 68-W5-OQ57. Mention of trade names or commercial
products does not constitute endorsement or recommendation for use.
NOTICE
The policies set forth in this manual are not final EPA action, but are intended solely as guidance. They
are not intended, nor can they be relied upon, to create any rights enforceable by any party in litigation
with the United States. EPA officials may decide to follow the guidance provided in this manual, or to act
at variance with the guidance, after analysis of specific site circumstances. EPA also reserves the right to
change this guidance at any time without public notice.
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CONTENTS
Section
1.0 INTRODUCTION
Page
2.0 STEP 1: MAKE AN EARLY DETERMINATION OF ELIGIBILITY ................... 3
2.1 Recent Changes in Federal Regulations Governing Small, Dry, Remote MS WLFs ..... 3
2.2 Determination of an MSWLF's Eligibility for a A No-Migration Exemption ......... 4
2.2.1 Key Screening Criteria ........ . ................................... 4
2.2.2 Analysis Against Key Screening Criteria for MSWLFs That Have Received
Exemptions ... ......................................... . ........ 5
2.2.3 Estimation of Time of Travel ........ ---- . ......................... 12
2.3 Content of an NMP [[[ 15
3.0 STEP 2: ESTIMATE AND ANALYZE THE COST OF THE NMP ... .................. 21
3.1 Estimate the Cost of an NMP ......... . ................................... 21
3.2 Analyze the Cost of the NMP ............................................. 24
4.0 STEP 3: FOLLOW COST-EFFECTIVE METHODS OF PREPARING THE NMP ........ 26
4.1 Prepare a Clear Written Description of Needs ................................ 26
4.2 Discuss Needs With Consulting Firms ..................... ................. 26
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1.0 INTRODUCTION
This technical guidance has been developed to assist owners and operators of municipal solid waste
landfills (MSWLF) in evaluating and preparing information for a No-Migration Petition (NMP) under the
exemptions from requirements for groundwater monitoring stated in 40.Code of Federal Regulations
(CFR) 258.50(b). The regulation states:
"Groundwater monitoring requirements under 40 CFR 258.51 through 40 CFR 258.55 of this part
may be suspended by the Director of an Approved State/Tribe for a MSWLF unit if the operator
can demonstrate that there is no potential for migration of hazardous constituents from that
MSWLF unit to the uppermost aquifer (as defined in 40 CFR 258.2) during the active life of the
unit and the post-closure care period. This demonstration must be certified by a qualified
groundwater scientist and approved by the director of an approved State/Tribe, and must be based
upon:
(1) Site-specific field collected measurements, sampling, and analysis of physical,
chemical, and biological processes affecting contaminant fate and transport, and
(2) Contaminant fate and transport predictions that maximize contaminant migration
and consider impacts on human health and the environment."
The federal regulations quoted above are performance standards that each state is to include, in its
permitting standards. Individual states are not required to allow exemptions based on no-migration
petitions (NMP). However, most states will consider such petitions. Because the federal regulations are
performance standards, they allow states considerable flexibility in the choice of the criteria and methods
used to evaluate no-migration petitions. Therefore, the criteria that guide decisions about NMPs differ
from state to state, as do requirements governing the amount and level of detail in data required for an
NMP. Differences also occur among petitions submitted in a single state, because less information is
required for a site that has a relatively simple hydrogeologic setting than is required for sites in more
complex settings. Many site-specific factors will influence the amount of information required to support a
decision about an NMP, including predicted time of travel for hazardous constituents and other conditions.
Because of such differences in the types and amounts of data required in an NMP, it is not possible to
predict the cost of preparing one tor a given site or the ultimate outcome of the process without collecting
preliminary information. The NMP process offers no guarantee that the state or tribal director will
approve an exemption from requirements for groundwater monitoring. However, the owner or operator
of a MSWLF can use this manual to pursue an exemption from requirements for groundwater monitoring
in a manner that will minimize the time and expense of either preparing an NMP or deciding to abandon
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the effort. This guidance presents a step-by-step information collection process that is integrated with a
number of crucial milestones. At any of those milestones, the preparer can decide whether to continue or
to abandon the effort without spending more time and money. These crucial decision (mints help minimize
the chance of abandoning a valid NMP. This manual also focuses on the staged collection of data, from
cheapest to most expensive, for those key variables that provide the strongest basis for predictions of time
of travel for'hazardous constituents in the unsaturated zone.
The three-step process presented in this guidance allows evaluation of the chances of success and supports
decisions about whether to continue or to abandon the NMP process, as information is collected. The
three steps are presented in Chapters 2.0 through 4.0 of this document, which are summarized below.
Chapter 2.0: Step 1 - Make an Early Determination of Eligibility: 'Step 1 is a
screening step that has three main parts. First, the recent reinstatement of the exemption
for small, dry, remote MSWLFs is explained. For MSWLFs that are not eligible for that
exemption, collection of preliminary data to assess the potential for a no-migration
exemption is discussed. Finally, the discussion describes the role of the state or tribal
authorities in the NMP process and offers some practical advice about learning about
policies, requirements, and information resources.
Chapter 3.0: Step 2 - Estimate the Cost of an NMP: Completion of Step 2 will help
build a simple estimate of the .cost of preparing an NMP. The estimate will include the
cost of obtaining regional and site-specific information necessary for the petition process.
The estimate also will consider the costs of preparing the necessary report, including
analytical and report preparation support from a consultant.
Chapter 4.0: Step 3 - Collect and Analyze Information and Data and Write the
Petition: Step 3 is a guide to selecting and working with a consulting firm to plan for the
collection and evaluation of data and to preparing the NMP.
The approach set forth in this guidance should enable the owner or operator of a MSWLF to prepare a
petition at the least possible expenditure of time and money. The approach relies on early warning signs
that can lead to early abandonment of the effort.
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2.0 STEP1: MAKE AN EARLY DETERMINATION OF ELIGIBILITY
This chapter has three sections. Section 2.1 presents information about the recent reinstatement of the
exemption from requirements for groundwater monitoring available to MSWLFs in dry and remote areas.
Section 2.2 introduces key hydrogeologic parameters used in collecting preliminary data to assess the
potential that a site is eligible for a no-migration demonstration. Section 2.3 then discusses the role of state
or tribal authorities in the NMP process. The discussion includes some practical advice for learning about
policies, requirements, and information resources.
2.1 Recent Changes in Federal Regulations Governing Small, Dry, Remote MSWLFs
The Land Disposal Program Flexibility Act of 1996, enacted in March 1996, reinstated some federal.
regulations that previously had been vacated by .a court decision. The rule changes were promulgated on
September 25, 1996 (61 FR 50410). Those regulations provide an exemption from requirements for
groundwater monitoring for MSWLFs that are "small" and "dry" or "small" and "remote." There are an
estimated 800 such MSWLFs in the United States.
The U.S. Environmental Protection Agency's (EPA) definition of a "small" MSWLF states that such a
facility must receive an annual average of 20 or fewer tons of waste per day. A "dry" MSWLF, by
definition, must be located in an area that annually receives 25 or fewer inches of percipitation. All such
MSWLFs are in the western United States.
EPA's definition of a "remote" MSWLF is one that serves a community that each year experiences an
interruption of surface transportation of at least three consecutive months' duration. In addition, the
MSWLF must exhibit no evidence of contamination of groundwater at the site and must serve a community
that has "no practicable alternative" to landfilling of its municipal solid waste. Almost all such facilities are
in the state of Alaska.
The exemptions described above are valid only under federal regulations; no state is required to allow
similar exemptions. A state can establish additional requirements for obtanining an exemption, if that
particular state will grant such an exemption at all. It is likely, however, that a state will base its decisions
about exemptions on criteria that closely resemble those applied under federal regulations. Owners and
operators of MSWLFs must work with state authorities to determine whether a particular facility is eligible
for exemption.
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2.2 Determination of an MSWLF's Eligibility for a A No-Migration Exemption
This section first describes key screening criteria that can be used in determining whether an MSWLF is a
candidate for a no-migration exemption. It then explains how to compare some key characteristics of a
facility with those of a number of other facilities that have received exemptions. Such a comparison can
help the owner or operator to determine the probability that an NMP will be successful. The section then
describes how to to calculate a conservative estimate of time of travel tor hazardous constituents from the
facility to the uppermost aquifer.
2.2.1
Key Screening Criteria
The five variables that significantly influence the time of travel of leachate from a MSWLF to the
uppermost aquifer are the depth to groundwater, the permeability of the soil, the precipitation rate, the
evapotranspiration potential, and the net infiltration rate. Therefore, these variables can be used at a
particular MSWLF as key screening criteria for determining the eligibility of a MSWLF for a no-migration
exemption. In the following paragraphs, each of the five variables is described.
The depth to groundwater is the distance from the bottom of the MSWLF to the first layer of saturated
soils that are capable of yielding water continually. Some state regulations define this saturated layer
differently, depending on the quality of the groundwater and the quantity of groundwater yield.
The permeability of the soil refers to the rate at which water travels through it under saturated flow
conditions. Permeability generally is measured in centimeters per second (cm/sec), but also can be
measured in feet per year, with one foot per year roughly equivalent to 1 x 10"* cm/sec.
The precipitation rate is the amount of rain received at a MSWLF over a given time period. It is usually
expressed as inches per year, but is generally averaged over a large number of years to account of annual
variability.
The evapotranspiration potential is the maximum amount of water that could be lost from the soil by the
actions of direct evaporation and transpiration through the leaves of vegetation in a given area. Its
estimation is based on such variables as average annual temperatures and humidities.
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The net infiltration rate is the percentage of precipitation that enters the soils in a given area. The rate
represents the portion of rain water that does not run out of the area and is not evaporated or transpired.
At MSWLFs in areas that generally have significant infiltration, leachate will move toward the
groundwater. At MSWLFs in areas in which there is little or no infiltration, movement of leachate toward
the groundwater will not occur.
2.2.2
Analysis Against Key Screening Criteria for MSWLFs That Have Received
Exemptions
Presented below are the results of an informal analysis of 32 NMPs filed by owners of MSWLFs who
were successful in securing no-migration exemptions from requirements for groundwater monitoring at
their facilities. Information about the 32 NMPs analyzed was obtained from the files of seven states:
Arizona, Idaho, Montana, Nevada, New Mexico, Utah, and Wyoming. In Wyoming, there were 18
successful NMPs; in Montana, 6; in Idaho, 3; in Utah, 2 and in Arizona, Nevada, and New Mexico, 1
each.
Table 2-1 summarizes the results of the informal analysis of successful NMPs. (Appendix A provides a
summary of criteria used by states to make determinations about such petitions and site-specific data, as
well as a comparison of parameters and values that were used in the analysis.) Through review of the
table, it is possible to make the following general observations about the characteristics of the 32 MSWLFS
for which NMPs were analyzed:
Large MSWLFs (those that receive more than 20 tons per day) and small MSWLFs (those
that receive less than 20 tons per day) submitted 53 and 47 percent of the NMPs,
respectively (19 MSWLFs submitted data on waste acceptance rates).
The values for the, criteria set forth in Table 2-1 do not appear to differ significantly
between large and small MSWLFs.
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I
TABLE 2-1: SUMMARY OF RESULTS OF AN INFORMAL ANALYSIS
OF 32 SUCCESSFUL NMPte IN SEVEN STATES1
el of2)
SEEOFMSWLF
(Tompacky)
>20
13
0.00
IDNMUTWY
ARIDMTNVUTWY
AVERAGE ANNUAL PRECIPITATION
(bcbd)
6-10
10.1 is
<25
0.00
11
NV
AR1OMTNMUTWY
ID MTWY
WY
MINIMUM DEPTH TO GROUNDWATER (Feel)
<50>
Sl-ltf
101 -ZOO1
201-300
301-400
0.00
0.00
ARMTUTWY
MTWY
WY
IDMTWY
ID MT UT
ID NM NV WY
MAXIMUM SOIL PERMEABUJTY (Beetffeu)
<0.01
0.01-0.1
0.11-1.0
i - 10.0 .
10.1 - ioo*
101 -1000*
>IOOO»
Nl
o.oo
0.00
0.00
0.00
'0.00
IDWY
UTWY
MTWY
UTWY
IDMTNMWY
IDNVWY
ARWY
MTWY
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TABLE 2-1: SUMMARY OF RESULTS OF AN INFORMAL ANALYSIS OF 32 SUCCESSFUL NMPs IN SEVEN STATES
(Page 2 of 2)
'1 ' y -^'a^Y^-i
HYDROGEOLOGIC MODELS
AVERAGE ANNUAL
EVAPOTRANS-
PIRATIONRATE
(Inches)
NMP COSTS
(x $1,000)
I V-'^, *
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Annual precipitation is less than 15 inches at more than 87 percent of the MSWLFs and
less than 25 inches at all the MSWLFs. Therefore, all the MSWLFs analyzed appear to be
dry (23 NMPs included data on annual precipitation).
Depths to groundwater exceeded 50 feet at more than 78 percent and 200 feet at more than
40 percent of the MSWLFs analyzed.
Maximum soil permeabilities (or hydraulic conductivities) were equal to or less than 1
foot per year (1 x 10"6 centimeter per second [cm/sec]) at 55 percent of the MSWLFs, and
less man 10 feet per year (1 x 10"5 cm/sec) at 60 percent of the MSWLFs. However, at 21
percent of the MSWLFs, maximum permeabilities exceeded 100 feet per year (1 x 10^
cm/sec) (28 NMPs submitted data on maximum soil permeabilities).
Models were included in 60 percent of the NMPs. The 15 that included models all used
the Hydrologic Evaluation of Landfill Performance (HELP) model.
At 80 percent of the MSWLFs, the cost of an NMP was less than $30,000 (cost
information was available for 10 petitions).
Owners and operators that already have reasonable estimates of annual precipitation, annual
evapotranspiration, depth to groundwater, and maximum soil permeabilities for their MSWLFs can use
Table 2-1 to make a reasonable assessment of the probability of obtaining a no-migration exemption.
Figure 2-1 is provided to assist owners and operators who have such information. It is a decision tool
based on the data presented in Table 2-1. The four lettered bars in the figure show the various frequencies
at which values for each parameter were found in successful NMPs. To use the decision tool, follow the
instructions in the footnotes fo Figure 2-1.
Owners and operators that do not have reasonable estimates of annual precipitation, annual
evapotranspiration, depth to groundwater, and maximum soil permeabilities for their MSWLFs can collect
such estimates cheaply and then apply the decision tool presented in Figure 2-1. Those owners and
operators usually can obtain such values by contacting the sources of information shown in Table 2-2.
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TABLE 2-2: SOURCES OF SITE-SPECIFIC DATA ON KEY VARIABLES
USED TO EVALUATE NO-MIGRATION PETITIONS
Variable
Sources'
Depth to groundwater
Water resources investigation reports at U.S. Geological
Survey (USGS) regional libraries throughout the country.
USGS has published hundreds of detailed reports of
groundwater investigations. The reports show well locations.
State and local geologic and natural resources and soil
services offices and libraries.
Soil permeability
Water resources investigation reports at USGS regional
libraries throughout the country. USGS has published
hundreds of detailed reports of groundwater investigations.
The reports show well locations.
State and local geologic and natural resources and Soil
Service offices and libraries.
Annual precipitation
Publications of the National Climatic Data Center, National
Environmental Satellite Data and Information Service
(NESDIS), National Oceanographic and Atmospheric
Administration (NOAA), and U.S. Department of Commerce
(DOC).
State and local meteorological and agricultural offices and
services.
Local airports.
Annual evapotranspiration
Publications of the National Climatic Data Center, NESDIS,
NOAA, and DOC.
State and local meteorological and agricultural offices and
services
Local airports.
Infiltration
Publications of the National Climatic Data Center, NESDIS,
NOAA, and DOC.
State and local meteorological and agricultural offices and
services
Local airports.
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I
Figure 2-1: Decision Tool for Determining the Probability of a Successful NMP
Average
Annual
Preclusion
(Incheo)
Average
Annual
Evapo transpiration
(Inches)
16-25
10-15
0-9
<40
41-60
>60
F-1
B
1] To use this tool:
Probability
of
Success
F
A
I
R
G
O
O
D
H
I
G
H
E
X
c
E
L
L
E
N
T
Minimum
Depth to
Groundwater
(fust)
Maximum
Soil
Permeability
<50
51-200
>200
1-10
F-2
a) Find the values that correspond to your MSWLF on Bars A throughJD.
b) Draw a line from the value for your MSWLF on Bar A to that on bar b.
c) Repeat the above procedure and draw a line from Bar C to Bar D.
d) Draw a line from bar F-1 to Bar F-2 at the points of intersection from
your first two lines.
e) Read the center bar at the point of intersection of the line last drawn.
10
Draft
Do Not Cite or Quote
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In general, information about permeability will be the most difficult to collect from the sources listed in
Table 2-2. Usually, the owner or operator will receive a description of the type or types of soil that lie
between the ground surface and the uppermost aquifer the water table ~ at the MSWLF. Each
description should include an estimate of the thickness of the soil layer being described. If the sources
listed above decline to provide estimates of permeabilities, but will provide soil descriptions, Table 2-3 can
be used to estimate the permeability of each soil type.
Once the permeability and thickness of each layer of soil beneath the facility have been estimated, the
average permeability can be calculated by multiplying the thickness of each soil layer by its corresponding
permeability, adding the products, and dividing that sum by the total depth to the water table.
The decision tool provides a broad screening only. Its results should not discourage the owner or operator
from continuing to pursue an NMP, unless the site appears to be at an extreme disadvantage under all
criteria. In addition, the quality of the decision made by applying the decision tool in Figure 2-1 is related
directly to the quality of the estimates for each of the four parameters. However, it is not necessary to
obtain highly accurate estimates of the values for the MSWLF. Finally, if it would require too much time
or expense to find values for all the parameters in Figure 2-1, those that would require unreasonable
expenditures can be eliminated.
2.2.3 Estimation of Time of Travel
Another method of quickly and cheaply evaluating the probability that the NMP for an MSWLF will be
successful is to estimate the time required for hazardous constituents from the MSWLF to travel to the
water table. This method requires knowledge of the predominant soil type beneath the MSWLF and an
estimate of the net annual infiltration rate for precipitation at the MSWLF. Both parameters are available
from the sources listed in Table 2-2 (the U.S. Soil Conservation Service should be particularly helpful in
obtaining the information). When the net infiltration rate and the predominant soil textures.
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TABLE 2-3: PERMEABILITY RANGES FOR VARIOUS TYPES OF SOILS
Description1 , '-.-,'
Sandy gravels with very little fines
Silty gravels, gravel-sand-silt mixtures
Clayey gravels, gravel-sand-clay
mixtures
Sands and gravely sands with very little
fines
Silty-sands, sand-silt mixtures
Clayey sands, sand-clay mixtures
Inorganic silts and very fine sands, rock
flour, silty or clayey fine sands, clayey
silts with slight plasticity
Inorganic clays of low to medium
plasticity, gravelly clays, sandy clays,
silty clays, lean clays
Organic silts and organic silt-clays of
low plasticity
Inorganic silts, micaceous or
diatomaceous fine sandy or silty soils,
elastic silts
Inorganic clays of high plasticity, fat
clays
Organic clays of medium to high
plasticity, organic silts
C-.^, '-' :;K;.: £?^#=**>
:'.:.::v.'>:.:.'-..::-"-i'--:>.;hy£-v;?-
USCSfSoilCIassiii
"(USpA;S^ffCtess^:
GW and GP (GS)
GM(?)
GC(?)
SW and SP (S)
SM (FS, LS, LFS)
SC(?)
ML (SL, FSL)
CL (L, SIL)
OL(?)
MH(?)
CH(?)
OH(?)
Centimeters per
'?' -,*«'-" '* '"'WSj^f^-^WS'
>1.0xlO-2
1 x 10"* to lO'3
1 x lO'8 to 10-*
> 1 x lO'3
1 x lO"6 to lO'3
1 x 10'8 to 10*
1 x 10"6 to 10'3
1 x lO'8 to 10"4
1 x 10* to 10"4
.1 x ID"6 to 10"4
1 x 10'8 to ID"*
1 x 10'8 to 10-6
> 10,000
1 to 1,000
.01 to 1
> 1,000
1 to 1,000
.01 to 1
1 to 1,000
.01 to 100
1 to 100
1 to 100
.01 to 1
.01 to 1
Source: Agricultural Handbook Number 456, U.S. Departmentof Agriculture
1 The following definitions apply as used in these descriptions:
Sand is loose and single-grained. The individual grains can be seen or felt readily. Squeezed in the hand when dry, it will
fall- apart when the pressure is released. Squeezed when moist, it will form a cast, but will crumble when touched.
Sandy loam is a soil containing much sand, but which has enough silt and clay to make it somewhat coherent The
individual sand grains can be seen and felt readily. Squeezed when dry, it will form a cast that will fall apart readily, but if
squeezed when moist, will form a cast that will bear careful handling without breaking.
12
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Silt loam is a soil having a moderate amount of the fine grades of sand and only a small amount of clay, over half of the
particles being of the size called 'silt'. When dry, it may appear cloddy, but the lumps can be broken readily, arid when
pulverized, it feels soft and floury. When wet, the soil readily runs together and puddles. Either dry or moist, it will form
casts that can be_handled freely without breaking, but will give a broken appearance.
Clay loam is a fine-textured soil that usually breaks into clods or lumps that are hard when dry. When the moist soil is
pinched between the thumb and finger, it will form a thin 'ribbon' that will break readily, barely sustaining its own weight.
The moist soil is plastic and will form a cast that will bear much handling. When kneaded in the hand, it does not crumble
readily but tends to work into a heavy, compact mass.
Clay is a fine textured soil that usually forms very hard lumps or clods when dry and is quite plastic and usually sticky when
wet. When the moist soil is pinched between the thumb and finger, it will form a long, flexible 'ribbon.' Some fine clays
very high in colloids are friable and lack plasticity in all conditions of moisture.
Loam is a soil having a relatively even mixture of different grades of sand and of silt and clay. It is mellow, with a somewhat
gritty feel, yet fairly smooth and slightly plastic. Squeezed when dry, it will form a cast that will bear careful handling, while
the cast formed by squeezing the moist soil can be handled quite freely without breaking.
The Unified Soil Classification System is one of two nationally recognized and widely used systems for estimating soil
properties. The other is the USDA scale, which also is based on the soil texture and the various percentages of sand, silt, and
clay. Therefore, the descriptions of a soil's texture can be used to classify it under either system and to convert from one
system to another.
To convert cm/sec to ft/yr multiply by 1,034,645.6. Thus, 1 x 10"* cm/sec equals approximately 1 ft/yr.
13
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at the MSWLF are known, Table 2-4 can be used to estimate the minimum depth to groundwater necessary
for a no-migration exemption at an MSWLF that will operate for 30 years and undergo post-closure care
for an additional 30 years. It should be noted that the use of Table 2-4 will yield conservative results at
sites that have permeabilities of less than 17 feet per year. (The method used to construct the table is based
on equations taken from the Superfund Site Assessment Manual [EPA 1988].)
23 Content of an NMP
The previous sections of this chapter described how to apply limited and inexpensively gathered
information to determine whether an NMP can be expected to be successful. This section suggests the
specific types and amounts of information that state officials will expect to see before making a decision
about a no-migration exemption. Officials typically responsible for such matters include individuals
having such titles as solid waste engineer, solid waste management official, or director of a solid waste
permit section. To contact such officials, call the headquarters of the state department of environmental
protection and ask for the office of solid waste. Make an appointment to visit with an official of that
office. Ask whether the state has specific guidance for NMPs or any written decision criteria that can be
obtained before the meeting. Explain to the state official the need to know exactly what types of data must
be submitted. Be prepared to answer questions about the MSWLF. In addition, inform the official of the
location and design of the MSWLF and its waste acceptance rate. Ask whether any characteristics of the
MSWLF would increase or decrease the probability that it will receive a no-migration exemption.
The previous section described information that a state might require be included in a no-migration
petition. Those and other types of information are shown in Table 2-5, a data collection form for keeping
track of the information needed for the NMP. It is important that the information recorded be as complete
and accurate as possible because that information will be used to estimate the probable total costs of
preparing the NMP.
14
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TABLE 2-4: MATRIX FOR DETERMINING THE VELOCITY OF MIGRATION
OF HAZARDOUS CONSTITUENTS TO THE WATER TABLE1
(Page 1 of 2)
Average Annual Net
Infiltration or*'
Percolation Rate2
KodttSf^
Yeair ~-
1
5(3.8)
10
15
20
1
5(3.7)
. 10
15
20
1
5(3.6)
10
15
20
' W
.0834
.417 (.32)
.834
1.25
1.67
.0834
.417 (.31)
.834
1.25
1.67
.0834 .
.417 (.3)
.«34
1.25
1.67
i v f- ~t >- -!
> <- > «
1 * Soil Texture " ^
(Permeabil% Value tfsed
in Calculating Vdoci^jt in
Sand (6,000)
Sandy loam (745)
Silt loam (196)
Miniinum Depth to the
Water Table for a
MSWLF With a 60-year
;: Total Operating life and
Bosi|3osn|»,!C8r^ ^iriodt
36
150(120)
282
408
529
24
102(78)
198
288
372
18
80 (60)
156
222 .
194
« ^<~ " *~ /
^ ' Velocity of^y^
* Contaminant Migration
.6
2.5 (2.0)
4.7
6.8
8.8
.4
1.7(1.3)
3.3
4.8
. 6.2
.3
1.3(1.0)
2.6
3.7
4.9
15
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TABLE 2-4: MATRIX FOR DETERMINING THE VELOCITY OF MIGRATION
OF HAZARDOUS CONSTITUENTS TO THE WATER TABLE
(Page 2 of 2)
Average Annual Net
Infiltration or
Percolation Rate2 >
Inches per
; YearC:
1
5 (3.45)
10
15
20
1 (1.7)
5
10
15
20
Feet per
Year,
.0834
.417 (.28)
.834
1.25
1.67
.0834 (.15).
.417
.834
1.25
1.67
f
-HJT >-
Soil Texture
(Permeability Value Used
in Calculating Velocity in
FeetperYear)* -
Clay loam (66)
Clay (17.5)
s ^ »ij
MuiinHnn Depth to the
Water Table for a
MSWLF With a 60-year
Total Operating life and
Post-Closure Care period
(Feet) t " *
1
, 66(48)
132
192
253
12(24) .,
60
114
174 ,
228 ,'
* *
* * *
* » j-
, ; Yeioc|lyof^ - *"
Contaminant Migration
(EeetpeBYear)^./
.2,
1.1(0.8)
2.2.
3.2
'4.2
.2(0.4)
1.
1.9
2.9
3.8
This table was adapted from instruction for calculating the velocity of infiltrating rainwater in the Superfund Exposure
Assessment Manual," Office of Remedial Response, EPA (EPA/540/1-88/011).
You can obtain net infiltration or percolation rates for your area by contacting the local offices of the U.S. Soil Conservation
Service or your state geological survey office. The rate is equal to the total annual average precipitation rate, minus losses of .
moisture through runoff and evapotranspiration. The infiltration rates in bold face type shown in parentheses in the table
represent conservative estimates that can be used in lieu of site-specific data. The estimates were derived by assuming an
annual average precipitation rate of 25 inches per year, minus values for surface runoff and evapotranspiration rates taken
from Table C-8 in Hydrologic Simulation on Solid Waste Disposal Sites, Office of Water and Waste Management, EPA
(SW-868), September, 1980. If your know your average annual precipitation rate and you are in a relatively dry area, you can
assume that-only IS percent of the average annual precipitation will infiltrate. That assumption represents conservative
values of 15 percent runoff and 70 percent evapotranspiration rates.
Note that these permeabilities are higher than those measured in many clayey soils; therefore, they contribute to a
conservative estimate of velocities at sites that have clayey soils.
Calculations of velocities of migration of contaminants were based on the following formula:
V-q/p
where: '
q = Average percolation or recharge rate (depth per unit time)
p = Volumetric moisture content of the unsaturated zone (decimal fraction representing volume of water per volume of soil)
The values used to represent "p" above were specific for each soil texture shown in the table and originally were derived
through laboratory tests en numerous soils-having those textures, as reported in the Superfund Exposure Assessment Manual.
16
-------
TABLE 2-5: NMP DATA COLLECTION FORM
(Page 1 of 2)
Depth to grouhdwater
B
i
V
.50
4
Soil permeability
(hydraulic conductivity)
Soil porosity
Bulk density of soil
Moisture, content of soil
Moisture content of
waste
Soil moisture at field
capacity
Soil moisture at the
wilting point
Soil classification/soil
texture
Models (list type[s])
Maximum depth of
MSWLF
Average annual
precipitation
Average runoff rate
17
Draft
.Do Not Cite or Quote
-------
TABLE 2-5: NMP DATA COLLECTION FORM
(Page 2 of 2)
- ' ' ;" "' - -i r.-?
Infiltration or percolation
rate
Average annual
evapotranspiration rate
Thickness of liner (each
material)
Permeability of liner
(each material)
Thickness of cover (each
layer)
Permeability of coyer
-
".'-
* " -
' * '. - *'...* , - , - , .'' .-.."
- ... -,..,. -.*:> . * . , ,-,i ... , .
#.*:",'' '"' ''* '" "-' : '""*'" , .;r'x\,:;'' ';':'!" " '.; ;', "
*>:?> *;"""'- :.*:: "*-'-:''' *' '-"-:.V'':V "-'; ./ " '..'. '
Nrt«mtijn
-------
During the meeting with the state official, verify that all the written guidance and forms necessary to
complete the NMP have been provided. Review each type of data listed in Table 2-5 and ask whether it is
required. If a particular type of data is required, ask whether the information must be determined from oh-
site measurements or whether the results of similar measurements taken at nearby facilities are sufficient.
As an alternative, ask whether values in the literature that describe the general hyrogeologic setting in the
area can be used in place of on-site measurements for certain items. Ask for recommendations of any
specific literature that provides values for particular data elements. For data that must be collected on a
site-specific basis, ask whether there is a minimum number of samples that must be collected. In addition,
ask whether there is a minimum number of borings that must be drilled to collect data on certain
parameters and how deep the borings must be.
Be certain to ask the state official whether there are any types of data that are not listed in Table 2-5 that
must be included in the NMP. List the additional items in the blank spaces in the table, and complete all
columns of the table for those items, just as the other items in the table.
Finally, ask the state official which, if any, hydrogeological models must be ran to demonstrate the
migration rates of hazardous materials from the MSWLF. Ask whether the state will perform such models
and whether officials can use default values and to make a decision about the MSWLF without requiring
the submittal of an NMP. Determine whether the state has predesignated certain portions of the state as
good or poor locations for candidates for no-migration exemptions.
After Table 2-5 has been completed, the next step is to develop a ballpark estimate of the costs of
completing an NMP for the MSWLF. The next chapter of this manual is a guide to completing that task.
19
-------
3.0 STEP 2: ESTIMATE AND ANALYZE THE COST OF THE NMP
This chapter includes Two sections. Section 3.1 presents an approach to determining a ballpark estimate of
«
the costs of preparing an NMP. Section 3.2 presents an approach to determining whether the preparation
of a petition is cost-effective in any particular case.
3.1 Estimate the Cost of an NMP
Using the data collection form filled out as described in Section 2.3 (see Table 2-5), identify the
information that already has been collected. For example, much of the information needed might be found
in the permit application for the MSWLF. Next, identify the information listed on the data collection form
(Table 2-5) that the state will allow to be obtained from literature. In many cases, an owner or operator can
obtain literature free or for a nominal fee from local, state, and federal government sources and from
universities. Assume that the cost of obtaining each source of information is $150.00, except for
information that obviously will require little time to collect. (The figure of $150.00 is based on the
assumption that it would require approximately four hours of a junior consultant's time, and $50.00 in
other direct costs, to retrieve information from each literature source.) Some of the information needed for
a particular site may not be available in the literature; therefore, it may be necessary to revise the cost
estimate after a review of information from the vatious sources suggested by the state solid waste official.
After entering on the data collection form the information from literature, review the types of information
listed on the form that must be collected at the MSWLF through sampling. Use Table 3-1 to prepare a
ballpark estimate of the cost of each such item. If items required by the state are not listed in Table 3-1,
obtain estimated unit prices from local soil laboratories, local drillers, consulting firms, state officials,
universities, or owners or operators of nearby MSWLFs where such testing has been performed. The
estimate will be much more accurate if such contacts provide information to support die estimates of the
costs of all the items listed in Table 2-5. However, the rates listed in Table 3-1 can be used to construct a
quick ballpark estimate before making telephone calls to refine the unit costs upon which the estimate
would be based.
20
-------
TABLE 3-1: RATES FOR COSTING VARIOUS ON-SITE MEASUREMENTS
THAT MAY BE REQUIRED BY THE STATE (1996)
(Page 1 of 2)
** J *
Types of Data -^
Depth to groundwater
Soil permeability
(hydraulic conductivity)
Soil porosity
Bulk density of soil
Moisture content of soil
Moisture content of waste
Soil moisture at field
capacity
Soil moisture at the wilting
point
Soil classification/soil
Texture
Models Gist type[s])
Maximum depth of
MSWLF
Average annual
Precipitation
Average runoff rate
Infiltration or percolation
rate
Average annual
evapotranspiration rate
Thickness of liner (each
material)5
Permeability of liner (each
material)
Thickness of cover (each
layer)
Procedure
Drilled boring
Laboratory
test
Laboratory
test
Laboratory
test
Laboratory
test
Laboratory
test
Laboratory
test
Laboratory
test
Laboratory
test
Computer
analysis
Drilled boring
NA
Field:
measurement
Field
measurement
NA
Drilled boring
Laboratory
analysis
Hand
augering
Unit Cost
$30/foot2 -
$100/test
$25/test
$25/test
$25/test
$25/test
$25/test
$25/test
$25/test
$2,OQO/
analysis3-
$20/foot4
NA
$100
$100
NA
$20/foot6
$100/Test
$500
_, t « - _ <-
"°" *» »
Number Required1
1
NA
NA
Total
, Coat
$2,000
NA
NA
21
-------
TABLE 3-1: RATES FOR COSTING VARIOUS ON-SITE MEASUREMENTS
THAT MAY BE REQUIRED BY THE STATE
(Page 2 of 2)
Types of Data
Permeability of .cover
TOTAL COSTS
Procedure
Laboratory
analysis
NA
Unit Cost.
$100/test
NA
\ f ti ». ? * .* ' **a ** * **f* S
* *f v? f f at f
Number Required
NA
Total
Cost '
The number of measurements needed for each data type often is expressed in terms of the depths of the borings to be made.
Therefore, it is important to consider both the total depth and the number of borings when estimating the total number of each
test to be conducted at your MSWLF.
This" unit cost is based on the assumption that the boring will be six inches in diameter, will exceed 1.00 feet in depth, and
will be drilled with an air rotary drill by a three-man crew consisting of one operator and two unskilled laborers, and that the
boring will be cased, capped, and fitted with a concrete pad. The diameter of six inches is recommended for borings done at
your site because such borings can be converted into groundwater monitoring wells if the NMP is not successful. The added
cost of that approach is approximately $10 per foot
Assumes that data already have been collected and are available to the modeler. Also assumes 24 hours of a junior modeler's
time and 8 hours of a senior modeler's time, plus materials.
The diameter of the boring is assumed to be two inches.
It is not likely that many states will require this test because it could jeopardize the integrity of the containment structures .of
theMSWLF. , .
The diameter of this boring is assumed to be two inches.
NA = Not Applicable
22
-------
After completing Table 3-1, add the costs and record the total at the bottom of the right-hand column. Add
that figure to the total cost estimated for collection of the information that can be obtained from literature.
Add to the new total $5,000 to retain a consultant to communicate with the state, analyze information
about your site, and prepare the NMP. In most cases, the consultant should be able to perform those tasks
for less than that amount; however, a ballpark estimate should err on the high side rather than the low.
The total cost of groundwater monitoring calculated as described above should be compared with the
estimated cost of preparing an NMP. In many cases, preparing an NMP costs far less than groundwater
monitoring.
3.2 Analyze the Cost of the NMP
Once a reasonable estimate of the costs of the NMP has been prepared, compare that amount with the cost
of installing a groundwater monitoring system and monitoring the groundwater over the active life of the
MSWLF, plus the post-closure care period. To estimate the cost of installing a groundwater monitoring
system:
Multiply $90 by the depth to groundwater at the site, and multiply the result by the
number of wells that are likely to be needed. (A state solid waste official will be able to
provide an estimate of the number of groundwater monitoring wells that may be needed at
a given MSWLF.)
Add to that number $600 per well per year for 30 years of post-closure care at the
MSWLF.
Add to that figure $1,800 per well for the first year of monitoring, plus $600 per well for
each remaining year of operation of the MSWLF.
For example, groundwater monitoring at a facility that has three, 200-foot-deep wells and 20 years of
remaining active life would cost a total of $147,600. In addition, at least 60 hours of consulting time
would be needed for well design and placement and oversight, estimated at approximately $5,000,
bringing the total costs of groundwater monitoring for the facility to $152,600. The cost of an NMP for the
same facility could be expected to be approximately $15,000, assuming that only one boring is required
and that all soil tests would be repeated at 20-foot intervals. That cost should be reduced by the cost of the
boring (approximately $6,000), because the boring can be used to install a groundwater monitoring well
should the NMP be unsuccessful. Therefore, for a MSWLF that meets the description above, an NMP can
be prepared for approximately $9,000, or six percent of the cost of installing and operating a groundwater
23
-------
monitoring system. Such differences between the costs of groundwater monitoring and those of preparing
an NMP are expected to be common to most, if not all, MSWLFs. In addition, the approach described in
the following chapter allows the owner or operator to recognize at the .earliest possible point that an NMP
is likely to be unsuccessful, so that the effort can be abandoned before large expenditures of time and effort
are made.
24
-------
4.0 STEP 3: FOLLOW COST-EFFECTIVE METHODS OF PREPARING THE NMP
The following three steps are the most cost-effective approach to preparing an NMP:
Prepare a clear written description of needs and discuss those needs with state solid waste
officials
Discuss the needs with consulting firms that specialize in the field
Using standard practices, select a consultant
The three steps are discussed in the following subsections.
4.1 Prepare a Clear Written Description of Needs
This step was completed substantially during the visit with the state solid waste official. However, it is
important to document all the information that will be needed for an NMP in a one- or two-page
description supported by a table similar to Table 2-5. Once that description has been prepared, it may
become apparent that there are some areas of uncertainty concerning the number or types of tests that must
be reported in the NMP. However, even if there are no information gaps in the description, an attempt
should be made to obtain comments on the information required in an NMP. In addition, attempt to obtain
comments from those officials on the types of information that will be crucial to their decision and the
types of information that almost certainly will cause the rejection of an NMP. Explain that the rationale for
asking such questions is to limit expenditures for consultants to complete the NMP by terminating the
preparation of the NMP at the earliest indication that it will not succeed. Use the results of the discussions-
with state officials to determine whether to engage a consultant to prepare the NMP. Some states may
have in place formal or informal procedures for analyzing information about MSWLFs in such a way that
only the raw data on an MSWLF must be presented to them. In those states, a consultant might not be
needed to prepare the petition. However, use of a consultant to oversee the collection of arty field data
required by the state is recommended.
4.2 Discuss Needs With Consulting Firms
Contact three or more consulting firms mat specialize in hydrogeological evaluations. Such firms are listed
in local telephone directories; however, it is best to obtain recommendations of competent firms from state
officials or from other owners or operators of MSWLFs. Call each firm and ask to speak with a senior
25
-------
hydrogeologist. Explain to that person that you are considering submittal of an NMP for a MSWLF, and
ask to speak with the appropriate person in the company. Describe to that person pertinent facts about the
MSWLF its size, the depth to groundwater, and the climate and explain the information needs
identified in cooperation with state officials. Agree to provide the firm with an invitation to bid on the
preparation of the NMP, if the firm is interested. Ask each firm about its experience in preparing such
petitions, and encourage the contact to offer an opinion about the probability that the NMP will be
successful. Ask each contact to comment on whether the information about data needs identified appear to
be complete and accurate, in light of the firm's experience. Discuss any major discrepancies related to
information needs with state officials. Ask them to reconfirm the need for information that one or more
consulting firms believed to be unnecessary, or to reconfirm that there is no need for information that one
or more consulting firms believed to be crucial.
4.3 Select a Consultant
Prepare an invitation to bid for three or more consulting firms believed to be reputable, in light of the
recommendations of past clients and the opinion formed during telephone conversations with their staffs.
The invitation to bid should state clearly exactly what is expected of the contractor in preparing the NMP.
It is recommended that each contractor be required to provide a brief summary of the experience of its staff
and its company in preparing such petitions, both successful and unsuccessful. In lieu of such experience,
a contractor should explain how the experiences of its staff and its company are relevant to the preparation
of a successful NMP. In addition, the bid package should request that each contractor describe specific
criteria that could be used to trigger the abandonment of the NMP at any of a number of stages in the
preparation process. Such a step-by-step approach could reduce the cost of preparation of an NMP by
allowing the owner or operator to cease such efforts if success begins to appear unlikely. For example, a
company may propose to conduct a visual evaluation of coring samples from borings at the site and make a
decision about whether to proceed with the preparation of the petition. Such interim evaluations could
produce significant savings at sites for which more than one boring or numerous laboratory tests on soil
samples are needed to support an NMP. At the very least, each firm should be asked to provide a subtotal
of costs for collection and presentation of all required information, with a preliminary conclusion about the
probability that an NMP would be successful. Such an approach, could save the cost of preparing a petition
in cases in which there is very little probability of success.
The instructions in the bid package should state clearly how the firm awarded the contract will be selected.
For example, -the owner or operator may elect to use three criteria, such as experience, approach, and total
26
-------
cost, in evaluating the bids. In such a case, each of the bidders would be rated on a scale of 1 to 10 for its
responses to each of the evaluation criteria. For example, a total cost that is twice the amount of the lowest
offer might receive a rating of 2 and a bidder that proposes three or more decision points that collectively
have the potential to save 50 percent of the total estimated cost of the project might receive a rating of at
least 8. Next, the score of each bidder under each criterion would be multiplied by a weighing factor that
represents the relative importance of that criterion in the evaluation. Finally, the results in each category
would be added to obtain a total score for each bidder. The bidder having the highest score should be
selected for negotiations to encourage the bidder to reduce its costs or increase its proposed activities. In
all cases, it is important to maintain control over the evaluation process, so that no bidder is selected if
none meets the requirements.
27
-------
Appendix
Information Used to Analyze
No-Migration Petitions
in Seven States
-------
Table A-l
CRITERIA USED BY STATES TO MAKE DETERMINATIONS ABOUT NO-MIGRATION EXEMPTIONS
(Page 1 of 3)
State
Regulatory Criteria Used to Make Determination
References
Arizona
Exemption from groundwater monitoring requirements
Demonstration that there is no potential for migration of
hazardous constituents frorn that MSWLF to. the uppermost aquifer
- Measurements collected at specific field sites and sampling and
analysis of physical, chemical, and biological processes affecting
the fate and transportation of contaminants
- Predictions of the fate and transport of contaminants that maximize
migration of contaminants and a consideration of the effects on
public health and safety and the environment
Certification by a qualified groundwater scientist
Approval by the director of the Department of Environmental
Quality
40 CFR 258.50(b)(l)(2)
Idaho
Exemption from groundwater monitoring requirements
Demonstration that there is no potential for migration of hazardous
constituents from the landfill to the uppermost aquifer during the
active life of the unit and the post-closure care period
Certification by a qualified groundwater scientist
* Approval by the director of the Idaho Environmental Council
Solid Waste Facilities
Act, Title 39, Chapter
7410
Montana
Exemption from groundwater monitoring requirements
Demonstration that there is no potential that hazardous constituents
will contaminate the uppermost aquifer
Provision of facility-specific data and studies certified by a qualified
groundwater scientist:
- Site-specific, field-collected measurements, sampling, and analysis
of physical, chemical, and biological processes affecting
contaminant fate and transport
- Predictions of contaminant fate and transport that maximize
migration of contaminant and consider effects on human health
and the environment
Demonstration that groundwater will not become contaminated for at
least 30 years after the facility is closed
Installation of vadose zone monitoring devices, piezometers, or
saturated zone monitor wells as required by the department as part of
an ongoing no-migration demonstration
Solid Waste Management,
Subchapter 7,
16-793)
28
-------
TABLE A-l
CRITERIA USED BY STATES TO MAKE DETERMINATIONS ABOUT NO-MIGRATION EXEMPTIONS
(Page 2 of 3)
State
Regulatory Criteria Usedto^ Maske Determuiafiofc
References
Nevada
Exemption from groundwater monitoring requirements:
Demonstration that there is no potential for migration.of hazardous
constituents from that unit to the uppermost aquifer during the active
life of the unit, including the period of closure and post-closurecure
- Site-specific measuremerits and the sampling and analysis of
physical, chemical, and biological processes affecting the fate and
transport of contaminants
- Predictions of the fate and transport of contaminants that are based
on the maximum possible rate of migration of the contaminant and
consideration of the effects.on public health and safety and the
environment
Certification by a qualified groundwater scientist
Approval by the solid waste management authority
Solid Waste Disposal,
General Provisions,
444.748 l(a)(b)
(p.444-116)
New
Mexico
Exemption from part or all of groundwater monitoring
requirements under Sections 802 to 806:
Demonstration that there is no potential for migration of hazardous
constituents from the landfill to the uppermost aquifer during the
active life and the post-closure care period
- Site-specific field measurements and sampling and analysis of
physical, chemical, and biological processes affecting fate and
transport of contaminant(s)
- Predictions of the fate and transport of the contaminant(s) that
maximize migration of the contaminants) and consideration of the
effects on public health and welfare and the environment
Certification by a qualified groundwater scientist
» Approval by the secretary of the Department of the Environment
Solid Waste Management
Regulations, Part VIII,
801.C.1.2 (p. 103)
29
-------
TABLE A-l
CRITERIA USED BY STATES TO MAKE DETERMINATIONS ABOUT NO-MIGRATION EXEMPTIONS
(Page 3 of 3)
State
Regulatory Criteria Used to Make Determination
References
Utah
Exemption from groundwater monitoring requirements:
. Demonstration that there is no potential for migration of hazardous
substances from the facility to the groundwater during the active life
of the facility and the post-closure care period
- Site-specific, field-collected measurements and sampling and
analysis of physical, chemical, and biological processes affecting
fate and transport of the contaminant(s)
- Predictions of the fate and transport of the contaminant(s) that
maximize migration of the contaminant(s) and consideration of the
effects on human health and the environment
Certification by a qualified groundwater scientist
Approval by the Executive Secretary
Exemption from some design criteria and groundwater monitoring
requirements (new or existing facilities that are seeking expansions)
Requirement that the MSWLF be located over an area where:
- Groundwater has total dissolved solids (TDS) of 10,000 milligrams
per liter (mg/L) or higher
- There is extreme depth to groundwater
- There is a natural impermeable barrier over groundwater
- There is no groundwater
Solid Waste Permitting
and Management Rules.
R315-308rl(3)(a)(b)
(p. 22)
R315-3d2-l(2)(vi)
Wyoming
Exemption from groundwater monitoring requirements,
Type I landfill:
Demonstration that there is no potential for migration of hazardous
constituents from the facility to the uppermost aquifer
- Site-specific field measurements
- Information about the specific wastes to be disposed of at the
facility
- Predictions of fate and transport of contaminants, including use of
the hydrologic evaluation of landfill performance model, that
maximize migration of contaminants and consider effects on
human health and the environment
Type II landfill:
Groundwater monitoring systems are not automatically required for
Type n landfills, but may be required after the department reviews the
permit application
Solid Waste Rules
and Regulations
Chapter 2, Section 6
30
-------
TABLE A-2: VALUES FOUND FOR KEY1 PARAMETERS IN SUCCESSFUL NO-MIGRATION PETITIONS FOR SPECIFIC MSWLFS IN ARIZONA
(Page 1 of 8)
Name of
Facility
Cerbat
Size (acres) and
Disposal Rate
(Ions/day)
160; NI
Active Life of Facility
(vrY ','-
30-40
Thickness and Permeability
of Dally Cover
6 in; compacted cover material
Depth to
Groundwater
(ft)
18-160
Average Permeability
of Soil or Hydraulic
Conductivity
Silly and gravelly sand;
1.23x10* sec* (sandy
loam)
Annual Precipi-
tation Rate '(in)
10
Annual
Evapotranspiration
Rate (in)
76
Models Used
HELP, vers.
2.05,
WHPA, vers.
2.0 (RESSQC)
Cost To
Prepare
Petition
($)
NI
4, 100 to
5,000"
Note:
0) The term "key" as used here reflects PRC Environmental Management Inc.'s current best estimate of those items that may have been addressed by the state' in granting no-migration exemptions. The items were determined through
review of facility documents and other documents in the possession of the state. The parameters shown in this table are subject to change after further analysis.
NI Information not included
* Typical"hydraulic conductivity for a sSndy loam was used for the Hydrologic Evaluation of Landfill Performance (HELP) program.
** The cost to produce the petition is unclear. Modeling was being done for various reasons when it was decided to apply for a no-migration petition. At that point, substantial information was available to be included in the petition, thereby
keeping the cost to a minimum.
31
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TABLE A-2: VALUES FOUND FOR KEY1 PARAMETERS IN SUCCESSFUL NO-MIGRATION PETITIONS FOR SPECIFIC MSWLFS IN IDAHO
(Page 2 of 8)
Name of
Facility
Clay Peak
Lemhi County
Landfill
Pickles Bulte
Size (acres) and
Disposal Rate
(tons/day)
120; 44.45
16.5; NI
370; NI
Active Life of
Facility (yr)
68
>40
>200
Thickness and Permeability of
Daily Cover
6 in; fine-grained soil
6 in; any soil type
6 in; fine-grained soil
Depth to
Ground water
(ft)
297.9 to 334.9
>325
>400
Average Permeability of
Soil or Hydraulic
Conductivity
1.4xlOJ'lo4.2xlO-4
cm/sec;
UxlO'5to4.0xl018
cm/sec; 1.7 to 3 inches per
foot of soil
Clay with high plasticity;
1.8x10" to 3.6x10-'
cm/sec
NI;
1.0x10^ to 1.8x10*
cm/sec
Annual
Precipi-tation
Rate (in)
10.21
9.39
6-8
Annual Evapotranspi-
ratiori Rate (in)
59.85'
30
50
Models Used
HELP,
CHEMFLO,
MULTIMED
HELP ver. 2.0,
CHEMFLO,
SUTRA
HELP
Cost To Prepare
Petition
($) '
approx. 240K.
84K*
25Kto30K
Note:
(l) The term "key" as used here'reflects PRCs current best estimate of those items that may have been addressed by the state in granting no-migration exemptions. The items were determined through review of facility documents and other
documents in the possession of the state. The parameters shown in this table are subject to change after further analysis,
NI Information not included
* This cost is a factor in the cost of a no-migration petition. The cost actually incorporates overall design of the landfill, as well as design of the collection system.
32
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TABLE A-2: VALUES FOUND FOR KEY1 PARAMETERS IN SUCCESSFULNO-MIGRATION PETITIONS FOR SPECIFIC MSYVJLFS IN MONTANA
350
Average Permeability of
Soil or Hydraulic
Conductivity
Vertical mitigation rale of
gw: 0.2-23ft/yr,8.11x
10'* cm/sec
N!;NI
Tight soils approx.
permeability = 10* or 10'7
cm/sec; NI
9.5 xW cm/sec; NI
5.1- 9.6 xlO'8 cm/sec;
4.63 xlO'7 cm/sec
I x 10s to
1 x 1C"4 cm/sec;
1 x lO'4 cm/sec
Annual Precipi-
tation Bate (in)
14
10.64
14
12.3
11
9.53
Annual Evapotrunspi-
ralion Rate (in)
45
NI
NI
NI
NI
48
Models Used
Not used
Not used
Not used
1
Not used
Not used
Not used
Cost To Prepare
Petition (S)
25K
NI
*5K + 2yrs.
4565.45
18K initial study;
$9,935-secondary
study & no-mig.
recommended
8Kto9K
Note:
(l) The term "key" as used here reflects PRCs current best estimate of those items that may have been addressed by the state in granting no-migration exemptions. The items were determined through review of facility documents and other
documents in the possession of the slate. The parameters shown in this table are subject to change after further analysis.
NI Information not included
* $5,000 was spent on the engineering portion; however, an unrecorded two or more years of personal time wee expended on the project.
33
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TABLE A-2: VALUES FOUND FOR KEY1 PARAMETERS IN SUCCESSFUL NO-MIGRATION PETITIONS FOR SPECIFIC MSWLFS IN NEVADA
(Page 4 of 8)
Name of Facility
City of Mesquile
Municipal Waste
Landfill
Size (acres) and
Disposal Rat*
(tons/day)
40; NI
Active Life of
Facility (yr)
NI
Thickness and
Permeability of Daily
Cover
> 6 in; compacted cover
material
Depth to Groundwater
(fl)
>400
Average Permeability of
.Soil or Hydraulic
Conductivity
1 x 10"8 cm/sec (silt & clay)
and 1 x 103 - 1 x 10^
cm/sec (fine sands); NI
Annual Precipi-
tation Rate (in)
4.1
Annual
Evapotranspi-ration
Rate (in)
NI
Models Used
HELPII,vers.
2.5
Cost To
Prepare
Petition
($)
NI
Note:
(1) The term "key" as used here reflects PRCs current best estimate of those items that may have been addressed by the slate in granting no-migration exemptions. The items were determined through review of facility documents and other
documents in the possession of the state. The parameters shown in this table are subject to change after further analysis.
NI Information not included
* 26.5 acres were used as final design footprint area for the HELP program.
34
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(PageS of 8)
Name of Facility
Conalilos Landfill
Size (acres) and Disposal
Rate (Ions/day)
480 (East phase: 200 acres);
350
Active Life of
Facility for)
20 (East phase)
Thickness and
Permeability of Daily
Cover
6in;NI
Depth to
Groundwater
(ft)
>430
Average Permeability
of Soil or Hydraulic
Conductivity
1.0 xlfl-1 cm/sec; NI
Annual Precipi-
tation Rate (in)
9.56
Annual livapotranspi-
ration Rate (In)
93.95
Models Used
HELP
Cost To
Prepare
Petition
(S)
10K anil public
hearing ctisls
Note: (
'" The term "key" as used here reflects PRCs current best estimate of those items that may have been addressed by the stale in granting no-migration exemptions. The items were determined through review of facility documents and other
documents in the possession of the stale. The parameters shown in this table are subject to change after further analysis.
NI Information not included
* The active life of a cell, 1.8 years, is estimated from the information about the active life of the East Phase (20 years) and total number of fills (11 fills) in the East Phase.
35,
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TABLE A-2: VALUES FOUND FOR KEY1 PARAMETERS IN SUCCESSFUL NO-MIGRATION PETITIONS FOR SPECIFIC MSWLFS IN UTAH
(Page 6 of 8)
Name of
Facility
Millard County
Landfill
Long Hollow
Sanitary Landfill
Size (acres) and
Disposal Rale
(tons/day)
80; 20-25
NI;NI
Active Life of Facility
(yr)
200'
20+
Thickness and
Permeability of Daily
Cover
6 in; compacted cover
material
6 in; 3 x 10'3 cni/sec
Depth to Groundwater
(tt)
35-80
>300
Average Permeability
of Soil or Hydraulic
Conductivity
6 x ID* to
1 xlO'8 cm/sec; Nl '
1.9 xlO* cm/sec; Nl
Annual Precipi-
tation Rate (in)
6 to > 25
<10
Annual Evapotranspi-
ration Rate (in)
60
50
Models
Used
HELP 11,
vers, 2.05
WHPA
HELP
Cost To
Prepare
Petition
($)
18K
Nl
Note:
10 The term "key" as used here reflects PRCs current best estimate of those items that may have been addressed by the state in granting no-migration exemptions. The items were determined through review of facility documents and other
documents in the possession of the state. The parameters shown in this table are subject to change after further analysis.
Nl Information not included
* The active life of facility is estimated from the information about the size of the facility (80 acres) and the size (0.8 acre) and active life! (two years) of each cell.
A-36
-------
TABLE A-2: VALUES FOUND FOR KEY1 PARAMETERS IN SUCCESSFUL NO-MIGRATION PETITIONS FOR SPECIFIC MSWLFS IN WYOMING
(Page7of8)
Name of Facility
Manderson Sanitary H\
Fl. Laramic Landfill
Shell Sanitary #2
Landfill
Green Rive: #1
Landfill
Rock Springs Sanitary
#1 Landfill
Sublette County
Marbleton Sanitary #2
Landfill
Teton County
Horselhief Canyon
Sanitary #2
Washakie County
Worland Sanitary #2
Landfill
North Big Horn
County Landfill #2
TownofHuletl
Sanitary Landfill
Ten Sleep Sanitary #1
Landfill
Central Weston County
Landfill
FCSWDD
Missouri
Valley Sanitary
Landfill
Uper Plait River
SWDD
Hudson Sanitary #1
Lindlill
Size (acres) and
Disposal Rate
(tons/day)
2.5 acres
<1
.3.12 acres
<1
5.0 acres
40';47.52
47; 273s
40; 52'
70; 23 to 55"
40'"; 94.713
136.9; 18.9
14.1 acres
<-2
22.96 acres
5.75 acres
20.08 acres
6.85 ions/day M
NL'l.28"
8.57 acres; NI
Active Life of Facility
(yr)
12
12
13
10
4
15
15 to 20
8
49
SOyrs.
21 years
24
30
33.1
3.25
Thickness and
Permeability of Dally
Cover
6 in
1-6 xlO'7
6 in; 0.0038 to
9-4 x 10* cm/sec
6 in
6-7 xlO*
6 in; sandy, rocky loam
6 in; compacted earth
6 in; NI
NI
6 in
NI
6 in; NI
6 in; 2 x 10* cm/sec
6 in
l.OxlO'5
6 in; NI
6 in computed, despoisted
weekly; NI
6in;NI
Depth to Groundwater
(ft)
>225
75-100 ft
230
> 130 (no gw
encountered)
52to>100»
80'°
> 110 (no gw encountered
at least 200-300 ft
est. > 160 ft (no gw
encountered during
drilling)
Three separate gw
systems
600 -700 ft
115
>550
>61.5
25 to 35
>61.5
Average Permeability
of Soil or Hydraulic
Conductivity
1-6x10'
0.0038to9-4xIO'
cm/sec
6.7x10"
5xl03lo
-------
TABLE A-2: VALUES FOUND FOR KEY' PARAMETERS IN SUCCESSFUL NO-MIGRATION PETITIONS FOR SPECIFIC MSWLFS IN WYOMING
(Page 8 of 8)
Name of Facility
Sublette County
Pinedale Landfill
Upton #4 Type II
Sanitary Landfill
Upton #4 Type II
Sanitary Landfill
Bridger Valley Sanitary
#1 Landfill
Size (acres) and
Disposal Rate,
(tons/day)
60.86 acres/<20
20 acres/ 3.57"
20 acres/ 3.5716
39.3 acres/
20-100
Active Life of Facility
(yr)
38
20
20
30
==5=====
Thickness and
Permeability of Daily
Cover
>6 in./NI
>6in.
=i 1 x 10'5 cm/sec
i6 in.
i 1 x 10'5 cm/sec .
2:6 in.; NI
, i
Depth to Groundwater
(ft)
>30
>40"
>40"
160
=====
Average Permeability
of Soil or Hydraulic
Conductivity
Low; clay silt,
recompacted = 8 x 10'9
cm/sec
<1.6x 10'7 cm/sec
<1.6 x 10'7 cm/sec
Clay loam
M
Annual
Precipitation
Rate (in)
<25
NI
NI
NI
======
Annual
Evapotranspi-
ration Rate (in)
NI
NI
NI
NI
Models Used
NI
NI ! '
NI
NI
=====
Cost To
Prepare
Petition
NI
NI
NI
NI
Note:
Exemptions from groundwater monitoring requirements were granted during permit renewal processes. Therefore, it appears that it did not cost the landfill owner a separate amount to apply for a no-migration petition
The active life of a cell, one to two years, js estimated from information about the active life of the facility (12 years) and the total number of trenches (10) in the facility.
Grain size was analyzed; however, information was not provided.
40 acres indicate expansion of the landfill after closure of a 55-acre site.
47.5 tons per day were estimated, from the annual disposal rate, 12,350 tons per year (260 operating days per year).
Geolechnical investigation indicates that the geologic formations below the landfill cells are extremely impermeable and no known water-bearing formations exist to a reasonable depth below the landfill
Groundwater monitoring is not required, because there is no groundwater up to a depth of 130 feet.
The slate permit application review file indicates that the HELP model was used primarily for the waiver of the requirement for an engineering containment system.
273 tons per day were estimated from the estimated monthly diposal rate, 6,550 cubic yards per month, assuming 24 days (Monday through Saturday working days at the landfill) per month.
39 trenches are included for renewal for a four-year life span. Therefore, the life of each trench could be calculated by dividing four years by 39 trenches.
According to site-specific geology and poor water quality data, groundwater monitoring is not required. However, as an alternative, lysimeters have been installed at this site to measure fluid content of the substrata
The daily disposal rate was calculated from the annual disposal rate of 19,000 tons per year, assuming seven working days per week.
No groundwater was detected during the drilling operation. The depth to groundwater, 80 feet, was obtained from information about domestic wells from the state engineer's office.
The daily disposal rate was estimated from available data and the amount of waste received in 1990 (18,600 tons) as 700 tons per month to 1,650 Ions per month.
The expanded landfill occupies about 120 acres. However, renewal of the permit to operate 40 acres for four years was applied for.
The daily disposal rate was calculated from the annual disposal rate of 34,580 cubic yards per year, assuming seven working days per week (open Monday through Sunday).
38
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TABLE A-3: COMPARISON OF PARAMETERS AND VALUES USED BY EACH STATE
Name of Facility
Arizona*
Idaho
Montana
Nevada*
New Mexico*
Utah
Wyoming
KEY<" PARAMETERS AND RANGE VALUES
Size (acres) and Disposal
Rale (tons/day)
160; NI
16.5 to 370; 44.45
40lo<100;1.7to9
40; NI
480'(East phase: 200 acres);
350
80;20to25
2.5 to 139.6;
<1 to 273
Active Life of
Facility (yr)
30-40
>40lo>200
28 to 74
NI
20 (East phase)
20' to 200
4 to 50
Thickness and
Permeability of Daily
Cover
6 in; compacted cover
material
6 in; any soil type and fine
grained soil
6lol2in;NI
> 6 in; compacted cover
material
6in;NI
6 in; compacted cover
material and 3 x 10 3
cm/sec
120)
297.9 to >400
6.10 >350
>400
>430
35to>300
25 to 700
Average Permeability of
Soil or Hydraulic
Conductivity
Silly and gravelly sand;
1.23x10* sec* (sandy loam)
1.4 x I O-4 to 4.2 xlO-1 cm/sec
and clay w/high plasticity;
l.Ox 104 to 4.0x10-"
cm/sec
IxlO"1 to 9.6x10'" cm/sec
(vertical migration of gw:
0.2-2.3 fl/yr); IxlQ-4 to
8.1 IxlO-" cm/sec
1 xlO-" cm/sec (sill & clay)
and 1 x 10'3 - 1 x 10^ cm/sec
(fine sands); NI
1.0 x 10* cm/sec; NI
1.9x10* to 6xW cm/sec; NI
0.0038 to 9.4 x 10-8 cm/sec
Annual Precipi-
tation Rate (in)
10
6 to 10.21
9.53 to 14
4.1
9.56
6to>25
41013.86
Annual Evapolranspi-
ration Rate (in)
76
30 to 59.85
45 to 48
NI
93.95
60
5.583 to 54.5
Models Used
HELP, vcrs. 2.05.
WHPA, vurs. 2.0
(RESSQC)
HELP,
CHEMFLO,
MULTIMED 1
SUTRA
Not used
HELP II, vers. 2.5
HELP
HELP, WHPA
HELP
Cost To Prepare
Petition (S)
NI
4.IKlo5K"
25KI02-IOK
5io25K
NI
10K and public
hearing costs
18K
NI
Note:
"> The term "key" as used here reflects PRCs current best estimate of those items that may have been addressed by the stale in granting no-migration exemptions. The items were determined through review of facility documents and other
documents in the possession of the slate. The parameters shown in this table are subject to change after further analysis.
NI Information not included
* Only one facility has been approved for a no-migration petition at this time.
39
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-------
oEPA
United States
Environmental Protection Agency
(5305W)
Washington, DC 20460
Official Business
Penalty for Private Use
$300
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