BACKGROUND DOCUMENT
40 CFR Part 265, Subpart M
Interim Status Standards for
Land Treatment Facilities
Developed pursuant to Section 3004 of the
Resource Conservation and Recovery Act
U.S. Environmental Protection Agency
Office of Solid Waste
April 30, 1980
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TABLE OP CONTENTS
Page
I. Introduction 1
A. Purpose and Scope of the Land Treatment
Background Document 1
B. RCRA Mandate for the Regulation 2
C. Key Definitions 3
II. Need for Regulation 5
A. Description of the Land Treatment Process 5
B. Environmental Problems Associated with
Land Treatment 6
1. Surface Water Contamination 7
2. Air Emissions 7
3. Ground-Water Contamination 10
III. Synopsis of Proposed Land Treatment Standards
of December 12, 1978 11
IV. Comment Analysis and Rationale for the Final
Regulations 14
A. Changes in Terminology and Definitions 14
1. Changes in Terminology 14
2. Changes in Definitions 15
B. General Comments to the Proposed Land
Treatment Standards of December 18, 1978 21
1. Issue: Should land treatment be
allowed as a method to manage
hazardous waste? 21
2. Issue: Should land treatment of
highly toxic wastes or environ-
mentally persistent organics be
allowed? 23
3. The land treatment regulations are not
adequate with respect to monitoring and
testing protocols 25
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c.
4. Issue: Opposition to v.- ~i aces in
the standards .
5. Issue:
6. Issue
7. Issue
8. Issue
The regulations
on performance
ting and design
Crude oil shoul«
the land treatm<
The land treatm
are based largel
oily wastes, an<
priate for othe:
Preserving land
objective
it
1
it
it
aid be based
er than opera-
airements
Page
25
26
exempted from
regulations 27
regulations
a control of
e inappro-
stes
.s not an RCRA
9. Issue: Land treatment
be based on deg:
by the waste...
•.c Lations should
:e 3f hazard posed
Specific Comments to the Prc
Standards of December 18, 1<
1. Issue: Surface water ri
2. Issue: Waste analysis.
3. Issue: Growth of food-c
4. Issue: Soil monitoring
5. Issue: Recordkeeping ai
Issue: Closure
)C
'£
ad Land Treatment
ia n crops
29
31
32
33
33
39
40
64
6.
7. Issue: Prohibitions on :
and incompatible wastes
2 porting 84
86
table, reactive,
V. References
VI. Appendices
A. Interim Status Standards
B. Summary of Texas and Oklahor
[Treatment] Guidelines
97
102
.id Treatment
*
and Cultivation
ii
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I. INTRODUCTION
A. Purpose and Scope of the Land Treatment Background
Document
Pursuant to authorities in Subtitle C of the Resource
Conservation and Recovery Act of 1976, EPA has promulgated interim
status standards for treatment and disposal of hazardous waste in
land treatment facilities. This document provides the rationale
for the standards which have been established.
Draft regulations on this subject were proposed for
public comment on December 18, 1978 (43 FR 58946-59028). Numerous
comments on this proposal were received at public hearings and as
written responses. Synopses of the comments and the Agency respon-
ses to all of the comments received relative to the final interim
status standards for land treatment are addressed in Part IV of
this document.
This document is divided into four parts, followed by
references and appendices. Part I, Introduction, describes the
purpose and scope of this document, the legislative authority for
the regulations, and definitions used in their development. Part II,
Need for Regulation, explains the basic public health and the environ-
mental rationale supporting a need for regulation in this area.
Part III, Synopsis of the Proposed Regulation, summarizes the
regulation as proposed. Part IV, Comment Analysis and Regulation
Rationale, comprises the major portion of this document. It
presents the comments received on the proposed regulations and
the Agency's responses to those comments. These responses reflect
the rationale used in establishing the proposed standard and the
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final rationale for maintaining that standard or altering it in
view of the comments received or any new information which has
been obtained. It then presents the final regulatory language
resulting from this analysis.
B. RCRA Mandate for the Regulation
Section 3004 of Subtitle C of the Resource Conservation
and Recovery Act (RCRA) of 1976 (P.L. 94-580), requires the
Administrator of the Environmental Protection Agency to promulgate
regulations establishing standards, applicable to owners and
operators of hazardous waste treatment, storage, and disposal
facilities, as may be necessary to protect human health and the
environment. Section 3004 further requires that these standards
are to include, but need not be limited to, requirements respect-
ing: (1) location, design, construction, and operation of such
facilities; (2) treatment, storage, or disposal of all hazardous
waste received pursuant to such operating methods, techniques,
and practices as may be satisfactory to the Administrator; and
(3) maintenance of records of hazardous wastes treated, stored,
or disposed, along with satisfactory reporting, monitoring, and
inspection. Land treatment facilities used for the treatment or
disposal of hazardous wastes are covered by this mandate.
Subtitle C of the Act, specifically §3005(e), also
provides for a period of interim status to owners and operators
of existing facilities for treatment, storage, and disposal of
hazardous wastes. Interim status applies to that period between
the effective date of the Section 3004 treatment, storage, and
disposal regulations and the date on which a permit is issued
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pursuant to Section 3005 of the Act. Section 3005 provides that
after the effective date of the regulations, treatment, storage,
and disposal shall not be carried out except in accordance with a
permit issued pursuant to Section 3005. However, it also estab-
lishes that persons who have applied for a permit, but whose
applications have not been acted on by the time the regulations
become effective, shall be granted interim status.
A complete rationale for establishing interim status
standards and responses to the public comments on that subject are
presented in the background document entitled "General Issues
Regarding Interim Status Standards."
This background document on interim status standards
i
for land treatment addresses the standards applicable to land
treatment facilities during the time a facility is granted interim
status.
C. Key Definitions
The following are key definitions pertinent to the
standards applicable to land treatment facilities. Definitions
that have changed as a result of public comment or internal Agency
decisions are footnoted and the rationale for the changes are
referenced.
"Active portion"* means that portion of a facility
where treatment, storage, or disposal operations are being or
have been conducted after the effective date of Part 261 of this
Chapter and which is not a closed portion. (See also "Closed
Portion" and "Inactive Portion.")
* Revised definition, see background document on definitions.
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"Constituent" or "hazardous waste constituent" means a
constituent which caused the Administrator to list the hazardous
waste in Part 261, Subpart D, of this Chapter, or a constituent
listed in Table 1 of 261.24 of this Chapter.
"Food-chain crops" means tobacco, crops grown for human
consumption, and crops grown for feed for animals whose products
are consumed by humans.
"Ground water" means water below the land surface in a
zone of saturation.
"Hazardous waste" means a hazardous waste as defined in
§261.3 of this Chapter.
"Incompatible wastes"* means a hazardous waste which is
i
unsuitable for:
(i) Placement in a particular device or facility
i
because it may cause corrosion or decay of
contaminant materials (e.g., container,
inner liners, or tank walls); or
(ii) Commingling with another waste or material
under uncontrolled conditions because the
commingling might produce heat or pressure,
fire or explosion, violent reaction, toxic
dusts, mists, fumes, or gases, or flammable
fumes or gases.
(See Part 265, Appendix IV, of th%s Chapter for
examples.)
* Revised definition, see background document on definitions
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"Land treatment facility"''' means a facility or part of
a facility at which hazardous waste is applied onto or incorporated
into the soil surface; such facilities are disposal facilities if
the waste will remain after closure.
"Run-off" means any rainwater, leachate, or other liquid
that drains over land from any part of a facility.
"Run-on" means any rainwater, leachate, or other liquid
that drains over land onto any part of a facility.
"Unsaturated zone" or the "zone of aeration" means the
zone between the land surface and the water table.
II. NEED FOR REGULATION
A. How Land Treatment Achieves Environmental Control
Land treatment is a waste management practice that
involves application of waste onto the soil and/or incorporation
of the waste into the soil, usually in thin layers or applications.
Land treatment facilities frequently utilize common farm practices
such as tilling, contouring, and erosion control techniques. Farm
equipment is often used to plow or disk the waste into the soil,
and nitrogen and phosphorus fertilizers are often added to enhance
microbial degradation of the waste.
The soil in a land treatment facility functions as both
a biological treatment medium and a physical-chemical filter
medium. The efficacy of the soil as a waste treatment medium
depends upon maintaining conditions that promote and enhance the
t Formerly "landfarm," revised definition, see discussion in
Part IV(A)(1) of this document.
New definition, see background document on definitions.
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survival of soil microorganisms. In addition, certain physical
parameters of the soil must be maintained in order to maximize
the physical-chemical immobilization of inorganic waste
constituents.
Theoretically, the soil has unlimited capacity to
biodegrade nonpersistent organic waste constituents as long as
acceptable conditions are maintained. In contrast, the capacity
of the soil to physically-chemically filter and immobilize inor-
ganic and persistent organic waste constituents, even with careful
management, is finite. Ultimately, any soil used as a chemical-
filter medium will become saturated with nondegradable waste
»
constituents. Such a dynamic treatment system requires careful
management during operation, as well as long-term monitoring and
maintenance if contaminants are to be prevented from migrating to
surface or ground water. If appropriate operating and design
parameters are followed, land treatment can be an environmentally
acceptable method for treating certain types of hazardous wastes.
B. Potential and Actual Environmental Damages
Land treatment of hazardous waste is a relatively new
waste management practice and is not in widespread usage. Knowl-
edge about conditions necessary to promote biodegradation of
wastes and knowledge about soil attenuation capacities is still
being developed as practical experience is gained in sfche field.
Information on long-term effects of land treatment is virtually
nonexistent. EPA is not aware of any studies of land treatment
facilities which have been completed and closed. At currently
operating land treatment facilities, environmental monitoring
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has often been absent, inadequate, or inappropriate.
Recent State requirements frequently stress groundwater
monitoring and rarely include unsaturated zone monitoring (i.e.,
soil and soil-pore water monitoring). The consequence of using
groundwater as the sole measure of environmental performance is
that contamination will not be detected until it reaches ground
water. Remedial measures to prevent further contamination of the
ground water, once contamination has been detected, would be
extremely difficult.
The absence of air emission monitoring requirements for
hazardous waste land treatment facilities has been documented by
a recent study.1 According to the recent study, there is no
specific mention of protection of air resources at land treatment
facilities in any State regulation. The study concludes that
there is a strong need for national regulations which recognize
the potential for air pollution from land treatment.
Because of the lack of long-term experience, the limited
use of land treatment as a waste management practice, and the
lack of appropriate environmental monitoring, there is very little
information on actual public health and environmental impacts of
land treatment. Although mechanisms for contamination of the
surface water, air, and ground water clearly exist, there are few
documented damage cases involving hazardous waste land treatment.
The following is a discussion of the actual and potential avenues
of contamination and documented damage incidents that have been
associated with hazardous waste land treatment.
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1. Surface Water Contamination
Surface water situated near a land treatment site
may be subject to pollution from contaminated run-off resulting
from erosion of the soil-medium or dissolution of wastes from the
active portions (i.e., areas to which waste has been applied).
Because the process of land treatment introduces and concentrates
wastes in the soil surface, run-off water may be contaminated to
the extent that it will impact certain trophic levels in the
aquatic ecosystem. 2.
One of the few damage incidents reported in the
literature involved the erosion of contaminated soil from a land
treatment facility as a result of a rainstorm occurring soon after
an oily sludge was applied. Erosion of the soil-waste medium by
run-off carried contaminants to an onsite lake, resulting in a
fish kill.3
2. Air Emissions
A recent EPA study that evaluated emission control
criteria for hazardous waste management facilities describes one
air-related damage incident resulting from land treatment of oil
refinery waste.^ In this case, neighbors complained of odors and
there were some reports of damage to paint on nearby houses.
Although there are few documented cases of air
pollution from land treatment, the potential for release of
significant quantities of pollutants to the atmosphere exists.
The disposal of oily-type wastes provides an excellent example of
air pollution potential. Gases and odors generated increase
initially during spreading operations and subside as microbial
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decomposition occurs. However, in the weathering (spreading)
method of disposing of leaded gasoline storage tank wastes, the
vapors can be inhaled or absorbed through the skin. At the levels
of organically-bound lead (20 to 200 ppm) encountered in the
storage tank sludge, a potential lead-in-air hazard could occur
during the weathering process.4
Since many of the oily wastes have a high water
content, they are commonly applied to the land by spraying. This
would allow for aerosol formation and release of waste constitu-
ents. In addition, air pollution can occur through direct vola-
tilization of constituents contained in the waste after it has
been spread on the land. Again, because of the high water content
of many oily-type wastes, initial disposal often involves allowing
the water to evaporate from the waste prior to mixing with the
soil. During this period of time, all constituents of equal or
higher volatility than water will be released to the atmosphere,
and other waste constituents will also evolve due to co-solvent
processes.1
A third mechanism for air pollution is by entrainment
of particulates through wind erosion. This latter mechanism may
become increasingly important throughout the life of an active
land treatment site. Since most oily wastes contain trace elements,
these tend to accumulate in the soil with each additional applica-
tion of waste material. The initial particles released to the
atmosphere through wind erosion for a new site will contain low
concentrations of trace elements; however, several years after a
site has been in operation, the concentration of trace elements in
soil particles will be much higher-^
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In addition to the potential for creating localized
concentrations of air pollutants which are potentially hazardous
to health, there is a real potential for significantly reducing
air quality through photochemical reactions of constituents
evolving from the disposal site. This may be of particular
concern in areas where ambient concentrations of photochemical
oxidents are already high, such as in parts of California.1
3. Ground-Water Contamination
The land treatment of non-hazardous waste has
resulted in contamination of ground water by nitrates and phosphates
which were present in the waste or added as fertilizer.5 Hazardous
waste land treatment has the same potential consequences, though
EPA is not aware of any documented ground-water contamination
incidents resulting from the practice. This lack of documentation
should not be interpreted to mean that hazardous waste land treat-
ment poses no threat to the ground water. The potential for con-
tamination may be greater for hazardous than nonhazardous wastewater
and sludge, because the contaminants are often present at greater
concentrations.2
The paucity of data available on land treatment-
related ground-water cases may be a result of inadequate monitoring
and the time required for problems to manifest themselves.
In light of the many avenues for environmental
damage from land treatment, the Agency strongly believes that regu-
lation of this,practice is necessary. A land treatment facility
is a dynamic treatment system requiring careful operation and
long-term monitoring and maintenance. Without proper regulatory
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control, land treatment can cause significant environmental
damages.
III. SYNOPSIS OF THE PROPOSED REGULATIONS
The regulations proposesd on December 18, 1978, included
certain standards applicable specifically to land treatment
facilities (§250.45-5) and standards relevant to all facilities
(§250.42, 250.43, and 250.45). Those portions of the above
standards applicable during interim status were proposed in
§250.40(c)(2).
The full set of proposed land treatment regulations (§250.45-5)
addressed the following:
0 restrictions on land treatment of ignitable, reactive,
volatile, and incompatible waste
0 restriction against contact of a land treatment facility
with navigable water
0 restrictions against location of the treated area within
five feet of the high water table or within 500 feet of
a public or private water supply
0 specifications regarding the soil types acceptable for
a land treatment facility
0 minimization of erosion, landslides, and slumping,
including a maximum slope of five percent
0 sealing -of caves and wells connected to the subsurface
environment within a land treatment facility
0 maintenance of a soil pH of at least 6.5
0 restriction on the zone of incorporation from becoming
anaerobic
0 restrictions on waste application when the soil is
saturated with water or when the soil temperature is
below 0°C
0 restriction on application rates of phosphorus and
nitrogen
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soil monitoring/ including determination of background
conditions at three times the zone of incorporation,
periodic sampling at that depth to determine if back-
ground levels have been exceeded, corrective action if
a significant increase over background has occurred.
0 restriction on the growth of food-chain crops on the
treated area of a land treatment facility.
0 requirement that at closure, the soil of a land treatment
facility, if it meets the characteristics of a hazardous
waste, be removed and managed as a hazardous waste. A
variance to this requirement provided that the land treat-
ment facility could be closed in accordance with landfill
closure requirements if the owner or operator could demon-
strate to the Regional Administrator that long-term
environmental protection equivalent to a landfill could
be achieved.
The interim status standards specific to land treatment,
proposed in §250.40(c)(2)(XV) of the December 18, 1978, regulations,
included only requirements for closure. The application of the clo-
sure requirements also included by reference, the soil monitoring
requirements of the full set of proposed land treatment regulations.
Thus, the proposed interim status standards required that:
0 background soil conditions of the land treatment facil-
ity be determined by soil analysis in the zone of
incorporation (new facility) or in similar local soils
(existing facility).
0 at closure, if the soil of a land treatment facility
meets the characteristics of a hazardous waste, it
either must be returned to its preexisting (background)
condition, or must be removed and managed as a hazardous
waste. A variance to this requirement provided that
the land treatment facility could be closed in accordance
with landfill closure requirements if the owner or
operator could demonstrate to the Regional Administrator
that long-term environmental protection equivalent to
that for a landfill could be achieved. ^
Additional interim status standards were proposed which were
applicable to all facilities. Waste analysis and recordkeeping
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and reporting requirements are included in this category. As
proposed, these interim status requirements included:
0 waste analysis to determine the hazardous constituents
and properties of the waste prior to initial disposal.
0 verification of certain properties of each shipment of
waste received; and periodic, comprehensive analysis of
waste if there were indications of changes in composition.
0 recordkeeping and reporting, including an operating
log, a record of the quantity and description of each
waste handled at the facility, locations where each
waste is treated or disposed and the method and dates
of treatment or disposal, the results of the waste
analysis performed, monitoring data, reports of visual
inspections, and records of incidents requiring initia-
tion of a contingency plan.
Portions of the proposed waste analysis and recordkeeping
regulations, including revisions in responses to the comments,
are included in the general facility requirements of the interim
status regulations and discussed in the background documents
dealing with waste analysis and with manifest, recordkeeping, and
reporting. The rationale for those portions which have not been
included in the land treatment interim status standards are dealt
with in this document.
Although not proposed as interim status standards, the Agency
has decided to include other portions of the full set of proposed
standards in the interim status regulations because they serve
important environmental objectives, and generally meet the criteria
for inclusion in interim status. The Agency feels that these
requirements conform to the criteria described in the background
document entitled "General Issues Regarding Interim Standards" for
in inclusion in interim status standards. These additional requirements
include:
0 control of run-on and run-off to active portions of the
facility
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0 restrictions on land treatment of ignitable, reactive,
and incompatible wastes.
restriction on the growth of food-chain crops on the
treated area of a land treatment facility
Comments received relevant to the above requirements are
addressed in the next section of this document.
IV. COMMENT ANALYSIS AND REGULATORY RATIONALE
A. Changes in Terminology/Definitions
1. Changes in Terminology
The Agency has decided to use the term "land
treatment facility" in place of "landfarm." Although no public
comments were received suggesting a change in terminology/ the
Agency felt it was desirable to use a term which more accurately
describes the purpose of this particular waste management practice,
The terms "landfarm" and "landfarming" misleadingly imply a connec-
>
tion between hazardous waste disposal and crop production or soil
beneficiation. The term "land treatment," in contrast, implies
that the land or soil is used as a medium to treat hazardous
waste. This meaning, which is now reflected in the regulations,
is consistent with the Agency's philosophy that the application
of hazardous waste to the soil is a waste management practice
reserved for those waste streams that are treatable in a soil
system. Any benefit derived from land treating hazardous waste,
beyond that of treatment, is incidental and is not considered an
appropriate justification for allowing the practice.^ Treatment,
in the context it is used here, means a reduction in the hazard
posed by the waste. This reduction occurs as a result of altera-
tions in the chemical state of the waste via biological and
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chemical interactions occurring in, and enhanced by the soil.
The Agency acknowledges that the soil has the
capacity to filter and dilute waste. However, these physical
mechanisms provide little or no net reduction in hazard if they
do not alter the chemical state of the waste. Consequently, the
use of the soil solely as a filtration or dilution medium is not
considered appropriate for land treatment.
2. Changes in Definitions
The Agency proposed a number of definitions, unique
to land treatment, in the December 18, 1978, regulations. As a
result of comments received and changes made to the proposed
regulations, some of these definitions have changed or have been
deleted. Below is a discussion and rationale for any changes
that were made.
a. "Attenuation"
(i) Proposed definition
"Attenuation means any decrease in the
maximum concentration or total quantity of
an applied chemical or biological constituent
in a fixed time or distance traveled resulting
from a physical, chemical, and/or biological
reaction or transformation occurring in the
zone of aeration or zone of saturation.
(ii) Change made
"Attenuation" has been deleted from the ISS
definitions.
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(iii) Rationale for change
The regulation containing the term "attenuation"
is not part of the interim status land treat-
ment regulations.
b. "Fertilizer"
(i) Proposed definition
"Fertilizer" means any substance containing
one or more recognized plant nutrient(s)
which is used for its plant nutrient content,
and which is designed for use or claimed to
have value in promoting plant growth.
(ii) Change made
"Fertilizer" has been deleted from the ISS
definitions.
(iii) Rationale for change
"Fertilizer" was not used in the proposed
regulations but it did appear in the background
document on landfarming. The Agency has
decided to define only those terms needing
definition, that appear in a regulation. It
was therefore an oversight to identify "fertil-
izer" in the proposed regulations.
c. "Landfarming of a Waste"
(i) Proposed definition
11 Landf arming of a waste" means application of
waste onto land and/or incorporation into the
surface soil/ including the use of such waste
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as a fertilizer or soil conditioner. Synonyms
include land application, land cultivation,
land irrigation, land spreading, soil farming,
and soil incorporation.
(ii) Change made
The terminology and definition have been
revised. The revision is as follows: "Land
treatment facility" means a facility or part
of a facility at which hazardous waste is
applied onto or incorporated into the soil sur-
face; such facilities are disposal facilities
if the waste will remain after closure.
(iii) Rationale for change
The Agency, besides changing the terminology
from landfarming to land treatment, has de-
cided to revise the definition of land treat-
ment so that it is the facility, as well as
the practice occurring at that facility,
that is defined. As previously discussed,
the Agency feels that the new terminology and
revised definition more accurately describe
the purpose of this particular waste management
practice. The term "landfarming" misleadingly
implies a connection between hazardous waste
disposal and crop production or soil benefi-
ciation . The term "land treatment" in con-
trast implies that the land or soil is used
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as a medium to treat hazardous waste. Any
benefit derived from land treating hazardous
waste, beyond that of treatment, is incidental
and is not considered an appropriate justifi-
cation for allowing the practice.
Treatment, as it applies to land treatment,
is considered to be a reduction in the hazard
posed by the waste as a result of biological
and/or physical-chemical soil-waste interactions.
This interpretation of treatment is intended
to promote the concept that land treatment is
a waste management practice reserved for waste
streams which are not treatable in a soil sys-
tem. The application of waste streams which
are not treatable in the soil can only aggravate
the hazard posed by the waste.
The synonyms included in the proposed
definition have been dropped. The Agency
feels that each of these terms may have common
uses or connotations which are different from
the definition of land treatment and, thus,
should not be used as synonyms.
The Agency has added a clause to the
definition which defines land treatment
facilities as disposal facilities if the
waste applied to the site remains after
closure. This addition is necessary because
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land treatment facilities involve both treat-
ment and disposal. The Agency considers the
practice to be predominantly treatment but
realizes that certain waste constituents
(e.g., heavy metals), even if they are in low
concentrations in the waste, will accumulate
in the soil.
d. "Soil conditioner"
(i) Proposed definition
"Soil conditioner" means any substance added
to the soil for the purpose of improving the
soils physical properties by increasing water
content, increasing water retention, enhancing
aggregation, increasing soil aeration, improv-
ing permeability, increasing infiltration, or
reducing surface crusting.
(ii) Change made
"Soil conditioner" has been deleted from the
ISS definitions.
(iii) Rationale for change
The rationale for deleting "soil conditioner"
from the definitions is the same as for
"fertilizer."
E. "Treated Area of a Landfarm"
(i) Proposed definition
"Treated Area of a Landfarm" means that por-
tion of a landfarm that has had hazardous
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waste applied to it,, to include the zone of
incorporation.
(ii) Change made
"Treated Areas of a Landfarm" has been deleted
from the ISS definitions.
(iii) Rationale for change
The term "Treated Area of a Landfarm" has
been replaced with the term "Active Portion."
"Active Portion" means that portion of a
facility where treatment, storage, or disposal
operations are being or have been conducted
after the effective date of Part 261 of this
Chapter and which is not a closed portion.
The Agency has chosen to use active
portion in place of treated area because the
use of the former for all facilities makes
use of the latter unnecessary. Additionally,
the definition of active portion specifically
defines, in a temporal sense, those parts of
the facility which are subject to Subtitle C
regulation.
F. "Zone of Incorporation"
(i) Proposed definition
"Zone of Incorporation" means the depth to
which the soil on a landfarm is plowed or
tilled to receive waste.
(ii) Change made
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"Zone of incorporation" has been deleted from
the ISS definitions.
(iii) Rationale for change
Due to changes made to the soil monitoring
regulations, "zone of incorporation" is no
longer used.
B. General Comments Relevant to the Interim Status Standards
Some comments were received that relate to the land
treatment regulation as a whole, rather than to a particular
standard. These comments are addressed below, followed by comments
on specific parts of the regulation.
1. Issue; Should land treatment be allowed as a
method to manage hazardous waste?
Comment was received that the proposed EPA
regulations would not protect public health and the environment
nor prevent destruction of valuable land, and that no modifica-
tion to the regulations could be envisioned which would make land
treatment acceptable. No reasons were given for this position.
Response; The literature on land treatment reveals
that a properly operated land treatment facility can provide environ-
mentally sound disposal through the physical, chemical, and biolog-
ical interaction of the soil and the waste.2»6/7,8,9 These inter-
actions result in degradation of organic wastes and immobilization
of metallic contaminants through physical-chemical interactions
with the soil.
The discussion of soil monitoring, later in this
section, describes evidence that shows that in a properly designed
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and operated land treatment facility, migration of waste contaminants
beyond the depth to which the waste is incorporated into the soil
should be minimal.
EPA recognizes, as was discussed in Part II of
this document, that land treatment relies less on physical contain-
ment than other disposal methods. Also, the concept of spreading
hazardous waste on the land may offer more opportunity for wastes
to enter the environment than other land disposal options.
EPA has addressed these issues by promulgating
performance oriented monitoring requirements that will quickly
indicate any failure of the land treatment facility to perform in
an environmentally sound manner. This is the basis of the unsat-
urated zone monitoring requirements of the interim status regula-
tion. The unsaturated zone monitoring requirements will allow
the owner or operator, or the Regional Administrator to quickly
identify any waste migration that would post a potential threat
to public health and the environment through ground-water
contamination.
The interim status regulations also include
standards to prevent surface water contamination and specify
certain operating and design and closure requirements to ensure
that facility operation will not contaminate ground water or
surface water or otherwise threaten public health. The Agency is
confident that these regulations, having undergone*a thorough
public and Agency review, will be fully protective of public
health and the environment.
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2. Issue: Should land treatment of highly toxic
wastes or environmentally persistent, organics be allowed?
The preamble to the proposed regulations suggested
that environmentally persistent organics should not be land
treated in concentrations that would result in accumulation of
these organics in the soil. The practice was not banned because
of the difficulty in defining "environmentally persistent organics,"
Comment was requested on how this characteristic might be defined
generically, and whether the burden should be shifted to the
owner or operator to show than an organic applied in a certain
concentration will be degraded within a certain amount of time.
Conunenters made the following points about this
issue:
0 Prior to land treatment of persistent organics, owners
or operators using land treatment should be required to
show that the half-life of persistent organics be one
year or less before land treatment is allowed.
0 A definition of persistent organics should be included
as part of the regulations under Section 3001 of the
Act.
0 The burden of proof that such materials are amenable to
microbial action in soil should be on the owner or operator.
0 There should be no prohibition on environmentally persis-
tent organics, since the closure requirements of the
regulations (removal of contaminated soil from the land
treatment facility) and soil monitoring will sufficiently
discourage their land treatment.
23
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0 Environmentally persistent organics should not be land
treated because within days or weeks after application,
these toxins could begin entering the environment
through erosion.
0 The definition of environmentally persistent organics
should include a half-life related to the time the
wastes are incorporated into the land (e.g., 50% of
the waste must degrade within one year from the date
it is applied).
0 Land treatment of materials which are banned from use,
because they are considered dangerous in even minute
quantities, should be disallowed in a land treatment
facility. The potential for dispersion of such materials
by wind and surface water run-off is a major concern. If
such materials are land treated, massive environmental and
public protest will ensue in light of "LD-50 values of
pesticides on fish and their penchant for bioaccumulation."
Response; It is evident from the above comments on
environmentally persistent organics that there was no clear public
concensus on this issue. Given the diversity of these comments
and the fact that the Agency does not feel that it has sufficient
information at this time to establish any prohibitions on land
treatment of environmentally persistent wastes, the interim status
standards do not address those wastes. Similarly, the Agency lacks
sufficient information at this time to support restrictions for
land treatment of "highly toxic wastes."
24
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However, the Agency believes that it is important
to further investigate the land treatment of environmentally per-
sistent and highly toxic wastes to determine if special restric-
tions should be applied. The Agency plans to deal with this issue
in future regulations on land treatment.
3. Issue; The land treatment regulations are not
adequate with respect to monitoring and testing protocols
A commenter pointed out that because of potential
dangers associated with landspreading of sewage sludge and other
wastes, EPA should adopt stronger monitoring and testing protocols.
Response: The commenter did not suggest alternative
monitoring and testing (presumably waste testing) procedures, nor
were reasons given that the proposed procedures did not appear to
be adequate. There was no elaboration on the "potential" dangers
referenced. Specific comments received on the proposed soil
monitoring procedures and responses to them are presented later
in this section. Comments on general waste analysis procedures
are presented in the background document dealing with that subject.
4. Issue; Opposition to variances in the standards
A discussion of waste analysis requirements specific to land
treatment is discussed later in this document in Part IV(c)(2).
A commenter suggested that the variances in the proposed land
treatment regulations provided too little control and would result
in potential danger to ground water and surface water.
Response; The commenter did not indicate
specific variances of concern or the reasons that damages might
result.
25
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The interim status standards generally do not
include regulations containing variances because they require
interaction with the Agency as a part of the permitting process.
5. Issue; The regulations should be based on
performance requirements rather than operating and design requirements
A commenter pointed out that the technology
of land application of complex organic wastes is in its infancy
and advances in knowledge are being made rapidly. Therefore,
operational standards will limit potential for innovation and
advances. It was suggested that performance can adequately be
measured by -monitoring of soil, ground water, and surface water.
The commenter also suggested that although variances are provided
in the regulations, it is doubtful that they would actually be
granted by the permitting authority-
Response; A number of comments were received on
the subject of performance standards versus operating standards.
These comments related to all parts of the proposed regulation,
including the comment above on land treatment. Under RCRA, EPA
is authorized to set both performance and operational standards,
depending on the applicability of either approach to the environ-
mental problem being addressed by the regulations.
The Agency believes that pure performance
standards for land treatment can result in failure*to adequately
protect the environment. For example, the standard might require
only that the ground water be monitored to ensure no degradation
beyond the primary drinking water standards. One failure of this
approach would be that numerous organic and some metallic substances
26
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are placed in land treatment facilities which are not covered at
this time by the drinking water standards, but which may cause
damage to public health. A second failure is that by the time
ground-water contamination is detected in a land treatment
facility, the entire soil profile would be contaminated, making
removal action difficult and expensive.
However, other performance measures can be
constructively employed. The Agency believes that the regulations
should use such performance standards where feasible in an effort
to provide maximum flexibility to owners or operators. As the com-
menter suggested, the technology of land treatment is still in an
early stage of development, and flexibility in the standards is
desirable as long as environmental protection can be maintained.
The changes to the land treatment regulations
made as a result of this and other comments reflect increased
flexibility. This is particularly true in the key areas of food-
chain crops, monitoring, and closure.
6. Issue: Crude oil should be exempted from the
land treatment regulations
A commenter suggested that crude oil does not
contain concentrations of metals normally found in other waste
oils that have been refined or used in industrial processes. The
commenter stated that crude oil properly applied adds nutrient to
the soil, and that the Bureau of Land Management uses oil field
wastes to aid in restoration of rights-of-way.
Response; EPA has no data to substantiate that
waste crude oil, which is hazardous under Subpart C of Part 261
27
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can be applied to the land without impacts on the environment.
The commenter provided no data or references to substantiate the
claims in the comment, except the general reference to the Bureau
of Land Management.
The Agency contacted the Bureau of Land
Management, Division of Right-of-Way, and learned that they had
no knowledge of such an activity within BLM.10 The BLM regional
office dealing with oil and gas surface protection indicated that
in some areas, BLM has "recommended" spraying an oil film on
sandy areas to prevent blowing of sand. However, pure crude oil,
not waste oils, were recommended for this technique. H It was
also indicated by another BLM regional office that waste oils are
commonly used for road oiling to reduce dust.12
The above very limited practices are not
considered land treatment of waste oils from oil production
operations as defined previously since dust control, not waste
treatment, is the concern. Unless an area is designated as a
hazardous waste land treatment facility, it may not be used for
oils classified as hazardous. Furthermore, the Agency believes
that the significant issue is not whether waste crude oil has
lower concentrations of metals than other waste oils, but whether
there is documented evidence that application of that waste, or
f
any waste which fails the test for hazardousness under Part 261
of the regulations, causes no contamination of ground water or
surface water when placed in a land treatment facility. Although
waste crude oil usually contains lower concentrations of heavy
metals than do other waste oils, a combination of high application
28
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rates and multiple applications can cause a significant buildup
of heavy metals in the soil. Thus, the Agency does not concur
with the recommendations of the commenter-
7. Issue; The land treatment regulations are
based largely on control of oil wastes, and are inappropriate for
other wastes
A commenter stated that EPA's regulations are
based on Texas' and Oklahoma's land treatment regulations, which
emphasize regulation of oily waste and are, therefore, not
applicable to other industrial sludges which may be no more harm-
ful than POTW sludges. The regulations should be revised to
consider persistence of contaminants and their availability for
crop uptake, and the effect of proper crop management on the
leaching potential of contaminants. Iowa's rules on municipal
sludge disposal should be used as a model.
Response; EPA's land treatment regulations were
developed for all types of hazardous wastes and are not designed
around State standards for oily waste. State guidelines of Texas
and Oklahoma (see Appendix I) did provide an important data base
for the national regulations because of the experience of those
States in regulating land treatment facilities. However, the
final Federal interim status standards differ substantially from
the regulations of either of these States. Furthermore, the
Texas guidelines are applicable to all types of industrial waste-
waters and sludges, not just oily wastes. EPA also had as an
information base for these regulations numerous studies, listed
in the references, and the recently promulgated regulations under
29
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Section 4004 of RCRA for landspreading of non-hazardous wastes,
including POTW sludge. The background documents, and associated
references for the Section 4004 regulations also provide a basis
for these regulations.
The Agency does not consider the Iowa
regulations for POTW sludge to be totally appropriate for land
treatment of hazardous waste. However, the Agency has incorporated
into the "Food-Chain Crops" Section of the interim status regulation
specific standards for cadmium. While these standards are not
identical to the Iowa standards, there is similarity in that they
both prescribe a specific loading rate. Iowa's approach controls
the amount of waste that can be applied based on the concentration
of specific constituents, while the Agency's approach limits only
the amount of cadmium that can be applied and not the waste.
The Agency was able to develop specific
standards for cadmium because of the significant amount of field
experience and research that'has been done in this area. This is
not the case with other constituents covered by the land treatment
regulations under Subtitle C of RCRA. Information is very limited
on factors such as attenuation of various substances in the soil
and uptake in plants. Without such information, the regulations
cannot be tailored to such factors as persistence of contaminants,
availability for crop uptake, effect of proper crop management,
etc. Hopefully, the Agency will be able to revise the regulations
in this direction over time as more information is gained from
the regulated community and various research studies on the per-
formance of land treatment facilities.
30
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Additional considerations of the Agency
regarding crop growth on land treatment facilities are discussed
in the comments on food-chain crops later in this section.
8. Issue; Preserving land is not an RCRA objective
Commenting on the discussion in the preamble to
the December 18, 1978, proposed regulations, a commenter noted
that a stated objective of the regulations, preventing conversion
of huge tracts of productive land to land with limited potential
for productive use, was not a reasonable Federal objective under
RCRA. Also noted was that the amounts of land involved to date
are not "huge" compared to other types of land use, such as
housing, wilderness areas, and industrial sites.
Response: This issue relates primarily to the
requirements for closure, which are discussed later in this
section. EPA would agree that the adjective "huge" overstates
the amount of land currently involved in land treatment. How-
ever, the practice could grow substantially as a waste management
practice, depending on its relative costs compared with other
treatment and disposal practices. The Agency believes that it is
in the best interests of the nation, and within the Congressional
intent that, in development of land disposal practices under
RCRA, considerations be given to the impact of those practices on
future land use. Also, it would be narrow-sighted and counter-
productive to ignore broad Congressional and administration
priorities in developing regulations under a particular law.
These regulations, however, do not restrict the amount of land
which can be used as land treatment facilities, nor are they
31
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specifically aimed at controlling land use per se. The Agency is
establishing requirements in the land treatment Subpart to assure
that the land treatment objective is accomplished, to protect
various environmental media (surface water, air, and ground water),
and to protect food-chain crops. Land use may be affected by
regulations designed to protect public health and the environment.
9. Issue; Land treatment regulations should be based
on the degree of hazard posed by the waste
A commenter stated that some hazardous waste can
be land treated safely and with beneficial effects to the soil
and crops, while other hazardous waste (highly toxic, nonbiode-
gradable) should not be land treated. Therefore, not all criteria
for determining "hazardous waste" for land treatment should be
weighed equally.
Response: The commenter offered no examples or
specific suggestions relative to the general comment. There
were also no data or references provided. Thus, the response
must also be relatively general.
Ideally, the Agency would be able to develop a set
of detailed, tailored standards for land treatment of various
wastes, including acceptable levels of various contaminants in
the soil and in crops. Unfortunately, the state-of-the-art of
land treatment will not support such regulations. Information is
.>
generally not available to "fine tune" the system as proposed.
(This is discussed in more detail in response to comments regarding
growth of food-chain crops.)
Some waste-class distinctions have been made in
32
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the regulations, such as the restrictions on ignitable, reactive,
and incompatible wastes.
C. Specific Comments to the Proposed Land Treatment
Standards of December 12, 1978
1. Issue; Surface water run-off
a. Proposed regulation
Prior to beginning this discussion it is
necessary to briefly describe the new terminology that will be
used. The Agency believes that the term "run-off" as used in the
proposed regulation concerning the construction of "diversion
structures to divert all surface water run-off from the active
portions of a facility" was confusing. Therefore the term "run-
on" has replaced the term "run-off" in these situations. That
is, as used in these regulations, run-on is water which runs onto
the active portions of a land treatment facility or landfill from
other portions of the facility or from outside of the facility -
Run-off is rainwater, leachate, or other liquid which flows from
the active portions of a disposal facility.
Requirements for -control of surface water run-
off and run-on were not included in the proposed interim status
standards for land treatment facilities. However, those require-
ments were specified in the proposed full set of standards in
§250.43(b) and (c) . These regulations required the owner or
operator to construct diversion structures capable of preventing
run-on from entering a land treatment facility. A variance to
this requirement was allowed where an owner or operator could
demonstrate to the Regional Amdinistrator than run-on would not
33
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enter the site and come in contact with the hazardous waste. The
proposed regulations also required the owner or operator to
collect and confine run-off from active portions of the facility
to a point source before discharge or treatment.
B. Comments to the Proposed Regulation
The background document for Interim Status Standards for
Landfills discusses the proposed General Facilities Standards con-
cerned with discharges from hazardous waste facilities (§250.43(a)),
diversion structures for control of run-on (§250.43(b)), and
control of run-off from active portions (§250.43(c)).
C. Response to Comments
A discussion of the comments received on the proposed
run-on and run-off requirements is presented in the background
document on landfills.
In these interim status regulations land treatment
facilities will be subject to the same requirements as landfills
regarding surface run-on and run-off. Run-on must be diverted
away from the active portions of the land treatment facility.
Run-off from the active portions must be collected. If the
collected run-off is a hazardous waste it must be managed as a
hazardous waste. If it is not a hazardous waste it may still
need to be analyzed, treated, or otherwise managed to comply with
Subtitle D of RCRA or the Clean Water Act. *
EPA believes that run-on and run-off controls are
necessary at land treatment facilities because this disposal
option involves the placement of hazardous waste on or just
beneath the soil surface. Because the waste is exposed during
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the application and incorporation process, the potential for loss
via surface water erosion is initially high. During site operation,
the potential for run-off to become contaminated is directly
related to the frequency and rate of waste application. In the
long term, the potential for contaminating run-off is further
increased as refractory waste contaminants become concentrated
in the surface soil.
The release of dissolved or suspended waste contaminants
or contaminated sediment from a land treatment facility can have
severe ecological consequences. One damage case, involving con-
tamination of a lake by run-off from an oily waste land treatment
facility, has already been documented.^ At another oily waste
land treatment site in Texas, surface run-off from experimental
plots were found to contain 30-100 mg/1 of oil.^ The study
concluded that "oil and nutrient contents of the rainfall run-off
water from the soil cultivation Cland treatment] process can be
relatively high, and this discharge water should receive treatment
before entering public waterways." This conclusion was supported
by another study which cited the low tolerance of aquatic organisms
to certain trace elements as the major reason for controlling run-
off.2
The Agency acknowledges that the surface area of the
active portions of a land treatment facility will generally be
large, relative to the active portions of landfills. Consequently,
more extensive run-on diversion structures and run-off collection
systems will be needed at land treatment facilities. The overall
impact of run-on and run-off controls is expected to be somewhat
35
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tempered since most land treatment facilities already have
diversion structures and collection systems. 36 The Agency does
not anticipate that all the run-off that is collected at land
treatment facilities will require treatment prior to discharge.
Evidence in the literature suggests that if the waste is thoroughly
incorporated into the soil, contamination of run-off can be
minimized or prevented. At an oily waste land treatment facility
in Texas, Raymond and his co-workers found that after thorough
waste incorporation, there was no significant difference between
the quality of run-off from experimental and control plots.37
Agricultural pesticide run-off studies have shown that run-off
quality improves with the length of the storm event and with the
length of time since the last pesticide application.2 These
phenomena are paralleled in land treatment facilities.
These studies strongly suggest that run-off may need
treatment only during certain periods, for example, run-off that
is collected at the beginning of a storm event or immediately
after waste has been applied. Once wastes have been incorporated
into the soil, and the wastes have been degraded or the soil
surface stabilized by crusting or vegetation, collected run-off
is expected to require little or no treatment.
A 12-month delay for compliance with these regulations
is given so that existing facilities may construct new run-off
control systems or upgrade existing systems, including those for
run-off treatment and disposal.
D. Final Regulatory Language
36
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§265.272 General Operating Requirements [Interim Final]
(a) Hazardous waste must not be placed in or on a land
treatment facility unless the waste can be made less hazardous or
non-hazardous by biological degradation or chemical reactions
occurring in or on the soil.
(b) Run-on must be diverted away from the active
portions of a land treatment facility.
(c) Run-off from active portions of a land treatment
facility must be collected.
[Comment: If the collected run-off is a hazardous waste under
Part 261 of this Chapter, it must be managed as a hazardous waste
in accordance with all applicable requirements of Parts 262, 263,
and 265 of this Chapter. If the collected run-off is discharged
through a point source to waters of the United States, it is
subject to the requirements of Section 402 of the Clean Water
Act, as amended.]
(d) The date for compliance with paragraphs (b) and
(c) of this Section is 12 months after the effective date of this
Part.
2. Issue; Waste Analysis
a. Proposed Regulation and Rationale
The waste analysis requirements in §250.43 of
the proposed regulations applied waste analysis to all treatment,
storage, and disposal facilities, including land treatment. The
waste analysis requirements included: determination of the
hazardous constituents and properties of the waste prior to
initial disposal; verification of certain properties of each
37
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waste shipment received; and periodic, comprehensive analysis of
waste if there were indications of changes in composition.
The reasoning behind the proposed recordkeeping
requirement is discussed in the background document on waste
analysis. In brief, the purpose was to ensure that a facility
owner or operator had sufficient current information to manage
the waste without endangering human health and the environment.
(b) Comments/Responses to Comments
Comments on the proposed waste analysis
requirements are discussed in the background document on waste
analysis. As a result of these comments/ the Agency has restruc-
tured the waste analysis requirements. The final interim status
regulations for waste analysis, §265.13, require each owner or
operator to develop a waste analysis plan that specifies what
analyses are necessary to comply with the regulations. This
approach provides significantly more flexibility for the
owner/operator. The Agency has also included some minimal waste
analysis requirements that are specific to the type of waste
management facility.
For land treatment, the Agency considers the
waste analyses essential:
0 determination of the concentrations of
arsenic, barium, cadmium, lead, mercury,
selenium, and silver if these substances
are present in the waste at levels which
exceed the maximum concentrations for
characteristics of EP toxicity, contained
in Table I of §261.24;
38
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0 determination of the concentrations of
any substance which caused the waste to
be listed as a hazardous waste; and
0 determination of the concentrations of
arsenic, cadmium, lead, and mercury if
food-chain crops are grown.
The first two waste analysis requirements are
necessary to determine whether the waste is amenable to disposal
in a land treatment facility, i.e., treatable in a soil system
and prevents waste constituents from migrating through the soil
into ground water. The owner or operator of a land treatment
facility must be aware of the presence of hazardous waste consti-
tuents in the wastes he manages in order to use appropriate tech-
niques (e.g., modified application rates, pH controls, fertilizing)
to properly manage the waste.
The information obtained from waste analysis
is also needed to determine appropriate application rates and to
develop the unsaturated zone monitoring plan required under §265.278,
The rationale for requiring the owner or
operator to determine the concentrations of arsenic, cadmium,
lead, and mercury, if food-chain crops are being grown on the
site are presented in the discussion on food-chain crops later in
this document.
C. Final Regulatory Language
§265.273 Waste Analysis
In addition to the waste analyses required by §265.13,
before placing a hazardous waste in or on a.land treatment
39
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facility, the owner or operator must:
(a) Determine the concentrations in the waste of any
substances which exceed the maximum concentrations contained in
Table I of §261.24 of this Chapter that cause a waste to exhibit
the EP toxicity characteristic;
(b) For any waste listed in Part 261, Subpart D, of
this Chapter, determine the concentrations of any substances
which caused the waste to be listed as a hazardous waste; and
(c) If food-chain crops are grown, determine the
concentrations in the waste of each of the following constituents:
arsenic, cadmium, lead, and mercury, unless the owner or operator
has written, documented data that show that the constituent is
not present.
[Comment: Part 261 of this Chapter specifies the substances for
which a waste is listed as a hazardous waste. As required by
§265.13, the waste analysis plan must include analyses needed to
comply with §§265.281 and 265.282. As required by §265.73, the
owner or operator must place the results from each waste analysis,
or the documented information, in the operating record of the
facility.]
3. Issue; Growth of food-chain crops
A. Proposed Regulation and Rationale
The proposed regulations prohibited growing of
food-chain crops on the treated area of a land treatment facility.
This requirement/prohibition was not included in the proposed
interim status standards. However, after further consideration,
the Agency has decided that this standard meets the criteria
40
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established by the Agency for interim status standards and serves
important environmental objectives.
The purpose of the proposed regulations was to
protect humans from consuming toxic materials that may contaminate
human or animal food grown on land to which hazardous waste has
been applied.
Several routes exist by which food-chain crops
grown on land treatment facilities may be contaminated by hazardous
waste constituents. These are: (1) uptake by plants of the
hazardous constituent from the soil, and transfer to the edible
portion of the plant, (2) adherence of a waste to crop surface,
and (3) ingestion of the waste by grazing animals.
There are many factors which influence the degree
to which various hazardous constituents may be transferred along
these routes. These include: the chemical, physical, and biological
characteristics of the waste; the method of application; the rate
of application; season; climate; soil characteristics (including
soil type, moisture content, pH, cation exchange capacity of the
soil (CEC), hydrous-oxide content, and biological and microbio-
logical activity); the type of crop grown; the method of planting;
time and method of harvest, etc.
The information available on the extent to which
organic or inorganic substances are actually translocated to
crops is limited. Many of the studies which have been done are
the subject of a great deal of controversy. For example, many
studies failed to include pH effect on metal accumulation, thus
the knowledge of pH effect on metal accumulation is insufficient.
41
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Also, there are varying opinions on the validity of extrapolating
greenhouse data to represent actual field conditions.
In addition to the difficulties involved with
predicting and controlling the various factors which influence
the transfer of hazardous constituents to food chain crops, there
is only limited information available regarding "safe" levels of
various substances in crops. Although the Food and Drug Adminis-
tration expresses concern about the growing of food chain crops
on waste amended soils, no quantitative guidance, except for
PCBs*, has been given as to what levels of toxic metals or other
hazardous constituents in crops would protect human health.
Also, presentations in the literature on this
subject do not always clearly distinguish plant toxicity from
animal toxicity. It is recognized that toxic effects to crops
can provide some protection for crop consumers (animal and human).
However, accumulation of hazardous constituents in crops without
signs of plant toxicity creates the opportunity for human exposure
to potentially harmful substances. The reported levels of
hazardous constituents in crop tissues are sometimes subject of
misinterpretation. Care is not always taken to distinguish
between data on the edible and nonedible portions of the crop.
However, even the "nonedible" portions of the crop may be used
for animal feed so that a particular hazardous constituent may
still enter the food chain. Also, nonharvested portions of
* Finished animal feeds are the only crops for which FDA has
set a PCB tolerance level. This tolerance level is 1.2 ppm
in feeds that are given to animals consumed by humans.
42
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the crop may remain in the soil where the hazardous constituents
could contribute to increases in soil levels.
While the state of knowledge about translocation
of hazardous constituents to crops is incomplete, the Agency does
have information to suggest that there is a significant cause for
concern that translocation of some of the hazardous constituents
to food crops could endanger public health.
The cause of the Agency's concern regarding growth
of food-chain crops on land treated with waste is exemplified by
a variety of actual incidents, studies, and projections. It
should be noted that although many of the incidents described
here do not relate specifically to land treatment of hazardous
wastes, the concerns they raise are still pertinent to this
program. The concerns relate to ingestion by animals, vaporization
or direct adherence to crops, and plant uptake.
It is known, for example, that almost any hazardous
waste could be translocated through direct ingestion by grazing
animals. Soil is ingested by grazing animals along with herbage
from the adhering to leaves, from soil on roots, and from earth-
worm casts. In the case of a land treatment site, the soil is
likely to be a mixture of soil and waste. Factors influencing
soil/waste ingestion include the type of animal, the type of soil
and type of forage, stock density and other management variables,
rainfall, and earthworm populations. 15,16
Grazing animals have been estimated to ingest soil
in amounts ranging from 2 to 14 percent of the diet.17 Healy has
shown that soil can make up as much as 8 percent of the dry matter
-------
intake of grazing cattle.18 Furthermore, cattle have been observed
grazing on land used for the application of industrial sludges.19
In 1976, in Bloomington, Indiana, municipal sludge
laden with PCBs was applied to pasture land which was grazed by a
single dairy cow. The PCB levels of the sludge ranged from 240
to 1,700 ppm and soil levels in the pasture reached 200 ppm PCBs.20
As a result of grazing in this pasture, the cow's milk contained
5 ppm PCBs (fat basis), and was thus not fit for human consumption.
(The FDA tolerance for unavoidable PCBs in milk shipped interstate
commerce is 1.5 ppm.)
Other instances of the transfer of toxic organic
compounds from pasture soil to grazing animals have been reported.
In Gossimer, Louisiana, hexachlorobenzene was accidentally
spilled onto pasture land, resulting in the impoundment of 20,000
cattle, until levels of the contaminant in these animals were
reduced.21 In Maryland, heptachlor used for the control of
weevils in alfalfa was later found to have contaminated the milk
of grazing animals.22 Harrison et al., have shown that soil
containing DDT residues can supply considerable amounts of total
DDT to ewes and that these residues can be transferred to lambs.2^
Some organic wastes may vaporize and redeposit on
the tissue of plants. While few studies have been done in this area,
information has been developed which shows that lipephilic (oil)
crops like soybeans tend to take up lipophilic hyrdrocarbons like
chlorinated hydrocarbon insecticides. Also, the surface of the
leafy plants can become contaminated with small amounts of these
materials, resulting primarily from their vaporization from
44
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the soil and redeposit on the plants. The risks of the contamination
in this instance is under study.24
The adherence of toxic substances to crops is
another avenue for transfer. The likelihood of surface contamina-
tion occurring is greatest when liquid waste are applied to crops.
An example of surface contamination is a case where DDT was once
applied routinely to sweet corn in large amounts to control the
corn ear worm. It has since appeared on the surface of carrots
grown in the same fields, and has made those carrots unsuitable
for sale.21
Nearly all of the published'work on adherence of
land-applied wastes to growing crops is based on application of
municipal sludge. However, Batey, et al.. found high levels of
copper and zinc in or on crops sprayed with swine manure slurries.25
Boswell found high levels of cadmium, lead, and chromium on
foliage following application of municipal sludge filter cake.25
Chaney and Lloyd have shown that municipal sludge applied to
pasture grass can, shortly after application, result in the adhered
sludge making up 30 percent of the dry weight of the crop.26 Rain-
fall and weathering over an 80-day period did not remove much of
the sludge from the grass. However, the 80 days of growth
permitted a dilution of the weight of the sludge to the weight of
the crop. Still, at the end of the 80-day period, 5 percent of
the dry weight of the grass was actually found to be adhered
sludge. This study was performed in the rainy east, and therefore,
one would expect that sludge application to grasses in more arid
regions would result in even greater adherence of the sludge to
45
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the crops. A greenhouse study by Jones et al., using simulated
rainfall, resulted in similar conclusions to those of Chaney and
Lloyd.27 once the sludge had dried on the grass, rainfall was
not effective in reducing the amount of adhered sludge. Rainfall
was found only to be effective if it occurred immediately after
sludge was applied.
Heavy metals, such as cadmium, molybdenum, selenium,
mercury, and lead, can be absorbed by crops from the soil of land
treatment facilities. The uptake of mercury and lead by most
crops, however, is not nearly of the magnitude of these other
metals.
Cadmium may be taken up by plants even though only
very low levels exist in the soil. The transfer of cadmium from
the soil to plants is well documented in the background document
supporting EPA1s recently promulgated Criteria for Classification
of Solid Waste Disposal Facilities and Practices. Crops such as
leafy vegetables or root crops take up significantly greater
amounts of cadmium than do grains or grasses.
Maintaining a near-neutral pH on a land treatment
facility to control plant uptake of most heavy metals can lead to
an increase in the uptake of molybdenum and selenium. These two
metals are more soluble at neutral and basic pH's. Molybdenum's
toxicity has been a serious problem in livestock food production
in certain areas of the western United States. Forages grown on
naturally wet, alkaline, or neutral soils can contain toxic concen-
trations of molybdenum.28 Certainly, the land application of
wastes high in molybdenum to such soils would aggravate this
naturally-occurring problem.
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In Oregon, a study using shredded municipal waste
at an application rate of 900 metric tons per hectare resulted in
a significant uptake of molybdenum by alfalfa. The levels reached
would have been potentially hazardous to livestock if only one
feed source was used.29
Land treated wastes do not generally increase
levels of mercury in plants. However, Van Loon found very con-
siderable levels of mercury in tomatoes where municipal sludges
(the highest containing 25 ppm mercury) were used.27,32 Results
of Yugoslav studies showed that mercury levels of most plants
were low ( 1 to 50 ppb) compared to the mercury content of soils
in which they grew (100 to 600 ppm). Carrots, grasses, and some
weeds had more mercury (800 ppb) than other plants. Jackson
found that mercury in the tops of barley and soybean plants whose
roots were in a mercury solution came from mercury vapor released
from the roots, rather than from translocation. If mercury vola-
tilizes from waste-treated soils, plants could absorb it.30
Significant increases in the lead content of some
crops as a result of soil application of lead have been reported,
particularly in soils deficient in phosphate. Because of the
buffering capabilities of soils and plant roots, as well as
absorption and precipitation phenomena, most lead in soils is not
likely to be translocated to the above-ground portions of plants.
However, uptake to the above-ground portions can be appreciable
following changes in the environmental and physiological condition
of the plant.33 in fact, investigations of existing land treatment
sites have indicated that significant increases can occur in the
47
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lead content of crops, such as clover and various grasses.30
In general, a minimal amount of toxic organic
compounds are absorbed by plant roots and transferred to other
parts of the plant. Organics with large molecules, such as pesti-
cides and PCBs, do not tend to pass the semipermeable membrane of
plant roots. Consequently, plants posses the ability to exclude
large organic molecules added to soils, which result in minimal
impact on the quality of forage and grains.32 An exception is
organochlorine pesticides which are absorbed by plant roots and
transferred to other parts of the plant, but at a very low rate
compared to the concentration in the soil.3-*
The absorption of PCBs by plant roots and trans-
location within plants is considered minimal, but some studies
have reported what appeared to be low levels of plant uptake as a
result of heavy application rates.34 These studies further
suggest, however, that PCBs are not actually taken up by the plant
but, rather, are physically adsorbed on the surface of the roots.32
The examples do suggest that there are known cases
where translocation of toxic substances to crops has occurred,
and that there is a significant potential for contamination of crops
from soils treated with hazardous wastes to crops grown on that soil,
Although not legally required, the Agency also
examined the benefits to be gained from growing food-chain crops
in treated soils. The Agency believes that such benefits are mini-
mal. Certainly the very small amount of land so used is not needed
for good growth from a national perspective. It represents a
negligible portion of the total productive land for crop
48-49
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growth available in this country. Furthermore, there are other
productive uses of such land, for example, crop farming of non-food-
chain crops, if crop growth is desired. The Agency recognizes that
growth of food-chain crops can result in a source of revenues to
help defray disposal costs. However, the Agency does not believe
that such revenues minus the cost of growing and marketing the
crops, especially in light of the cost of waste and crop monitoring
and other controls needed to ensure protection of public health, are
significant to the economic viability of land treatment.
The Agency considered the alternative of specifying safe
application rates of various wastes to the soil for growth of food
crops. The Agency also considered establishing safe levels of various
substances in plants and requiring crop monitoring to control
potential hazards. As the above discussion points out, the data
and information base available for such an approach does not exist.
In view of all of the above considerations, the Agency concluded
that it should ban the growth of food-chain crops on hazardous
waste land treatment facilities.
B. Comments on the Proposed Regulation
0 The term "food-chain crops" means tobacco; crops
grown for human consumption; or crops grown for pasture,
forage, or feed grain for animals whose products are
consumed by humans.
0 The regulation is too restrictive. If studies of
plant tissue residues and crop uptake demonstate that
the crop will not take up the hazardous constituents,
growth should be permitted.
8 The restriction will abolish the practice of growing
food chain crops at land treatment facilities. EPA
should require tests to determine if crops grown on
such land are suitable for consumption by humans or
livestock
50
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Growth of food-chain crops should be permitted if, after
study over two growing seasons, the consumable part of
the crop can be shown to be non-toxic.
The regulation is too restrictive. It should be
replaced with a requirement for monitoring of crop
uptake of hazardous constituents.
The regulation is too restrictive. The regulations
should take into consideration the hazardous characteristics
of the waste, the nature of the soil, and the substance
being taken up by crops. Growth should be allowed.
The regulation should be based on application rates of
waste, rather than a prohibition. EPA should develop
regulations controlling application and specifying
testing requirements.
The issue is blown out of proportion. Many hazardous
wastes are phytotoxic, which makes growth of any crop
impossible. However, other wastes are amenable to land
treatment on crop land.
Growth of food-chain crops should not be prohibited
without qualification. Certain crops and grasses have
assimilative capacity for a variety of potential
hazardous waste, e.g., bermuda grasses. Without their
use, land treatment facilities would have to be bigger.
The prohibition is inconsistent with EPA's position on
POTW sludge. Textile sludges present no greater toxic
potential than POTW sludges.
Studies have shown that land treatment of utility ash
and sludge do not result in unsafe levels of potentially
hazardous contaminants in crops. Gypsum and fly ash
are used routinely to correct soil deficiencies. An
exception should be provided where reasonable evidence
and studies show that there is no substantial hazard
to human health.
The regulation would prohibit using waste lime as a
soil conditioner on crop lands. Waste limes from the
sugar beet refining process or from lime kilns have
high levels of CaCO3 (85 percent) and MgC03 (5 percent),
which neutralize acid soils. Waste lime from beet
processing has been in use for 25 yeafirs.
Crude oil does not have as high a concentration of
heavy metals as other waste oils. It has been
demonstrated that waste crude oil adds nutrient value
and that it is perfectly safe to grow crops on land so
treated.
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0 The regulation would eliminate land treatment of waste
for beneficial uses, i.e./ as agricultural fertilizers.
It would raise disposal costs by 700 percent. Thus,
•there is a poor risk and benefit ratio for a ban.
0 The prohibition is totally appropriate, since there is
very little information on toxics and persistent
organics beyond the work on metals in POTW sludges.
Until data are developed on crop uptake of these other
toxins, land contaminated with them should not be used
for agricultural purposes.
C. Response to the Comments
1. Food chain crops should be defined.
A definition for "food chain crops" was provided in the
proposed rules on page 58997, Section 250.41( b) (33) . The same
definition is included in the final interim status regulations. The
definition reads: "Food chain crops" means: tobacco? crops grown
for human consumption; or crops grown for pasture, forage, or feed
grain for animals whose products are consumed by humans." This
definition does not preclude the growing of a crop which is normally
consumed by humans or animals if the crop is only grown as a ground
cover and then plowed under.
2. Monitor crop uptake.
The option of analyzing a crop for uptake of hazardous
constituents is conceptually attractive, but presents certain
problems in practice. The most basic problem is that the Food and
Drug Administration has not established crop tolerance levels for
most of the hazardous constituents of concern; hence, there is no
standard of comparison.
However, the Agency does believe that crop monitoring represents
an acceptable general approach when comparing hazardous constituents
in the crops to background levels. Comparing crops grown on land
52
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treatment facilities with crops grown in nontreated soils is the
only feasible way of applying crop monitoring in most situations,
due to lack of defined tolerance levels. The revised regulatory
language permits an owner or operator to present such data to the
Agency as a part of the support for a claim that growth of a crop
on a land treatment facility presents no danger to public health.
3. Prescribe acceptable application rates. Base the standard
on the characteristics of the waste/ the soil, and the
crop being grown. Many wastes are amenable to land
treatment on cropland.
This approach, perhaps coupled with crop monitoring, would
be an ideal approach if the state-of-the-art would support it.
Unfortunately, this is not the case. Except for cadmium,
information on acceptable application rates is not available for
combinations of soil, hazardous wastes, and crops. Consequently,
this approach is not feasible as a general approach at this time.
Such an approach is used for cadmium, however, because there is
sufficient data to support it. However, the Agency believes that
it is important to begin to develop this information through monitorir
of conditions in a land treatment facility. Furthermore, the Agency
believes that an owner or operator should have the opportunity to
demonstrate to the Agency that it has developed such information
for a particular situation. This concept is embodied in the interim
status standards.
4. Certain crops and grasses have assimilative 'capacity for
potentially hazardous substances, e.g., bermuda grasses.
The regulation should be qualified to allow their growth.
The proposed regulation is not without qualification in
that only food chain crops are restricted. Crops which are not
used for human consumption or consumed by animals whose products are
53
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not consumed by humans are not restricted. Therefore, a crops such
as burmuda grass can be grown at a land treatment site for the
purpose of assimilating waste components or providing ground cover-
In this case, the grass could not be used as an animal feed for
animals whose products are consumed by humans. Because a food
chain crop is defined by its end use, crops which may normally be
considered food chain crops can be grown on the landfarm if adequate
measures are taken to prevent its consumption by humans or animals
whose products are consumed by humans.
5. The prohibition is inconsistent with Subtitle D regulations.
Textile sludges present no greater hazard to crop growth
than wastewater treatment sludge.
The Agency agrees that the approaches are currently
different. However, the cadmium standards established in the
Criteria have been incorporated into the interim status standards
in order to have consistency between those two regulations. The
requirements concerning PCB in the Criteria were not included at
this time. This issue will be resolved as part of the consideration
between the RCRA programs and the Agency program for handling PCB
under the Toxic Substance Control Act. Also, the interim status
standards will provide an owner or operator the opportunity to
present data showing that crop growth on such waste is safe.
6. Utility ash and sludge is beneficial to some solids;
presents no hazard to crops.
The interim status standards will allow an owner or operator
to grow food chain crops at a land treatment facility, provided he
has data indicating that such a practice does not pose a threat to
public health. Therefore, an owner or operator at a land treatment
facility receiving utility ash and/or sludge may grow food chain crops
provided he can document that such crops are safe.
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7. The regulation would prohibit using waste lime as a soil
conditioner on crop lands.
The Agency acknowledges the point raised by this comment
and has exempted waste lime from this prohibition if it is only
clasified as a hazardous waste due to its high pH. This provision
is specified in Part 261.
8. Crude oil adds nutrient value to the soil, and crop growth
on land so treated is safe.
As with all waste which is classified hazardous, the interim
status standards will allow an owner or operator to grow food chain
crops at a landtreatment facility provided he has data indicating
that such a practice does not pose a threat to public health.
9. The prohibition wold eliminate land application of hazardous
waste for use as agricultural fertilizers and raise disposal
costs by 700 percent.
No data to support the claim of a 700 percent cost increase
were provided, and the Agency disagrees strongly with this estimate.
Since the prohibition only applies to the growing of crops for
human consumption or for consumption by animals whose products are
consumed by humans, the Agency does not believe that this restriction
will result in a major impact on the landfarming of hazardous
wastes. Because food chain crops often have a higher market value
than non-food-chain crops, there may be some reduction of income from
landfarms. However, because many non-food-chain crops are often
grown on less productive lands, the agricultural fertilizer value
of the hazardous wastes may be better utilized by these crops.
Thus, the Agency sees no clear or significant benefit from growing
food chain crops.
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10. Summary
The Agency proposed a ban on the growth of food-chain
crops at hazardous waste land treatment facilities. After reviewing
comments, EPA decided that during the interim Status period, food-chain
crops may be grown, provided that certain requirements are met.
The Agency's decision not to continue with the ban during the
interim status period is based on the following reasons: First,
there exist insufficient data to indicate that the growth of food-chain
crops at a hazardous waste land treatment facility would always
create a risk to those who consume such crops. Second, banning the
growth of food-chain crops, would be inconsistent with the regulatory
approach taken to protect food-chain crops under Subtitle D of
RCRA. These regulations were finalized as the Criteria for
Clasification of Solid Waste Disposal Facilities and Practices (40
CFR 257) on September 13, 1979.
The Agency believes it would be unjustified to impose a ban on
the growth of food-chain crops at land treatment facilities if
there were convincing evidence that the crops can be grown without
posing a significant public health risk. It is conceivable that a
substance in a hazardous waste may not be taken up by certain
food-chain crops, or after a period of treatment, the substance
may degreade into products non-hazardous to humans.
For example, some wastes may be used to control pH of the
soil, and there may be a significant body of data which supports
that such a use does not pose a public health risk. The Agncy does
not wish to prohibit such uses of waste, realizing that the waste may
simply be replaced with commercial product containing the same
chemical constituents as the waste.
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The cadmium standards detailed in the Criteria do not set
limits for food-chain crops, but instead prescribe annual application
rates and limits on cumulative loading based on the specific health
risk posed by cadmium. As a result, a waste, regardless of the
cadmium concentration, may be applied to land on which food-chain
crops are grown. Compliance with the Criteria can be achieved
merely by applying less waste. The Agency believes it would be
unjustified in banning the growth of food-chain crops at facilities
receiving waste that is hazardous due to cadmium, since such a waste
can be applied in a manner that would not violate the standards
prescribed in the Criteria.
The Agency, while not considering a ban appropriate because of
the reasons mentioned, had to deal with the task of how to structure
the regulations to permit the growth of food-chain crops, and at
the same time be assured that public health would be protected. In
order to achieve this, the Agency devised a two-part test to determine
whether food-chain crop growth on land treatment facilities is
acceptable. The two-part test requires the owner or operator,
prior to growing a crop, to demonstrate that the hazardous waste
constituents in the waste, as well as arsenic, lead and mercury
will not (1) be transferred to the edible portion of the crop by
plant uptake, by direct contact or by transfer to food-chain animals;
or (2) occur in greater concentrations in the crop than in crops
sft
grown on control soils under similar circumstances in the region.
In order to demonstrate comparability, an owner or operator
must use actual field studies. A test plot would be considered
an acceptable field study. Also, the conditions under which the
comparable crops are grown must be similar to the conditions found
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at the facility- For example, soil type, soil moisture, soil pH,
soil nutrients, photo period and length of growing season, must be
similar at both facility and control sites. The owner or operator
must also document the sample selection criteria, sample size
determination, analytical methods and statistical procedures used to
make the demonstration. In order to determine the compliance prior
to waste application, the owner or operator must pre-test samples of
the crop using the type of waste and application rate that will be
used at the facility. The sample must be that portion of a crop
which would be consumed, e.g., corn kernel, wheat grain etc.
The two-part test approach is based on the premises that since
the Agency does not have a clear specification of the "no risk"
level of such contaminants in food crops, it is reasonable to assume
that the level of such contaminants presently in food crops is
acceptable. However,- future research data may indicate that health
tolerances in food crops should be higher or lower than the average
levels otherwise present in such crops.
Arsenic, lead,, and mercury were specifically identified
because of their relatively high toxicity to humans and evidence
that they can be taken up by crops (38). Mercury can enter plants
through the roots and be readily translocated throughout the plant.
Arsenic tends to accumulate in the roots of most crops, which is a
concern when root crops such as radishes, carrots, etc., are grown.
When in high concentrations in the soil, lead has been shown to
translocate to crops.
The Agency is concerned that there are other hazadous substances
in the wastes, e.g., toxic organics, that may be taken up by crops.
58
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The difficulty in identifying toxic organics is due to the lack of
data in this area. Most crop studies have addressed only inorganics:
thus there is a paucity of data on the uptake of toxic organics by
crops. However, the Agency will identify other hazardous substances
of concern as information becomes available.
In order to be consistent with the Criteria for the Classification
of Solid Waste Disposal Facilities and Practices, the standard
developed in those regulations for cadmium has been incorporated
into the interim status regulation. Thus the cadmium standard
present in the Criteria will be applicable to hazardous waste land
treatment facilities.
The Criteria include two approaches for the land application
of wastes containing cadmium. The first approach incorporates four
*
site management controls; control of the pH of the waste and soil
mixture; annual cadmium application limits that are reduced over
time; cumulative cadmium application limits based on soil cation
exchange capacity (CEC); and restriction of the cadmium concentration
in waste applied to facilities where tobacco, leafy vegetables and
root crops are grown.
The second approach allows unlimited application of cadmium
provided that four specific control measures are taken: first, the
crop grown can only be used as animal feed. Second, the pH of the
soil must be maintained at 6.5 or above for as long as food-chain
crops are grown. Third, a facility operating plan must describe
how the animal feed will be distributed to prevent human ingestion:
Fourth, future owners are provided notice (through provisions in
land records of property deed) that there are high levels of cadmium
in the soil and that food-chain crops should not be grown.
59
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The Agency has added a provision to the interim status
regulations that requires owners or operators of land treatment
facilities on which food-chain crops have been grown, or are going
grown, to notify the Regional Administrator within sixty (60) days
after the effective date of the regulations if they intend to grow
food-chain crops in the future. In addition a note in the regulation
apprises an owner or operator, who for the first time grows food-
chain crops after the effective date of the regulation, that he has
made a change in process and must notify the Administrator under
Section 122.23(c)(3) of the consolidated permitting regulations.
These notification procedures are designed to give the Regional
Administrator notice of those facilities that are engaging in the
environmnentally sensitive activity of applying hazardous waste to
food-chain crops. This information will assist the Regional
Admnistrator in the establishment of priorities for permitting.
It is the Agency's firm belief that growth of food-chain crops
on land contaminated with hazardous waste is an issue which should
be dealt with cautiously, and should be practiced only where there
is convincing evidence that it poses no threat to public health.
In the opinion of the Agency there is little need to grow food-
chain crops at land treatment facilities. The small amount of land
use for land treatment represents a negligible portion of the total
productive land available for crop growth in the Unitd States.
Furthermore, there are other productive uses of the land, such as
ornamental horticulture, growth of fiber crops or other non-food crops
The Agency recognizes that growth of food-chain crops can
result in a source of revenue to help defray disposal cost. However,
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the Agency does not believe that such revenues, minus the cost of
growing and marketing the crops, are significant to the economic
viability of landtreatment, especially in light of the cost of
monitoring wastes and crops and other controls needed to ensure the
protection of public health.
D. Final Regulatory Language
§265.276 Food-chain crops
(a) An owner or operator of a hazardous waste land treatment
facility on whirh food-chain crops are being grown, or have been
grown and will be grown in the future, must notify the Regional
Administrator within 60 days after the effective date of this Part.
[Comment; The growth of food chain crops at a facility which has
never before been used for this purpose is a significant change in
process under §122.23(c)(3) of this Chapter. Owners or operators
of such land treatment facilities who propose to grow food chain
crops after the effective date of this Part must comply with
§122.23(c)(3) of this Chapter.]
(b)(l) Food chain crops must not be grown on the treated area
of a hazardous waste land treatment facility unless the owner or
operator can demonstrate, based on field testing, that any arsenic,
lead, mercury, or other constituents identified under §265.273(b):
(i) Will not be transferred to the food portion of the crop
by plant uptake or direct contact, and will not otherwise be ingested
by food chain animals (e.g., by grazing): or
(ii) Will not occur in greater concentrations in the crops
grown on the land treatment facility than in the same crops grown
on untreated soils under similar conditions in the same region.
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(2) The information necessary to make the demonstration
required by paragraph (b)(l) of this Section must be kept at the
facility and must/ at a minimum:
(i) Be based on tests for the specific waste and application
rates being used at the facility; and
(ii) Include descriptions of crop and soil characteristics,
sample selection criteria, sample size determination, analytical
methods, and statistical procedures.
(c) Food chain crops must not be grown on a land treatment
facility receiving wasts that contains cadmium unless all requirements
of paragraph (c)(1)(i) through (iii) of this Section or all
requirements of paragraph (c)(2)(i) through (iv) of this Section
are met.
(1) (i) The pH of the waste and soil mixture is 6.5 or
greater at the time of each waste application, except for waste
containing cadmium at concentrations of 2 mg/kg (dry weight) or less;
(ii) The annual application of cadmium from waste does not
exceed 0.5 kilograms per hectare (kg/ha) on land used for production
of tobacco, leafy vegetables, or root crops grown for human
consumption. For other food chain crops, the annual cadmium
application rate does not exceed:
Annual G3
Application Pate
Time Period (kg/ha)
Present to June 30, 1984 2.0
July 1, 1984 to Dec. 31, 1986 1.25
Beginning Jan. 1, 1987 0.5
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(iii) The cumulative application of cadmium from waste does
not exceed the levels in either paragraph (c)(1)(iii)(A) of this
Section or paragraph (c)(1)(iii)(B) of this Section.
Maximum cumulative application (kg/ha)
Soil cation Background soil pH Background soil pH
exchange capacity less than 6.5 greater than 6.5
(meq/lOOg)
less than 5 5 5
5-15 5 10
greater than 15 5 20
(B) For soils with a background pH of less than 6.5, the
cumulative cadmium application rate does not exceed the levels
below: Provided/ that the pH of the waste and soil mixture is
adjusted to and maintained at 6.5 or greater whenever food chain
crops are grown.
Soil cation exchange capacity Maximum cumulative
(meq/lOOg) application (kg/ha)
less than 5 5
5_!5 10
greater than 15 20
(2) (i) The only food chain crop produced is animal feed.
(ii) The pH of the waste and soil mixture is 6.5 or greater
at the time of waste application or at the time the crop is planted,
#
whichever occurs later, and this pH level is maintained whenever
food chain crops are grown.
(iii) There is a facility operating plan which demonstrates
how the animal feed will be distributed to preclude ingestion by
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humans. The facility operating plan describes the measures to be
taken to safeguard against possible health hazards from cadmium
entering the food chain, which may result from alternative land use.
(iv) Future property owners are notified by a stipulation in
the land record or property deed which states that the property has
received waste at high cadmium application rates and that food
chain crops should not be grown, due to a possible health hazard.
[Comment: As required by §265.73, if an owner or operator grows
food chain crops on his land treatment facility, he must place the
information developed in this Section in the operating record of
the facility.]
4. Issue; Soil monitoring
a. Proposed Regulation and Rationale
The proposed interim status regulations required soil
monitoring only as it related to closure. Those requirements will
be discussed in the section of this document dealing with closure.
The other soil monitoring requirements of the proposed regulations
were not included in the proposed interim status standards. However,
after further consideration, the Agency has determined that soil
monitoring serves an important environmental objective and meets
the criteria established by the Agency for interim status standards.
Soil monitoring is necessary during interim status because it is an
indicator of how well the land treatment process is working.
The proposed soil monitoring requirements included:
0 Determine background soil conditions by taking one soil core
per acre in the area to be treated at a depth of three times
the depth of the zone of incorporation, or 30 centimeters,
whichever is greater. The bottom one-third of the soil core
must be analyzed for the hazardous constituents in the waste.
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At new facilities, the cores must be taken prior to beginning
operation. At existing facilities, the cores must be taken
within six months of the effective date of the regulations.
0 Soil conditions in the treated area of a landfarm must be
determined by taking one soil core per acre semiannually at
three times the depth of the zone of incorporation, or 30
centimeters, which is greater. The bottom one-third of the
core must be analyzed for the hazardous constituents in the
waste.
0 If soil monitoring shows that the concentration of a
hazardous constituents significantly exceeds background
levels, the owner/operator must: (1) notify the Regional
Administrator within seven days, (2) determine the areal
extent of vertical contaminant migration, and (3) discontinue
all land treatment in the contaminated area until corrective
measures are taken.
There were three basic elements to this proposed procedure,
each with a separate rationale. These elements were the sampling
procedure (i.e., number of samples), the depth of the core samples,
and the corrective action required. The sampling procedure was
based largly on subjective reasoning of how many samples would be
required to obtain an adequate representation of the soil in the
landfarm. The requirement was not based on a statistical test.
The corrective actions specified were based on the assumption
that migration of contaminants to a depth of three times the depth
of the zone of incorporation constituted a potential threat to
public health and the environment, and that no further land treatment
should occur until this situation was corrected, as determined by
the Regional Administrator.
Perhaps the most significant element of the requirement was
the selected depth of three times the depth of the zone of
incorporation as the "performance standard" for the facility. This
standard was based on a number of technical studies which suggested
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that in a properly designed and operated land treatment facility,
there should be little or no migration of contaminant beyond the
zone of incorporation.
The Agency has identified a considerable amount of literature
and empirical data indicating limited waste migration at hazardous
waste land treatment facilities.
A literature review by Page6 in 1974, evaluated the potential
hazards of the application over 10 years of sewage treatment plant
wastes to agricultural soils. Page found that in most soils, the
percentage of heavy metals (Ag, Ba, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb,
Sn, and Zn), applied in the form of sludge which move beyond the
depth of tillage, is quite small. This same phenomenon has been
observed in field studies where oily hazardous waste has been land
treated. Meyers and Huddleston^ applied oil refinery waste (API
Separator Sludge, tank bottoms, slop oil) at three different
application rates over a period of three years. The study indicated
no significant leaching or migration of organic or inorganic waste
constituents. Similar findings were reported by Kincannon? in his
review of an 18-month field study conducted in 1971. Three types
of oil feed materials were selected to represent different combinations
of hydrocarbon types. The oil types included oil tank bottoms,
buncker C fuel oil, and waxy oil. Neither oil nor nutrients (added
as fertilizer) migrated vertically during the study.
A recent state-of-the-art study^ on land treatment of municipal
and industrial wastes found no incidents of water pollution at any of
the six sites studied. Soil sampling at these sites suggested that
heavy metals and trace elements appear to be retained in the zone
of incorporation.
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The middle section (middle one-third of core) is the buffer
zone. Even though data indicate that the extent of migration of
waste contaminants is generally limited to the zone of incorporation,
a buffer zone was provided to allow for the effects of variability
within a site, (e.g., the depth of the zone of incorporation may
vary from six to eight inches).
The lower section (bottom one-third of core) represents the
indicator zone. The presence or absence of waste contaminants in
this zone would indicate whether or not a land treatment facility
is functining properly.
An approach similar to that proposed by EPA was arrived at
independently by an EPA contractor that recently performed a state-
of-the-art study on land treatment practices.2 The report stated
i
that "a landfarm site must be properly monitored to ensure that
waste constituents are retained in the layer of incorporation.
This can be accomplished by collecting soil samples at three depths
(0 to 30 cm, 30 to 60 cm, and 60 to 90 cm) prior to site activation,
and at 3 to 6-month intervals thereafter. Soil samples collected
should be analyzed for those constituents present in the waste
which may result in water pollution problems." The only major
difference between this and the EPA approach is the contractor's
recommendation of a fixed core sample depth. The Agency considered
the variable depth related to the depth of tillage to be more
flexible in accommodating the different tillage methods that
currently exist among sites.
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b. Comments on the Proposed Regulations
1. Soil Monitoring vs. Ground-water Monitoring
0 Neches1 land treatment research supports EPA's conclusions
that soil monitoring will detect any migration long before
ground-water monitoring could detect it.
0 Ground-water monitoring at land treatment facilities is
unnecessary, especially with the proposed siting and
surface controls outlined in §250.45-5(b) and (c) .
0 Because our own data has shown little migration, we strongly
support soil monitoring in lieu of ground-water monitoring.
If, at some later time, soil monitoring indicates significant
migration, ground-water monitoring could be commenced.
0 Because the published literature clearly shows little
migration, we strongly support soil monitoring lieu of
ground-water monitoring.
0 The proposed soil monitoring program is not adequate to protect
ground water resources. Some potential ground-water
contaminants migrate slowly through soils; however, there
are many potential contaminants that can migrate very
quickly through soils, depending on soil conditions and
waste characteristics. Situations could exist where
potential ground-water contaminants would migrate to ground
water and not be detected by semiannual soil monitoring.
0 EPA could not identify a single incident of ground-water
contamination resulting from land treatment of hazardous
wastes, which would indicate that the soil monitoring
requirements are overly restrictive and should be replaced
by test wells at the property line. Soil monitoring should
be performed, but for day-to-day operations, not for
compliance monitoring.
2. Soil Monitoring
A. Sampling Procedure (Number of Samples? Extent of Analysis)
0 Analyzing for all hazardous components is unreasonable and
expensive. Should analyze only "as necessary" to detect
vertical migration of wastes. It is beyond present day
knowledge to analyze for all hazardous constituents since:
- many wastes are very complex and variable in composition
- quantitative analysis may not show biological activity
or chemical form of some components.
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- very few labs have the expertise or equipment to do
quantitative analysis of soil samples, and there are
few standardized analysis procedures
Because of the above, should analyze for indicators of
tracers, such as bromide.
Should analyze for degradation products rather than wastes,
as applied. Should change the regulation to "analysis as
necessary to detect vertical migration of hazardous
constituents."
Accumulation of waste constituents in the soil should be
compared with "acceptable" levels of those constituents
rather than with background.
The number of samples and extent of analysis is excessive
for low hazard wastes, and would be expensive ($200-$400
per sample). Should analyze only for major species unless
migration is detected. For example, large treatment areas
with uniform terrain and cover crop would hardly require
so many samples and would result in redundant data.
Analyzing for all constituents which make the waste
hazardous is overkill, also. (Comment listed 28 substances
which potentially would have to be monitored for fly ash
and scrubber sludge.) Should analyze for major species
initially, such as Ca, Na, 364, etc. If migration is
indicated, then more extensive trace analysis could be done.
No methods were provided for obtaining core samples, and
there is an absence of analysis methods and methodology
for determining background condition. Should require a
minimum of 10 background samples and not less than one per
acre.
Soil monitoring and comparison to background analyses is
too vaguely described. Suggest that a periodic report of
analyses be required and that the definition of "significantly
exceeded background levels" be more scientifically
specified.
Should define significant increase over background.
Suggest defining significant increase in terms of number
of samples, i.e.: /
Significant Increase
No. of Samples over Background
1 1.2
2 1.4
3 1.6
4 1.8
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One sample per acre is arbitrary and unreasonable. Soil
samples are time-consuming and expensive/ and should be
minimized. Five samples are sufficient—one on each corner
and one in the center of the facility, for plots of 50
acres or less.
For background purposes, one core per acre is excessive
and expensive. Should sample the four corners and middle
of the treated area. If these samples show inconsistencies,
then additional samples could be taken.
The cost of sampling large land treatment areas will be
exorbitant and for no good reason. Uniformity of the
soils in the tract can be determined by sampling of the
four corners and middle of the site.
Should allow a variance for the owner or operator to show
that his sample will give representative results.
Far fewer than one soil core per acre would accomplish
adequte testing at three times the depth of the zone of
incorporation. Testing of each acre, if necessary, should
be confined to the actual zone of incorporation.
Background and treated soil conditions car be determined
without requiring one core per acre. A more rational and
reasonable requirement would be one soil core per 10 acres,
but not less than one core per treated area.
The total number of soil core samples to be analyzed
annually is excessive and should be reduced by either
taking fewer samples per total acreage as acreage increases,
or lengthening the sampling frequency froms semiannual to
annual. Suggest the following to give adequate quantities
of soil core samples to be analyzed:
one core per acre for 5 acres or less
one core per 1.5 acres for 6 to 9 acres
one core per 2 acres for 10 to 30 acres
- one core per 4 acres for greater than 60 acres
One soil core per acre represents considerable redundancy.
Samples should be taken to represent specific areas
receiving specific wastes at particular application rates.
An area receiving a specific waste mix at a uniform
application rate throughout the area.should be treated as
a single unit for soil sampling and analysis.
Testing of a subsample of composited samples from several
different locations in an area receiving a particular waste
at a particular application rate should be allowed.
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B. Sampling at Three Times the Depth of the Zone of Incorporation
e Limiting migration to three times the depth of the zone of
incorporation is arbitrary and unreasonable. Application
to the surface should not be more limited in penetration
limits than deeper application. Migration limits should
be based on case-by-case conditions and should allow the
owner/operator to demonstrate that no ground water threat
exists.
0 Limiting migration to three times the depth of the zone of
incorporation is not acceptable. Should allow migration
to a depth safely above the shallowest usable ground water.
Some land treatment faciities may be "underlain by a hundred
feet of non-water-bearing soil capable of absorbing
contaminants.
0 Application of wastes with high solids content will raise
the surface of the land treatment facility gradually,
eventually causing problems with the definition of the
zone of incorporation. Suggest that core depths be
determined from the initial depth and location of the zone
of incorporation.
0 A fixed core depth, such as three feet, should be established
from the initial level of the zone of incorporation. The
reason is to take advantage of the assimilative capacity
of the soil to arrest transport of contaminants, yet
provide a reasonable depth for monitoring to assure that
the transport is not excessive. These requirements have
nothing to do with the depth to which the soil was plowed,
so should not be tied to that depth. This overcomes the
problem of defining a (sample) depth when waste is not
plowed at all.
0 Surface soils should be sampled as protection for the land
treatment facility operator, since soil composition can
change dramatically with depth and composition of surface
soils are subject to change due to various manmade activities
and emissions.
0 The soil monitoring requirements should be broadened to
include anaerobic operations. Aerobic and anaerobic
operations do not occur in the same locations in the soil
profile and final monitoring should not be'done until
after the last operation in the sequence. An example is
denitrification. A high nitrogen waste would yield nitrate
in the aerobic zone within 12 inches of the zone of
incorporation. Further down, the nitrate will denitrify
(convert to nitrogen gas) under proper conditions. Soil
monitoring locations do not relate to the zone of
incorporation in this case.
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The limitation on significant increase of hazardous
contaminants below the zone of incorporation is in conflict
with the planned dilution of certain inorganic ions in the
ground water, i.e., chloride. A waste may be hazardous
because of its concentrations of chloride or sulfate. It is
well recognized that the chloride does not degrade and
will eventually dilute in the ground water. This should
be recognized in the regulations.
We agree with the depth of three times the depth of the
zone of incorporation, or 30 centimeters, whichever is
greater, for taking soil samples.
Corrective Action
Requiring land treatment facilities to cease operations
and perform corrective actions upon detecting an increase
above background may force land treatment facilities to
close when no threat to underground drinking water supplies
or human health exists. Instead of requiring that operations
be discontinued, EPA should require that the magnitude of
the threat to area ground water be determined and that,
based on this analysis, the Regional Administrator may
order the land treatment facility to be closed and/or
corrective action taken. Requiring the owner/operator to
cease operations and take corrective action is justified
if human health and the environment are endangered.
However, a significant increase over background does not
necessarily constitute a threat. Soil monitoring should
be used to indicate when further investigation is warranted
to determine if corrective action is necessary.
This comparison with background and corrective action
restricts the mechanism by which land treatment functions.
Concentrations of constituents added to a landfarm will
certainly increase in the zone of incorporation and, to
lesser extent, at the depths cited. Otherwise, such
constituents would have had to be discharged either to
ground or surface waters. The fact that background levels
have been exceeded in no way demonstrates that the soil's
capacity for assimilation has been reached. The regulation
should establish "safe levels" at which constituents can be
applied and assimilated.
The requirement that operations be discontinued until the
Regional Admiminstrator determines what actions are to be
taken is unnecessarily strict and violates due process.
It is too stringent because it ignores the possibility of
analytical error, the importance of the finding in the
particular circumstance, and the consequences of the close-
down decision. It should be sufficient to require immediate
notice to the Administrator and, perhaps, the requirement
to conduct more frequent sampling and analysis. The
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Regional Administrator always has recourse to the imminent
danger provisions of RCRA Section 7003. The proposal
violates due process rights of the owner/operator, as no
standards are established for RA determinations, nor is
the RA required to make his determination within a particular
time. Thus, the RA has absolute discretion, both as to
when he will make a decision and what the decision will be.
0 Merely detecting contaminants below the zone of incorporation
does not constitute a threat to ground water. The
regulations seem to assume that any migration of contaminants
to poses a hazard to ground water. This assumption is not
true. Soil monitoring is a useful tool that should not be
relied upon totally to provide ground, water protection.
" In the event that a significant increase of hazardous
constituents appears below the tilled depth, what is the
recommended correction procedure? Complete removal and
landfilling of the fill? Is it presumed that this senseless
approval of land spreading of hazardous waste is an attempt
to justify the advocation of extensive and almost uncontrolled
sewage sludge farming?
C. Response to the Comments
1. Soil Monitoring Versus Ground-Water Monitoring
Comments received on this issue clearly favored some form
of soil monitoring over ground-water monitoring, however, several
commenters felt that ground-water monitoring was also necessary.
These commenters contended that soil monitoring had certain
limitations (e.g., low reliability) of detecting highly mobile
contaminants, "and should not be solely relied upon to provide
protection of our ground-water resources." The Agency recognizes
that rapidly migrating contaminants could be missed by soil monitoring.
Recently, researchers at Texas A&M have discovered that organic
compounds migrated through field tests plots at a rate that was three
times faster than water.14 The waste applied to the test plots was
API separator sludge and is commonly land treated at many oil
refineries.
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Additional impetus for ground-water monitoring came indirectly
from the commenters who were dissatisfied with the Agency's
interpretation of what constituted contamination. The regulations
required remedial measures if contaminants migrated to three times
the depth of the zone of incorporation. This facet of soil
monitoring, which will be discussed in detail later, was considered
to be arbitrary and precluded using the full capacity of the soil
to attenuate waste. Ground-water monitoring, as required for
landfills and surface impoundments, would provide a more consistent
and clear determination of environmental impact at land treatment
facilities.
Given the concern over the limitations of soil monitoring and
the claim that the Agency's interpretation of contamination is
arbitrary, ground-water monitoring is now required at land treatment
facilities during interim status. The requirements are the same as
for surface impoundments or landfills.
Besides the issues raised in the comments the Agency is
requiring ground-water monitoring for three reasons. First, many
of the land treatment facilities covered under interim status have
not operated under the philosophy of "limited waste migration."
Contaminants at these sites are likely to have already migrated
beyond three times the depth of the zone of incorporation. Soil
monitoring, as proposed, would provide no information on the depth,
concentration, or type of contaminants that have migrated beyond
the depth to which soil cores are taken. Second, at existing
facilities new unsaturated zone monitoring (both soil and soil-pore
water monitoring) is not reliable in indicating if contaminants have
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already migrated to ground water and what impact they may have on
ground water. The only sure way to know at existing facilities is
to monitor ground water. Third, soil monitoring will be used as an
indicator of how well the treatment process is working. As a
result, the soil monitoring requirements have been modified to
provide more flexibility than the proposed regulations. These
changes and the rationale for them are discussed below.
2. Soil Monitoring
Responses to the comments on the proposed soil monitoring
regulations are discussed collectively to facilitate presentation
of the revised monitoring scheme for land treatment facilities.
One of the most prevalent points made by commenters was that
the sampling frequency should be other than one core per acre.
Most of the commenters felt that the one soil core per acre
requirement was excessive and the cost exorbitant. Several
alternative sampling schemes were suggested, including:
0 The number of soil cores should be variable until more
research can be performed.
•X
0 A minimum of 10 cores and not less than one core per acre
should be required, regardless of site size.
0 An incentive to take more than one core per acre could be
provided by making what constitutes a significant increase,
a function of sample size, i.e., if one core per acre is
taken, then an increase in the level of a contaminant of
1.2 times background would be considered a significant
increase: if two cores per acre were taken, then a significant
increase would be 1.4 times background, etc.
0 For landfarms of 50 acres or less, take one core near each
corner of the site and one from the center.
0 Take one soil core per 10 acres, but not less than one soil
core per treated area.
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0 The number of soil cores taken per acre should be a function
of landfarm size, e.g.,:
Landfarm Size (in acres) Core Per Unit Area
5 1 core/acre
6-9 1 core/1.5 acres
10-30 1 core/2 acres
31-60 1 core/3 acres
>60 1 core/4 acres
0 Allow compositing of samples taken at one core per acre in
areas where only one type of waste or waste mix is applied
at a uniform rate.
Each of the above proposed sampling schemes, as well as the
approach proposed in the regulations, is deficient in not being
linked to a test of statistical significance for comparison with
background levels. The Agency felt that the soil monitoring scheme
had to have a statistical basis since it was a regulatory tool used
in determining if punitive action would be taken against a facility.
Because of the Agency' s decision to require ground-water monitoring
at land treatment facilities, soil monitoring will not play a
punitive role during interim status. Soil monitoring will still be
required, however, it will be structured differently and will be
used to determine the effectiveness of the land treatment process.
Commenters suggested analyzing for tracers or indicator
substances, rather than for the broader range of hazardous components
that could be in a waste. Cost was cited as a reason for this
suggestion. Lack of sufficient analytical capacity and procedures
was also mentioned. It was suggested that due to waste degradation,
the form of chemical components might change, making it uncertain
what actual hazardous constituents were present.
The Ajency does not agree that there is a lack of analytical
capacity of procedures to carry out a comprehensive analysis. No
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evidence was presented to support that contention, and the experience
of the Agency strongly suggests that this is not the case.
The point about waste degradation may well be valid particularly
regarding organic wastes. Ideally, one would have sufficient data
on land treatment to predict the degradation products and include
them in the waste analysis. Unfortunately, such data is not
available, but the revised soil analysis requirements should begin
to develop such information. Some predictions of degradation
products possibly could be made during the permit process on a case-
by-case basis. However, during the interim status period, such
interaction is not possible. Thus, for interim status, the Agency
sees no reasonable solution to the problem of degradation products.
Use of indicator substances does have merit from a cost and
t
simplicity standpoint. Conceptually, if one could select a substance
in the waste which was known to migrate in the soil at least as
rapidly as any other substances in the waste, then it could be
monitored as an indicator. If that substance was detected as having
migrated, then a more comprehensive analysis for other substances
should be carried out.
However, the Agency has decided not to allow use of indicator
substances during interim status. One reason is that the Agency
has not yet been able to devise a set of indicator substances that
reflect the success of waste treatment in the soil. During the
permitting process, an owner or operator could present data to the
Agency supporting a particular indicator for a particular situation.
However, this interaction is not possible during interim status.
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The second major reason for rejecting indicator substances is
that in order to specify proper permit conditions, the Agency needs
the information which would come from a more comprehensive analysis.
One of the major difficulties with developing land treatment
regulations is that it is a relatively new waste management process,
and there is limited data on the manner in which waste so treated
is rendered safe to human health and the environment. Thus,
knowledge of how all of the hazardous constituents in the waste are
moving in the soil is important to the coming permitting process.
It is possible that the information gathered by the time the permit
is to be issued will support the use of one or more indicator
substances. The Agency believes that the constituents to be
monitored under §265.273 are sufficiently few as not to cause undue
burden.
The issues of soil-core depth and corrective action are
.discussed together since they are closely related. The regulations
proposed that soil cores be taken to a depth of three times the
zone of incorporation. If migration of contaminants was detected,
as indicated by an increase in waste constituents over background
levels in the bottom one-third of the core, then the owner or operator
was to cease operation in the affected area, notify the Regional
Administrator, and determine corrective action.
Some commenters objected to the monitoring depth of three
times the zone of incorporation as being less desirable than a
fixed core depth. Three feet was suggested. It was argued that
depth of tillage was not relevant in determining environmental
performance. In contrast, several commenters felt the support for
the proposed monitoring depth was appropriate.
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The proposed monitoring depth was critized for the corrective
action required if migration to that depth occurred. Commenters
argued that the fact that migration to the specified depth had
occurred was not an indication of actual or potential environmental
damage, and that the corrective action proposed was overly stringent
and unjustified.
In consideration of the comments received on soil monitoring,
and upon further analysis of the alternatives available the Agency
has revised its approach to monitoring the environmental performance
of land treatment facilities. The environmentally sensitive nature
of land treatment requires the owner or operator to have an accurate
picture of the treatment process at work in the soil. EPA has
decided that such an objective requires a more comprehensive monitoring
plan than was proposed. Consequently, the new monitoring plan will
be more comprehensive than previously proposed. The plan will
require soil monitoring/ using soil cores, and in addition, the
owner or operator will be required to monitor the soil-pore water,
using lysimeters or similar devices. This new monitoring scheme,
now called "unsaturated zone (zone of aeration)" monitoring, although
requiring an additional type of monitoring, is structured so that it
will provide the owner or operator with the flexibility necessary
to develop a site-specific monitoring plan.
Although lysimeter monitoring was not proposed, it is necessary,
because, as commenters pointed out, soil monitoring will not detect
rapidly migrating waste constituents. Given the comments on
contaminant migration, and indications from an EPA-sponsored study
that some organic compounds are apparently capable of rapid
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migration1^, it is evident that soil monitoring may not adequately
detect contaminant migration and that soil-pore water monitoring
may also be needed. The need for more comprehensive monitoring is
further justified by the fact that land treatment facilities
characteristically lack liners.
Unlike landfills and surface impoundments the use of lysimeters
or similar devices is feasible at land treatment sites. Lysimeters
can be installed at land treatment facilities in the area where
waste has been applied. This is not practical for existing surface
impoundments and landfills. In addition, the relatively shallow
depth of waste application at land treatment facilities permits
lysimeters to be replaced at both existing and new facilities, when
they become clogged or otherwise nonfunctional. Furthermore, land
treatment facilities do not have artificial liners which would
interfere with the placement of lysimeters. The advantage of
monitoring soil-pore water is that this type of monitoring will detect
contaminants passing through the soil, whereas soil monitoring does
not detect what passes through, but what has been left behind. The
timing of soil-pore water sampling is very important. The sample(s)
must be taken when soil-pore water from waste application is present
in the sampling device. This is a function of when the waste is
applied, the water content of the waste, precipitation, soil
permeability, and depth of the lysimeter.
Soil-pore water monitoring in combination with soil and ground-
water monitoring will provide comprehensive knowledge about the
performance of the facility and its ability to protect ground water.
This monitoring approach will also provide information on the mass
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balance (i.e., location, distribution, concentration) of contaminants
in the soil system. This type of information is not only necessary
from a regulatory (environmental performance) standpoint, but is
requisite to understanding how a land treatment system functions.
Using the monitoring data as feedback on the performance of a site,
an owner or operator can more effectively manipulate operating variables
in order to optimize the performance of the site (e.g., waste
application rates, tilling frequency, and pH controls).
The regulations for unsaturated zone monitoring are structured,
as discussed previously, to provide the owner or operator with the
flexibility necessary to design a monitoring program which takes
into account site-specific factors. The regulation includes a list
of factors and relationships that must be taken into account when
developing the plan. The owner or operator must maintain all data
collected and make it available for review upon request by the
Regional Administrator, and must submit all the data in conjunction
with Part B of the application for a permit in accordance with
Section 122, Subparts A and B. The unsaturated zone monitoring
information will be particularly useful in developing the closure
and post-closure care plans. This approach is intended to accommodate
inherent differences between sites, and stimulate innovation of
more efficient monitoring methods and plans.
3. Summary
The Agency has revised the monitoring requirements at
hazardous waste land treatment facilities. Because of concerns
raised by some commenters over the inability of soil monitoring to
detect highly mobile contaminants, the Agency decided to require
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ground-water monitoring at land treatment facilities. Further
impetus for ground-water monitoring came from a need for a more
clear determination of what constitutes contamination at a land
treatment facility. Additionally, the Agency needed a mechanism
for evaluating the total impact that interim status land treatment
facilities had on the environment. This evaluation was considered
necessary in light of the fact that most land treatment facilities
have not operated under the previously proposed philosophy of
limited waste migration.
Significant changes were made to the proposed soil monitoring
regulations in response to both public and in-house comments. The
proposed soil monitoring scheme has been replaced with a more
comprehensive unsaturated zone monitoring scheme. Soil-pore water
monitoring, using lysimeters or similar devices is required in
addition to soil monitoring. Although the new scheme is more
comprehensive than the pro.posed regulations, it is structured to giv«
the owner or operator the flexibility necessary to develop a site-
specific monitoring plan.
D. Final Regulatory Language
§265.278 Unsaturated Zone (zone of aeration) Monitoring
[Interim Final]
(a) The owner or operator must have in writing, and must
p.
implement/ an unsaturated zone monitoring plan which is designed
to:
(1) Detect the vertical migration of hazardous waste and
hazardous waste constituents under the active portion of the land
treatment facility, and
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(2) Provide information on the background concentrations of
the hazardous waste and hazardous waste constituents in similar but
untreated soils nearby; this background monitoring must be conducted
before or in conjunction with the monitoring required under paragraph
(a)(1) of this Section.
(b) The unsaturated zone monitoring plan must include, at a
minimum:
(1) Soil monitoring using soil cores, and
(2) Soil-pore water monitoring using devices such as lysimeters.
(c) To comply with paragraph (a) (1) of this Section, the
owner or operator must demonstrate in his unsaturated zone monitoring
plan that:
(1) The depth at which soil and soil-pore water samples are to
be taken is below the depth to which the waste is incorporated into
the soil;
(2) The number of soil and soil-pore water samples to be
taken is based on the variability of:
(i) The hazardous waste constituents (as identified in §265.273(a)
and (b) in the waste and in the soil; and
(ii) The soil types(s); and
(3) The frequency and timing of soil and soil-pore water
sampling is based on the frequency, time, and rate of waste
application, proximity to ground water, and soil permeability.
(d) The owner or operator must keep at the facility his
unsaturated zone monitoring plan, and the rationale used in developing
this plan.
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(e) The owner or operator must analyze the soil and soil-pore
water samples for the hazardous waste constituents that were found
in the waste during the waste analysis under §265.273 (a) and (b).
[Comment; As required by §265.73, all data and information developed
by the owner or operator under this Section must be placed in the
operating record of the facility.]
5. Issue; Recordkeeping and reporting
A. Proposed Regulations and Rationale
The proposed regulations included in §250.45-5, recordkeeping
and reporting requirements, are applicable to all treatment, storage,
and disposal facilities, including land treatment.• The requirements
included: an operating log, a record of the quantity and description
of each waste received, locations in the facility where each waste
was treated or disposed and methods and dates of treatment or
disposal, the results of the waste analysis performed, monitoring
data, reports of visual inspections, and records of incidents
requiring initiation of a contingency plan.
The rationale for these requirements is presented in the
background document dealing with the manifest, recordkeeping, and
reporting requirements of the interim status regulations.
B. Comments/Respoonse to Comments
Comments on the proposed recordkeeping and reporting
requirements are discussed in the background document on Manifest
System, Recordkeeping and Reporting. In structuring the final
interim status regulations, the Agency has elected to include some
of the proposed recordkeeping requirements in the sections of the
regulations which address specific types of facilities. Such
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recordkeeping is needed to allow the owner or operator and the
Regional Administrator to evaluate the facility's compliance with
other requirements of the land treatment Subpart.
For land treatment facilities, recordkeeping requirements have
been incorporated relative to the location where each different
waste is placed in the facility, when it was placed there, and at
what rate. This information will assist, through the use of mass-
balance analysis, in determining whether the treatment objective of
the facility is being met. The Agency believes that these requirements
are an integral part of facility oprations. These records may be
needed to assist the owner or operator in emergency situations or
enforcement officials who may be called upon to investigate problems.
In most cases such recordkeeping will be routinely performed to
satisfy or supplement monitoring and closure requirements.
The recordkeeping requirements for land treatment facilities
are not expected to be burdensome since the types of waste and
treatment areas are typically limited at any one land treatment
facility.
Additional recordkeeping requirements relative to results
obtained from unsaturated zone monitoring, food-chain crop testing
or monitoring, and monitoring or analysis carried out under the
closure plan are specified in comments following certain of the
land treatment regulations. The owner or operator is required to
*
place the data and information in the operating record of the
facility. A discussion of the facility operating record and the
rationale for the inclusion of the data and information specified
in the comments following some of the land treatment regulations
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is discussed in the background document on Manifest System,
Recordkeeping/ and Reporting.
C.- Final Regulatory Language
§265.279 Recordkeeping
The owner or operator of a land treatment facility must
keep records of the application dates, application rates, quantities,
and location of each hazardous waste placed in the facility, in the
operating required in §265.73.
6. Issue; Closure
A. Proposed Interim Status Regulations and Rationale
The proposed regulations provided two basic options for
closure of a land treatment facility. One option was to return the
soil in the treated area to its prexisting condition, as determined
by background soil analysis or analysis of similar local soils.
The other option was to remove the contaminated soil from the
facility if that soil met the characteristics of a hazardous waste.
(If it did not fail the hazardous waste characteristics, no further
action was required.) However, a variance to the second option
provided an option to close the facility as a landfill if the owner
or operator could demonstrate that the design or location provided
long-term integrity and environmental protection equivalent to a
landfill, as specified in the proposed regulations.
One objective of the requirement to return the soil to its
preexisting condition or remove it, was to prevent the conversion
of huge tracts of productive land to land having limited potential
for future use. In addition, the Agency has limited data on the
fate and long-term effects of the hazardous contaminants in a land
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treatment facility. There was concern that the contaminants would
eventually be carried away by surface runoff or would migrate to
ground water.
There was some precedent in state regulations for the proposed
approach. The Texas Department of Natural Resources incorporates a
similar approach in some of the permits issued for land treatment
facilities. If the results of tests comparing the leachate from
treated soil with untreated soil suggest a potential threat of
hazard to surface water/ the Texas DNR requires the removal of soil
to a depth of 12 inches.
The variance for closure as a landfill was based on the
assumption that if appropriate liners, monitoring/ and cover were
provided, the facility would not present a significant potential
for environmental damage. While this and the other closure options
take a conservative posture on closure, the Agency felt that it had
no information to suggest that other approaches would be protective.
This is due to the fact that/ to the knowledge of EPA, no hazardous
land treatment facility has been closed to date.
B. Comments on the Proposed Regulations
1. Return of Soil to Original Condition
0 Requiring return of soil to its original condition is
beyond RCRA authroity. There is nothing in RCRA or its
legislative history to support this requirement.
0 Land treatment may improve some soils/ so return to original
condition would be considered counterproductive.
0 Requiring that land be returned to its original condition
is unreasonable, impractical, and prohibitivly expensive
and will eliminate land treatment.
0 The regulations should consider return to productive use,
i.e., capable of supporting indigenous vegetation.
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0 The term "preexisting conditions" is vague and indefinite,
and the regulations fail to establish standards by which
the condition of the land upon closure may be established.
0 Return to original soil condition is unnecessary because
land treatment facilities can be returned to productive use
as long as levels of contaminants in the soil are not a
problem for those uses, and the amount of land used or
contemplated is not a significant portion of productive land
e Requiring return of the soil to its preexisting condition
discriminates against industry, since land treatment of
POTW sludges has no such restrictions.
2. Use of the Extraction Procedure* (EP) on Soil
0 The EP may not appropriately identify contaminated soil.
It will underestimate the contamination of the soil, since
it does not test for all hazardous contaminants, only those
in the EPA Drinking Water Standards .
0 The dcecision to remove soil should include factors such
as: the chemical and physical characteristics of the
contaminants, the soil's ability to support vegetation,
the potential for erosion, the site location, and the
intended future use of the land.
0 The EP is not appropriate for clay soils, which often
contain cadmium and selenium in their natural state. Thus,
the EP may show virgin soil to be hazardous.
Should use water rather than the acid in the soil EP
because water is the "natural leachant" from precipitation
and runoff.
0 Naturally-occurring soils would fail the EP (data not
provided) .
3. Soil Removal; Closure as a Landfill
0 The potential expense of removal of soil or closure as a
landfill is extreme and would create a serious threat to
land treatment of industrial wastes.
0 To remove and landfill the soil in a land treatment facility
would so increase the overall cost of land treatment that
it would become economically noncompetitive with a landfill
or other disposal options. This would eliminate land
treatment as a disposal method. (No data provided.)
*The Extraction Procedure is described i §250.13(d) of Subpart A
in the December 19, 1978, proposed regulations.
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The removal of soil can result in problems of accelerated
erosion that would negate any questionable advantage of
removal.
Suggested Alternative Closure Requirements
Soil should be allowed to remain only when soil erosion is
negligible for 50 to 100 years and an impermeable soil
structure exists.
Closure regulations should specify the objective of closure,
when it should begin, and certain minimum conditions.
Determination of when closure should begin should be basad
on waste characteristics and soil properties, particularly
assimilation capacity. It is recommended that closure
regulations require:
- closure so that no further maintenance is necessary
- treating the soil to achieve a pH of 6.5 (minimum)
- vegetable cover
- control of erosion; maintenance of dikes
- removal of any soil incapable of supporting vegetation or
which presents a threat to human health and the environment
Should consider specifying pH maintenance and other "onsite"
measures to prevent migration.
Should require only soil monitoring for closure because
return to original condition is too difficult, and removal
would not eliminate the disposal problem. Additional
protection could be provided by the type of soil and the
berm around the treated area.
Should not look at the increase of contaminants in the
soil, but whether the soil presents a hazard to ground
water or whether crops grown on the soil would have
dangerously elevated concentrations.
Closure should relate to the level of potential environmental
harm.
Closure should require prevention of escape of absorbed
metals by runoff, plant uptake, or wind.
Should leave closure desig'n criteria to the owner/operator,
since proper design is site-specific.
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0 It is not true that, left unattended, contaminants of the
soil filter media will eventually be carried off by surface
runoff or will migrate to ground water. It is also not
true that such occurrences will be significant, especially if
plant cover is established. Under some conditions, soil
should be left as it is.
0 EPA's position for soil removal is inconsistent since EPA
admits no documented cases of ground-water contamination,
yet says that if soil is left unattended, contaminants
will eventually migrate.
C. Response to the Comments
1. Return of Soil to Preexisting Condition
The Agency agrees with may of the points made by commenters
and has removed this requirement from the final regulations. There
was a stong consensus in the comments that such a requirement was
impractical and would effectively terminate land treatment as a
waste management option. Furthermore, the Agency was unable to
identify methods of returning soil to its preexisting condition, or
to adequately define how the Agency would judge whether this has
been achieved. The Agency also concluded that this was not a
necessary condition for future productive use of the land. Finally,
and most importantly, the Agency believes that alternative closure
requirements which are more practical can achieve protection of the
environment.
2. Use of the Extraction Procedure (EP)
The proposed regulations referred to the extraction
procedure (EP), defined in Subpart A of the proposed regulations,
as the method to determine if soils in a land treatment facility
are hazardous at the time of closure. If the EP showed the soil to
be hazardous then the owner or operator was to close the site by
either removing the contaminated soil or closing the site as a landfill
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Comments on the use of the EP suggested it was inappropriate,
but for diametrically opposite reasons. Some commenters felt the
EP would underestimate contamination because it covered only a few
contaminants, while other commenters felt the EP would overestimate
the contamination of the soil because it was to harsh on extractant.
Two commenters expressed concern that the EP would show certain
virgin soils to be hazardous. No data was provided to corroborate
the comments.
Based upon the comments and a reevaluation of its position,
the Agency found that the EP, as proposed in Subpart A, is not
appropriate as the sole indicator of whether the soil should be
removed or the facility closed like a landfill.
The Agency considered altenative soil tests, but was unable to
identify any which had both broad application and the ability to
unequivocally indicate that the soil of a land treatment facility is
contaminated to the extent it would need to be removed.
The major drawback of using a simple soil test is that it does
not take into account the various extrinsic factors that play an
integral role in determining the hazard posed by the soil. This part
was made in the comments. One commenter suggested that the decision
to remove the soil of a land treatment facility should include
factors other than the EP results. The following factors were
i
idenrified: chemical and physical characteristics of the contaminants,
the soil's ability to support vegetation, the potential to support
vegetation, the potential for erosion, site location, and intended
future use of the land.
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The Agency has decided to use an approach similar to the one
suggested in the comments. The Agency has identified four
environmental objectives and a number of factors that the owner or
operator of a land treatment facility should consider to meet the
objectives, when deciding on the disposition of the soil from the
active portion(s) of the site. A detailed discussion is presented
below.
3. Waste Removal; Closure as a Landfill
Although most of the closure comments focused on return of the
soil to its preexisting condition, a few comments addressed waste
removal and closure as a landfill. The tenor of these comments
was that these requirements would be too costly and would make land
treatment noncompetitive. No data were provided to support these
claims.
The Agency agrees that these proposed closure options will
result in increased costs for land treatment. However, the conten-
tion that land treatment will become noncompetitive as a result of
cost is not tenable. The cost of all waste management practices
will increase as a result of the Subtitle C regulations, and the
Agency expects land treatment to remain a viable waste management
otion for certain waste streams. Additionally, it is not the
objective of the closure regulations to ensure that land treatment
remains competitive, in the economic sense. Rather, the objective
is to ensure that the closure requirements prevent the dispersion
of contaminants into the environment.
The real issue is whether there is a need for such a restrictive
approach. Because of the dearth of information available on closing
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land treatment facilities, and the relatively young age of this
waste managment practice, the Agency has not been able to unequivocably
demonstrate the need for such a restrictive and rigid closure
approach. As a result, the Agency has removed these closure
requirements from the final regulations in favor of a more flexible
approach, described below.
4. Alternative Closure Approaches
A number of alternative closure approaches were suggested
in the comments. Many of these approaches may have merit in a
given situation. Most depend on a case-by-case assessment.
The Agency believes that it is both feasible and desirable to
base the closure requirements on such individual assessments. The
owner or operator should be allowed to make a case that a given
*
closure procedure will suit his particular situation and provide
*
adequate environmental protection. This type of approach is necessary
because of the current lack of experience with land-treatment
closure and the consequent lack of a data base to adequately support
particular closure requirements.
Therefore, the Agency has substantially revised the closure
requirements for land treatment facilities. The new requirements
specify that the owner or operator must develop and implement a
facility closure plan. The terms of that plan are enforceable
against the owner or operator. The plan must address four objectives:
(1) controlling the migration of hazardous waste and hazardous
waste constituents into ground water; (2) controlling the release
of contaminated runoff to surface water; (3) controlling the release
of airborne particulate contaminants; and (4) compliance with the
standards established for food-chain crops. In meeting these
93
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objectives the owner or operator must consider a range of factors
affecting th facility's ability to meet the objectives. Relative
to ground-water protection/ these factors include: depth to ground
water; ground-water use; geological profile; amount and pH of
precipitation; type, concentration, and extent of migration of
contaminants in the soil; expected rate of contaminant migration
including any data from laboratory leaching studies using the soil
in the facility; soil characteristics, including cation exchange
capacity, total organic carbon, and pH; feasibility of removing the
contaminated soil at a later time if migration continues and appears
like to contaminant ground water; comprehensiveness of proposed
monitoring following closure; and proposed post-closure care,
including maintenance of unsaturated zone monitoring, restricting
site access, and future land use.
Relative to surface water protection, the factors include:
surrounding geography and land use, surrounding surface water uses
and quality, amount and pH of rainfall, use of cover or vegetation
to minimize erosion of contaminated soil, maintenance of diversion
structures to prevent surface runoff from entering the active
portion( s), facilities for collecting and treating any runoff, etc.
Regarding wind erosion, the Regional Admnistrator will evaluate
the use of vegetation or cover to prevent soil erosion and control
the release of airborne particulate contaminants.
The owner or operator must also develop a post-closure care plan
The terms of this plan are also enforceable against the owner or
operator. Under these interim status regulations the post-closure
care plan must provide for maintenance of monitoring systems,
94
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restriction of access as appropriate for post-closure use, and
control of the growth of food-chain crops to the same degree as
required for an active facility.
D. Final Regulatory Language
§ 265.280 Closure and post-closure [Interim Final]
(a) In the closure plan under §265.112 and the post-closure
plan under §265.118, the owner or operator must address the following
objectives and indicate how they will be achieved:
(1) Control, of the migration of hazardous waste and hazardous
waste constituents from the treated area into the ground water;
(2) Control of the release of contamnated run-off from the
facility into surface water;
(3) Control of the release of, airborne particulate contaminants
caused by wind erosion; and
(4) Complaince with §265.276 concerning the growth of food-
chain crops.
(b) The owner or operator must consider at least the following
factors in addressing the closure and post-closure care objectives
of paragraph (a) of this Section:
(1) Type and amount of hazardous waste and hazardous waste
constituents applied to the land treatment facility;
(2) The mobility and the expected rate of migration of the
hazardous waste and hazardous waste constituents;
(3) Site location, topography, and surrounding land use, with
respect to the potential effects of pollutant migration (e.g.,
proximity to ground water, surface water and drinking water sources);
(4) Climate, including amount, frequency, and pH of
95
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precipitation;
(5) Geological and soil profiles and surface and subsurface
hydrology of the site, and soil characteristics, including cation
exchange capacity, total organic carbon, and pH;
(6) Unsaturated zone monitoring information obtained under
§265.278; and
(7) Type, concentration, and depth of migration of hazardous
waste constituents in the soil as compared to their background
concentrations.
(c) The owner or operator must consider at least the following
methods in addressing the closure and post-closure care objectives
of paragraph (a) of this Section:
(1) Removal of contaminated soils
(2) Placement of a final cover, considering:
(i) Functions of the cover (e.g., infiltration control, erosion
and runoff control, and wind erosion control), and
(ii) Characteristics of the cover.- including material, final
surface contours, thickness, porosity and permeability, slope,
length of run of slope, and type of vegetation on the cover;
(3) Collection and treatment of runoff;
(4) Diversion structures to prevent surface water runon from
entering the treated area; and
(5) Monitoring of soil, soil-pore water, and ground water.
(d) In addition to the requirements of §265.117, during the
post-closure care period, the owner or operator of a land treatment
facility must:
(1) Maintain any unsaturated zone monitoring system, and
96
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collect and analyze samples,from this system in a manner and
frequency specified in the post-closure plan;
(2) Restrict access to the facility as appropriate for its
post-closure use; and
(3) Assure that growth of food-chain crops complies with
§265.276.
7. Issue; Special Requirements for Ignitable, Reactive and
Incompatible Wastes
A. Proposed Regulations and Rationale
The proposed regulations prohibited placing ignitable,
reactive, volatile, and incompatible wastes in a land treatment
facility, but allowed a variance if the owner or operator could
demonstrate that airborne contaminants would not exceed a specified
concentration, and that the attenuation capacity of the facility
would not be adversely affected through heat generation, fires,
or explosions.
This regulation, although not proposed as an interim status
standard, meets the criteria established by the Agency for interim
status standards.
The objective of the proposed regulation was to prevent damages
to human health and the environment which could result from fires
or explosions in a land treatment facility. Placing ignitable or
reactive wastes in a land treatment facility presents at least two
potential problems.
One problem is the contamination of the air through volatilization/
since most ignitable and some reactive wastes have relatively high
vapor pressures. A second problem is that ignitable and reactive
97
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wastes can explode or burn easily, injuring the personnel at the
facility and releasing toxic fumes that can reach surrounding
populations and cause personal and property damage. Fires and
explosions can also adversely affect the attentuation capacity of
the facility.
A recent study^ has shown that, during land treatment operations,
fires and explosions can occur. Potential ignition sources include
electrical sparks from machinery operating on the facility, accidents
or errors such as smoking near the facility, and extreme heat
generation from reactive or incompatible sources.
Mixing of hazardous wastes that ara not compatible with each
other in a hazardous waste land treatment facility can result in
similar types of environmental problems. Such mixing can cause
fires and explosions, excessive heat generation, or generation of
toxic gases. This could endanger facility personnel or populations
in the vicinity of the impoundment, or it could adversely affect
the attentuation capacity of the facility.
B. Comments on the Proposed Regulations
The restrictions on ignitable, reactive, and incompatible
wastes in the proposed regulations went beyond land treatment.
Similar restrictions were included in the proposed regulations for
all treatment and disposal facilities under §265.22, and standards
for basins under §250.45-5. The background documents dealing with
those standards contain additional analysis of comments on this issue.
Those comments directed specifically toward land treatment
facilities are as follows:
0 The restriction on ignitables should be revised to allow
land treatment if the waste is no longer ignitable after
incorporation into the soil.
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Many hazardous wastes classified as ignitable or reactive,
or which are incompatible when combined, may lose these
properties when mixed with the soil due to dilution,
absorption, or other mechanisms. Thus land treatment of
such wastes should not be prohibited.
0 A land treatment facility can act as a destruction mechanism,
rendering a waste nonhazardous through slow oxidation.
Ignitable, nitrated organics are particularly amenable to
slow oxidation in soils. This would be a safer disposal
method than rapid oxidation through incineration. The
hazard of most concern is placing the material without
incident during handling. An absolute prohibition against
land treatment of ignitables, reactives, or incompatibles
in any concentrations or quantities is inappropriate.
0 Land treatment is an attractive way to dispose of hazardous
oily wastes. The exclusion of land treatment of ignitables
should be lifted. This can be done safely with little or
no "fire hazard.
0 The proposed regulations will preclude land treatment as a
viable alternative, since many wastes are ignitable, reactive,
or volatile, and corrosive,wastes cannot be land treated
due to pH. The variance is not likely to be viewed favorably
by permit officials.
C. Response to the Comments
Relevant to the discussion of the comments above is the
fact that the Agency, in response to comments on the variance in
§250.45(c) dealing with volatility, has found it necessary to defer
any requirements relative to controls on volatiles. Similarly, the
variance in §250.45(c) regarding concentration of airborne contaminants
has been deferred and will be reconsidered when the Agency addresses
t
restrictions on volatile waste. The reader is referred to the
background document on tanks and basins for further discussion of
this issue.
The comments on ignitable waste suggest that incorporation of
such wastes into the soil is, in itself, an effective way of
rendering these wastes nonignitable. The flgency concurs with this
99
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suggestion. However, as a comment suggested, the safety of handling
the waste, i.e., incorporating it into the soil, is still an issue.
However, the Agency has no damage cases indicating that this has
been a problem in practice up to this time. Nevertheless, one way
of eliminating or reducing this handling hazard would be to treat
or mix the waste prior to land treatment, so that the resulting
material is no longer ignitable. This practice would provide the
greatest margin of safety.
A similar logic would apply to land treatment of reactive or
incompatible wastes. In an attempt to find a method of rendering
such wastes nonreactive, the Army Material Development Command, at
Bdgewood Aresenal in Natick, Massachusetts has safely land-treated
reactive wastes.^5 While other characteristics of the particular
waste, (i.e., nonbiodegradability), reduced the attractiveness of
land treatment, safe handling,- and rendering the wastes nonreactive
did seem possible.
In view of these considerations, the regulations have been
revised to include conditions under which such wastes can be land
treated.
D. Final Regulatory language
§265.281 Special requirements for ignitable or reactive waste
Ignitable or reactive wastes must not be land treated, unless
the waste is immediately incorporated into the soil so that (1) the
resulting waste, mixture, or dissolution of material no longer
meets the definition of ignitable or reactive waste under §§261.21
or 261.23 of this chapter, and (2) §265.17(b) is complied with.
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REFERENCES
1. TRW. Evaluation of Emission Control Criteria for Hazardous
Waste Management Facilities. Contract No. 68-01-4645, U.S.
Environmental Protection Agency, April 1978.
2. SCS Engineers. Land Cultivation of Industrial Wastes and Muni-
cipal Solid Wastes: State-of-the-Art Study. Volume Ie Con-
tract No. 68-03-2435, U.S. Environmental Protection Agency,
August 1978.
3. U.S. Environmental Protection Agency. Report to Congress:
Waste Oil Study. April 1974.
4. Hatayama, H.K., and D. Jenkins. *An Evaluation of the Weathering
Method of Disposal of Leaded Gasoline Storage Tank Wastes: A
Summary.* In: Proceedings of the National Conference about
Hazardous Waste Management, San Francisco, February 1-4, 1977.
In press.
5. Adriano, D.C., et alv 'Effect of Long-Term Land Disposal by
Spray Irrigation of Food Processing Wastes on Some Chemical
Properties of the Soil and Subsurface Water/* J. Environ. Qual.,
4:242-248, 1975.
6. Page, A.LV Fate and Effects of Trace Elements in Sewage Sludge
when Applied to Agricultural Lands. A Literature Review Study,
EPA-670/2-74-005, U.S. Environmental Protection Agency, January
1974.
7. Kincannon, C.B., Oily Waste Disposal by Soil Cultivation Pro-
cess, EPA-R2-72-100, U.S. Environmental Protection Agency,
December 1972.
8. Huddleston, R.L. "Treatment of Oily Wastes by Land Farming/
Presented at the RSMA Meeting, "Disposal of Industrial and Oily
Sludges by Land Cultivation," Houston, Texas, January 18-19,
1978.
9. Raymond, R.L., J.O. Hudson, and V.W. Jamison, "Assimilation of
Oil by Soil Bacteria" In: Proceedings of the 40th Midyear API
Meeting, 1975.
10. Telephone communication on November 11, 1979, with Mr. Bruce
Conrad, Division of Rights-of-Way, Bureau of Land Management,
Washington, D.C.
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11. Telephone communication on November 11, 1979, with Mr. Richard
Hopkins, Oil and Gas Surface Protection, Bureau of Land Manage-
ment, Cheyenne, Wyoming.
12. Telephone communication on November 11, 1979, with Mr. Lloyd
Fergeson, Bureau of Land Management, Salt Lake City, Utah. _
13. Meyers, J.D., and R.L. Huddleston, "Treatment of Oily Refinery
Wastes by Landfarming^' For presentation at the 34th Annual
Purdue Industrial Waste Conference, May 8-10, 1979.
14. Personnel communication with Dr. Kirk Brown, Texas A&M Uni-
versity, College Station, Texas, January 24, 1980.
15. Healy, W.3., Ingested Soil and Animal Nutrition? pp. 84-90. In
Proceedings of the New Zealand Grassland Association, 34, 1972.
16. Letter from R.L. Chaney, USDA Plant Physiologist, submitted to
EPA as comments on Proposed Criteria for Classification of Solid
Waste Disposal Facilities and Practices, May 12, 1978.
17. Jelinek, C.F., G.L. Brattde, and R.B. Read, Jr., "Management of
Sludge Use on Land, FDA Considerations '' presented at Association
of Metropolitan Sewerage Agencies Conference on Sludge Manage-
ment, Houston, Texas, April 13, 1976.
tr ^
18. Healy, W.B., Ingestion of Soil by Dairy Cows, New Zealand Jour-
nal of Agricultural Research, Vol. 11, No. 2, 1968, p. 498.
19. U.S. Environmental Protection Agency, Land Cultivation of Indus-
trial Wastes and Municipal Solid Wastes: State-of-the-Art
Study, Volume II, 1978, 157 p.
20. Bergh, A.K., and R.S. Peoples,"Distribution of Polychlorinated
Biphenyls in a Municipal Wastewater Treatment Plan and Environs,
The Science of the Total Environment, 1977.
21. Personal communication with Dr. P. Kearney, USDA, Beltsville,
Maryland.
22. Personal communication with Dr. A.M. Decker, University of
Maryland, College Park, Maryland.
23'. Harrison, D.L., J.C.M. Mol, and W.B. Healy. New Zealand Journal
of Agricultural Research, 13, pp. 664-672.
24. Personal communication with Dr. G. Fries, USDA, Beltsville,
Maryland.
103"
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25. Chaney, R.L., and P.M. Giordano. "Microelements as Related to
Plant Deficiencies and Toxicities," pp. 235-279. In L.F. Elliott
and F.J. Stevenson (ed.), Soils for Management of Organic Wastes
and Wastewaters. Soil Science Society of America, Madison,
Wisconsin, 1977.
26. Chaney, R.L., and C.A. Lloyd, Adherence of Spray-Applied,
Liquid, Digested Sewage Sludge to Tall Fescue," submitted to EPA
as comments on Proposed Criteria for Classification of Solid
Waste Disposal Facilities and Practices.
27. Jones, S.G., K.W. Brown, L.E. Deuel, and K.C. Donnelly, "influ-
ence of Simulated Rainfall on the Retention of Sludge Heavy
Metals by the Leaves of Forage Crops') Journal of Environmental
Quality5 Vol. 8, No. 1, 1979, p. 69.
28. Allaway. W.H., "Food Chain Aspects of the Use of Organic Resi-
dues" pp. 282-298. In L.F. Elliot and F.J. Stevenson (ed.),
Soils for Management of Organic Wastes and Wastewaters, Soil
Science Society of American, Madison, Wisconsin, 1977.
29. Kardos, L.T., C.E. Scarsbrook, and V.V. Volk, "Recycling Ele-
ments in Wastes through Soil - Plant Systems," pp. 300-324. In
L.F. Elliot and F.J. Stevenson (ed.), Soils for Management of
Organic Wastes and Wastewaters. Soil Science Society of America,
Madison, Wisconsin, 1977.
30. Kirkham, M.B.,"Trace Elements in Sludge on Land: Effect on
Plants, Soils, and Groundwater," pp. 209-247. In R.C. Loehr
(ed.), Laud as a Waste Management Alternative, Ann Arbor Science
Publishers, Inc., Ann Arbor, Michigan, 1977.
31. U.S. Environmental-Protection Agency, Reviews of the Environ-
mental Effects of Pollutants: VII Lead, 1979.
32. U.S. Environmental Protection Agency. Sludge Treatment and Dis-
posal, Volume 2, 1978, 155 p.
33. Pahren, H.R., J.B. Lucas, J.A. Ryan, and G.K. Dotson, An
Appraisal of the Relative Health Risks Associated with Land
Application of Municipal Sludge',' presented at 50th Annual Con-
ference of the Water Pollution Control Federation,, 1977.
34. Iwata, Y. et al. "Uptake of PCB (Aroclor 1254) from Soil by Car-
rots under Field Conditions* Bulletin of Environmental Contami-
nation and Toxicity, Volume 2, 1974.
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35. Personal communication. George Marienthal, Department of
Defense, Washington, D.C., to L.A.Weiner, Office of Solid
Waste. October 19, 1977.
36. Phung, H.T., D.E.Ross, and R. E. Landreth, 'Land Cultivation of
Industrial Wastewater and Sludges/1 Proc. National Conference
on Treatment and Disposal of Industrial Wastewaters and
Residues. 1977 (in press).
37. Raymond, R. L. , J. O. Hudson, and V.W. Jamison, "oil Degradation
in Soil/ Applied and Environmental Microbiology, 31:4, 522-535,
April 1976.
38. Elfuing, D.C., Hascheck, W.M., Stehn, R.A., Bache, C.A. and
Lisk, D.J., "Heavy Metal Residues in Plants Cultivated on and
in Small Mammals Indigenous to Old Orchard Soil/' Archives of
Enviromental Health, 33(2), 95-99 (1978).
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APPENDIX A
INTERIM STATUS STANDARDS
FOR LAND TREATMENT
-------
Subpart M - Land Treatment
§265.270 Applicability
The regulations in this Subpart apply to owners and oper-
ators of hazardous waste land treatment facilities, except as
§265.1 provides otherwise.
[§265.271 Reserved]
§265.272 General operating requirements [Interim Final]
(a) Hazardous waste must not be placed in or on a land
treatment facility unless the waste can be made less hazardous
or non-hazardous by biological degradation or chemical reactions
occurring in or on the soil.
(b) Run-on must be diverted away from the active portions
of a land treatment facility.
(c) Run-off from active portions of a land treatment facility
must be collected.
[Comment; If the collected run-off is a hazardous waste under
Part 261 of this Chapter/ it must be managed as a hazardous waste
in accordance with all applicable requirements of Parts 262, 263,
and 265 of this Chapter. If the collected run-off is discharged
through a point source to waters of the United States, it is
subject to the requirements of Section 402 of the Clean Water
Act, as amended.]
(d) The date for compliance with paragraphs (b) and (c)
of this Section is 12 months after the effective date of this
Part.
A-l
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§265.273 Waste analysis
In addition to the waste analyses required by §265.13,
before placing a hazardous waste in or on a land treatment facility,
the owner or operator must:
(a) Determine the concentrations in the waste of any sub-
stances which exceed the maximum concentrations contained in Table I
of §261.24 of this Chapter that cause a waste to exhibit the EP
toxicity characteristic;
(b) For any waste listed in Part 261, Subpart D, of this
Chapter, determine the concentrations of any substances which
caused the waste to be listed as a hazardous waste; and
(c) If food chain crops are grown, determine the concentra-
tions in the waste of each of the following constituents: arsenic,
cadmium, lead, and mercury, unless the owner or operator has
written, documented data that show that the constituent is not
present.
CComment; Part 261 of this Chapter specifies the substances for
which a waste is listed as a hazardous waste. As required by
§265.13, the waste analysis plan must include analyses needed to
comply with §§265.281 and 265.282. As required by §265.73, the
owner or operator must place the results from each waste analysis,
\
or the documented information, in the operating record of the
facility.]
[§265.274 Reserved]
[§265.275 Reserved]
§265.276 Food chain crops [Interim Final]
(a) An owner or operator of a hazardous waste land treatment
facility on which food chain crops are being grown, or have been
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grown and will be grown in the future, must notify the Regional
Administrator within 60 days after the effective date of this
Part.
CComment; The growth of food chain crops at a facility which has
never before been used for this purpose is a significant change
in process under §122.23(c)(3) of this Chapter. Owners or oper-
ators of such land treatment facilities who propose to grow food
chain crops after the effective date of this Part must comply
with §122.23(c)(3) of this Chapter-]
(b)(l) Food chain crops must not be grown on the treated
area of a hazardous waste land treatment facility unless the
owner or operator can demonstrate, based on field testing,
that any arsenic, lead, mercury, or other constituents
identified under §265.273(b):
(i) Will not be transferred to the food portion of the
crop by plant uptake or direct contact, and will not
otherwise be ingested by food chain animals (e.g., by
grazing); or
(ii) Will not occur in greater concentrations in the
crops grown on the land treatment facility than in the
same crops grown on untreated soils under similar
conditions in the same region.
(2) The information necessary to make the demonstration
required by paragraph (b)(1) of this Section must be kept at
the facility and must,-at a minimum:
(i) Be based on tests for the specific waste and
application rates being used at the facility; and
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(ii) Include descriptions of crop and soil character-
istics, sample selection criteria/ sample size deter-
mination, analytical methods, and statistical procedures.
(c) Food chain crops must not be grown on a land treatment
facility receiving waste that contains cadmium unless all require-
ments of paragraph (c)(l)(i) through (iii) of this Section or all
requirements of paragraph (c)(2)(i) through (iv) of this Section
are met.
(1) (i) The pH of the waste and soil mixture is 6.5 or greater
at the time of each waste application, except for waste
containing cadmium at concentrations of 2 mg/kg (dry
weight) or less;
(ii) The annual application of cadmium
from waste does, not exceed 0.5 kilograms per hectare
i
(kg/ha) on land used for production of tobacco, leafy
vegetables, or root crops grown for human consumption.
For other food chain crops, the annual cadmium application
rate does not exceed:
Annual Cd
Application Rate
Time Period (kg/ha)
Present to June 30, 1984 2.0
July 1, 1984 to Dec. 31, 1986 1.25
Beginning Jan. 1, 1987 0.5
(iii) The cumulative application of cadmium from waste
does not exceed the levels in either paragraph (c)(1)(iii)(A)
of this Section or paragraph (c)(1)(iii)(B) of this Section.
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(A)
Maximum cumulative application (kg/ha)
Soil cation
exchange capacity Background soil pH Background soil pH
(meq/lOOg) less than 6.5 greater than 6.5
less than 5 5 5
5-15 5 10
greater than 15 5 20
(B) For soils with a background pH of less than
6.5, the cumulative cadmium application rate
does not exceed the level s below: Provided, that
the pH of the waste and soil mixture is adjusted
to and maintained at 6.5 or greater whenever food
chain crops are grown.
Soil cation exchange capactiy Maximum cumulative
(meq/100g) application (kg/ha)
less than 5 5
5-15 10
greater than 15 20
(2) (i) The only food chain crop produced is animal feed.
(ii) The pH of the waste and soil mixture is 6.5 or
greater at the time of waste application or at the time
the crop is planted, whichever occurs later, and this
pH level is maintained whenever food chain crops are
grown.
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(iii) There is a facility operating plan which demon-
strates how the animal feed will be distributed to
preclude ingestion by humans. The facility operating
plan describes the measures to be taken to safeguard
against possible health hazards from cadmium entering
the food chain/ which may result from alternative land
uses.
(iv) Future property owners are notified by a stipu-
lation in the land record or property deed which states
that the property has received waste at high cadmium
application rates and that food chain crops should not
be grown/ due to a possible health hazard.
[Comment; As required by §265.73, if an owner or operator grows
food chain crops on his land treatment facility/ he must place
i
the information developed in this Section in the operating record
of the facility.]
[§265.277 Reserved]
§265.278 Unsaturated zone (zone of aeration) monitoring
[Interim Final]
(a) The owner or operator must have in writing, and must
implement, an unsaturated zone monitoring plan which is designed
to:
(1) Detect the vertical migration of hazardous waste
and hazardous waste constituents under the active portion of
the land treatment facility, and
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(2) Provide information on the background concentrations
of the hazardous waste and hazardous waste constituents in
similar but untreated soils nearby; this background monitoring
must be conducted before or in conjunction with the monitoring
required under paragraph (a)(l) of this Section.
(b) The unsaturated zone monitoring plan must include/ at
a minimum:
(1) Soil monitoring using soil cores, and
(2) Soil-pore water monitoring using devices such as
lysimeters.
(c) To comply with paragraph (a)(l) of this Section, the
owner or operator must demonstrate in his unsaturated zone mon-
itoring plan that:
(1) The depth at which soil and soil-pore water samples are
to be taken is below the depth to which the waste is
incorporated into the soil;
(2) The number of soil and soil-pore water samples to be
taken is based on the variability of:
(i) The hazardous waste constituents (as identified
in §265.273(a) and (b)) in the waste and in the soil;
and
(ii) The soil type(s); and
(3) The frequency and timing of soil and soil-pore water
sampling is based on the frequency, time, and rate of waste
application, proximity to ground water, and soil permeability.
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(d) The owner or operator must keep at the facility his
unsaturated zone monitoring plan, and the rationale used in
developing this plan.
(e) The owner or operator must analyze the soil and soil-
pore water samples for the hazardous waste constituents that
were found in the waste during the waste analysis under §265.273
(a) and (b).
[Comment; As required by §265.73, all data and information
developed by the owner or operator under this Section must be
placed in the operating record of the facility.]
§265.279 Recordkeeping
The owner or operator of a land treatment facility must keep
records of the application dates, application rates, quantities,
and location of each hazardous waste placed in the facility, in
the operating record required in §265.73.
§265.280 Closure' and post-closure [Interim Final]
(a) In the closure plan under §265.112 and the post-closure
plan under §265.118, the owner or operator must address the
following objectives and indicate how they will be achieved:
(1) Control of the migration of hazardous waste and
hazardous waste constituents from the treated area into
the ground water;
(2) Control of the release of contaminated run-off from
the facility into surface water;
(3) Control of the release of airborne particulate
contaminants caused by wind erosion; and
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(4) Compliance with §265.276 concerning the growth
of food-chain crops.
(b) The owner or operator must consider at least the following
factors in addressing the closure and post-closure care objectives
of paragraph (a) of this Section:
(1) Type and amount of hazardous waste and hazardous waste
constituents applied to the land treatment facility;
(2) The mobility and the expected rate of migration
of the hazardous waste and hazardous waste constituents ;
(3) Site location, topography, and surrounding land use,
with respect to the potential effects of pollutant
migration (e.g./ -proximity to ground water, surface water and
drinking water sources);
(4) Climate, including amount, frequency, and pH of
precipitation;
(5) Geological and soil profiles and surface and subsurface
hydrology of the site, and soil characteristics, including
cation exchange capacity, total organic carbon, and pH;
(6) Unsaturated zone monitoring information obtained
under §265.278; and
(7) Type, concentration, and depth of migration of hazardous
waste constituents in the soil as compared to their background
concentrations.
(c) The owner or operator must consider at least the following
methods in addressing the closure and post-closure care objectives
of paragraph (a) of this Section:
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(1) Removal of contaminated soils;
(2) Placement of a final cover, considering:
(i) Functions of the cover (e.g./ infiltration control,
erosion and run-off control, and wind erosion control), and
(ii) Characteristics of the cover, including material,
final surface contours, thickness, porosity and
permeability, slope, length of run of slope, and type
of vegetation on the cover;
(3) Collection and treatment of run-off;
(4) Diversion structures to prevent surface water run-on
from entering the treated area; and
(5) Monitoring of soil, soil-pore water, and ground water.
Cd) In addition to the requirements of §265.117, during
the post-closure care period, the owner or operator of a land
treatment facility must:
(1) Maintain any unsaturated zone monitoring system, and
collect and analyze samples from tVs system in a manner
and frequency specified in the post-closure plan;
(2) Restrict access to the facility as appropriate for its
post-closure use; and
(3) Assure that growth of food chain crops complies with
§265.276.
§265.281 Special requirements for ignitable or reactive waste*
Ignitable or reactive wastes must not be laad treated, unless
the waste is immediately incorporated into the soil so that (1)
the resulting waste, mixture, or dissolution of material no
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longer meets the definition of ignitable or reactive waste under
§§261.21 or 261.23 of this Chapter, and (2) §265.l7(b) is complied
with.
§265.282 Special requirements for incompatible "wastes*
Incompatible wastes, or incompatible wastes and materials,
(see Appendix V for examples) must not be placed in the same
land treatment area, unless §265.17(b) is complied with.
[§§265.283 - 265.299 Reserved}
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APPENDIX B
SUMMARY OF TEXAS AND OKLAHOMA
LAND CULTIVATION [TREATMENT] GUIDELINES
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APPENDIX B
SUMMARY OF TEXAS AND OKLAHOMA LAND CULTIVATION GUIDELINES
GUIDELINE (SUMMARY STATEMENT)
ITEM
TEXAS
OKLAHOMA
o Soils
w
i
o Topography
o Climate
o Surrounding Land Use
o Ground-water Conditions
o Should be deep, prefer high
clay and organic content and
have large surface area
(best soils are classed as CL,
OL, MI, C1I, and Oil under
the Unified Soil Classifica-
tion System)
o Prefer surface slopes less
than 5 percent, greater than
0 percent
o High net evaporation, median
mean temperature, moderate
24-hr, 25-yr frequency maxi-
mum rainfall
o Sparsely populated, or provide
buffer and locate downwind
from nearby residences
o Avoid shallow, potable ground
water. If not possible, pro-
vide vegetative cover, avoid
high application rates, moni-
tor ground water-quality
o Should be deep, have large
total surface area and have
high clay and organic content
(best soils are classed as CL,
OL, MI, CH, and OH under
the Unified Soil Classifica-
tion System)
o Slope should be less than 5
percent greater than 0 percent
o High net evaporation, median
mean temperature, moderate
24-hr, 50-yr frequency maxi-
mum rainfall
o Sparsely populated, or provide
buffer and locate downwind
from nearby residences
o Avoid shallow, potable ground
water. If not possible, pro-
vide vegetative cover, avoid
high application rates,
rigidly monitor ground-water
quality
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APPENDIX B (Continued)
GUIDELINE (SUMMARY STATEMENT)
ITEM
o Waste Restrictions
o Application Rates
w
i
to
TEXAS
OKLAHOMA
o Not addressed
o Minimum waste composition
analysis: Cl, PO/j, Total N,
Zn, Cu, Ni, As, Ba, Mn, Cr,
Cd, B, Pb, ilg, Se, Na, Mg, Ca
o Determine soil cati-on exchange
capacity (CEC)
o Total metals application over
site life should be less
than 50 percent of CEC of
top 1 ft of site's soil.
o If crop grown and harvested
at site, total metal appli-
cation in 30-yr period
should be less than 5 per-
cent of CEC.
o Water soluble, inorganic
industrial wastes should not
be land cultivated
o Minimum waste composition
analysis: Zn, Cu, Ni, As,
Ba, Mn, Cr, Cd, 0, Pb, Hg,
Se, Na, Mg, Ca, Cl, P04,
Total N
o Determine soil CEC if any of
the elements in waste composi-
tion analysis above are pre-
sent
o Not addressed
o Not addressed
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APPENDIX B (Continued)
GUIDELINE (SUMMARY STATEMENT)
ITEM
TEXAS
OKLAHOMA
o Application Kates
(concluded)
o Total N applied in waste, less
than 125 Ib/ac/yr
03
I
o Annual free water applied in
the waste should be less than
annual evaporation rate
o Not addressed
o Not addressed
o Total N applied in waste, no
more than 125 Ib/ac/yr, or the
maximum amount utilized or
assimilated by vegetative
cover
o Total free water applied should
be no more than the net evapor-
ation for time period between
applications
o Oily waste application rate
must be such that soil-waste
mixture contains no more than
10 percent oil by weight
o Recommended application rate
for oily wastes at established
(over 6 mo old) sites:
- 35 bbl oil/ac/mo—without
fertilizer
- 60 bbl oil/ac/mo—with
fertilizer
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APPENDIX B (Concluded)
GUIDELINE (SUMMARY STATEMENT)
ITEM
TEXAS
OKLAHOMA
o Operational
Restrictions
o Mixing Frequency
o Mixing Depth
o All runoff must be contained
(use dikes or lined control
collection basin) unless dis-
* charge permit is obtained.
Collection basin should con-
tain 25-yr> 24-hr maximum
rainfall
o Soil pll must be maintained at
above 6.5 while the site is
active
o Mix waste into soil as soon
as possible
o Vegetation for human or animal
consumption must be analyzed
for metals contained in the
waste before feeding.
o Not addressed
o Not addressed
o All runoff must be contained
unless discharge permit is
obtained (use dikes or lined
central collection basin)*
Collection basir must contain
all site runoff from a 50-yr,
24-hr maximum rainfall
/
o Soil pll must be maintained at
above 6.5 whi'e site is active
o Mix waste into soil as soon
as possible
o Vegetation for human or animal
consumption must be analyzed
for metals and any elements in
the waste which are known to be
concentrated'by the plant spe-
cies before use or sale
o Dependent on rainfall. Recom-
mended practice is to mix twice
monthly for first 2 months,
then once every other month
o Sludge should be mixed into
soil to a depth of 6 to 12 in.
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