Environmental Protection: Interim Actions to Better Control Cement Kiln
Dust (Letter Report, 08/14/95, GAO/RCED-95-192).
Pursuant to a congressional request, GAO reviewed the Environmental
Protection Agency's (EPA) decision-making process with respect to
regulating cement kiln dust, focusing on: (1) EPA priorities in making
its kiln dust determination; (2) whether EPA is authorized to modify
hazardous waste management requirements in regulating cement kiln dust;
(3) whether EPA believes that cement kilns burning hazardous waste
should be regulated the same as those not burning hazardous waste; and
(4) whether interim actions can be taken to control cement kiln dust.
GAO found that EPA: (1) does not give as high a priority to making a
cement kiln dust determination as developing standards for other wastes
considered to be of higher risk; (2) has the statutory authority to
modify its hazardous waste regulations to control cement kiln dust as
long as the regulations adequately protect human health and the
environment; (3) believes that cement kiln dust from both kilns could
adversely affect human health and the environment, if improperly
managed; (4) has not yet determined whether it will subject the dust
from the two types of kilns to the same regulations; and (5) is
considering interim actions to control cement kiln dust, such as making
greater use of existing regulatory authority to enforce current controls
over the dust and entering into an agreement with the cement kiln
industry to impose additional controls over the dust.
--------------------------- Indexing Terms -----------------------------
REPORTNUM: RCED-95-192
TITLE: Environmental Protection: Interim Actions to Better Control
Cement Kiln Dust
DATE: 08/14/95
SUBJECT: Toxic substances
Hazardous substances
Environmental monitoring
Air pollution control
Health hazards
Environmental policies
Regulatory agencies
Pollution monitoring
Waste management
Prioritizing
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Cover
================================================================ COVER
Report to the Chairman, Committee on Governmental Affairs, U.S.
Senate
August 1995
ENVIRONMENTAL PROTECTION - INTERIM
ACTIONS TO BETTER CONTROL CEMENT
KILN DUST
GAO/RCED-95-192
Interim Actions to Better Manage Cement Kiln Dust
Abbreviations
=============================================================== ABBREV
EPA -
RCRA -
CERCLA -
Letter
=============================================================== LETTER
B-261368
August 14, 1995
The Honorable William V. Roth, Jr.
Chairman, Committee on Governmental
Affairs
United States Senate
Dear Mr. Chairman:
Cement kilns use large amounts of fuel to break down raw materials,
such as limestone, in the process of making cement. While coal and
other fossil fuels have been the primary fuels burned in most cement
kilns, there has been a trend toward using other lower cost fuels,
such as hazardous waste. In February 1995, the Environmental
Protection Agency (EPA) determined that dust from cement kilns
burning hazardous waste as well as from those kilns that do not burn
hazardous waste warrants greater federal control to protect human
health and the environment. In making that determination, EPA noted
that as of 1990, cement kilns generated about 3.6 million metric tons
of dust that was placed in waste piles, quarries, or landfills, most
of which were unlined and uncovered. EPA also announced that it
would develop a tailored set of standards for cement kiln dust rather
than subject this dust to the entire set of regulations controlling
hazardous waste because of the severe negative economic impact these
regulations would have on the cement kiln industry. Establishing
different standards has stirred debate between the cement kiln
industry and the hazardous waste incinerator industry because cement
kilns burning hazardous waste may be required to comply with less
costly standards than those the hazardous waste incinerator industry
must comply with. Also, some environmental groups have stated that
cement kilns burning hazardous waste should be subject to all
hazardous waste regulations.
You expressed interest in our looking at EPA's decision-making
process with respect to regulating cement kiln dust. Therefore, we
are providing you with information on (1) what priorities EPA set for
making its determination about cement kiln dust; (2) whether EPA is
authorized to modify hazardous waste management requirements in
regulating cement kiln dust; (3) whether EPA believes that dust from
cement kilns burning hazardous waste should be regulated the same as
dust from those not burning hazardous waste; and (4) whether interim
actions can be taken to control cement kiln dust, in light of the
risks EPA believes that this dust poses.
RESULTS IN BRIEF
------------------------------------------------------------ Letter :1
According to EPA, making a determination on cement kiln dust was not
given as high a priority as developing standards for other wastes,
such as hazardous waste deposited in landfills, which were also under
statutory time frames but were considered to be a higher risk. By
statute, EPA has the authority to modify its hazardous waste
regulations to control cement kiln dust so long as those regulations
adequately protect human health and the environment. EPA believes
that cement kiln dust from both types of kilns, if improperly
managed, has the potential to adversely affect human health and the
environment. While EPA maintains that dust from kilns burning
hazardous waste as well as dust from kilns not burning this waste
should both be regulated, it has not yet determined whether it will
subject the dust generated by the two types of kilns to the same
regulations. Because it could take EPA several years to develop
regulations to control cement kiln dust, EPA and the states are
considering such actions as making greater use of existing regulatory
authority to enforce current controls over cement kiln dust as well
as entering into an agreement with the cement kiln industry that
could result in the industry's imposing additional controls over
cement kiln dust.
BACKGROUND
------------------------------------------------------------ Letter :2
The Resource Conservation and Recovery Act (RCRA) requires EPA to
identify which wastes should be regulated as hazardous waste under
subtitle C and establish regulations to manage them.\1 For example,
hazardous waste landfills, such as those used for disposing ash from
hazardous waste incinerators, generally must comply with certain
technological requirements. These requirements include having double
liners to prevent groundwater contamination as well as groundwater
monitoring and leachate collection systems.\2
In 1980 the Congress amended RCRA to, among other things, generally
exempt cement kiln dust from regulation under subtitle C, pending
EPA's completion of a report to the Congress and subsequent
determination on whether regulations under subtitle C were
warranted.\3 The Congress required that EPA's report on cement kiln
dust include an analysis of (1) the sources and the amounts of cement
kiln dust generated annually, (2) the present disposal practices, (3)
the potential danger the disposal of this dust poses to human health
and the environment, (4) the documented cases of damage caused by
this dust, (5) the alternatives to current disposal methods, (6) the
costs of alternative disposal methods, (7) the impact these
alternatives have on the use of natural resources, and (8) the
current and potential uses of cement kiln dust.
As of May 1994, there were about 115 cement kiln facilities operating
in 37 states and Puerto Rico.\4 Of these, 24 were authorized to burn
hazardous waste to supplement their normal fuel. Even with the 1980
exemption, certain aspects of cement kilns' operations must comply
with some environmental controls. Under the Clean Air Act, EPA
requires cement kiln facilities to comply with ambient air quality
standards for particulate matter. Under the Clean Water Act, EPA
regulates the discharge of wastewater and storm water runoff from
cement kiln facilities. Under the Comprehensive Environmental
Response, Compensation, and Liability Act (CERCLA or Superfund), EPA
can require cement kiln facilities to clean up contamination
resulting from cement kiln dust.
In August 1991, EPA's regulations for boilers and industrial furnaces
that burn hazardous waste took effect. While every cement kiln that
burns hazardous waste is subject to these regulations, its dust is
not classified as hazardous waste if at least 50 percent (by weight)
of the materials the kiln processes is normal cement-production raw
materials and the kiln's owner or operator demonstrates that burning
hazardous waste does not significantly affect the toxicity of the
dust. According to EPA Office of Solid Waste officials, of the 24
cement kilns authorized to burn hazardous waste, they are not aware
of any that are required to manage the dust as a hazardous waste.
Despite these existing controls, in making its regulatory
determination in February 1995, EPA stated that additional controls
over cement kiln dust are warranted under RCRA because of its
potential to harm human health and the environment. EPA also
determined that existing regulations, such as those under the Clean
Air Act, may also need to be improved because they are not tailored
to cement kiln dust or because their implementation is inconsistent
among the states. As partial justification, EPA cited 14 cases in
which cement kiln dust has damaged groundwater and/or surface water
and 36 cases in which cement kiln dust has damaged the air.\5 EPA
also cited the general lack of groundwater monitoring systems around
dust management units at cement kiln facilities and the current lack
of federal regulations to protect groundwater from the risks posed by
cement kiln dust. Furthermore, after collecting and analyzing
site-specific information, EPA concluded that potential risks did
exist at some facilities.
--------------------
\1 Nonhazardous solid wastes are covered under subtitle D of RCRA,
which is primarily implemented by state and local governments.
\2 Leachate, created by liquids percolating through layers of wastes
or soil in a landfill, can enter surrounding soils, underlying
groundwater, or nearby surface water.
\3 The Congress also directed EPA to study wastes from the
extraction, beneficiation, and processing of ores and minerals; the
exploration, development, and production of crude oil, natural gas,
and geothermal energy; and the combustion of coal and other fossil
fuels. These wastes, like cement kiln dust, were viewed as
high-volume, low-toxicity wastes and exempt from hazardous waste
regulations pending the results of EPA's reports and determinations.
\4 The data cited in this report are the latest available.
\5 EPA defined damage as contamination from metals that exceeds
federal or state standards for maximum concentrations in groundwater,
surface water, and/or air.
EPA DELAYED ITS DETERMINATION
BECAUSE OF HIGHER PRIORITIES
------------------------------------------------------------ Letter :3
Although in 1980 the Congress directed EPA to complete its report on
cement kiln dust by 1983 and to determine within 6 months thereafter
whether regulations were warranted, EPA did not do so. It completed
its report in December 1993\6
and issued its determination in February 1995.\7 EPA officials said
that the agency did not meet these statutory deadlines because, at
that time, EPA viewed completing its report on cement kiln dust as a
lower priority than other work.
According to EPA's Acting Chief of the Special Wastes Branch, the
agency ranked completing its report and determination on cement kiln
dust a low priority because cement facilities were considered to pose
minimal risk because of the very small proportion of them on EPA's
National Priorities List.\8 In addition, cement kiln dust exists in
smaller volumes in comparison to other high-volume wastes that EPA
was required to study, such as wastes from mining for ores and
minerals and exploring for oil and gas. EPA wanted to complete
studies of these high-volume, temporarily exempt wastes prior to
completing its study on cement kiln dust. For example, EPA estimated
that the mining industry generated 1.3 billion metric tons of waste
in 1982, and it completed its study on these wastes in 1985. EPA
officials said that they also needed to meet other statutory time
frames for completing standards for other wastes that the agency
placed a higher priority on, such as treatment standards for land
disposal of hazardous waste.
In settlement of a 1989 lawsuit filed against EPA because of its
failure to comply with the statutory time frames, EPA entered into a
consent decree to publish a report to the Congress on cement kiln
dust on or before December 31, 1993. This decree also called for EPA
to make a regulatory determination on cement kiln dust by January 31,
1995.
--------------------
\6 Report to Congress on Cement Kiln Dust (EPA530-R-94-001, Dec.
1993).
\7 Federal Register, Vol. 60, No. 25 (Feb. 7, 1995).
\8 The National Priorities List identifies the most serious
uncontrolled or abandoned hazardous waste sites for potential
long-term cleanup under Superfund.
EPA IS AUTHORIZED TO MODIFY
HAZARDOUS WASTE MANAGEMENT
REQUIREMENTS IN REGULATING
CEMENT KILN DUST
------------------------------------------------------------ Letter :4
RCRA specifically authorizes EPA to modify several requirements that
apply to hazardous waste in regulating cement kiln dust. EPA is
authorized to modify those requirements that would impose minimum
technological standards on new landfills or expansions of existing
landfills as well as those that impose corrective action to clean up
releases of wastes from units used to dispose of cement kiln dust.
EPA is authorized to modify these requirements to accommodate
practical difficulties associated with implementing them when
disposing of cement kiln dust as well as such site-specific
characteristics as the area's climate, geology, hydrology, and soil
chemistry. However, any modifications must ensure the protection of
human health and the environment.
Although RCRA allows EPA to modify several requirements and thus
propose different standards for cement kiln dust than those for
hazardous waste, EPA has not yet determined which standards might
differ and how they might differ. For example, according to Office
of Solid Waste officials, it is not clear whether EPA will include a
corrective action requirement to clean up releases from cement kiln
dust disposal units that is similar to its corrective action
requirement to clean up hazardous waste disposal units. These
officials said that EPA will likely focus its management standards on
dust generated in the future, as opposed to dust that already exists
at cement kiln facilities, because RCRA allows EPA to consider
several factors in developing standards for cement kiln dust
management, including the impact or cost any management standard may
have on the cement kiln industry. Furthermore, these officials said
that EPA has to be sensitive to the Congress's regulatory reform
efforts as well as the agency's goal of taking a more common sense
approach to regulating industry.
EPA HAS NOT DETERMINED IF DUST
FROM ALL TYPES OF KILNS SHOULD
BE REGULATED THE SAME
------------------------------------------------------------ Letter :5
Even though EPA has determined that additional controls are warranted
over dust from cement kilns burning hazardous waste as well as dust
from those kilns that do not, it has not determined if it will impose
the same standards or controls over dust from both types of kilns.
EPA's analysis found that concentrations of 12 metals in dust from
both types of cement kilns were at higher than normally occurring
levels. Dust from cement kilns burning hazardous waste had
concentrations of nine of these metals that were the same or lower
than dust from cement kilns that did not burn hazardous waste.
Conversely, EPA found that concentrations of three metals--cadmium,
chromium, and lead--were higher in dust from cement kilns that burn
hazardous waste. (See app. I.) Even though the concentrations of
these three metals were higher, EPA found that these increases did
not result in discernible differences in risk estimates between dust
generated by cement kilns that burn hazardous waste and those that do
not. EPA also analyzed the extent to which these metals leached, or
washed, out of the dust and found no significant difference between
cement kilns that burn hazardous waste and those that do not burn
this waste.
Although EPA has not yet determined what management standards it will
impose on cement kiln dust, Office of Solid Waste officials said that
the agency may regulate air emissions from cement kilns burning
hazardous waste differently from those that do not burn hazardous
waste. According to these officials, because dioxins and furans were
found in dust from cement kilns burning hazardous waste, EPA is
considering revising its regulations for boilers and industrial
furnaces to control their emissions. Even though the levels of these
hazardous wastes were generally low, EPA believes their presence
warrants concern.
INTERIM ACTIONS COULD BE TAKEN
TO MANAGE CEMENT KILN DUST
------------------------------------------------------------ Letter :6
Even though EPA did not conclude that cement kiln dust should be
classified as a hazardous waste, EPA did conclude that some
facilities (in addition to those where damage to surface and/or
groundwater and the air has been found) do have the potential to pose
a threat to human health and the environment. While EPA plans to
propose a program to control cement kiln dust within 2 years, if the
agency proceeds with developing federal regulations, it could be
several more years after that until cement kilns are required to
implement these controls. Interim and possible final actions to
reduce the current threat that cement kiln dust may pose at some
facilities include requiring the cement kiln industry to adopt dust
control standards without EPA's first having to proceed through a
lengthy regulatory development process and making greater use of
existing regulatory authority to control cement kiln dust.
One action EPA is considering to control this dust is the use of a
cement kiln industry proposal called an enforceable agreement. After
drafting the general terms of the agreement, the cement kiln industry
has been working with EPA and other interested parties to negotiate
what controls would be needed to protect human health and the
environment. Some possible industry controls are to require
landfills used to dispose of cement kiln dust to have such
site-specific features as hydrogeological assessments, groundwater
monitoring, surface water management, and measures to control
emissions of cement kiln dust. The agreement would also specify that
EPA would not impose subtitle C regulations on cement kiln dust. EPA
is currently analyzing the agreement's general terms to determine if
it is allowable under RCRA and whether it would sufficiently protect
human health and the environment.
EPA's consideration of this enforceable agreement to manage cement
kiln dust has triggered a negative response from environmental
groups. For example, the Environmental Defense Fund has questioned
EPA's authority to enter into these agreements and their
enforceability if EPA does not first develop regulations that contain
specific standards. In addition, the Fund questions whether these
agreements would provide the same level of protection as federal
regulations and whether they would allow for the public involvement
that occurs in developing regulations. The Fund also questions how
these agreements would affect the citizens' ability to sue and to
obtain information through the Freedom of Information Act and whether
these agreements would limit federal and state criminal and civil
enforcement authorities. Finally, the Fund questions whether these
agreements would limit the development of state programs to control
cement kiln dust. According to an Office of Solid Waste official,
EPA intends to decide by late September 1995 whether it will pursue
developing enforceable agreements to control cement kiln dust.
Should this approach be challenged in the courts, however, controls
over cement kiln dust could be further delayed.
A second action under consideration is for EPA and the states to make
greater use of existing regulatory authority to control cement kiln
dust. Although EPA has determined that current regulations need to
be improved for the proper management of cement kiln dust, in the
past EPA regional offices and the states have used existing
authorities at some facilities to control surface water runoff,
emissions from dust piles, and groundwater contamination (i.e., the
damage cases mentioned earlier). For example, according to an
environmental inspector in Ohio, the state used an enforcement
authority under its Remedial Response Act to better control runoff
from waste piles that was contaminating a nearby stream. According
to a waste management official in Michigan, the state used
enforcement authority under its Air Pollution Control Act to better
control emissions from dust piles. EPA has also used the Superfund
program to clean up groundwater contamination at two facilities.
In the course of completing its regulatory determination, EPA's
Office of Solid Waste collected information on 83 cement kiln
facilities and conducted a series of studies on risk-screening and
site-specific risk-modeling that could be used to determine whether
existing regulatory authority should be used to control cement kiln
dust at particular cement kilns. On the basis of the information
collected and analyzed, EPA projected that several cement kiln
facilities may be posing a high risk because of such factors as the
amount of metals that may exist in dust disposed at those facilities,
the lack of dust management controls at those facilities, and other
facility-specific factors, such as proximity to agricultural lands.
However, EPA's Office of Solid Waste has not provided the results of
its risk-screening and risk-modeling studies to other EPA offices or
the states that are responsible for investigating facilities and
taking necessary enforcement actions. (See app. II for additional
information on the results of these studies.) According to Office of
Solid Waste officials, much of this information is available in the
public docket and EPA's contractor has the computer tapes that were
used to develop the risk estimates. However, because they did not
believe that most facilities posed the degree of risk that warranted
emergency action, they did not provide this information directly to
EPA's Office of Enforcement and Compliance Assurance, its regional
officials, or state enforcement officials.
EPA's RCRA officials in four regions with cement kilns whose dust
potentially poses a risk to groundwater said they would be interested
in having the facility-specific information EPA's Office of Solid
Waste developed to prepare its report and determination. They said
that they could provide the information to state environmental
officials for the states' use or could take enforcement action
themselves if the regions believed the situation warranted it. In
those instances in which EPA or the states lack clear enforcement
authority, other actions, such as assessing facilities to better
understand the risks and working cooperatively with cement kiln
owners/operators to reduce these risks, could be taken. Similarly,
EPA air and water officials said they would be interested in having
facility-specific information for these purposes.
CONCLUSIONS
------------------------------------------------------------ Letter :7
It may be several years before EPA completes its management control
program for cement kiln dust regardless of whether it decides to
issue new regulations or adopt the use of an enforceable agreement to
control this dust. EPA obtained information on 83 cement kiln
facilities that it used to conduct a series of risk-screening and
site-specific risk- modeling studies. While this information is
readily available and much of it is in the public docket, EPA has not
distributed it to EPA's regional or state enforcement officials
because the agency did not believe that the estimated risks warranted
emergency action. Even so, EPA believes that some facilities,
because of the manner in which their cement kiln dust is managed,
could pose a risk. EPA regional and state enforcement officials
believe that this information could assist them in determining if
action should be taken at some facilities prior to EPA's finalizing
its management program to control cement kiln dust.
RECOMMENDATION
------------------------------------------------------------ Letter :8
We recommend that the Administrator, EPA, provide to EPA's regional
officials and state enforcement officials the risk-screening and
site-specific risk-modeling information developed during its study of
cement kiln dust so they can use this information to determine
whether interim actions are needed to protect human health and the
environment.
AGENCY COMMENTS
------------------------------------------------------------ Letter :9
We provided a draft of this report to EPA for its comments. We met
with EPA officials, including the Acting Director, Waste Management
Division, Office of Solid Waste, who generally concurred with the
information presented in this report. They agreed that it would be
appropriate for them to provide EPA's regional officials and state
enforcement officials information that may be useful to determine
whether action should be taken to reduce the risks posed at cement
kiln facilities prior to the agency's finalizing its management
program to control dust from cement kilns. Office of Solid Waste
officials also suggested we clarify certain technical points. We
have revised the report accordingly.
SCOPE AND METHODOLOGY
----------------------------------------------------------- Letter :10
To determine what priorities EPA set for making its regulatory
determination on cement kiln dust, we interviewed officials from
EPA's Special Wastes Branch in its Waste Management Division, Office
of Solid Waste. To determine if EPA is authorized to modify
hazardous waste management requirements in regulating cement kiln
dust, we reviewed RCRA and EPA's regulatory determination on cement
kiln dust. To determine whether EPA believes that dust from cement
kilns that burn hazardous waste should be regulated the same as dust
from those not burning such waste, we reviewed EPA's Report to
Congress on Cement Kiln Dust, its regulatory determination, and
public comments received on that report as well as on other
documents. We also discussed the basis for EPA's determination with
its Special Wastes Branch officials as well as officials representing
the hazardous waste industry, the cement kiln industry, and
environmental groups. To determine whether interim actions could be
taken to control cement kiln dust while EPA is developing its
management control program, we reviewed EPA's legal authority for
taking action at facilities that may pose a threat to human health
and the environment, reviewed cases in which EPA or the states have
used this authority in the past, and discussed EPA's risk-screening
and risk-modeling results with Office of Solid Waste officials. We
also discussed options EPA and the states have with Special Wastes
Branch officials in the Office of Solid Waste, Office of Enforcement
and Compliance Assurance officials, EPA attorneys, and EPA and state
environmental enforcement officials. We conducted our review between
March and June 1995 in accordance with generally accepted government
auditing standards.
As discussed with your office, this report does not address new
information that you provided us recently relating to metals in
cement kiln dust. We agreed that we will address that information
separately.
--------------------------------------------------------- Letter :10.1
As arranged with your office, unless you publicly announce this
report's contents earlier, we plan no further distribution until 30
days after its publication. At that time, we will send copies of
this report to the Administrator of EPA and make copies available to
others upon request.
Please contact me at (202) 512-6112 if you or your staff have any
questions. Major contributors to this report are listed in appendix
III.
Sincerely yours,
Peter F. Guerrero
Director, Environmental
Protection Issues
METALS FOUND IN CEMENT KILN DUST
AT BOTH FACILITIES BURNING
HAZARDOUS WASTE AND FACILITIES NOT
BURNING HAZARDOUS WASTE
=========================================================== Appendix I
Comparison of the amounts of
metals found in dust from
kilns burning hazardous waste
to the amounts found at kilns
Metal not burning hazardous waste
----------------------------- -----------------------------
Antimony Same or lower
Arsenic Same
Barium Lower
Beryllium Same or lower
Cadmium Higher
Chromium Higher
Lead Higher
Mercury Same or lower
Nickel Same
Selenium Same
Silver Lower
Thallium Lower
------------------------------------------------------------
Source: EPA's Office of Solid Waste.
RESULTS OF EPA'S STUDIES ON
RISK-SCREENING AND SITE-SPECIFIC
RISK-MODELING FOR 83 CEMENT KILN
FACILITIES
========================================================== Appendix II
EPA used a model to analyze the effect cement kiln dust could have at
52 facilities if they did not have adequate dust suppression controls
for their waste piles. EPA's model projected that over half of these
facilities would exceed EPA's health standards for fine particulate
matter at plant boundaries and, potentially, at nearby residences.
Although almost all of these facilities have some controls to
suppress cement kiln dust, EPA does not have information on the
adequacy of these controls and EPA officials also noted that they saw
cement kiln dust blowing during some visits to 20 facilities.
EPA used the same model to analyze the effects of water running off
of dust piles at 83 of the facilities. The model projected that 25
facilities could pose higher than acceptable cancer risks or
noncancer threats to subsistence farmers and fishermen. Seven of
these facilities did not have runoff controls. EPA also estimated
that 19 facilities could pose a risk because of dioxins and furans.
EPA cautioned, however, that these risk results were based on very
limited sampling and modeled worst-case scenarios of unusually high
dioxin and furan levels. EPA further cautioned that all of the
results from its analyses of indirect exposure risks should be
carefully interpreted because its model was still under peer review.
Even so, Office of Solid Waste officials said that the results of all
of EPA's analyses were cause for concern.
EPA's analysis of the effects of cement kiln dust on groundwater
found that about half of the cement kiln facilities were built on
bedrock having characteristics that allow for the direct transport of
groundwater offsite. In its analysis of 31 of these facilities, EPA
found that dust from 13 of them could contaminate groundwater at
levels that could exceed health standards. None of these 13
facilities had installed man-made liners under their dust piles and
11 lacked leachate collection systems. EPA also found that
groundwater at three of these facilities was within 10 feet of the
bottom of their dust piles; EPA did not have information on the depth
to groundwater at the remaining 10 facilities. In addition, some
facilities managed cement kiln dust in quarries that could
subsequently fill with water; if this occurs, leachate could more
readily contaminate groundwater.
In addition to the potential risks from the disposal of cement kiln
dust, EPA is concerned over the use of this dust as a substitute for
lime to fertilize agricultural fields. According to EPA, this use of
cement kiln dust could pose cancer risks and noncancer threats for
subsistence farmers if that dust contains relatively high levels of
metals and dioxins.
MAJOR CONTRIBUTORS TO THIS REPORT
========================================================= Appendix III
ENVIRONMENTAL PROTECTION ISSUES
AREA
------------------------------------------------------- Appendix III:1
Richard P. Johnson, Attorney
Gerald E. Killian, Assistant Director
Marcia B. McWreath, Evaluator-in-Charge
Rita F. Oliver, Senior Evaluator
Mary D. Pniewski, Senior Evaluator