Comment on Thoroughbred's Request for Special Waste Designation

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Comment on Thoroughbred's Request for Special Waste Designation  Posted: August 5, 2002


Kentucky Resources Council, Inc.

Post Office Box 1070

Frankfort, Kentucky 40602

(502) 875-2428 phone (502) 875-2845 fax



August 5, 2002


LeMoyne Pilcher

Division of Waste Management

14 Reilly Road

Frankfort, Kentucky 40601


Re: Public Notice: Thoroughbred Special Waste Petition


To Whom It May Concern:


These comments are filed by the Kentucky Resources Council, Inc. in response to the public notice inviting comment on the request by Thoroughbred Generating Company, LLC for designation of coal combustion wastes from its coal-fired electric generating station as "special wastes" pursuant to KRS 224.50-760 and 401 KAR 45:210. According to the application, Thoroughbred Generating Company LLC intends to construct and operate a coal-fired electric generating station in Muhlenberg County, generating three separate waste streams for which it seeks "special waste" designation: fly ash, bottom ash, and flue gas desulfurization (FGD) sludge.


The Kentucky Resources Council, Inc. (KRC) is a non-profit environmental advocacy organization organized under the laws of the Commonwealth of Kentucky and dedicated to prudent use and conservation of the natural resources of the Commonwealth. After review of the request for designation, including the May 15, 2002 Application for Special Waste Designation and the May 29, 2002 letter from Fuller, Mossbarger, Scott, and May Engineers, KRC offers these comments:


1. KRS 224.50-760 Requires That The Wastes Be Classified As Industrial Solid Wastes Rather Than "Special" Wastes


KRS 224.50-760(1)(a) defines "special wastes" to include "those wastes of high volume and low hazard which include but are not limited to "utility wastes (fly ash, bottom ash, scrubber sludge)[.]" That statutory provision confers discretionary authority to the cabinet to designate "other wastes" as special wastes. KRS 224.01-010(31) defines wastes resulting from industrial activities as "solid waste" and provides certain enumerated exceptions, including one applicable to "special wastes as designated by KRS 224.50-760[.] (Emphasis added).


KRS Chapter 224 does not define the term "utility," but the General Assembly has defined that term at KRS 278.010. Broadly stated, the term includes those facilities generating electricity for distribution to retail customers at rates and within service areas regulated by the Public Service Commission. Absent specific designation of the particular waste stream by the Natural Resources and Environmental Protection Cabinet, in a manner consistent with KRS 224.50-760, the three identified waste streams are not "special wastes" since the Thoroughbred Generating plant is proposed as a "merchant" plant whose rates and service are not regulated by the PSC.


The applicants' position from the supporting documentation is that it believes itself to be a utility despite not being regulated by the PSC entitling its' wastes to "special waste" status. The application is submitted to "confirm classification" of the wastes as special wastes, "[a]lthough Thoroughbred does not believe the statue (sic) would ultimately be interpreted to create a disparity between similarly situated power plants[.]"


The Cabinet is correct in interpreting KRS 224.50-760 as excluding non-utility coal combustion wastes generated by merchant power plants from the categorical definition, and in so doing recognizes an intentional differentiation by the General Assembly of those electric generating facilities that are public utilities and those "merchant" facilities generating wholesale power for sale at market prices.


Through the enactment of Senate Bill 257, the legislature reaffirmed the long-standing distinction between facilities whose rates and service area are subject to rigorous scrutiny through issuance of a certificate of public convenience and necessity, and those facilities that are not. Preferential statutory treatment is accorded to these regulated utilities because they serve a public need for reliable power at regulated rates. Thus, for example, KRS 100.347 provides an exemption for utility facilities from planning and zoning, defining "utilities" in a manner consistent with KRS Chapter 278. Senate Bill 257 contains such a differentiation, recognizing that while both new merchant power plant units and new regulated "utility" units should undergo a siting assessment and receive a certificate of site compatibility, that the ability to require a relocation of the facility would not be available to the commission in reviewing a utility's siting; whereas the siting board created under Senate Bill 257 could require relocation of the site of a merchant plant.


The distinction is a legitimate one, since merchant plants such as the Thoroughbred Generating facility are not needed to meet Kentucky's native load needs, nor is it intended for such purpose. While communities are required to tolerate a certain degree of the environmental burden of hosting utility plants, the legislature has recognized that merchant plants are not entitled to similar preferential treatment and are not exempt from planning and zoning under KRS 100.347. So too, in the management of industrial wastes, when the legislature identifies "utility" wastes as a category of special wastes in KRS 224.50-760, rather than using a broader phrase such as "all wastes from coal combustion", it must be presumed that the legislature knew the scope of the term "utility". That distinction must be respected by the agency.


2. Assuming That These Three Waste Streams Are Eligible For Designation As Special Wastes, A Designation Is Premature Absent Specific And Adequate Data Concerning The Particular Wastes And The Combustion Conditions and Equipment, and On The Hydrogeology Of The Proposed Disposal Site


Assuming for the sake of argument that the three waste streams are eligible for a petitioned designation as special wastes,1 the designation decision should be deferred pending submittal of actual and sufficient data on the chemical composition and leaching characteristics of the wastes based on combustion of comparable fuels under a range of fuel mix and combustion conditions using either the Thoroughbred generating unit or another unit of like combustion and pollution control configuration. For while it is asserted that the chemical and physical profile of the wastes will be "identical" to those of "similar coal-fired plants using Western Kentucky coal," in truth there is likely to be a degree of variability in the chemical profile of the wastes based on the fuel composition and blend, combustion conditions and management of the wastes. Fernandez-Turiel, Mobility of heavy metals from coal fly ash, Environmental Geology (1994) 23:264-270.


Additionally, if the facility utilizes waste coals (off-specification; higher sulfur or ash) and coal wastes as part of the fuel mix, and if the coal is not washed in order to remove additional impurities, there is a possibility of higher levels of certain contaminants in these wastes than might otherwise be present.


Concerning the leaching characteristics of the wastes, the data submitted by the applicant concerning representative profiles of indicates that for many of the waste constituents, the mean leachate concentrations of metals of concern exceed drinking water maximum contaminant levels (themselves not health-based standards).


The applicant suggests that in order to assess the potential for impact on private water wells and groundwater, that a dilution and attenuation factor of 100 should be applied. KRC believes that application of any attenuation factor is inappropriate unless it is based on site-specific geologic data and appropriate characterization of the hydrogeologic regime for the intended disposal site(s).


The use of the 100 DAF for TCLP analysis of metals assumes that unless a constituent leaches one of the metals or other constituents (such as benzene) in excess of 100-times the drinking water standard, the waste is "non-hazardous" and can be managed as a solid waste.


It is not appropriate to assume, for purposes of determining fate and transport of the metals in the environment, that 100 times dilution and attenuation will occur prior to detection at the point of compliance. The first reason for rejecting the application of any DAF is that in the absence of site-specific data, little or no attenuation can be credited if the values are to be sufficiently conservative. The EPA discussion of the application of the DAF in the development of the TCLP test appears to have been grounded in several assumptions that are unlikely to occur in the geologic context of the western Kentucky coalfields. The assumption of attenuation of contaminants through groundwater flow assumes primary permeability through pore spaces as the flow mechanism; an assumption inappropriate for much of the coalfields of western Kentucky, where secondary "fracture-dominated" permeability in which the water travels through fractures and bedding planes rather than through interstices in the rock itself, is more typical. Additionally, the severely-disturbed nature of the geologic strata from past mining and blasting practices can accentuate fracturing and accelerate travel time. These two factors dictate that the assumptions concerning the fate and transport must assume rapid travel time with little attenuation under secondary flow conditions, absent site-specific data demonstrating the absence of fracturing and the presence of competent tightly-pored strata to attenuate pollutant concentrations.


Absent appropriate characterization of the hydrogeology of the proposed disposal site, and assessment of the nature and occurrence of groundwater in the area including the physical and chemical composition, thickness, and competence of the underlying strata and the recharge, flow and discharge characteristics of the aquifer(s), application of any DAF (and particularly application of a DAF of 100) is inappropriate.


Regarding the potential for adverse impacts on groundwater from disposal of coal combustion wastes, KRC disagrees that the wastes are, by composition or by leaching potential, "low hazard." The 1988 U.S. Environmental Protection Agency report to Congress concerning coal combustion wastes (including fly ash, bottom ash, boiler slag and flue gas emission control wastes) acknowledged the range of toxicity and potential for causing groundwater contamination among and within the categories of coal combustion waste. According to the EPA Report Wastes from the Combustion of Coal by Electric Utility Power Plants, EPA/530-SW-88-002:


The primary concern regarding the disposal of wastes from

coal-fired power plants is the potential for waste leachate to cause ground-water contamination. Although most of the materials found in these wastes do not cause much concern (for example, over 95 percent of ash is composed of oxides of silicon, aluminum, iron and calcium), small quantities of other constituents that could potentially damage human health and the environment may also be present. These constituents include arsenic, barium, cadmium, chromium, lead, mercury and selenium. At certain concentrations these elements have toxic effects. Id., at ES-4.


While the findings of the EPA Report and review of industry-generated studies indicated generally that metals did not leach out of coal combustion waste (CCW) at hazardous (100 x drinking water standards) levels, hazardous levels of cadmium and arsenic were found in ash and sludge samples, and boiler cleaning wastes sometimes contained hazardous levels of chromium and lead. Id.


While acknowledging that coal combustion wastes (fly ash and scrubber sludge) do not usually exhibit sufficiently high toxic properties to be classified as hazardous based on TCLP toxicity, a recent study of CCW in Indiana indicated that CCW does contain high enough concentrations of leachable toxic elements to create significant environmental concern. Boulding, J. Russell, Disposal of Coal Combustion Waste in Indiana: An Analysis of Technical and Regulatory Issues (1991).


Among the significant findings of this report, which was based on extensive literature review and analysis of coals burned in Indiana utilities (including Kentucky coals), and which militate against a finding of "low hazard" based on the ability of coal combustion wastes to leach metals of concern into the environment, were:


l. Neither EP nor TCLP tests provide a good indication of leachability of CCW in natural disposal settings. Long-term leaching tests conducted until equilibrium has been achieved for each element of concern, using a leaching solution that approximated percolating groundwater, would give a more accurate depiction of ground-water contamination potential at a disposal site.


2. l7 potentially toxic elements are commonly present in CCW: aluminum, antimony, arsenic, barium, beryllium, boron, cadmium, chromium, copper, lead, manganese, mercury, molybdenum, nickel, selenium, vanadium, and zinc.


3. Fluidized bed combustion (FBC) wastes retain volatile and semi-volatile elements in the bottom ash to a greater extent than conventional pulverized coal combustion, thus enhancing the leachability of FBC waste elements.


4. Leachates from coal power plant ash and flue gas desulfurization wastes typically exceed drinking water standards, but by a factor less than hazardous levels (i.e. 100 x DWS). The major leaching studies on CCW indicate that drinking water standards are typically exceeded by CCW ash leachate at a factor of 1.1 to 10, and often by a factor greater than 10 for one or more elements.


5. Disposal of CCW in or near mine workings may be of particular concern, due to the increase in surface area available for leaching of elements resulting from fracturing of overburden and confining layers; and due also to the higher total dissolved solids levels in mine spoils that compete for sorption sites on solids with toxic elements released from the buried ash.


The EPA Report and Boulding study suggest that the management of special wastes at the proposed site must be attuned to the variability of the concentrations of potentially toxic elements in the waste, and to the unique problems presented by the previously-mined nature of the site, and should consider whether the type of waste is from a fluidized bed combustor.


The 1988 EPA Report concluded preliminarily that CCW need not be regulated under RCRA Subpart C as hazardous, but rather that the wastes should continue to be regulated under Subpart D as solid wastes. This conclusion was recently reaffirmed by the agency on an interim basis. In so recommending, EPA determined that while field observations detected off-site migration of potentially hazardous constituents from utility waste disposal sites, reflecting a potentially larger problem than laboratory analyses would suggest, the use of mitigative measures under Subpart D such as installation of liners, leachate collection systems, and ground-water monitoring systems and corrective action to clean up ground-water contamination, would be adequate for protecting public health and the environment. The EPA recommendation was predicated on the application of such measures to the management of CCW. Id. at ES 4-5.



Consistent with the evidence of problems posed by this type of waste stream and disposal site identified by the literature,2 and consistent with EPA?s recommendations, the regulatory determination should reject the special waste status in favor of more rigorous controls on placement of the waste, strict limits on concentrations of contaminants in discharge water, and liners in all disposal cells and leachate storage, management ponds or lagoons. In making a determination on whether these three waste streams are entitled to special waste status and on whether the disposal might result in environmental contamination, the agency should:


a. require evaluation of actual ash and FGD waste samples of the fuel under comparable combustion conditions in order to assure that the ash samples adequately reflect the composition and leaching characteristics of the waste streams proposed for disposal;


b. determine whether the TCLP testing is sufficient to characterize the leachability of the ash under disposal conditions. Since the ash will tend to be alkaline if co-disposed with FBC sludges, other tests, such as a neutral water 14-day or other types of test might be needed to more fully reflect the release of dissolved metals under long-term conditions.


c. assess the potential for presence and environmental fate of unburned or partially burned organics. For example, FBC wastes, because the units burn cooler, more organics are uncombusted and remain in the ash. The applicant's data should adequately replicate actual operating temperature ranges and account for all organics.


d. determine the fate and transport characteristics of the intended disposal site(s).


Absent adequate specific information concerning the chemical composition and leaching characteristics of the specific proposed waste streams and the disposal sites, a blanket designation of these three waste streams as "special" would be inappropriate. KRC requests that pending submittal of this information, the request for special waste designation for the fly, bottom and fluidized bed combustion wastes from the proposed Thoroughbred Generating Company Muhlenberg County facility be denied.


KRC incorporates herein by reference, as if set out below, the Cabinet's December 2001 Cumulative Environmental Assessment of the Environmental Impacts Caused By Kentucky Electric Generating Units, and the Boulding study, and in addition, a document entitled Documented Cases of Ground-Water Contamination From Disposal of Coal Combustion Waste (1985). A copy of the Boulding study, which was previously submitted by KRC in conjunction with the Kentucky Mountain Power landfill comments submitted by the Council, is being sent under separate cover.






Tom FitzGerald




1 As a matter of statutory interpretation, one might view extension of the special waste classification on a case-by-case basis to the wastes of a non-utility power generating sources as inconsistent with the intent of the legislature to restrict the availability of the classification to "utility" wastes.

2 The Cabinet's "Cumulative Environmental Assessment of the Environmental Impacts Caused By Kentucky Electric Generating Units," December 2001, documents in Appendices D and E the potential for leaching and ecological consequences of leaching of constituents from coal combustion wastes. In particular, the conclusions of the study with respect to concentrations of arsenic and barium, and the leaching of arsenic above the new MCL from the Mill Creek Station despite the mixing of the ash with scrubber sludge and the "stabilization" as Poz-o-tec, suggest that the suggestion for application of any DAF and the assumption of low hazard are misplaced.



By Kentucky Resources Council on 08/05/2002 5:32 PM
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