KRC Comments In Opposition To LGE Coal Combustion Waste Landfill

« Latest News
These preliminary comments are submitted on behalf of the membership of the Kentucky Resources Council, Inc., a nonprofit environmental advocacy organization incorporated under the laws of the Commonwealth of Kentucky and dedicated to prudent use and conservation of the natural resources of the Commonwealth. KRC members include individuals with property and other interests that will be adversely affected within the meaning of relevant statutes if the draft special waste landfill permit is issued as proposed.

The proposed landfill would cover an area of 189 acres, and would create 33,400,000 cubic yards of airspace for disposal of coal combustion wastes, including bottom ash, fly ash, flue gas desulfurization (FGD) wastes, and mill rejects. According to the Fact Sheet, the applicant has proposed a liner system consisting of 6 inches of prepared subgrade, overlain by 24 inches of compacted soil, a 60-mil low-density geomembrane, cushion geotextile or a drainage net, a 12-inch leachate collection system, and 24 inches of protective soil cover. The cap system consists only of 12 inches of recompacted soil covered by a 12-inch vegetative soil layer, all but assuring that over time, rainfall will infiltrate into the waste after closure due to the lack of a compacted clay cap and drainage layer to divert infiltration, and a low-density FML to minimize root penetration into the final cap.

KRC has reviewed the permitting file and draft permit, and has these preliminary concerns. Additional comments will be submitted prior to the close of the comment period.


The permit application has not accurately or adequately characterized the Laurel Dolomite aquifer system. The Cabinet proposes a permit condition requiring a groundwater monitoring plan to accurately characterize groundwater flow and flow systems in the Laurel Dolomite, which is the uppermost bedrock aquifer on the site, and for monitoring of the groundwater in the Laurel Dolomite for releases of contamination.

Yet despite acknowledging that the Laurel Dolomite aquifer system has not been sufficiently characterized, the application proposes, by letter dated July l22, 2016, and the Cabinet proposes to approve a permit allowing blasting, significant excavation, diversion of surface flow, and grading above the base of the Laurel Dolomite formation in order to facilitate the establishment of a prepared subgrade and to minimize surface run-on.

Each of the proposed activities has the potential to change the hydrology of the Laurel Dolomite formation, and respectfully, no permit should be issued, and no activity should be authorized for the site, either above or below the Laurel Dolomite, until the formation is properly characterized, both individually and in relation to the remainder of the hydrogeologic regime at the site.

401 KAR 45:110 mandates that the engineering design of the special waste landfill shall demonstrate compliance with the environmental performance standards of 401 KAR 30:031 and the siting standards of 401 KAR 45:130, considering, among other things, the physical and chemical characteristics of the waste, including compatibility with the liner, cover, and water that may come in contact with the waste, and considering the ?hydrogeologic characteristics of the site including quality, quantity, current use, and direction of groundwater flow[.]”

Absent a complete characterization of recharge and discharge, flow characteristics and chemistry of the Laurel Dolomite formation, which is acknowledged to be the uppermost aquifer, the applicant cannot demonstrate compliance with the design requirements of 401 KAR 45:110 Section 1.

Nor, in the absence of such characterization, can the applicant demonstrate nor can the Cabinet find, that the uppermost aquifer is capable of being monitored in a manner that detects the presence of any constituent listed in 401 KAR 45:160 and that corrective action can be performed if there is any migration of leachate from the site.

Finally, absent complete characterization of the groundwater regime above the Laurel Dolomite, the applicant has not provided adequate baseline groundwater quality characterization as required by 401 KAR 45:160 Section 7(2).

The allowance of commencement of excavation and blasting anywhere on the property has significant potential to alter the groundwater flow characteristics in the uppermost aquifer prior to proper characterization in a manner that is inconsistent with the regulations. The presence of springs in the Laurel Dolomite suggests, as noted in correspondence between Todd Hendricks and LGE on March 10, 2015, is indicative of an aquifer that is karstic in nature, with features particularly vulnerable to collapse, plugging, or contamination from blasting, compaction and excavation to prepare a subgrade. It is not only the waste placement, but the site preparation itself, including diversion of surface flow, that can cause damage to the uppermost aquifer, and no such activity can lawfully occur prior to adequate site characterization and design in accordance with site constraints.

For these reasons, the draft permit should be withdrawn pending a demonstration that the quality, recharge, discharge, and flow characteristics of the Laurel Dolomite, and the hydrogeologic connection of the karstic features of that formation with the hydrogeology of the remainder of the site, have been demonstrated.


The presence of karst features, including sinkholes, within the footprint of the proposed landfill, has been documented, yet the Cabinet is proposing to authorize placement of special waste in a landfill above such features. 401 KAR 45:130 establishes the siting requirements for special waste landfills, and prohibits placement of waste within 250 feet of a sinkhole, or other karst feature suggesting the rapid transmission of water to the water table.

The Cabinet is without regulatory authority to grant a variance or waiver from the buffer zone requirements of 401 KAR 45:130 Section 1. “Shall” is the language of command, and grants no discretion to the agency to waive buffer zones such as those contained in 401 KAR 45:130 Section 1(3). The agency is as bound to comply with its lawfully-promulgated regulations as is a regulated entity seeking a permit to engage in landfilling of coal combustion wastes.

The draft permit should be withdrawn in order to allow redesign that avoids waste placement anywhere within 250 feet of a sinkhole, and pending thorough characterization (including dye tracing) of the complex hydrogeologic regime on the property in order to determine the flow characteristics so as to assure compliance with 401 KAR 45:130 Section 1(3).


Among the technical and operating requirements for special waste landfills is the requirement that the applicant demonstrate that the engineering design will comply with the environmental performance standards of 401 KAR 30:031 and the siting requirements of 401 KAR 45:130, considering, among other factors, the “physical and chemical characteristics of the waste, including compatibility of the waste” with the liner, the cap, and water that may come into contact with the waste. 401 KAR 45:110 Section 1(1). A key attribute of the special waste rules is that the design of the landfill is tailored to the waste characteristics so as to prevent violation of the 30:031 performance standards.

The use of TCLP or SPLP tests to characterize the chemical characteristics of the coal combustion wastes is grossly inadequate to fully characterize the waste chemistry and the interaction of the wastes with liner, cap and infiltrating precipitation and surface flow. A more robust array of long-term and serial batch leaching tests, such as the LEAF protocol, is needed in order to allow characterization of the chemical characteristics of leachate over time and to assure that the design is both compatible with the landfill design and with environmental performance standards over time.

Coal combustion waste contain a number of constituents of potential environmental and public health concern. As noted by EPA in the 1988 publication 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."

The National Academies of Science acknowledged the threat posed by disposal of coal ash in mines, landfills and surface impoundments. Both the NAS and EPA have documented extensively the contamination of groundwater and surface water by leached constituents from coal ash.

As improvements continue to be achieved in both pre- and post-combustion scrubbing and capture of particulates and metals, the composition and potential toxicity of the wastes and leachate will change. Mercury removal from coal combustion emissions alone may increase the concentration in fly ash by 184 times, according to one report.

Additionally, the composition of FGD wastes is of concern due to leaching potential. The 2009 EPA Report, Steam Electric Power Operations Point Source Category Final Detailed Study Report, 821-R-09-008, concluded that:

"FGD wastewaters contain significant levels of metals including bioaccumulative pollutants such as arsenic, mercury, and selenium, and that FGD and ash transport wastewaters can impact the environmental by surface discharges, leaching, and by attracting wildlife who are then exposed."

Unfortunately, the testing that appears to have been used by LGE to characterize the waste was based on short-term single batch TCLP and SPLP testing. Such testing is inadequate to form a basis for determining the interactions of the waste chemistry with liner, cap, and water infiltrating into the waste. The use of TCLP or SPLP testing is not appropriate as a test to characterize the long-term leaching potential of wastes and will not enable prediction of the hydrologic consequences of introduction of such wastes into the environment by land disposal so as to allow any reasoned determination that the cap and liner design will prevent contamination of surface or groundwaters in communication with the landfilled waste.

TCLP and SPLP tests measure the quantity of inorganic constituents that readily leach out of a coal ash sample under controlled laboratory conditions for short periods, and are not designed to simulate actual conditions in the landfill where the CCW is proposed to be placed. The actual conditions are more geochemically complex, involving placement of large volumes of coal ash in much more concentrated environments for leaching, a variety of overburden materials, and changing chemistries of rainwater and leachate moving through the coal ash. Missing from the SPLP is the ability to predict coal ash leaching behavior over time. Coal ash placement will produce leachate over decades, not hours. Different constituents in CCW and the surrounding overburden will become more or less soluble as these factors change. Not surprisingly, researchers at US EPA, US DOE, and at numerous universities have found standard leaching tests, such as the SPLP, to be unreliable, routinely failing to predict the leaching behavior of numerous contaminants in coal ash at CCW disposal sites. As a result, concentrations of metals and other constituents in groundwater affected by CCW are often markedly different from concentrations generated in tests such as the SPLP. Analysis of total metals does not provide any indication of the leaching potential or leaching characteristics of coal combustion wastes, and the U.S. EPA has recommended that management decisions not be based on total content of constituents in coal combustion residues since total content does not consistently relate to quantity released.

The TCLP (Toxicity Characteristic Leaching Procedure) is the EPA test method used to evaluate the leachability of metals, organic compounds and pesticides from wastes into groundwater under one set of disposal conditions – co-disposal of CCW in a municipal solid waste landfill. In principle, the TCLP simulates the leaching of constituents from the waste into groundwater under conditions found in a municipal solid waste landfill. However, the TCLP has been applied to wastes in disposal and management settings other than municipal waste co-disposal.

The EPA’s Science Advisory Board has criticized the TCLP protocol on the basis of several technical considerations, including the test’s consideration of leaching kinetics, liquid-to-solid ratio, pH, potential for colloid formation, particle size reduction, aging, volatile losses, and co-mingling of the tested material with other wastes (i.e., co-disposal).

Specific limitations of the TCLP include these:

• TCLP underestimates leachate from some high alkaline wastes or environments.
• TCLP does not account for the conditions of waste disposed of in a monofill.
• TCLP may underestimate the chelation-facilitated mobility of some waste constituents.
• TCLP does not account for oxidation/reduction reactions occurring in landfills.
• TCLP may not predict the long-term mobility of organic constituents in some treated wastes.
• TCLP does not predict releases to non-groundwater pathways.

The use of short-term single batch leaching tests, such as TCLP, EP-Toxicity, SPLP, and ASTM-D2987 (Shake Extraction) are not reflective of field conditions and long-term leaching potential. According to Ann Kim of the National Energy Technology Laboratory:

"[t]he utilization of coal combustion by-products (CCB) as bulk fill and mine backfill has raised questions about the potential contamination of surface and groundwater. . . . Leaching is related to the solubility of a specific compound and can be influenced by pH, temperature, complexation, and oxidation/reduction potential. . . . Regulatory tests and standard methods are not necessarily appropriate for leaching tests intended to stimulate natural processes."

Kim, CCB Leaching Summary: Survey of Methods and Results.

As Gregory Helms with the EPA Office of Solid Waste explained, the EPA Science Advisory Board commented on the TCLP test method in 1991 and again in 1999, expressing concern “about overbroad use of the TCLP test.” Id. The SAB found that TCLP is a screening test that evaluates leaching potential under a single set of environmental conditions. The SAB has expressed concern over the use of the TCLP when it has been applied to determine the leaching potential of wastes in disposal settings other than municipal waste co-disposal has been criticized.

The U.S. EPA utilized a new multi-tiered testing framework in a research program designed to evaluate the potential for mercury release from various types of coal combustion wastes. The alternative framework evaluates the potential leaching of waste constituents over a range of values for parameters that affect the leaching potential. In explaining the EPA decision to utilize a leach testing approach developed by Kosson et al. at Vanderbilt in evaluating leaching from coal combustion residues resulting from mercury emissions controls, Helms explained that TCLP wasn’t used for evaluating coal combustion residues from enhanced mercury controls because “TCLP is not technically appropriate” where the disposal is not co-disposal with MSW.

Others have noted the limitations of the use of TCLP as an analytical method for predicting leaching potential of coal combustion wastes. Hassett notes that:

"The TCLP is often used in a generic manner for the prediction of leaching trends of wastes, although the intent of this test was for the prediction of leaching under co-disposal conditions in sanitary landfills. The application of acidic conditions to predict field leaching that can occur under a wide range of conditions may lead to false prediction of leaching trends. Additionally, conditions imposed on leaching systems by inappropriate leaching solutions may alter the distribution of redox species that would be found in the field and, in some cases with reactive wastes, 18 hours, as specified in the TCLP and other short-term leaching tests, may be an insufficient equilibration time. In order for a batch leaching test to be used, in determining potential for environmental impact . . . when being used with CCBs, the test must take into account the unique properties of the material, especially the hydration reactions of alkaline CCBs."

Hassett and Pflughoeft-Hassett, Evaluating Coal Combustion By-Products (CCBs) For Environmental Performance.

Because the tests are not designed for use with CCWs, they do not account for several typical reactions in CCWs under hydration. It has long been known that laboratory leaching procedures cannot precisely simulate field conditions nor predict field leachate concentrations. However, with careful application of scientifically valid laboratory procedures, it is possible to improve laboratory-field correlations and modeling efforts focused on predicting leachate concentrations. Id.

Hassett recommends the development of a selection of laboratory leaching procedures that more closely simulate field management scenarios, focusing specifically on technical and scientific variables such as the long-term hydration reactions that can impact leachate concentrations of several constituents of interest, the means by which water contacts the CCW in order to simulate the reduced permeability frequently exhibited in CCW utilization applications, the impact of pH and other CCW properties on the leachate and on resulting leaching; and the prediction of, and changes in, leaching over time. Id. Hassett recommends use of Synthetic Groundwater Leaching Procedure with a long-term leaching (LTL) procedure as a better predictor of leaching under field conditions. His work reflects that “[I]n many applications, the extended-time SGLP “has demonstrated trends significantly different from TCLP and other commonly used leaching protocols.”

The explanation for the differing results and trends between the extended-time SGLP and TCLP “can be explained by the fact that many commonly used leaching tests impose conditions different from those in a field environment on samples, and, thus, bias data in a manner leading to inappropriate interpretation for environmental impact. Elements most often affected include arsenic, boron, chromium, vanadium, and selenium.” Id.

The EPA Report on Characterization of Mercury-Enriched Coal Combustion Residues from Electric Utilities Using Enhanced Sorbents for Mercury Control, EPA/600/R-06/008 (January 2006) further underscores both the importance of utilizing proper test methods for characterization of these coal combustion wastes, and the trend towards increasing potential toxicity of such wastes as air pollution controls better capture metals entrained in and released during combustion of the coal. Among the observations of the agency were that “arsenic and selenium may be leached at levels of potential concern from CCRs generated at some facilities both with and without enhanced mercury control technology [and that] further evaluation of leaching or arsenic and selenium from CCRs that considers site specific conditions is warranted.”

With respect to the sufficiency of TCLP, EPA noted that leaching tests “focused on a single extraction condition” would not have allowed for an evaluation of the variations in anticipated leaching behavior under the anticipated field disposal conditions.

The reliance on total metals analysis and TCLP or SPLP data rather than on laboratory data that more accurately and adequately characterizes the leaching potential and “nonhazardous” nature of the wastes over the long-term, places both LGE and the Cabinet in a position where they cannot demonstrate with any degree of confidence that the containment for a disposal facility has been properly designed to address the potential for leaching constituents of concern.

A study of a bituminous fly ash disposal site revealed that several different leaching tests, both column and shake extraction, failed to predict the contaminants found in the monitoring wells. The study found that leaching tests both over predict and under predict concentrations of pollutants and that results should be field tested until the leaching characteristics of the particular ash are fully known. The study found that leach tests are unreliable field indicators "primarily because these tests are not designed, and should not be used, to predict exactly the concentrations of leachate components that will be found in the field."

The draft permit should be withdrawn until LGE provides the results of an array of appropriate longer-term leaching procedures applied to the individual and commingled waste streams, such as Kosson protocol, the LTL extended-time variant of the SGLP as described by Hassert, and sequential leaching tests such as that described by Ziemkiewicz that leach the CCB with samples of the water that will come into contact with the CCB (through surface infiltration of rainfall or groundwater) until the alkalinity is exhausted and the pH of the leachate returns to that of the encountered water. The LEAF protocol would similarly provide, as has been noted by EPRI and other researchers, much more complete and accurate information about the fate and transport of constituents in the coal combustion wastes than either of the single-point short-term batch tests TCLP or SPLP. Such dynamic testing under a range of conditions is needed in order to allow any meaningful prediction of the long-term leaching potential of these coal combustion wastes when used as fill in conditions where, as here, they are not isolated from rainfall infiltration and where the limited cap design all but assures the leachate will continue to be generated long-after placement and cell closure.

Failing to demonstrate the chemical characteristics of the waste and compatibility with cap and liner, and water that may come into contact with the waste, the applicant cannot demonstrate nor can the Cabinet find that, over the period of time during which the wastes will continue to leach metals and organics of concern prior to achieving chemical stability, that the performance standards of 401 KAR 30:031 will be met.


The draft permit proposes to issue a construction and operation permit allowing construction within 250 feet of intermittent streams on the condition that:

The landfill construction activities shall not commence in the permit boundary area designated in application APE20140001 until 1) receipt of the Water Quality Certification (certification) from the Division of Water, and 2) the certification is submitted to and accepted by the Solid Waste Branch in the Division of Waste Management. [401 KAR 45:140 Section 2].

Respectfully, the Cabinet is without authority to issue a conditional permit allowing the siting of a landfill until it has received and approved the water quality certification.

Among the requirements for engineering design of a special waste landfill are those of 401 KAR 45:110 Section 1, which requires a demonstration, prior to permit issuance, that the design complies with both the environmental performance standards of 401 KAR 30:031 and the siting standards of 401 KAR 45:130. The lack of an issued and approved water quality certification precludes issuance of a permit, and the draft permit should be withdrawn and re-proposed only when such certification, and compliance with these other requirements, has been demonstrated.


These comments are preliminary in nature, and will be supplemented prior to the close of the comment period. For the reasons stated herein, the draft permit should be withdrawn pending revision of the application to demonstrate adequate characterization of the Laurel Dolomite, compliance with the buffer zone requirements of 401 KAR 45:130 Section 1(3), issuance of water quality certification pursuant to Section 401 of the Clean Water Act, and full characterization of the long-term leaching potential and chemical characteristics of the individual and aggregated waste streams proposed to be landfilled.

Tom FitzGerald

Supporting KRC 
Thank you for your interest in Kentucky's environmental and public health. Individual contributions from donors across the Commonwealth make it possible for KRC to do its work every day, including advancing environmental, energy, and public health policies in Kentucky.
If you're interested in making an investment in KRC, visit

By Kentucky Resources Council on 08/31/2016 5:32 PM
« Latest News