Trans- Ash Landfill Benton County, Tennessee Class II Disposal Facility

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1 1 Trans- Ash Landfill Benton County, Tennessee Class II Disposal Facility We have reviewed the Environmental Integrity report concerning the Trans Ash Landfill and believe there are several errors and/or omissions of significant facts in the document which distort the picture of environmental conditions at the landfill. Our response to groundwater issues is below. Private well impacts The EI report says there has been a determination of off-site damage to two private residential drinking water wells. In our opinion, there is still a lack of conclusive evidence that the Trans Ash landfill has impacted private drinking water wells. Mercury was detected in the Gibson well at levels above MCL. However, the EI report does not address the issue that the location of the well adjacent to a former gravel mine may play a role in the mercury level detected in the well. The Gibson well is bordered on two sides, and likely recharged, by two gravel mining ponds. The EI report did not properly address the issue of naturally occurring metals in groundwater in the area of the site. The geologic formation of the uppermost aquifer, the Camden chert, typically contains relatively large amounts of both iron and manganese oxides, and in an environment that has been significantly disturbed by gravel mining or well drilling, it is highly possible that metals will leach out of the geologic materials and be detected in the groundwater. The term naturally occurring refers to the idea that the source of the metals was from the natural geologic environment and not from an outside source, such as coal ash. This does not mean that elevated levels of metals will be detected uniformly in all areas of the same geologic formation. The level of disturbance of the soil and rocks is important, as the Trans Ash site is located in a former gravel mine. It is misleading to conclude, as the EI report did, that since the other 19 private wells sampled in the area did not show elevated Mercury levels, mercury cannot be naturally occurring in groundwater at the site. The other 19 wells were not located adjacent to the old gravel mining area. It is not clear if the second well refers to the abandoned well on the Gibson property. This well was abandoned prior to Trans Ash moving to the facility. According to Ms. Gibson, the well dried up when gravel mining pits were dug near her property. We sampled this well primarily to compare the mercury level in this well with the well the Gibsons were using. We attempted to purge the well, however, there was limited recharge and the results may have been impacted by well construction and the well casing and old piping in the well. The results showed a detection of mercury at mg/l, which is below the MCL for Mercury of mg/l. The sample results did show a high level of iron, 11.0 mg/l, however, this is consistent with the iron level in the Camden Gravel Co. well

2 2 and this may also be related to stagnant water and/or degradation of the old well casing and piping. We think it would be erroneous to conclude that the iron level in this well is due to impacts from coal ash at the Trans Ash landfill. Monitoring well sampling evidence of groundwater impacts The EI report cites data from the groundwater monitoring program at the site as evidence that waste from the landfill has impacted the groundwater. Much of this evidence is misleading. The report highlights all the highest levels detected at the site, but does not mention that the highest levels detected were detected prior to waste being placed in the landfill. For instance, the report says Arsenic was detected at 27 times the MCL, while not mentioning that this detection was from a sample taken prior to waste being placed at the landfill, and that arsenic has not been detected, at a detection level of mg/l, in monitoring wells at the site for the last five years. The EI report also misleadingly ignores other relevant sampling data. For instance, it mentions that the newly installed monitoring well, MW-5, showed a level of mercury of mg/l in the initial sampling. However, it does not go on to mention that in the two subsequent samplings, mercury levels were mg/l and non-detect, at a detection level of mg/l. The fact is that, in almost all cases, newly installed wells at the site have shown higher metal detections in the initial samplings and the levels have decreased over time. Trans Ash s consultants have explained that this may be due to disturbance of the hydrogeologic environment due to drilling and well installation. The report says that Trans Ash placed coal ash in the quarry prior to determining statistical background concentrations for CCW pollutants, including mercury. While it is true that while there may not have been enough data to do statistics on the background, the fact that the highest levels of metals came from a sampling prior to waste being placed at the site does lend some credence to elevated natural occurring background levels. The report also says that the piezometers installed at the site to characterize the metals which might be leaching from the coal ash were not drilled deep enough to sample groundwater conditions on top of the landfill liner and within the drainage blanket constructed of bottom ash. The piezometers were drilled to a depth of approximately two feet above the top of the liner in an effort to avoid any chances of penetrating the liner. It is our opinion that any water sampled from a piezometer at this depth should be indicative of dissolved metals leaching from the coal ash above the liner.

3 Finally, the document cites several TVA environmental assessment reports which we have not had a chance to fully review. The document says, TVA admits that levels of CCW constituents, such as sulfate and boron, in groundwater are associated with coal ash leachate from the landfill and quotes from one of the reports that these results indicate that groundwater quality in the Phase I landfill is likely being influenced from the Phase I landfill. Our response to this is that the groundwater monitoring reports submitted by both MACTEC, Trans Ash s initial consultant, and Triad, Trans Ash s current consultant, have never maintained that groundwater quality has been impacted by the landfill. They have cited evidence in geologic literature of the possibility of naturally occurring metals in the geologic formation and the sampling results prior to waste being placed in the landfill. With regard to sulfate, Triad s reports have repeatedly stated that although the sulfate is slightly elevated, it is present at levels similar to historical data and that they believe the sulfate in MW-4 is naturally occurring and not indicative of groundwater contamination from the landfill. They also cite literature which shows the sulfate levels are within a range of naturally occurring levels for the geologic formation. 3

4 Tennessee Valley Authority John Sevier Fossil Plant Class II Disposal Facility Tennessee Valley Authority (TVA) has a Class II permit (IDL # ) from DSWM to dispose of coal combustion waste generated at TVA s John Sevier Fossil Plant located in Hawkins County, Tennessee. Summary of Ground Water Monitoring for TVA John Sevier Ash Disposal Area The Class II Disposal Facility located at TVA s John Sevier Fossil Plant has impacted the ground water. The facility was placed into Ground Water Assessment Monitoring under Rule (7)(a)6 due to statistically significant increases of constituents over background on April 5, The facility remains in Ground Water Assessment Monitoring under Rule (7)(a)6. The monitoring system consists of one upgradient and five downgradient monitoring wells that are sampled on a semi-annual basis. The ground water samples are analyzed for inorganic Appendix II constituents as well as other constituents required by the permit. The results are compared to ground water protection standards (GWPSs) which are the higher of Maximum Contaminant Levels (MCLs) listed in Appendix III of Rule or statistically determined upper prediction limits (UPLs). If a MCL is not listed in Appendix III of Rule , then the DSWM used the tap water value in the Region 9 PGRs tables until the updated EPA Regional Screening Level Tables were published in December of The updated EPA Regional Screening Level Tables can be found at Statements from the report titled Thirty-one New Damage Cases of Contamination from Improperly Disposed Coal Combustion Waste February 24, 2010 and DSWM information In a report titled Thirty-one New Damage Cases of Contamination from Improperly Disposed Coal Combustion Waste February 24, 2010, Environmental Integrity Project and Earthjustice (EIPE) made several statements regarding the groundwater monitoring results for the Class II Disposal Facility located at John Sevier Fossil Plant. The following are statements from the EIPE document individually listed followed by information provided by the DSWM: 1. EIPE report states that aluminum is 8 times the highest secondary MCL. DSWM: There is no MCL for aluminum listed in Appendix III of Rule and the EPA Secondary Drinking Water Standard is listed as 0.05 to 0.2 mg/l (50 to 200 ug/l). EPA states at that EPA has established National Secondary Drinking Water Regulations that set non-mandatory water quality standards for 15 contaminants. EPA does not enforce these "secondary maximum contaminant levels" or "SMCLs." The highest level detected in a ground water well in the last two years has been 880 ug/l. The Regional Screening Level for tap water for aluminum is 37,000 ug/l. 2. EIPE report states the following regarding arsenic: a. Exceeds EPA National Recommended Water Quality Criteria (WQC) for human health; and b. That the groundwater monitoring reports from May 2009 show arsenic levels at 2.2 μg/l, more than 15 times higher than EPA s human health criteria for fish consumption.

5 DSWM: Arsenic was detected at 2.2 ug/l in one monitoring well, but the groundwater protection standard is 10 ug/l which is based on the MCL under the National Primary Drinking Water Regulations. The MCL is for protection of human health for drinking water. EIPE compared the concentration of arsenic detected in a ground water sample from a monitoring well to a standard for the maximum concentration of arsenic in fish tissue for human consumption. 3. EIPE report states that groundwater monitoring samples (May 2009, December 2008) show that cadmium levels exceed EPA s primary MCL in recent samples (May 2009, December 2008) from groundwater monitoring wells. For example, TVA measured cadmium levels at 6.8 μg/l and 6 μg/l, above the EPA MCL for cadmium of 5 μg/l. DSWM: In the past four years, cadmium has been detected at levels above the MCL of 5 ug/l three times in a downgradient monitoring well. Confirmatory sampling (which is proper regulatory protocol when a constituent is detected above a ground water protection standard) conducted within six weeks of the initial sampling did not confirm levels above the MCL of 5 ug/l In the April, 2011 Groundwater Monitoring Report, TVA outlines the investigation into the recent and erratic results for cadmium at well W31. Based on having split samples sent to three different labs, it is apparent that only one of the three labs is reporting high levels of cadmium. This is attributed to the various analytical methods employed and interference caused by the presence of elevated levels of molybdenum oxide and an increased flow of oxygen within the instrument can help control this interference. Tables 4 and 5 and Figure 1 from this report make this case quite clearly. Although there are still some discreprencies between the results from the three separate labs, it does appear that lab interference is the cause of the cadmium exceedances which are not confirmed by resampling or even split samples sent to different labs. This investigation is ongoing, but there is no clear trend or verifiable data to suggest consistent cadmium contamination at W31 or any of the downgradient monitoring wells in recent years. 4. EIPE report states that the groundwater monitoring reports from May 2009 show manganese levels at 5,700 μg/l, over 50 times higher than EPA s human health criteria for fish consumption. DSWM: Manganese was detected at 5,700 ug/l in one monitoring well as listed in the May 2009 TVA Report and it is above the Regional Screening Levels for tap water of 880 ug/l. EIPE compared the concentration of manganese detected in a ground water sample from a monitoring well to a standard for the maximum concentration of manganese in fish tissue for human consumption. 5. EIPE report states the groundwater monitoring reports from May 2009 show Boron levels of 18,000 μg/l are far above EPA Superfund Removal Action Levels (RAL) of 3,000 μg/l and 900 μg/l and exceed EPA s Drinking Water Health Advisory levels of 3,000 and 6,000 μg/l. DSWM: There is no MCL for boron listed in Appendix III of Rule Boron was detected at 18,000 ug/l in one monitoring well (W 31) as listed in the May 2009 TVA Report and was above the Regional Screening Levels for tap water of 7,300 ug/l. Boron has been and is above the Regional Screening Levels for tap water of 7,300 ug/l in the most recent sampling on April 20, 2011 in monitoring well W 31. The facility remains in Ground Water Assessment Monitoring under Rule (7)(a)6 due to statistically significant increases of constituents over background. However, boron is not listed as a constituent in Appendix II of Rule Rule (7)(a)6(iv) states in part that:

6 If one or more Appendix II constituents are detected at levels above the ground water protection standard, or statistically significant levels if the standard is based on background concentrations, the owner or operator must within 14 days of this finding give notice to the Commissioner of the finding and identify the Appendix II constituents which have exceeded the general ground water protection standard. The owner or operator also: Additionally, Rule (7)(a)7(i) states: Within 90 days of finding that any of the constituents listed in Appendix II to this rule have been detected at a statistically significant level exceeding the ground water protection standards defined under (7)(a)1 of this rule, the owner or operator must initiate an assessment of corrective measures. Such an assessment must be completed within a reasonable period of time. 6. EIPE report states that strontium was measured at 5,300 μg/l and exceeds EPA s health advisory level for strontium of 4,000 μg/l. DSWM: Strontium was detected at 5300 ug/l in one monitoring well as listed in December 2008 TVA Report, but does not exceed the Regional Screening Levels for tap water of 22,000 ug/l. 7. EIPE report states that sulfate was measured is 7 times higher than EPA s secondary MCL in groundwater wells. DSWM: There is no MCL for sulfate listed in Appendix III of Rule and the EPA Secondary Drinking Water Standard is listed as 250 mg/l (250,000 ug/l). EPA states at that EPA has established National Secondary Drinking Water Regulations that set non-mandatory water quality standards for 15 contaminants. EPA does not enforce these "secondary maximum contaminant levels" or "SMCLs." The highest level of sulfate reported in the December 2008 TVA Report was 1,300,000 ug/l. Sulfate is a parameter that is analyzed for as an indicator of contamination. 8. The EIPE report states that leachate from the CCW disposal area discharges directly into the Holston River. DSWM: In 1998, TVA installed a leachate collection system approximately 700 feet in length adjacent to the Holston river. This collection system has been recently lengthened by approximately 1800 additional feet making the total length 2500 feet. This collection system runs almost the entire length of the embankment. Once collected, the leachate is first pumped into the waste stabilization pond then pumped into the ash pond (surface impoundment) before being discharged under a NPDES permit. TVA is required to report semi-annually the amount of leachate collected and the analytical results of a sample of the leachate. The leachate is analyzed for the same constituents under the facility s groundwater monitoring program. Additionally, during , TVA installed a geocomposite liner system and leachate collection system over about half of the existing ash disposal area where disposal operations will continue. TVA anticipates that the remainder of the site will undergo closure in less than two years. A lined leachate collection pond was constructed and a gravity line then transports the leachate to the waste stabilization pond then it is pumped into the ash pond (surface impoundment) and discharged under a NPDES permit.

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