12.02.10Richard Goodwin, Environmental Engineering Consultant,

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During the past few months the USEPA has held a series of public hearings regarding the proposed classification of Coal Combustion Residue. Public comments end this month of November and USEPA is expected to render a decision by end of 2010. As of this writing no decision has been made public. My commentary reflects over thirty years of 'hands-on' engineering experience dealing with Power Plant Wastes -- particularly Coal Combustion Residue.

Coal-fired power plants generate three major waste streams: Bottom Ash [inert slag formed during combustion], Fly Ash [fine particulate matter -- removed from gas stream prior to venting] and Scrubber or Flue Gas Desulfurization [FGD] Sludge [precipitate formed during chemical removal of Sulfur Dioxide prior to venting]. The USA EPA has proposed two classifications for these materials -- hazardous or non-hazardous. Beneficial use of ash and FGD sludge [i.e. FGD by-product gypsum] is exempted; the former used as additive to construction materials and the latter used in Wall Board and Cement production [e.g. Tampa and Seminole Electrics]. Since approximately 40% of these wastes are used, if USEPA opts for hazardous waste classification -- beneficial use exemption notwithstanding -- the threat of potential litigation would defer end-users [e.g. LaFarge Cement, US Gypsum] from its reuse. Using asbestos lawsuits as a proxy, if 50,000 people were "exposed" to coal ash and at some time during their life found reason to file similar suits, then the potential liability to the industry is $25 billion. If the byproduct would be regulated as a hazardous material, that would cost industry $1.5 billion a year whereas if it is viewed as a nonhazardous material, it would run $600 million a year. This would result in higher construction material prices and increase electric utilities disposal costs and electricity generation rates.

USEPA's promulgation of their potential classification of coal-fired power plant wastes as Hazardous was prompted by TVA's Ash Spill [Kingston TN].

The TVA Kingston TN ash pond spill never should have happened. As I wrote over a year ago, TVA ignored geo-technical engineering consultants' recommendations to strengthen dike walls¹. TVA ignored geo-technical engineering consultants' recommendations to strengthen dike walls. Since May 2009, the EPA conducted on-site assessments of coal ash impoundments and ponds at electric utilities. The EPA (Feb. 4, 2010) released action plans developed by 22 electric utility facilities with coal ash impoundments, describing the measures the facilities are taking to make their impoundments safer. The action plans address recommendations from assessments of 43 impoundments and many of electric utilities have implemented these recommendations. For instance, one electric utility used a grout consisting of FGD sludge and fly ash to strengthen a dike wall; USEPA and state regulators accepted this methodology -- demonstrating the beneficial use of Coal Combustion Residues.

Land-filling Coal Combustion Residues offer a more manageable site option to achieve optimal geo-technical properties i.e. achieve liner-like permeability's by capitalizing on the material's inherent pozzolanic properties. Ponding of Bottom Ash requires a more rigorous geo-technical design and monitoring program. Beneficial Use of FGD By-Product Gypsum and fly ash for building materials are on-going commercial successes.

Sound engineering judgment supports the non-hazardous classification of Coal Combustion Residues -- based upon decades of operating experience.

References

1. Goodwin, R.W.; "Land Disposal of Coal Combustion Byproducts -- Upsets and Implications (Part 1)"; Energy Pulse Weekly; October 6, 2009

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Reader's Comments

Date	Comment
Len Gould 12.6.10	So where does the mercury go?
Richard Goodwin 12.7.10	Heavy Metals e.g. Hg, Pb, Cd etc are encapuslated within the Pozzolanic Matrix formed by reaction of Silica and Alumina in ash with Lime inherent to many coal and from lime based FGD systems - EPA could capitalize upon its data base of ash impoundment retrofits to propose guidelines for future pond - avoid the TVA accident while applying sound engineering practice - rather than mis-lable Caol Combusiton Residiues as Hazardous.
bill payne 12.7.10	Reality sadly argues 1 kWh = 3412.14164 BTU. More has to go in than comes out. http://home.comcast.net/~bpayne37/eprishumard/howard/howard.htm#scam
bill payne 12.7.10	So where does the mercury go? In to our lakes and streams. http://www.prosefights.org/nmlegal/prccrd/trip.htm
Malcolm Rawlingson 12.14.10	Bill, You didn't do that on a slide rule. Two decimal places (3412.14 ) is good enough. The best way to solve the coal residue problem is to build nuclear plants. No coal ash, no flue gas, no CO2. no SOX, no NOX,, no lead, no mercury, no cadmium. All waste kept safely right on site. Even Green Peace oughta like that. Malcolm

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