Introduction

Power Generation, Transmission, and Use

Markets, Regulation, and Oversight

Impacts of Power Generation and Transmission

Looking Ahead

Appendices

CEIR Report Map

PPRP Home

Maryland Power Plants and the Environment (CEIR-18)

4.6.4 CCB Marketing Activities

Use of Class F fly ash and bottom ash in cement and concrete has resulted in the beneficial use of over 80 percent of these materials as they are currently produced. The high demand for freshly produced CCBs prompted industry interest in a partnership to excavate and use previously disposed CCBs in cement manufacturers and ready-mix concrete industries. In 2009, the Maryland Environmental Restoration Group (MERG) developed a partnership with FirstEnergy’s R. Paul Smith Power Station in Williamsport, Maryland, to market its legacy ash pile, which had been accumulating since 1947 when the plant opened. Between fall 2009 and 2014, over 1 million tons of ash were mined from the pile. Although the plant was retired in late 2012, MERG continues to mine the ash pile, which is expected to be completely emptied of CCBs by 2020.

Maryland has a history of coal-fired power plants that stretches back to the late 1800s. For the majority of that time, CCBs were disposed in unlined fill sites that are now understood to have the potential to impact ground water. The success of the ash mining project at the R. Paul Smith disposal site could serve as a model to address other CCB pile and fill sites in Maryland by removing the CCB materials for sale to the concrete and cement industries. In addition, while CCB beneficiation facilities are not currently processing CCBs removed from former landfills, the potential exists for them to do so, further increasing the marketability of formerly disposed CCBs. Use of previously disposed CCBs in these kinds of manufacturing operations not only removes a potentially leachable material from the environment and converts it into a stable, monolithic solid, but also conserves natural materials that would otherwise be mined to support these manufacturing operations.

AES currently transports all of its FBC ash to surface mines for use as cover mixed with the site overburden. When used in this fashion, the alkaline components of the FBC are used to offset the acid mine drainage that can be produced by these mines. However, the mechanism by which FBC releases alkalinity is partial dissolution, a process that can potentially also release other constituents of the ash (such as heavy metals). PPRP currently supports monitoring of surface waters in the vicinity of these reclamation sites to track whether heavy metal releases are occurring.

Despite being underutilized currently, FBC ash generated at the AES Warrior Run power plant also holds marketing potential. This material contains levels of magnesium that make it unacceptable for use in cement manufacturers and ready-mix concrete industries. On the other hand, its free lime content makes it self-cementing when combined with water, which is useful for certain other applications. PPRP supports research and demonstration projects to develop methods of using this FBC ash and other CCBs to address the impacts of historic mining in Western Maryland (see Section 5.4).

Morgantown STAR Project

In early 2011, an innovative fly ash beneficiation project was licensed at the Morgantown Generating Station near Newburg, Maryland. The project was designed to thermally process fly ash using a proprietary staged turbulent air reactor (STAR) technology into a low-carbon, mineral admixture product suitable for beneficial use in concrete. The operation of the STAR facility diverts large volumes of unprocessed fly ash from landfills within the state and indirectly reduces greenhouse gas emissions associated with traditional concrete manufacturing.

Since commencing operation in January 2012, the Morgantown STAR facility has processed over 100,000 tons of fly ash from the Morgantown and Chalk Point generating stations. The entirety of the resulting fly ash product has been sold in ready-mix concrete markets in Maryland and Virginia. The STAR facility is continuing its ramp-up to annually process up to 360,000 tons of fly ash generated by the NRG Energy coal-fired power plants (Morgantown, Chalk Point, and Dickerson).