Flying fly ash a concern

High winds, dry air and fly ash are a poor mix and residents of the area East of the SaskPower's Poplar River Power Station were not happy with the air quality on August 26.
Very high winds during the morning caused near white out conditions along the East side of the power plant as white fly ash blew off of the ash lagoons. The ash lagoons store the ash that is produced as a by-product of coal fired power generation.
The Poplar River ash storage system consists of three primary ash settling lagoons, a secondary settling lagoon and a polishing pond.
When the ash is removed from the bottom of the boiler it is mixed with water to form a slurry that is transported by pipeline to the lagoons that are situated south of the plant.
The lagoons are designed to move the water through the lagoons, utilizing gravity to separate the ash from the water; returning the water back to the plant for reuse.
The ash within the lagoon consists of approximately 80% flyash and 20% bottom ash.
The ash eventually dries in the lagoons and blowing can be a problem.
SaskPower representative Larry Christie said, "SaskPower attempts to maintain a layer of water over its ash lagoons in order to prevent ash from spreading from the coal-fired Poplar River Power Station."
SaskPower installed a sprinkler system at the lagoon to keep the ash wet to try to prevent blowing but at the time of the high wind, Christie said the sprinkler system was not operational as it was down for maintenance. "In late August, the sprinkler system that waters the ash lagoons at Poplar River Power Station was down for maintenance. A period of high wind caused some of the dry ash to spread beyond the power station property. "
Christie also said that reaching the capacity of one of the lagoons has also added to the problem. "The ash level in one of the lagoons has also reached capacity, and the ash is being dried prior to being surcharged." Christie explained that surcharging is where the interior of the ash lagoon is dewatered and allowed to dry so that earth movers can take ash from within the lagoon to build new containment dykes on top of the lagoon and increase the storage capacity.
"(The surcharging) compounded the problem caused by the sprinkler system maintenance." said Christie.
Christie said, "SaskPower has plans to add more ash lagoons and more sprinklers in an effort to better manage ash during periods of high winds. Until more lagoons and sprinklers are added, SaskPower will closely monitor the ash lagoons in an effort to keep the ash wet, especially during windy conditions. "
Local resident who asked not be named said that every time the winds reach 50 km or higher they have trouble with fly ash in the air. The resident has noticed the problem for a number of years and feels it is getting worse each year. The resident feels that their complaints thus far have fallen on deaf ears. Residents are concerned about their health.
Wikipedia says this about fly ash. Crystalline silica and lime are the major components of exposure concern. In and of itself, fly ash is neither toxic or poisonous, nor is it considered hazardous except when it becomes airborne. However, the fine crystalline silica present in fly ash has been linked with lung damage, in particular silicosis. OSHA allows 0.10 mg/m3, (one ten-thousandth of a gram per cubic meter of air).
The other fly ash component of some concern is lime (CaO). This chemical reacts with water (H2O) to form calcium hydroxide [Ca(OH)2], giving fly ash a pH somewhere between 10 and 12, a medium to strong base. This can also cause lung damage if present in sufficient quantities.
Janice Giroux, vice president of Community Health for the Sun Country Health Region said, "the Sun Country Health Region is not involved with the fly ash situation and no public health concerns have been indentified.'
Residents wonder why the ash isn't being recycled rather that being left in the lagoons. Around the world, fly ash is used in cement production and concrete products; for use in structural fills and embankments; for stablization of waste materials; for flowable fill and grouting mixes and as a mineral filler in asphalt paving.
Christie said that SaskPower does sell ash, "however, economics play a part in this and there are other competitors in the concrete/cement business." Christie also said that SaskPower makes much more fly ash that they are able to sell and "With respect to flyash from the Poplar River Power Station, SaskPower implemented a mercury capture technology which is making it unsuitable for sale to traditional market segments."