The recycling of coal combustion products (CCPs) into construction and agricultural related applications can reap substantial environmental benefits. These include:

- Waste stream reduction and associated reductions in requirements for landfill.

- Contribution to the conservation of resources such as gypsum, limestone and natural gas which would otherwise be used in cement production.

- Reduction in Greenhouse Gas (GHG) emissions from cement production of almost 1 tonne of CO2 per tonne of cement.

- Decrease in fertilizer application resulting from reduced losses

Land application of CCPs affects the bioavailability of nutrients and heavy metals by both acting as their source and sink in soils. Some of the CCPs are rich in S and Ca thereby acting as a source of these nutrients. They also control the transformation of N and P through immobilization and mineralization reactions. Similarly, CCPs can act as a source of heavy metals such as B and affect their reactions by altering soil solution chemistry including pH and ionic strength. Thus, CCPs can be used to manage the bioavailability of nutrients and heavy metals, thereby enhancing soil chemical fertility and mitigating metal contaminated soils.

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