What is the environmental impact of using PFA grouts?
The range of grouts recommended by the UKQAA are such there should be little risk of a significant level of leachates from PFA grouts. As with concrete the leachates will be trapped by the hydration of the Portland cement and the pozzolanic interaction. However, during the construction process, any bleed water from the grout may have environmental consequences, especially if close to high quality aquifers. Reference should be made the the Generic Environmental Risk Assessment for the leachates associated with the PFA and some assessment of the leaching from the cement should also be made. A full environmental risk assessment may be required to obtain approval from the Environment Agency. We would suggest the BRE Environmental Code of Practice for Grouts could form the basis of such an assessment.