Dear All,
As many previous threads have highlighted, most cities do not have scientific landfills and are used to simply dumping unsegregated waste. Of late,  things have started to change and many cities now practice segregation at source. With that success, and for various reasons including lack of alternative land parcel, availability of grants for scientific landfills, legal pressure to comply with SWM rules, policy push to deal with legacy waste, etc. cities have initiated managing legacy waste through bio-mining, bio-remediation, and even reuse the recovered material in agriculture and other construction. See the following two recent articles 

• Towards circular economy: What to do with legacy waste in India 
• A first in Punjab, Inert generated after bio-remediation of legacy waste to be used by NHAI in road construction 

I, however, haven't come across any piece that discusses the risks of reusing such recovered waste. Some of the risks I can imagine are

• high organic content (especially if used for filling)
• contaminated compost/ soil like material 
• Heavy metal contamination 
• small pieces of plastics (not sure if micro plastics is the right term)
• unknown contaminants 

I assume testing the waste would be a prerequisite to mitigate some of these risks, but I am not sure how equipped (and willing) local governments (and their consultants) are to follow due processes. 

The question is: How do we estimate and mitigate such risks? 
Relevant literature and experiences are always welcome.

Regards
paresh