In my opinion plans for developing a new cemetery or urupa should include a sanitary survey to determine any possible effects on the groundwater - in particular whether there is likely penetration to deep groundwater because of conditions in the ground, but also to establish any effects there may be on the shallow water table.

Even though shallow water is generally acknowledged to be likely to be contaminated anyway by animal and other wastes, it may still be used against public health advice. Where people may be content to accept the risk inherent from grazing cattle, wild animals and birds and so on, they may not be so accepting of human remains.

The risks to consider might also include the possibility of re-emergence of contaminants into surface water such as rivers and lakes or estuaries used for recreational, food harvesting or farming purposes.

In such cases there may also be cultural issues to address. 

The TA should already have some idea if there is any use being made of shallow ground water locally.