[David Reichard (OP)]

I heard a report that thousands of batteries were buried near a major river,Would that create a risk of heavy metals going into the environment?

[evan_au]

Disposal of heavy metals in batteries and the solder of electrical circuits does pollute the environment.

At least they have started using lead-free solder in recent years (driven by EU legislation).
And recent electric vehicles have moved to lithium-based batteries rather than lead.
Hopefully these lithium battery packs are large enough and valuable enough to be worth recycling.

I heard that there is some EU legislation requiring manufacturers to take back products they manufacture at the end of life. That must surely force some attention to the costs of recycling?