Potash slump raises stakes in Russia legal battle
* Eurochem seeks $800 mln from London-listed Shaft Sinkers
* Seeks similar sum in Dutch suit from main shareholder IMR
* Claim "nonsensical and fabricated" - Shaft Sinkers
* IMR says will make robust defence
* Eurochem stands by investments despite potash price slump
By Douglas Busvine
MOSCOW, Nov 12 (Reuters) - Engineering firm Shaft Sinkers has dismissed as "nonsensical" an $800 million claim brought by Russia's third-largest fertiliser firm over the flooding of a mineshaft that delayed a $4 billion potash project.
The claim by Eurochem pits its owner - tycoon Andrei Melnichenko - against a trio of oligarchs from ex-Soviet states who indirectly control Shaft Sinkers.
Eurochem filed for arbitration in October 2012 in France and Switzerland after terminating the contract in late 2011. It says Shaft Sinkers concealed evidence that the chemical sealants used would fail to keep groundwater out of the mine. Continued...