Dwalin, a loyal friend of the late Thorin Oakenshield, has come to assert Thorin's reign once again, but many of the dwarves in his party have fallen ill.
'Look, look! All of these dwarves are sick -- dying, I think! I cannot do another thing until I figure out what we can do to help them.
'I don't even know what happened to make them ill. How can I hope to cure them if I don't know how they came by this plague?
'Those foul Dourhands have really let this place crumble. Thorin would be livid if he could see it now! Full of poison and death.'
The dwarves of Dwalin's party came over the fields to the west of Frerin's Court when they arrived.
You should begin your search by following the road west to see if there is any evidence for the source of the plague that afflicts the dwarves.
Dwalin awaits word in Frerin's Court, east of the river where you examined the soil.
You should speak with Dwalin in Frerin's Court and let him know that the river itself seems poisoned by some sickly rot.