The ruling on whoever doubts concerning the Stones falling into the Basin (at the foot of the Pillars)
Question:
What is the ruling on whoever has a doubt that some of his stones did not fall into the basin?
Answer:
Whoever has doubt, then he must complete it. He should take some stones from the ground from where he is in Mina and complete the stoning with them.
Shaykh `Abdul-`Azeez Bin Baz
Fatawa Islamiyah Darussalam Vol:4 no.249