We introduce the dual mixed method for the heat evolution equation in a polygonal domain D with a random diffusion coefficient K and heat flux − → p = K♦ − → ∇u, ♦ denoting the Wick product. We prove a-priori error estimates for the semi-discrete solution ( − → p h , u h ) of lowest order of the dual mixed method having K-dimensional polynomial chaos expansion of degree N . Due to the reentrant corner of the polygonal domain D, appropriate refinement rules must be imposed on the family of triangulations in order to recapture convergence of order one in space.