  We study SPDEs with two reflecting walls $\Lambda^1$, $\Lambda^2$ and two
singular drifts $\frac{c_1}{(X-\Lambda^1)^{\vartheta}}$,
$\frac{c_2}{(\Lambda^2-X)^{\vartheta}}$, driven by space-time white noise.
First, we establish the existence and uniqueness of the solutions $X$ for
$\vartheta\geq 0$. Second, we obtain the following pathwise properties of the
solutions $X$. If $\vartheta>3$, then a.s. $\Lambda^1<X<\Lambda^2$ for all
$t\geq0$; If $0<\vartheta<3$, then $X$ hits $\Lambda^1$ or $\Lambda^2$ with
positive probability in finite time. Thus $\vartheta=3$ is the critical
parameter for $X$ to hit reflecting walls.
