17. (12 points)\\
As shown in the figure, the rectangular prism $A B C D - A _ { 1 } B _ { 1 } C _ { 1 } D _ { 1 }$ has a square base $A B C D$. Point $E$ is on edge $A A _ { 1 }$, and $B E \perp E C _ { 1 }$.\\
\includegraphics[max width=\textwidth, alt={}, center]{ba68dcdb-ba59-4e4a-a826-ca351fb7dd81-4_495_312_264_897}\\
(1) Prove: $B E \perp$ plane $E B _ { 1 } C _ { 1 }$;\\
(2) If $A E = A _ { 1 } E , A B = 3$, find the volume of the quadrangular pyramid $E - B B _ { 1 } C _ { 1 } C$.