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We present \textit{ab initio} multi-reference configuration interaction (MRCI) calculations of potential energy surfaces of HCCl in its three low-lying electronic states ($X~1A\prime$, $a~3A\prime \prime$ and $A~1A\prime \prime$) and for the spin-orbit coupling between the $X~$ and $a~$ states. The two singlet states become a degenerate $1\Delta$ state in collinear geometries. The potential energy surfaces are interpolated from 6075 MRCI energy points. The final surfaces are slightly adjusted using a coordinate and energy scaling approach. The $Te$ values of the $a~3A\prime \prime$ and $A~1A\prime \prime$ states are computed to be 2122.0 and 12209.8 cm$\mathrm{<mrow\; data-mjx-texclass="ORD">-1</mrow>}$, respectively. Vibrational energy levels of the three states of DCCl and HCCl taking into account the Renner-Teller effect and spin-orbit coupling are computed. The calculated vibronic energy levels are in good agreement with the available experimental values.