Recently, highly--charged ions have been isolated in a novel compact Penning trap designed to capture ions extracted from the NIST electron beam ion trap (EBIT), opening a new avenue of manipulating ions isolated in a controlled environment for a variety of studies. The unique architecture of this extremely compact Penning trap facilitates optical experiments with stored ions, as well as ion counting via position-sensitive or time-of-flight micro-channel plate (MCP) detectors. As a first demonstration, Ar13+ ions are captured in one of the two fine structure levels forming the lowest lying states. The lifetime of the metastable 1s22s22p 2P_3/2 state is measured by counting the 441 nm photons emitted in the spin-flipping (M1) decay to the ground state. This work presents the novel Penning trap, the apparatus deployed at the NIST EBIT, techniques employed for ion capture and storage, and a new measurement of the lifetime of the metastable 2P_3/2 state.