The β− decay of 34Mg was used to study the 34Al nucleus through γ spectroscopy at the ISOLDE facility of CERN during the IS530 experiment
in 2012 at LA2 and 2015 at the ISOLDE Decay Station. The 2012 run marked also the birth of the ISOLDE Decay Station, which will be briefly discussed during the presentation. Previous studies identified two β-decaying states in 34Al of spin and parity 4- and 1+, dominated by normal and intruder configurations respectively. Their unknown ordering and relative energy were a subject of debate for the placement of 34Al inside or outside the N=20 ’Island of Inversion’. Recently published results from the IS530 experiment clearly settle the dispute and will be presented during the seminar. Large scale shell-model calculations with the recently developed sdpf-u-mix interaction are compared with the new data and used to interpret the mechanisms at play at the very border of the N=20 “Island of Inversion”.