4.12. While monitoring plans should address all periods of development of the disposal project, they should also remain flexible given the different timescales associated with siting, construction, operation and closure of parts of the facility or the facility as a whole. Such flexibility should enable the integration of lessons learned from prior periods, adaption to new technology, and response to new regulatory requirements, design changes, etc., while at the same time maintaining data continuity and comparability. It should also enable the implementation of additional monitoring if concerns arise with regard to performance of the disposal facility. Moreover, international experience on monitoring activities should also be taken into account. Guidance specific to the conduct and objectives of monitoring at each of the three main periods of development of the disposal facility is provided in Section 6.