What PPG 16 Says
The document advised that archaeological remains are a finite and irreplaceable resource and that their presence should be a material consideration in applications for new development. It accepted that development will affect archaeological deposits and that this effect must be mitigated. PPG 16 stressed the importance of the evaluation of a site for its archaeological potential in advance of development in order to inform future management decisions. This evaluation may involve non intrusive methods such as a desk-based study or archaeological geophysics and/or a more direct method such as trial trenching.
Following the results of the initial evaluation, PPG 16 offered two solutions for preserving any significant archaeological deposits found to be on a development site. The first, and explicitly preferred, method involves preservation in situ whereby the archaeology is left untouched beneath a new development through methods such as adaptation of foundation design and architectural layout of the proposed new development, or by raising the level of the development with made ground so that its foundations do not reach the archaeological horizon. Where nationally important remains are encountered this method of preservation is strongly preferred.
If preservation in situ is not feasible then PPG 16 permitted preservation by record. This involved archaeological fieldwork to excavate and record finds and features (thereby destroying them). This may involve a full excavation, further trenching in specific areas or an archaeological watching brief which involves an archaeologist monitoring groundworks for the new development and recording any finds or features revealed as construction continue.
Read more about this topic: PPG 16