Formal and informal
The formal rules that apply
For most infrastructural works relevant regulatory settings include multiple regulations. Some forbid or enable specific behavior in general, others instruct licensing authorities to apply the rules in individual cases and set the appropriate rules in a permit. In this situation discretionary space is often very limited.
The informal rules that apply
Therefore, all kind of content related issues are to be found in pseudo regulations (which are announced in formal rules), policy guidelines and policy documents (which are not announced in formal regulations). In most cases these informal rules limit the discretionary space of authorities. Informal rules indicate which decisions are most likely to be taken.