https://www.theguardian.com/politics/2017/mar/30/great-repeal-bill-will-create-sweeping-powers-to-change-laws-after-brexit
[edit: I've just seen that the white paper is available. Maybe it addresses my points below]
Such control.
A lot of EU laws* (like, a really big lot) can't just be transferred into UK law because they defer authority to other EU regulatory bodies.
This gives us 3 options:
1) Mutually recognise decisions by those EU bodies. This doesn't really work, since the UK would no longer be able to request judgements from these EU bodies without some very clever negotiations - for which there is no time. Plus, mutual recognition is literally the opposite of 'taking back control'.
2) Create a parallel UK body to perform the role of the current EU body. e.g. our own pharmaceutical regulatory authority. This is possible and in some cases necessary, but it would require a vast expansion of our public sector... not happening with this government!
3) Burn them! A lot of laws will just be abandoned as unsupportable since they are too heavily reliant on the EU. It'll be done using the Henry VIII powers to dispose of them with little or no parliamentary oversight. Where absolutely necessary, we'll set up a sovereign UK agency that consist of a handful of civil servants rubber stamping UK versions of the judgements from EU bodies (kinda a mix of 1 and 2). This provides an illusion of control, but will be a disaster when UK citizens/businesses ask the rubber-stampers to make decisions on issues that only (or differently) affect the UK.
I think that a lot of things are going to be stuck in regulatory limbo as the EU laws can't apply, while the UK is unable to legislate on its own due to no relevant authority being available, or said authority being little more than a vacant address with a sign saying "under construction, come back soon!"
* Most of these "EU laws" are already UK laws because of the way that implementing EU directives works, though some EU regulations are applied directly.