According to the website, they have been aware of it for a...

According to the website, they have been aware of it for a while. Although I would like to hear more if it is an issue.

Laws were passed in July 2017 from what I can tell. - So Old news somewhat. And I assume already covered by the BFS.

See Link:
http://www.peakresources.com.au/tanzania/

Extract from website:
"
Tanzania is politically stable and has a well-established mining culture, being the fourth largest gold producer in Africa. Existing transport infrastructure together with a low tonnage, high value product will enable cost effective transport from Ngualla to the deep water port in Dar es Salaam.
Regarding the July 2017 legislation changes we would like to refer to following 3 Act documents:

• No. 5 Natural Wealth and Resources (Permanent Sovereignty) Act 2017
• No. 6 Review and Re-Negotiation of Unconscionable Terms Act 2017
• No. 7 The Written laws (Miscellaneous amendments) and Act 2017

For further updates on the subject, we like to refer to the official Tanzanian Governmental website.
The planned total capital expenditure in Tanzania as defined by the detailed  BFS study and BFS Update is estimated at US $201 million including 15% contingency and 5% owners costs and we anticipate an annual operational expenditure of US $51 million."