French montpellier university is going to numerise between 20 000 and 50 000 raw sheet of paper (depending on the website you take the news) written by grothendieck after he quitted scientific community in the 90's.Apparently these seem to be mainly related to mathematic, philosophy and ecology. 
Unfortunately as they where originally not meant to be published there could be a huge work to do into translating them into formal  mathematic language, given the genius of the guy.
I suppose it dont totally answer to your question but there is certainly in all of these sheet enought ressources to publish new paper from grothendieck.
Unfortunately at the time of writting these line Montpellier university didn't provided any information on the way these data would be made available to public and the time numerisation process would take.
I should add that i'm not at all familiar with stackexchange pubslishing rule and Grothendieck work, I found this thread by trying to find ressources on the guy and thought that it could be a constructive answer to your question.

As it seem at this time no popular english scientific publisher wrote about this news the only reliable source I can provide you is in french [1]


Cordially

PS: I'm sorry if my answer dont comply with stackexchange publishing rule, don't hesitate to remove it if this is the case 

  [1]: http://www.liberation.fr/sciences/2015/06/17/les-gribouillis-d-alexandre-grothendieck-enfin-sauvegardes_1331465