Logo for new startup

I need a logo designed for a new startup. This is for an environmental engineering project and i need the logo to be simple and effective.

I would require a portfolio to look at as the judgement will be based on bidders previous work. Also there are number of illustrations and graphic design which is also required. So i would prefer someone who can do both.

There are some other venture as well so there is number of other projects as well.

The project will be granted within next week. So there wont be any delays provided i find the right candidate.