I think you'll find the deadline for objections has passed. Try searching in Google, all the plans are available to inspect online.
Bob unless a planning determination has been made by the Local Planning Authority/committee, then you can make an objection right up until the Planning Committee put their bums down in the chairs to make a decision.
The date for submissions is an advisory one for the expedience of the Planning Officers so they can write a report of recommendations for the committee.
This article may help people to object to this proposal
http://www.barbel.co.uk/articlefr.htm Then go into technical articles and Guide to objecting to planning applications
It can be advantageous to objectors to place their objections as late as possible for possible legal challenges if the decision goes against those objecting
This proposal will have to have an environmental impact assessment associated with it. And that is where the weakness in the application will be if what you say about uping the weir by 2 ft is correct.
Just because it says it green energy doesn't always mean it won't have a serious impact on what are called "Material Conditions" under planning law.
EG Biofuel plants (green energy) omit to air CO2. CO2 omissions and other atmospheric pollutants through the burning of wood, all of which are Material Conditions under Planning Law.