Dr. David Wilson:

I thank Deputy Fitzmaurice for his questions. In regard to how much carbon will be taken in, we know that 6 million tonnes of CO2 is released into drains. Rewetting, if done successfully and maintained over the year, will shut that down. We will, therefore, make avoided losses or saving 6 million tonnes of CO2. If we can get the right plant communities in and maintain the water, we can flip the system so it becomes a sink. The numbers vary and I am not being vague but it will depend on the sites. If we can get a good site that remains wet, we can certainly look for anything between 0.5 and 1.5 tonnes of carbon - not CO2 - per hectare per year, which is not nothing, as they say. It is a sizeable amount. If we were moving towards a system where we have recreated the functions of the peatlands that resemble a natural or undrained site, that figure would lower the amount to something like 0.3 tonnes of CO2 carbon. Initially, when rewetting starts the system becomes very vigorous whereby a lot of carbon goes in and new plants come in. So one is looking at anything between 0.5 to 1.5 tonnes of CO2 carbon, not CO2. One must multiply the amount by 3.66 to get the amount of CO2. One has made the savings of 6 million tonnes of CO2 and then one has the addition of the sequestration, provided the site remains wet, particularly during the summer months.

On the second question, the Department has identified at least 40,000 ha of grassland on organic soils. The point is that because it is on organic soils it is not sequestering but releasing carbon. That is reflected in our submissions to the national inventory reporting 8 million tonnes of CO2 per year. It is not sequestering carbon. If it was mineral soil then, there might be a small amount of carbon sequestered by the mineral soil or grassland.

The Deputy's third question was on whether a 30-year period is used by Bord na Móna. That is a number used to give us a chance to flip the system so we are not expecting results immediately. What we are finding in terms of greenhouse gas emissions is that if rewetting is done successfully and maintained, the system flips back quite quickly. Methane emissions are always an issue in the early years because a lot of organic matter has been created for the microbes to work on, the bog has been rewetted and there is no oxygen in the system and there is, therefore, a flush and spike of methane in the early years. The thinking, and it is only thinking, is that in 30 years that methane spike will have cleared itself and the system will be more akin to a natural site in that it will take in a small amount of CO2 every year but only releases a small amount of methane. A 30-year period probably reflects that but nobody really knows. We do not have many long-term rewetting sites, certainly not in Ireland, where we can go in and identify what happens in terms of the greenhouse gas dynamics. To me, 30 years sounds reasonable and is not totally short term. If we are looking very long term, we would be looking at hundreds of years. I agree with Dr. Flynn that 30 years is something we could look at and work with.

The Deputy's described turf cutting as inconsequential. It is inconsequential only because the Environmental Protection Agency, EPA, does not know what is out there. When the EPA gets a better handle on what is out there and how much it is affected, the 400 ha figure will increase, possibly by a large amount. This will be dependent on better land use mapping and better use of remote sensing data. I am sorry to tell the Deputy that turf cutting is not inconsequential.