ABLE UK last night hit yet another stumbling block in its bid to scrap redundant "ghost ship" vessels in the North.

The Environment Agency said it maintained its objection to plans to convert the company's Teesside Environmental Reclamation and Recycling Centre (TERRC) at Graythorp, Hartlepool.

The conversion is vital for the work to take place.

The agency has been supplied with more details it asked for on the effect on wildlife of building new quays, a dam and a dry gate.

But last night, the agency said it remained unhappy there was insufficient information to assess the effect proposed dredging would have on birds at the internationally important Seal Sands wildlife site nearby.

The continued delays could mean Able will lose out on international scrapping contracts to Swan Hunter, based on Tyneside, which has applied for relevant environmental licences for such work and could have them in place as early as next month.

Swan Hunter turned its attention to ship-breaking and plans a link-up with Dutch company Ecodock after losing out on a major share of a £4bn aircraft carrier contract with the Royal Navy.

The difference between the two is that Swan Hunter does not require planning permission at its site, needed as a first step before licences are granted, whereas Able does.

Bob Pailor, an area manager for the Environment Agency, said it required "scientific modelling" to take place in order to prove the predicted environmental impact of the works, which was based on an expert opinion submitted by Able UK.

The modelling, carried out on computers, simulates how dredging could affect water and sediments in the Tees Estuary.

Mr Pailor said: "We are not opposed to this application in general terms, but we cannot agree to developments close to internationally important nature conservation sites, without having a full understanding of potential adverse effects.

"We are happy that many of the other issues we raised previously have been resolved by the company, providing a much enhanced environmental impact state- ment, but the impact of the proposed dredging is still a major stumbling block for us."

An Able spokesman said it had responded to the agency's request for back-up scientific modelling information. He said: "We hope the modelling information provided will give the agency the confidence they require and enable the proposals to be considered by the local planning authority at the earliest opportunity."