The NFU has accused DEFRA of ignoring good science and burdening the farming industry with unnecessary cost as it prepares to roll out a new Nitrates Action Programme.

At a meeting with juniorDEFRA minister Phil Woolas on Tuesday (8 January), the union spelt out its eight "red lines" which it says must not be crossed as the government draws up the details of the NAP.

It is especially concerned that DEFRA is planning to impose much longer closed periods for slurry spreading and wants farmers to invest in bigger storage tanks.

Under the existing NAP, which came into force in 2002, livestock farmers are subject to a 2-3 month closed period and have to have 2-3 months of storage available.

But under the new NAP it is expected that farmers will have to respect a 3-5 month closed period, depending on soil type and rainfall levels, and will have to provide 5-6 months' slurry storage depending on whether they keep cattle or pigs and poultry.

"The link between closed periods and storage capacity has been broken," said NFU head of policy services Andrew Clark. "At the extreme we could find a pig producer in an area of low rainfall and heavy soil with a three-month closed period and a six-month storage capacity."

The NFU is also concerned that DEFRA plans to designate at least 70% of England as a Nitrate Vulnerable Zone (NVZ), compared with just 4% in Wales and 15% in Scotland. It estimates that around 5000 dairy farmers will be caught by the rule changes and will have to spend hundreds of thousands of pounds to comply with the new programme.

Mr Clark also complains that the plans for England are far tougher than those that have been introduced in Northern and Southern Ireland.

But the chances of securing a softer outcome are slim as DEFRA is under intense pressure from Brussels to strengthen and extend the NAP. It has been threatened with court action and fines if it fails to do so.

Despite this, the farming industry questions the whole rationale. "The existing NAP is already delivering in terms of water improvement," said environment consultant Michael Payne. Studies of Environment Agency data show that many rivers have seen marked declines in nitrate levels - especially those running through NVZs. For example, the River Trent has seen a 20% drop since 1990, while the River Nene has 15% less nitrates.

This Mr Payne attributes to the drop off in farmers' use of nitrogen, the development of more efficient plant varieties and the fact there are fewer farm animals around. "In our view there is no case for a tougher NAP."

NFU's eight red lines

1. The area of England designated as Nitrate Vulnerable Zone should not exceed 70%. Currently only 55% is NVZ, although DEFRA has hinted at 100% as a way of achieving simplification
2. Some of the current NVZ - about 6% - is incorrectly designated. Farmers in these areas should not face any new restraints than under the existing Nitrates Action Programme
3. The closed period for slurry spreading should not extend beyond 1 December each year
4. Slurry storage capacity should reflect the circumstances of individual farms and be linked directly to the length of the closed period
5. There should be no requirement to grow a cover crop on arable land not drilled to cereals in the autumn, (as DEFRA is seeking), as this is not even mentioned in the Nitrates Directive
6. The implementation of the new NAP should occur four years after its publication, not two years as DEFRA is suggesting, to give farmers time to invest in extra slurry storage
7. Grants of at least 40% must be made available to help farmers meet the cost of this investment - as is the case in Ireland - or agricultural building allowances should be maintained
8. A derogation to allow livestock farmers to apply up to 250kg of organic nitrate per hectare rather than the 170kg N/ha basic rate must be applied for at the first opportunity.