28 May 1999

UP TO FARMERS TO REAP BENEFIT OF LERAP RULES

LERAP rules have been published and the implications

explained. Now, it is up to farmers and contractors to take

advantage. Peter Hill finds out how quickly sprayer and

nozzle manufacturers will get equipment rated to help them

make the most of the new approach

STANDARD 6m no-spray buffer zones applied to a number of crop protection materials can now be replaced with LERAPs – Local Environmental Risk Assessment for Pesticides.

The new scheme takes account of the degree of pollution risk posed by different application rates and the equipment used to apply them. Reducing the application rate of qualifying pesticides alongside a ditch, stream or other watercourse can trim the no spray zone from the new standard 5m to just 1m.

Application method can also be used to achieve the same end, since the scheme recognises the advances made in sprayer and sprayer nozzle design that have brought dramatic reductions in spray drift.

The latter is something for which sprayer equipment manufacturers, through their industry organisation, the AEA, have been lobbying. Now they have it, manufacturers, and eventually their customers, will have to pay for it.

"In some ways, we have been hoist by our own petard," admits Martin Baxter, European sales agent for the TeeJet range of spray nozzles. "Spraying equipment manufacturers have been banging on for some time that the 6m no-spray zone takes no account of the engineering controls available to regulate drift. With the new scheme now in place, we are rightly expected to come up with the goods."

In order for pesticides users to take advantage of this provision, nozzles and spray application systems claimed to offer drift control must be officially sanctioned. But since manufacturers learned the details of the scheme only a fortnight or so ahead of its introduction, there has been no opportunity for equipment to earn the necessary star ratings yet.

"We were inundated with phone calls in the days after details of the scheme were published," says Mr Baxter. "Its mostly from farmers wanting to know if and when TeeJet nozzles would be approved under the LERAP scheme. Its something we are now considering.

Low-drift nozzle

Likely candidates from US manufacturer Spraying Systems include the Turbo TeeJet, a conventional low-drift nozzle, the AI TeeJet, an air induction design, and the AirJet twin fluid system.

"Although we are keen to meet customer needs, we have to consider the likely demand for the star rating and balance that against the cost of accreditation," Mr Baxter points out. "If the majority of farmers decide simply to use application rate cuts to regulate no-spray zone widths, there is little point us going to the expense."

With the accreditation procedure costing £3000-4800 for each rating application and the cost of testing to obtain the necessary data at least as much if starting from scratch, it is not a decision taken lightly.

Brian Knight of sprayer maker Knight Farm Machinery agrees. "With air assisted sprayers such as our Air Sleeve now largely being bought by growers for specialist spraying operations, the sales volumes involved do not justify the cost of having the machine tested and rated."

Besides, he points out, with air assistance switched off, the Air Sleeve becomes a conventional sprayer on which LERAP-rated nozzles could be used to trim no-spray zones.

At Kverneland, sprayer product manager Graham Owen is confident that the companys Rau AirPlus air curtain sprayer will be put forward, especially if a search of existing data from trials in Germany and Hungary produces a good proportion of the necessary data.

"Im sure the AirPlus system would qualify for a two-star rating, possibly the top three-star," he says.

Hardi International applications specialist, Bill Taylor, believes the short answer to the question of whether the company will want to have its TWIN air-assisted sprayers LERAP rated is yes. And the same goes for selected nozzles.

"Generating the data for the TWIN system will be a lot more complex so I guess we will start with nozzles," he says. "Besides, nozzle selection will be the easiest engineering control option for sprayer operators."

Hardi already claims to have the edge on drift control with its Injet air induction nozzle and this will be the likeliest candidate with a good chance of securing a three-star rating.

Drift reduction

"But you could submit a conventional low-drift nozzle or even a standard nozzle at a coarse spray setting if that gave you sufficient drift reduction to warrant a rating," Mr Taylor points out.

John Sandys of Tecnoma sprayer agent LandMec favours the LERAP scheme in principle and is talking to his French supplier about having Tecnoma Aircharge air induction nozzles rated.

Lurmark is reviewing the data it possesses to determine what it needs for the DriftBeta air induction nozzle to be considered for a LERAP rating, says technical and export manager, John Castell.

Billericay Farm Services, which pioneered the air induction nozzle concept for crop spraying with its Air Bubble Jet, and twin fluid nozzle pioneer Cleanacres, is more upbeat still about LERAP.

Indeed, BFS submitted the first application for LERAP accreditation. "Since we only had drift evaluation data for the 03 Air Bubble Jet, we decided to have the full range tested and this provided all the data we needed for the star-rating application," says Simon Compton of BFS.

With droplet size evaluation apparently showing the Air Bubble Jets output at the smaller end of the scale compared with other air induction nozzles, BFS claims the nozzle is suitable for a number of application situations.

All the same, like all such nozzles, it relies on producing a coarser spray than a standard nozzle in order to control drift, and that has implications for efficacy in situations that demand a "fine" or "medium" quality spray.

"The answer is to use a different nozzle in LERAP situations where drift control must have priority, then switch to the best nozzle for the spraying task for the rest of the field," suggests Mr Compton.

That is a practical approach with rotating multi-jet nozzle holders fitted to the sprayer, and BFS has such a device configured to take the pencil-shaped Air Bubble Jets.

With twin fluid nozzles, points out Mark Curtoys of Cleanacres Machinery, the switch-over can be achieved at the press of a button.

"I see LERAP as another feather in Airtecs cap," he says. "One of the key advantages of the system is that the operator can alter spray quality by varying the mixing of liquid and compressed air. He could set-up the system for 80 litre/ha using a very fine spray, then switch to a coarse setting for areas of the field where LERAP would apply."

That is once the Airtec system earns its star rating, of course. Before which a lot of data must be collected.

"I am rather irritated that having subjected Airtec to a lot of tests and gathered a lot of information, the accreditation process demands either different data or data presented in a different way," says Mr Curtoys. "That will cost us a lot of money; but we shall go ahead, without question. The LERAP provisions on engineering solutions to drift control could have been designed for Airtec."

&#8226 The Pesticides Safety Directorate (PSD) will man a display explaining the workings of LERAP at the Cereals 99 event.n

EU-wide plan

All countries will have to comply with the EU Directive to control pollution of water by pesticides and the UK is some way in advance of most, says Silsoe Research Institutes Paul Miller.

"In the Netherlands, for example, there is a scheme with similar objectives to ours but using a different mechanism and means," he says. "We do need to make an effort to get a degree of commonality to save manufacturers some of the costs. But I dont think we shall ever get a harmonised standard."

With the UK LERAP scheme now in place, Prof Miller believes some EU countries could be interested in adopting a similar, if not the same, approach.

Compliance costs

Although manufacturers support the objectives of LERAP, they baulk at the cost of gathering and evaluating the data needed to earn star ratings for drift control.

They will pay £2800 for each star rating application based on data specific to drift evaluation; or £4600 where the assessment laboratory must interpret non-targeted data. In addition, an initial "check" fee of £200 per application is chargeable. The cost of collecting sufficient drift evaluation data from scratch for a specific application could be around £5000.

"That would not be so bad if we knew the same data could be used for similar schemes being set-up elsewhere in Europe; but that is not the case," says Mr Curtoys.

To earn a LERAP star rating spray equipment must record drift levels more than 75% of that from the reference – a 110deg flat-fan nozzle delivering 1.2 litre/min at 3 bar. Drift levels of 50-75% qualify for the one-star rating; 25-50% two-star; up to 25% three-star. Those ratings make a significant difference to no-spray buffer widths, cutting the statutory 5m buffer for a running ditch or watercourse to 4m, 2m and 1m, respectively.