Chapter 13 Pollution & the problems of Pesticide Washings

The Groundwater Regulations, which were enacted in response to the EC Groundwater Directive, is directed at controlling any pollution in groundwater, especially that used for drinking water. It has put a limit on pollution of 1 part of pesticide to 10,000,000,000 parts of water - equivalent to a drop in than Olympic size swimming pool!. The burying of waste packaging or getting rid of washings is now a serious problem.

When building the new Greenkeeper Centres at St Andrews, the head greenkeepers and I had many discussions on the problem of pollution and the wash bay. After a lot of discussion they came up with the following idea.

We built a concrete pad for the wash bay. It drained into a central point at which we placed a conventional 'bucket' silt trap. An underground pipe from the silt trap then led into a grass trap, basically the water flowing onto a fine mesh. The water was then piped to a soil soakaway. (The term soakaway is not now looked on favourably but soil soakaway describes it so clearly I will continue to use it)

The filtration of silt and grass cuttings is essential as the silt and grass clippings would block up the soil spaces and result in water running off rather than moving through the soil. It is important that the water goes through at least 10m of soil before it reaches a drain, burn or other watercourse. Normal soil contains many billions of bacteria and these will be effective in the breakdown of any residual contamination. On top of the soil area we have sown grass - this will show clearly if the pollution builds up, the grass will not look well!

The experience at St Andrews is that the system has been effective and the only real problem has been when the silt traps were not cleaned out with adequate frequency. When not cleaned out, the lifting and cleaning of the silt buckets has been a real problem and the carry over silt can block the soil soakaway.

The Greenkeepers at St Andrews over the past few years have been building washbays out in the golf courses draining into manufactured Reed Beds. Each consists of a concrete washbay leading into a series of three reed bads. So far, this has been very successful. Whether is would be as successful in the clay soils of the west of Scotland or not remains to be seen.

At all the wash bay areas, we have a container of sand for any large spillage, which may occur. We also have oil absorption granules for oil spills. If used, these will be taken away by an Approved Waste Disposal Contractor for disposal

Let me now detail our approach to pesticide application and pollution.

  1. We have a pest on our turf. Can we control it any other way? Spiking, fertilising, changing pH etc. If we can do this then the problem does not arise!
  2. When we decide to use a pesticide, we must read up on all the alternatives available and consider them not only from the point of view of efficacy but also for Health & Safety and Environmental effect.
  3. We must consider the equipment to be used : good well maintained equipment, nozzles to give non-driftable droplets, perhaps use of the Rogers Windfoil Type boom or equivalent, so that the task can be carried out efficiently and safely.
  4. We must only mix the amount required - this requires good calibration and a competent operator. If we only mix the amount required then we have less problems of disposal.
  5. All empty containers are washed into the sprayer 3 times and the containers disposed of appropriately..
  6. If we have any mixed product left in the sprayer, we must keep spraying until it is all used up on our crop. On a golf course or playing field there should be no shortage of extra crop. If we spray over the previously sprayed turf, we must ensure we do not go above the Maximum Dose Rate as stated on the label, or if the product is foliar in action, wash the product off the leaves.
  7. We then ¼ to ½ fill the tank with clean water and spray it out on extra crop or existing crop as in 5. above.
  8. We carry this out again - ¼ to ½ fill the tank with clean water and spray it out on extra crop or existing crop as in 5. above.
  9. If the outside of the sprayer is contaminated, it too should be washed out in the field.
  10. Further washings of the sprayer should be carried out in the wash bay constructed as above. Contamination at this stage is very low, dilution has taken care of that. Remember: the Solution to Pollution is Dilution!!
  11. I do not believe in using cleansers & cleaners on a golf course sprayer. The sprayer should be dedicated to one crop - turf. Often the cleaner is more environmentally polluting that the pesticide!!

If you need to spray glyphosate buy a sprayer and dedicate it to that purpose or bring in a contractor! All of us have heard horror stories of greens being wiped out through the sprayer not being adequately cleaned.

I have spent some time discussing this approach with members of staff from SEPA (Scottish Environmental Protection Agency) and EA (Environment Agency) who both agreed that this system was both practical and acceptable. However they emphasise that the responsibility is always with the creator of the pollution.

The above approach is much cheaper than the Waste2Water solution although many new courses are choosing this method as it deals with all the problem wiothout the hassle of the above.