Spraying of eco-toxic agrichemicals on farmland in Queen Elizabeth Park should be stopped, an environment group advocates, though Greater Wellington Regional Council is defending the practice.
The Queen Elizabeth Park Protectors said figures showed about 48 liquid tonnes of a mixture of chemicals were distributed by boom spray on the leased farm over the year, which was extra to the aerial spraying of herbicides on the farm last Labour Day, which the regional council regretted.
Emerald Glen organic farmer Peter Brooking, who requested the information, said the product labels showed almost every chemical to be eco-toxic, some deadly eco-toxic.
"Some are toxic to bees, some toxic to fish and aquatic life, some toxic to invertebrates and some toxic to terrestrial vertebrates."
But GWRC was satisfied the farmland and wider park was safe for animals and plant life as all chemicals used to control undesirable plants were properly licensed for specific usage and were applied by authorised spray operators in accordance with manufacturers' instructions as well as the regional council's own standard operating procedures, with a view to ensuring public and operator safety.
The park group, who noted the Reserves Act stipulated chemical use on park land should be minimised, said "this chemical dumpage should not be allowed to continue under the misnomer 'pasture renewal' for the purpose of fattening stock on public land".
It also said "the spraying was completely at odds with the vision of the Kapiti Biodiversity Project, which aims to protect and restore native flora and fauna in green spaces on the coast, including Queen Elizabeth Park".
GWRC said spraying in the farm to manage pest plants and renew pasture was confined to boom and backpack use (aerial spraying has stopped), with boom spraying the safest method because it was properly calibrated and controlled, and "the rate of application so light that plants quickly metabolise the chemical and there is absolutely minimal run-off to the ground as such, no effect to any surface water".
The park group was concerned about spray drift, stating it was recommended chemicals be applied in calm conditions or near calm conditions, but data from the MetService Paraparaumu weather station showed on a recent day of boom-spraying, August 2, northwest winds gusting up to 13 knots were recorded, and that it rained the next day, flooding the sprayed paddocks which the group felt "potentially endangered park aquatic life".
However, GWRC estimated only 1 knot of wind was recorded on site during the spraying, spraying was applied under strict conditions to prevent drift, and the spraying was done in dry conditions and completed about 12 hours before it rained, which "minimised any risk to aquatic life".
GWRC environment general manager Nigel Corry said GWRC's approach "has been to try to compromise over the use of aerial spraying, raise the issue of updating spray communication protocols and work with our farm licence holder on applying minimal amounts of chemicals on the land".
"Our role in the community is to manage the park in the interests of the broader community.
"Farming is a long time, valid use of the land provided for under the Parks Network Plan.
"Most observers of the changing nature of its landscape would note the positive impact that progressive management had had over the past year or so. Fewer weeds, cleaner pastures, no impact on the recreational side of the park, great co-operation over the recreational pursuits carried on by its neighbours.
"We are happy to continue to address this subject with the community to find ways to meet issues of mutual concern.
"We treat the land with respect, we do not indiscriminately dump chemicals, and we manage the land as good stewards in the general public interest."