The first thing Gwyneth McQuiston knew about industrial pig production was when she noticed a planning application for a farm near her home in Limavady, County Derry/Londonderry.
Gwyneth was puzzled. "I remember thinking why would anyone want to farm pigs? People don't farm pigs round here."
Always curious, Gwyneth decided to follow her nose.
But the journey she's been on since the beginning of her research has shocked her to the core. It's a story that has become bigger than she ever could have imagined.
"I never thought it would take us down the path of educating ourselves about Habitats Regulation Assessments and anaerobic digester plants," says Gwyneth.
Pig Business in Northern Ireland
Pig Business in Northern Ireland is a short film made by Farms Not Factories, which exposes the devastating impacts of mega pig-factory production units.
More pigs than people?
In 2013, Northern Ireland's Agri Food Strategy board set a target of increasing the country's breeding sow population to 53,000 by 2020. The board also recommended increasing intensive poultry production.
These targets come from Northern Ireland's Going for Growth strategy which aims to spur economic growth through intensifying agriculture.
Pigs have proved popular. There are currently 15 Pig Unit planning applications under consideration. 4 of these are for industrial scale farms such as the Limavady project.
The current applications would see more than 150,000 additional pigs each year being produced.
"The Limavady proposals alone aim to increase pig numbers in our area to 81,000. There are only 30,000 people in the town" says Gwyneth.
Terrified by the scale of the project, she helped to found the campaign group Stop Limavady Pig Factory.
The group has researched the planning application process in Northern Ireland, keen to get to the bottom of what the impact of all these pigs could be.
For starters, these pigs will have a lot of food miles. The group has discovered that feed for the pigs could be imported from soya plantations in South America. In another twist, they believe tails, snouts and trotters from the animals will be exported all the way to Chinese markets.
No one likes pig faeces
But the real problem is that this number of pigs will create an awful lot of slurry.
Some 1.3 million tonnes is expected to be produced every year for the whole of Northern Ireland. That’s the same amount that 12 million adult humans would produce.
Northern Ireland currently has 1.8 million people.
Untreated pig slurry contains high levels of ammonia. It contains 10 times more phosphates than cow manure.
If it's spread untreated on the land it can be dangerous to humans, plants and animals. If ammonia gets into rivers and lakes it can eventually cause eutrophication, a process which chokes off the oxygen supply in the water, killing fish.
Northern Ireland already has a serious problem with ammonia and nitrogen levels. Northern Ireland's current emissions are 4 times higher than the rest of the UK per head of population.
This is causing serious damage to waterways, wetland habitats, plants, trees and insects.
According to the Northern Ireland Environment Agency (NIEA), 98% of Special Areas of Conservation have exceeded critical thresholds for ammonia emissions at which ecological damage occurs.
"We already have such high levels of nitrate pollution, and there are no real plans for dealing with it," says James Orr, director of Friends of the Earth Northern Ireland. "We can't just add more. That's why we're calling for an immediate moratorium on planning applications."
Intensive farming and antibiotics
In addition, according to Farms Not Factories, approximately 30% of antibiotics used in the UK are given to pigs in factory farms.
More than half of these and other drugs are excreted in the animals' waste, creating antibiotic pollution in the environment. This increases the risk of antibiotic resistance developing, as often humans are given the same drugs as pigs.
I worry what will happen to this beautiful green landscape that I grew up with. Will the tourists still want to come if the water is poisoned and the wildlife is dying?Gwyneth McQuiston
If the thought of all that slurry being spread on a field near you hasn't already put you off your veggie bacon sandwich, let's talk anaerobic digesters.
The Agri Food Board has been promoting the use of anaerobic digester plants (AD) to deal with animal waste. These plants use microbes to break down crop waste and slurry. The energy produced is the source of much of what is being sold as green gas.
Because this energy is classed as renewable, AD plants receive a subsidy from Ofgem via the renewable energy tariff on utility bills. For the 69 plants currently operational in Northern Ireland, that is currently worth around £1.3 billion in payments.
But unsurprisingly, it seems that this is all too good to be true.
Not all the waste put into the plants is broken down - what remains is called digestate and this may be spread on the land.
There are reports of AD plants elsewhere in the UK leaking toxic gas or even exploding when they are not properly maintained. At the same time, AD plants have to be fed with other crops such as grass which uses up valuable agricultural land.
"Having one or two of these plants on a small-scale seems to make sense," says Gwyneth, "But now there is a sizeable subsidy involved, fat-cat investors from London have become interested. They are being run on a commercial scale."
Friends of the Earth Northern Ireland
James Orr and the Friends of the Earth team in Northern Ireland have provided invaluable support to the Stop Limavady Pig Factory campaign and others including at Newtownabbey since they started.
The team have given legal and networking advice. They've made submissions to the Environmental Audit Committee’s Nitrates Inquiry highlighting the potential danger in increasing pig and chicken production.
They've lobbied government agencies and international bodies, and produced a report on ammonia, Northern Ireland’s Dirty Secret.
Intensive agriculture and the associated problems with a massive increase in pig slurry cannot be the path to a healthy future for Northern Ireland.
If you're interested in following the campaign against the Limavady pig farm, you can visit their Facebook page. Your support will give people like Gwyneth a huge lift.