Twenty years ago, an electricity cable under Ringsend Park sprung a leak and began to pump out cable fluid at a rate of 2,631 litres a month.
This went on for around four years, spilling in all 126,309 litres.
The Electricity Supply Board (ESB), which was responsible for maintaining the cables, failed to report anything to Dublin City Council. So it was never investigated.
That is until last year when ESB staff member Seamus O’Loughlin told RTÉ Investigates about 48 cable fluid leaks in the city that had not been reported.
Recent reports released by Dublin City Council under the Freedom of Information Act show exactly where those 48 leaks were, including spots across the city from Ringsend, to Heuston Station, to Inchicore.
ESB, the EPA and environmental consultants continue to disagree over the possible severity of the impact on the environment from these leaks, and even on whether or not the fluid leaked is hazardous.
Environmental consultants say that further investigations are needed to assess the environmental impact of the cable fluid leaks at 24 spots across the capital.
At Ringsend Park, the consultancy firm Golder, which was hired by ESB to assess the risks associated with the leaks, found that the fluid leaked could pose a potential high risk to the groundwater and a potential moderate risk to anyone occupying nearby basements.
A spokesperson for ESB said: “The identification of a potential risk in a preliminary site assessment does not mean that the risk is present but that further investigation is required to either confirm the presence or absence of the risk.”
The Story So Far
In June 2019, O’Loughlin told RTÉ Investigates that around 40,000 litres of cable oil was leaking out of underground electricity cables each year, mostly in central Dublin.
The leaks had not been reported for 20 years. Almost a million litres of cable fluid had leaked during that time, said O’Loughlin, in the programme.
After the show aired, the Environmental Protection Agency (EPA) launched an investigation.
The fluid leaked was hazardous, it said in a report in February this year. The agency told ESB to assess fully the situation.
ESB then commissioned several different environmental consultancy firms to carry out “preliminary assessments” of all 48 sites where there had been unreported leaks.
Those assessments have been done. Two locations were deemed potentially high risk: Ringsend Park and another on the South Quays near the Corn Exchange Apartments.
In both cases, consultants for Golder flagged not only a potential risk to groundwater and to the river Liffey, but also to people in nearby basements.
How Bad Could It Be?
The ESB spokesperson says that the fluid in the cables is linear alkylbenzene (LAB). It’s non-hazardous, they said.
The Golder report on the Ringsend Park site, though, says that that chemical hasn’t been designated as either hazardous or non-hazardous by the EPA.
“If a substance is yet to be reviewed it cannot be classified as non-hazardous,” says the report.
Another substance, mineral oil, was previously used in the cables and that’s hazardous, according to the EPA spokesperson.
“ESB have identified that the fluid lost from the cable leaks is often a mixture of mineral oil and LAB and therefore must be classified as hazardous,” they said.
Jack O’Sullivan, an independent environmental consultant and ecologist, says the two oils will likely have become mixed inside the cables – so the fluid leaking out would tend to be a mixture of LAB and mineral oil.
Not so, says an ESB spokesperson. “The Pembroke to Ringsend leak happened 17 years ago and the fluid involved, named LAB, is readily biodegradable.”
Says O’Sullivan: “That’s a little misleading.”
LAB might be biodegradable in certain conditions but he queries whether that would be the case underground without oxygen.
Some fluid may well have ended up in the Liffey as Dublin has lots of underground streams, says O’Sullivan. Even tiny amounts of pollutant can harm wildlife and sealife.
On The Clock
A spokesperson for ESB says that they have fixed all the leaks.
As of June 2019, there are new protocols to make sure any future leaks are reported to Dublin City Council, they said.
They’re liaising with councils on the recommendations from all the site assessments, they said. “We are due to progress onto the site investigation stage at a number of sites this month.”
The EPA spokesperson said that site investigations had been due to start in January this year.
So why the delay? An ESB spokesperson then said that they did start in January. “Site investigations started earlier this year in the Irishtown area but were impacted by Covid 19,” they said.
“As these investigations involve digging multiple pits in urban locations, it is not possible at this stage to accurately forecast a completion date,” said the ESB spokesperson.
ESB has replaced the cable that ran from Bedford Row to Sheriff Street, they said – the one that leaked at the Corn Exchange Apartments, and which was potentially high risk.
“A new fluid free plastic (XLPE) type insulation cable has been laid along this route,” says the spokesperson for the ESB.
Read together, the consultancy reports list another 22 sites scattered around the city that could pose a potential risk and require further investigation. Those are categorised at varying risk levels of low risk, low to moderate risk, and moderate risk.
Potentially high-risk locations should be prioritised first for further investigations, says the EPA spokesperson.
A spokesperson for the EPA says that the onsite investigations will include testing and monitoring surface water, and drilling holes in the ground to work out how much fluid has leaked and what needs to be done for remediation.
Samples need to be taken at the two places where leakages are at possible high risk of polluting the waterways or groundwater, say the reports.
Depending on those results, further investigations may include visiting the basements close to where the spills have been, because vapours from the leaked fluid could pose a risk to the occupants there, say the reports.
ESB was legally required to inform the council about the leaks, says a spokesperson for the EPA. Their failure to do so was a breach of section 14 of the Local Government (Water Pollution) Act 1977.
Dublin City Council will decide whether to prosecute ESB for failing to inform them of the leaks after they’ve worked out what the consequences have been of its failure to report, said a spokesperson for Dublin City Council.