In recent weeks, there has been a pungent pong sweeping over Splott and residents have been keen to trace the stinky source.
Quite a few of us reported the smell to environmental regulators in a quest to uncover the pongy point of origin.
So bad was the smell that one resident commented online that, despite loving living here, they weren’t sure if they could stick it for much longer!
Residents took to Inksplott social media to share their ideas on what was causing the smell, which was described as chemically / burning / sewagy (if that isn’t a word, it should be).
Suggestions ranged from the nearby sewage treatment plant to the Lamby Way food waste facility, the Celsa steelworks, the Viridor incinerator at Trident Park to the coast line and Rumney estuary itself).
However, some residents turned detective and followed their nose to Lewis Road, uncovering an interesting theory.
The waft was coming from the new Willows High School build on Lewis Road in lower Splott.
And, as it turns out, it’s true!
Confirmed by contractors Morgan Sindall in a newsletter to residents in the immediate vicinity of the new school build, and by the Cardiff and Vale Environmental Regulatory Service in a phone call to me this week, the smell is caused by the excavation work taking place on the site of the new school.
Splott Councillor Ed Stubbs has liaised directly with Inksplott over residents’ concerns and obtained further clarification after asking at this week’s groundbreaking event for some further information regarding the odour coming from the site. This is the information he received:
“Morgan Sindall have since confirmed that they are in communication with the pollution control team and have assured that all is in order and there is no risk to human health. Morgan Sindall provided the following update:
We are undertaking the following at present in line with the planning permission, environmental permits and CEMP (Construction Environmental Management Plan) for the scheme:
– Excavation and breaking out concrete obstructions from the old steelworks;
– Removal and remediation of ground as part of the process;
– The ground is contaminated in parts with hydrocarbons and it is when these are initially uncovered is where I suspect any potential smells are encountered;
– We are using hay and deodorising agent to help mitigate any potential release at source;
– Heavily contaminated sections are removed to a secure bed for further treatment;
– The remainder are moved to controlled stockpiles or testing and processing (i.e. crushing of hardcore and concrete);
– Relaying the material once criteria are met to formation level under the new school.
Here’s the text in full from the Morgan Sindall newsletter to residents:
Following the successful completion of the Enabling Works project we are pleased to announce that Morgan Sindall Construction have recently been appointed by Cardiff Council to undertake the main contract to deliver the new Willows High School.
The main contract commenced on 23rd September for a period of 108 weeks, with completion currently planned for October 2026
We will be constructing a new 8,800m² secondary school complete with all external works and associated infrastructure (new service supplies, sports pitches, hard and soft landscaping).
During the first three months of the project (October ‘24 to January ‘25) we will be undertaking the soil remediation and bulk earthworks operations.
Remediation is the process of removing or degrading contaminants within the soil to make it safe for the ecosystem. The site was a former heavy industrial site, namely the former East Moors Steelworks. As such the soil is contaminated with hydrocarbons and the ground full of the old concrete foundations, railway lines and other industrial debris. Our early activities therefore involve breaking out a significant quantity of historical foundations and excavating and treating the contaminated soil via a bioremediation process. We are also undertaking groundwater monitoring to ensure the aquifers beneath the site are not contaminated. All this work will be undertaken in line with our Remediation and Verification Report, a document that has been approved by the Local Planning Authority with involvement from Natural Resources Wales.
Please don’t be surprised to smell hydrocarbons/oils in the air coming from the site as these soils are excavated, cleaned and aerated at ground level before being re-used as in the ground as cleaner soil. We also apologise for any noise caused by us breaking out the historical foundations but we shall be carrying out noise monitoring to ensure we comply with the relevant British Standard, as agreed with Planning.
Cardiff and Vale Environmental Regulatory Service will provide me with a further update in coming weeks, but assured me in the initial phone call that there should be nothing harmful to residents, despite the bad smell.
*Further update – I received this explanation in an email:
Following our recent call your contact with Shared Regulatory services I can now advise that we have met with the Site contractors of the new Willows High School development on Lewis Road. The odours you are experiencing are part of the commencement works and land profiling remediation works on the site. Part of this when the soils on the site are excavated at certain depths can give rise to an initial release of odour. Onsite monitoring and mitigation measures are currently taking place on the site. Deodorising systems are in place and the methods of works have been specifically chosen in order minimise disruption as much as possible. All works are also being carried out inline with a permit issued by Natural Resources Wales.
We will continue to work with the Principal Contractors on the site regarding this matter and NRW will be monitoring compliance with the permit for the works as the development progresses.
So, it looks like the smell is here to stay during the initial phase of excavation, which is due to last until January 2025.