Source: https://tendernation.io/opportunities/01a13b87-e2fa-7342-9977-953a5be65e73/cwm-rheidol-phase-2-works pending GB open procedure # Cwm Rheidol Phase 2 Works [The Coal Authority](https://tendernation.io/buyers/the-coal-authority) Estimated value Not stated Published 29 Jul 2021 Deadline Rolling deadline ## Who can bid - Open procedure Anyone can submit a full tender; there is no shortlisting stage. ## About this tender Abandoned metal mines are significant sources of metals pollution to surface waters, particularly as a result of polluted mine water discharges. Elevated levels of metals from these discharges, primarily zinc, lead and cadmium, can have a detrimental impact on the ecology of river systems, reducing fish populations and the diversity of invertebrate fauna. There are more than 1,300 abandoned metal mines in Wales polluting more than 600km of river reaches, making them the single biggest cause of water quality objective failures. The Cwm Rheidol project forms part of a wider programme of works, which are intended to reduce river pollution and help restore river health downstream, directly contributing to the sustainable management of natural resources in Wales as detailed in the Environment (Wales) Act 2015 and the Well-being of Future Generations (Wales) Act 2015. As a result of the above, National Resources Wales (NRW) commissioned The Coal Authority (CA) to assess the risks at a number of abandoned mine sites, with Adit 9 at Cwm Rheidol being the most significant and critical risk identified to date. Blow-out risk assessment reports have concluded that there is a potentially high risk of blow-out at Adit No.9 due to an existing blockage in, and progressive collapse of, the existing adit between the adit portal and rockhead. The principle objective of the Cwm Rheidol blow-out mitigation works is to reduce or permanently remove the risk of a minewater blow-out at Adit No.9. The Coal Authority on behalf of Natural Resources Wales (NRW) have undertaken a study to assess the risk and magnitude of a potential blow-out and concluded that there is a risk that up to 2,112m3 of water could blow-out of the adit portal at any time. A two phased approach is proposed to mitigate this risk; Phase 1 - The construction of a 2,112m3 capacity dry lagoon and engineered channel to convey any blow-out water from Adit No. 9 to the lagoon. Phase 1 is being carried out under the NRW framework Phase 2 - Draining down the adit and preventing future blow-out risk by introducing a permanent drain through the blockage in the adit and stabilising the roof. Phase 2 will be tendered under NEC4 contract conditions. Please note that this Prior Information Notice is for works to be undertaken as part of Phase 2 only. Read full description ## CPV classification Construction work for mining Source Find a Tender (UK) · Notice ocds-h6vhtk-02ce0e-2021-07-29T13:13:47+01:00 [View official notice](https://www.find-tender.service.gov.uk/Notice/ocds-h6vhtk-02ce0e-2021-07-29T13:13:47+01:00) Never miss a tender like this again Get AI summaries, deadline alerts and a bid pipeline for tenders matched to your business. Free to start. [Track tenders free](https://tendernation.io/register) [Buyer profile The Coal Authority: past awards and live tenders](https://tendernation.io/buyers/the-coal-authority) [Sector More Construction work tenders](https://tendernation.io/sectors/construction-work) ## More tenders like this [Building Minor Works · Derbyshire Support and Facilities Services Limited · 26 days left · 13 Nov 2026](https://tendernation.io/opportunities/01a15408-9087-7003-bd47-df7bc19d7ff7/building-minor-works) [DGT Helipad Design and Construction · Dartford and Gravesham NHS Trust · 28 days left · 16 Nov 2026](https://tendernation.io/opportunities/01a15408-969e-7140-a307-fe72fa7128be/dgt-helipad-design-and-construction) [Boiler Replacement Programme · Derbyshire Support and Facilities Services Limited · 26 days left · 13 Nov 2026](https://tendernation.io/opportunities/01a15408-9933-7015-97a0-37aa8d57c009/boiler-replacement-programme) [Construction of the Chiropractic Car Park, Treforest Campus · University of South Wales · 39 days left · 27 Nov 2026](https://tendernation.io/opportunities/01a15408-a995-70e5-b8b1-7c6a14e2e878/construction-of-the-chiropractic-car-park-treforest-campus) [Boiler chemical and Softener Services · Maidstone and Tunbridge Wells NHS Trust · 28 days left · 16 Nov 2026](https://tendernation.io/opportunities/01a1539a-d092-736b-88d2-6bdc251cddb6/boiler-chemical-and-softener-services) [Firefighting equipment installation work – Schaumlöschanlage (VE067), CVK, DHZC · Charité - Universitätsmedizin Berlin · 2 days left · 21 Oct 2026](https://tendernation.io/opportunities/01a15183-b929-71a2-940b-7b81046361a8/germany-firefighting-equipment-installation-work-schaumloschanlage-ve067)