Modification notice
Modification of a contract/concession during its term
Section I: Contracting
entity
I.1) Name and addresses
Natural Resources Wales
Ty Cambria House, 29 Newport Road
Cardiff
CF24 0TP
UK
Contact person: Christian Clee
Telephone: +44 3000653000
E-mail: christian.clee@cyfoethnaturiolcymru.gov.uk
NUTS: UKL
Internet address(es)
Main address: http://naturalresourceswales.gov.uk
Address of the buyer profile: https://www.sell2wales.gov.wales/search/Search_AuthProfile.aspx?ID=AA0110
Section II: Object
II.1) Scope of the procurement
II.1.1) Title
Dispersed Alkaline Substrate Treatment Pilot Trials at the Parys Mountain and Cwm Rheidol Metal Mines
II.1.2) Main CPV code
71241000
II.1.3) Type of contract
Services
II.2) Description
II.2.2) Additional CPV code(s)
71241000
24962000
II.2.3) Place of performance
NUTS code:
UKL
II.2.4) Description of the procurement
Abandoned Metal Mines cause multiple failures of the Water Framework Directive (WFD) standards in Wales, with 1300 mines impacting over 700km of rivers. Cwm Rheidol and Parys Mountain are two out of the top five most polluting abandoned metal mines in Wales; Parys Mountain is unique, complex and the most polluting metal mine in the UK, whilst Cwm Rheidol is a mine complex with two point source discharges.
Previously, the only proven options available to NRW that will fit the challenging terrain have included High Density Sludge (HDS) treatment, HDS variants or electrochemical methods to successfully remove metals from water that is discharged from metal mines. These are expensive options (cost disproportionate in relation to clean-up benefits afforded) and unsightly in Special Landscape Areas to roll out at Parys Mountain or across the more typical metal mine deposits encountered across a large programme of mines.
There is an opportunity at both Cwm Rheidol and Parys Mountain to trial an innovative passive treatment system in Wales that has already been demonstrated at full-scale in Spain, in order to ensure we deliver value engineering treatment solutions for the public purse while ensuring that all the heritage, habitat and landscape constraints at both the Parys Mountain and Cwm Rheidol sites are adhered to.
Dispersed Alkaline Substrate (DAS) is a passive treatment system for acid mine drainage with high metal loading, developed over the last decade (Nieto, J.M et al 2013. Acid Mine Drainage in the Iberian Pyrite Belt. 1 & 2. Nieto, J.M et al 2019 & Martinez, N.M. et al 2019). The high treatment performance of DAS is based solely on inorganic dissolution of calcite (which removes Al, Fe(III), Cu and Pb) and Magnesium Oxide (which removes divalent metals), without reliance on bacterial sulphate reduction (typical for Vertical Flow Ponds that would require a much larger footprint of land ~1 hectare unavailable at Cwm Rheidol).
DAS achieves higher acidity removal than other conventional passive treatment systems, as metals accumulate intentionally in DAS. This high acidity removal rate reduces the footprint necessary to implement a full-scale DAS passive treatment system, which is also ideal for these mines with challenging terrain.
The trials will also include a tertiary treatment (Witherite/BaCO3) element of the solution that may be required to treat the sulphate that will not be removed by the DAS treatment.
This purchase will support with assessing the most appropriate long-term treatment, economically & logistically, for both of these mines.
II.2.7) Duration of the contract, framework agreement, dynamic purchasing system or concession
Duration in months: 24
II.2.13) Information about European Union funds
The procurement is related to a project and/or programme financed by European Union funds:
No
Section IV: Procedure
IV.2) Administrative information
IV.2.1) Previous publication concerning this procedure
Notice number in the OJ S:
2020/S 197-478663
Section V: Award of contract/concession
Contract No: 45374
Title: Dispersed Alkaline Substrate Treatment Pilot Trials at the Parys Mountain and Cwm Rheidol Metal Mines
V.2 Award of contract/concession
V.2.1) Date of conclusion of the contract/concession
21/09/2020
V.2.2) Information about tenders
The contract has been awarded to a group of economic operators:
No
V.2.3) Name and address of the contractor/concessionaire
Golder Associates (UK) Limited
Golder House, Tadcaster Enterprise Park, Station Road
Tadcaster
LS249JF
UK
Telephone: +44 1938836800
NUTS: UKE2
The contractor/concessionaire is an SME:
No
V.2.4) Information on value of the contract/lot/concession (excluding VAT)
Total value of the contract/lot:
/concession: 230 000.00
GBP
Section VI: Complementary information
VI.3) Additional information
(WA Ref:130898)
VI.4) Procedures for review
VI.4.1) Review body
High Court
Royal Courts of Justice, The Strand
London
WC2A 2LL
UK
Telephone: +44 2079477501
VI.5) Date of dispatch of this notice
20/04/2023
Section VII: Modifications to the contract/concession
VII.1) Description of the procurement after the modifications
VII.1.1) Main CPV code
71241000
VII.1.2) Additional CPV code(s)
VII.1.3) Place of performance
NUTS code:
UKL
VII.1.4) Description of the procurement
Modifications to the original contract due to unforeseen circumstances include:
- Relocation and re-design of treatment trial area at Parys Mountain
- Extension of laboratory based column trials
- Build an additional CaCO3 DAS + BaCO3 DAS treatment train using pine wood shavings in order to address the issues with treatment train 1.
- Decommissioning one of the treatment trains to concentrate efforts elsewhere
- Replacing of pipes to address the issue of mine water feed pipes clogging
- Installation of wind generator and additional batteries to the existing power supply at Parys mountain due to the pump not having sufficient power to run continuously
- Installation of an additional treatment train at the Parys Mountain trial
- Waste disposal including hazardous waste for the decommissioning of the trial at Cwm Rheidol
VII.1.5) Duration of the contract, framework agreement, dynamic purchasing system or concession
Duration in months: 36
VII.1.6) Information on value of the contract/lot/concession (excluding VAT)
Total value of the procurement: 366 908.00 GBP
The contract/concession has been awarded to a group of economic operators:
No
VII.1.7) Name and address of the contractor/concessionaire
Golder Associates (UK) Limited
Golder House, Tadcaster Enterprise Park, Station Road
Tadcaster
LS249JF
UK
NUTS: UKE2
The contractor/concessionaire is an SME:
No
VII.2) Information about modifications
VII.2.1) Description of the modifications
Modifications to the original contract due to unforeseen circumstances include:
- Relocation and re-design of treatment trial area at Parys Mountain
- Extension of laboratory based column trials
- Build an additional CaCO3 DAS + BaCO3 DAS treatment train using pine wood shavings in order to address the issues with treatment train 1.
- Decommissioning one of the treatment trains to concentrate efforts elsewhere
- Replace the Adit 6+9 pipe to address the issue of mine water feed pipes clogging
- Installation of wind generator and additional batteries to the existing power supply at Parys mountain due to the pump not having sufficient power to run continuously
- Installation of an additional treatment train at the Parys Mountain trial
- Waste disposal including hazardous waste for the decommissioning of the trial at Cwm Rheidol
VII.2.2) Reasons for modification
Need for additional works, services or supplies by the original contractor/concessionaire
Description of the economic or technical reasons and the inconvenience or duplication of cost preventing a change of contractor:
Due to the nature of the sites and the contract being a trial with the contractor holding the associated patents for the treatment schemes being trialled, this contract and its associated modifications can only be delivered by one contractor.
VII.2.3) Increase in price
Updated total contract value before the modifications (taking into account possible earlier contract modifications and price adaptions and, in the case of Directive 2014/23/EU, average inflation in the Member State concerned)
Value excluding VAT: 230 000.00 Currency: GBP
Total contract value after the modifications
Value excluding VAT: 366 908.00 Currency: GBP