1

Keynote Address: NOAMI Workshop, Winnipeg, Oct 26th 2006

Chair of Energy and Environment

Orphaned and Abandoned Mines: in pursuit of best practicein pursuit of best practice

Paul L Younger C.Geol. C.Eng. FIChemE FCIWEM FIMMM

HSBC Professor of Energy & Environment

Hydrogeochemical Engineering Research & Outreach (HERO) Institute for Research on Environment & Sustainability (IRES)

Newcastle University, UK. (paul.younger@ncl.ac.uk)

Keynote Address: NOAMI Workshop, Winnipeg, Oct 26th 2006

Chair of Energy and Environment

Orphaned and Abandoned Mines

= O&AM

2

Keynote Address: NOAMI Workshop, Winnipeg, Oct 26th 2006

Chair of Energy and Environment

Scope of talk … • Dimensions of the issue • Priority setting – policies, perspectives,

pragmatism • Community engagement – who, what and

why? • Partnership approaches – panacea or

pain-in-the-rear? • Towards best practices

Keynote Address: NOAMI Workshop, Winnipeg, Oct 26th 2006

Chair of Energy and Environment

Dimensions of the issue • Orphaned / abandoned mines:

– A lethal legacy?: long-term environmental impacts

– A precious patrimony?: community memory and the heritage ‘industry’

– both of the above? (in Europe – often yes; elsewhere … ?)

Dimensions of the issue

3

Keynote Address: NOAMI Workshop, Winnipeg, Oct 26th 2006

Chair of Energy and Environment

Environmental impacts of O&AM: pathways

• Air: dust-blown emissions: ingestion • Soil: direct ingestion / arable /

pastoral use; land stability • Water: rivers (dissolved phase and

sediments), aquifers, ecosystems, drinking water

Effects generally highly localised

Effects downstream: ≤ 100s of km Dimensions of

the issue

2

Keynote Address: NOAMI Workshop, Winnipeg, Oct 26th 2006

Chair of Energy and Environment

Dust and Land Stability Issues

Miami, Oklahoma (Tar Creek Superfund Site) Miami, Oklahoma (Tar Creek Superfund Site) –– PbPb/Zn /Zn orefieldorefield

Dune Dune bedformsbedforms on windswept, on windswept, finefine--grained mine wastesgrained mine wastes

Crown hole over deep Crown hole over deep mine roof collapsemine roof collapse

Dimensions of the issue

4

Keynote Address: NOAMI Workshop, Winnipeg, Oct 26th 2006

Chair of Energy and Environment

O&AM land instability: Impacts on Essential Infrastructure

DolphingstoneDolphingstone, Edinburgh, East Coast Main Railway Line, Edinburgh, East Coast Main Railway Line

CrownCrown--hole above ancient mine hole above ancient mine voids subject to recent change in voids subject to recent change in

water table positionwater table position

Dimensions of the issue

Keynote Address: NOAMI Workshop, Winnipeg, Oct 26th 2006

Chair of Energy and Environment

O&AM Stability Issues objectively dangerous

AberfanAberfan, , South South Wales, Wales,

2121--1010--1966, 1966, 144 people 144 people killed (116 killed (116 of them of them school school

children)children)

Dimensions of the issue

5

Keynote Address: NOAMI Workshop, Winnipeg, Oct 26th 2006

Chair of Energy and Environment

Environmental impacts of O&AM: frequency

• Air: an issue only with Pb, As, Hg, Cd etc • Soil: areal impact of pollution dependent

on markets (e.g. dairy herds etc) • Water: BY FAR THE MOST COMMON RECEPTOR AND VECTOR OF O&AM POLLUTION

Dimensions of the issue

Keynote Address: NOAMI Workshop, Winnipeg, Oct 26th 2006

Chair of Energy and Environment

Impacts of O&AM on water environment: surface waters

• Iron: most common pollutant (Mn, Zn, As often also mobile at pH ≈ 7)

• Acidity, low pH: an issue where weathering is near-surface:- spoil heaps, old tailings, shallow workings

• Other pollutants: e.g. SO4 – an issue where drinking water is abstracted downstream

Dimensions of the issue

6

Keynote Address: NOAMI Workshop, Winnipeg, Oct 26th 2006

Chair of Energy and Environment

Typical iron-rich (‘ferruginous’) mine water discharges

Ynysarwed, South Wales, UK - marginally acidic deep coal mine discharge, 250 mg/l Fe

Skinningrove, Cleveland, UK - two strongly alkaline ironstone mine discharges, both with 17 mg/l Fe

Dimensions of the issue

Keynote Address: NOAMI Workshop, Winnipeg, Oct 26th 2006

Chair of Energy and Environment

Major acidic discharge: Wheal Jane, Cornwall (UK), Jan 1992 (et seq.)

Dimensions of the issue

7

Keynote Address: NOAMI Workshop, Winnipeg, Oct 26th 2006

Chair of Energy and Environment

Acidic mine waters in a dry environment: Brugspruit, Witbank Coalfield, S Africa

Dimensions of the issue

Keynote Address: NOAMI Workshop, Winnipeg, Oct 26th 2006

Chair of Energy and Environment

Impacts of O&AM on water environment: ground waters

• Remarkably few recorded cases of pollution of major (i.e. potable supply) aquifers: – Major early example: Sth. Durham UK – Several other cases now pending in

Europe – Under-reporting to date: does it reflect

slow onset of obvious aquifer pollution after mine abandonment (decades)?

Dimensions of the issue

8

Keynote Address: NOAMI Workshop, Winnipeg, Oct 26th 2006

Chair of Energy and Environment

Water abstraction boreholes

Discharge into the sea

Evapo- transpirationInfiltrating

rainwater

Major recharge area

Mine water upflow

Runoff

Diminished recharge over glacial drift

Infiltrating rainwater

Piezometric surface

(confined)

Permian: Magnesian Limestone Aquifer and minor basal units

Glacial drift (Quaternary)

Coal Measures (Upper Carboniferous)

Sea or river

General groundwater flow direction

Water table / piezometric surface

KEY

Water table (unconfined)

Level of shallowest mine

workings

Water abstraction boreholes

Discharge into the sea

Evapo- transpirationInfiltrating

rainwater

Major recharge area

Mine water upflow

Runoff

Diminished recharge over glacial drift

Infiltrating rainwater

Piezometric surface

(confined)

Permian: Magnesian Limestone Aquifer and minor basal units

Glacial drift (Quaternary)

Coal Measures (Upper Carboniferous)

Sea or river

General groundwater flow direction

Water table / piezometric surface

KEY

Water table (unconfined)

Level of shallowest mine

workings

South Durham (UK): Aquifer Pollution From Underlying

Abandoned Mines Dimensions of

the issue

Keynote Address: NOAMI Workshop, Winnipeg, Oct 26th 2006

Chair of Energy and Environment

Spennymoor

Bishop Auckland

Shildon

Darlington

Stockton-on- Tees

¤ ¤

¤ ¤

¤¤¤

¤ ¤

¤ ¤

¤ ¤ ¤

¤ ¤ ¤

¤ ¤

¤

¤ ¤

Middlesbrough

Billingham

Hartlepool

Sedgefield

Ferryhill

¤ ¤ ¤ Newton Aycliffe

30.0 0 10.

00

100.00

100.00

300.00

¤

SO42- concentration contour (mg/L)

Water supply boreholes

Observation boreholes

Extent of the study area

Extent of the mine workings

Major settlements

100. 00

Spennymoor

Bishop Auckland

Shildon

Darlington

Stockton-on- Tees

¤ ¤

¤ ¤

¤¤¤

¤ ¤

¤ ¤

¤ ¤ ¤

¤ ¤ ¤

¤ ¤

¤

¤ ¤

Middlesbrough

Billingham

Hartlepool

Sedgefield

Ferryhill

¤ ¤ ¤ Newton Aycliffe

30.0 0 10.

00

100.00

100.00

300.00

¤

SO42- concentration contour (mg/L)

Water supply boreholes

Observation boreholes

Extent of the study area

Extent of the mine workings

Major settlements

100. 00

Predicted plume migration to 2010

Dimensions of the issue

9

Keynote Address: NOAMI Workshop, Winnipeg, Oct 26th 2006

Chair of Energy and Environment

Predictions of the calendar years in which specific public supply wells will exceed drinking

water limit (250 mg/l SO4) for first time

2019Hope House

2057Waterloo Plantation

2038Great Stainton

2029Stillington

2024Hopper House

Year in which SO4 concentration predicted to first exceed 250 mg/l

Public Supply Well

Dimensions of the issue

Keynote Address: NOAMI Workshop, Winnipeg, Oct 26th 2006

Chair of Energy and Environment

Heritage issues and O&AM

• Mining is probably the second (certainly the third!) oldest profession

• The earliest reliably-dated archaeological remains of mining keep getting ever more ancient (e.g. Bronze Age now widely- attested in NW Europe)

• Conserv