Morgantown, West Virginia April 22, 2008 Innovative Mine Water Management Techniques for Submarine...
39
Morgantown, West Virginia April 22, 2008 Innovative Mine Water Management Techniques for Submarine Coal Mines of the Sydney Coalfield WVU Mine Drainage Task Force Symposium
Morgantown, West Virginia April 22, 2008 Innovative Mine Water Management Techniques for Submarine Coal Mines of the Sydney Coalfield WVU Mine Drainage
Morgantown, West Virginia April 22, 2008 Innovative Mine Water
Management Techniques for Submarine Coal Mines of the Sydney
Coalfield WVU Mine Drainage Task Force Symposium
Slide 2
Sydney CoalfieldSydney Coalfield Morgantown, WV Sydney, NS
Slide 3
Sydney Coalfield No.2 Sydney CoalfieldSydney Coalfield Port
Morien 1685 2001 More than 50 u/g mine produced over 500 million
tons Left behind voids for more than 50 billion gal of AMD And so
began the
Slide 4
1B Hydraulic System 1B System1B System Port Morien *Note 1B
Shaft location and No.26 location
Slide 5
1B System Geologic Structure A B Glace Bay Syncline Bridgeport
Anticline GeologicGeologic +128 asl -2760 bsl Port Morien
Slide 6
Stratigraphic Section Through Coal Seams Mined in the 1B
Hydraulic System (Section A - B through the Glace Bay Syncline) 100
m 75 m 23 m 30 m 40 m Sea level Glace Bay Reserve Mines Atlantic
Ocean A B Hub Seam-2.5 m Harbour Seam-1.8 m Bouthllier-1m
Backpit-1m Phalen Seam-2.3m Emery Seam-1.1m Emery Seam Phalen Seam
Harbour Seam Hub Seam Sedimentary Section Idealized Geology Between
Coal Seams Peat Swamp Lake/bay Lake/bay fill River Channelling Red
beds Soil Horizons (Siderite & Calcareous nodules common Peat
Swamp +128 asl -2760 bsl
Slide 7
Mining Methods within the 1B System Room and pillar Room and
pillar with pillar extraction Longwall
Slide 8
Flooding of the 1B System No. 26 lost to a fire In 1984 1B
Shaft pumps 1750 USgpm are shut down Flooding begins for the 8
directly connected mines Flooding soon follows for the 2 operating
mines
Slide 9
Lingan In-rushes Hydrograph 1B Hydraulic System
HydrographHydrograph PARAMETER 1 B Shaft pH7.4 Iron4.1
Alkalinity230 Sulphate951 Conductivity8760 No.26 floods down dip
flooding 1B Shaft Mine Water chemistry From 1B Shaft 1991 Pumps
prepared in 1B Shaft
Slide 10
SHALE Harbour Seam Atlantic Ocean Phalen Seam Coal Barrier
Flooded No. 26 Colliery Lingan Colliery Phalen Colliery Retreat
Direction 1100 ft 430 ft Coal Barrier 1100 B Emery sea Emery Seam
130 ft Flooding of Lingan Colliery starts Nov./92 Start the pumps
in the 1B Shaft !
Slide 11
1B Discharge 1B Discharge Nov. 1992 10 days of pumping
Slide 12
Lingan in rush and Mine closure Hydrograph 1B Hydraulic System
HydrographHydrograph PARAMETER 1 B Shaft ph3.9 Iron1,600
Alkalinity4.7 Sulphate4823 Conductivity13,800 No.26 floods Phalen
effects slow flooding no treatment ! down dip flooding 1B Shaft
Flooding rate increases New Mine Water chemistry from 1B Shaft Nov.
2002 Emergency WTP Phalen closes Pumps prepared in 1B Shaft Upgrade
Phalen Pumping Capacity & build WTP
Slide 13
SHALE Harbour Seam Atlantic Ocean Pillars >200 Barrier
Flooded No. 26 Colliery Flooded Lingan Colliery Phalen Colliery
Retreat Direction ~300 USgpm/panel 1100 ft 430 ft Emery sea Emery
Seam 130 ft Phalen Longwalls receive mine water
Slide 14
Mine water is Getting Close ! In mid 2002, monitoring boreholes
along the shoreline intercept bad quality mine water Less than 100
ft to overflow WHERE DO WE GO FROM HERE !
Slide 15
CBDC Developed a Stepped Approach to Deal With Rising Mine
Water (1)Late 2002, all focus is on mine water (2)The location,
quantity and mine water overflow date was calculated (3) All
surface water entrance points sealed (4) Established expert groups
to give advice (5) Additional boreholes drilled to sample mine
water chemistry and geology in upper areas (6) Began immediate
construction of an emergency WTP at the 1B Shaft site
Slide 16
1A Outfall projected to discharge by April 2003 at elev. +6 asl
No.1A Outfall at shoreline
Slide 17
MacKays Corner bootleg workings and AMD formation
BootlegBootleg
Slide 18
1B Shaft WTP 1B Treatment Plant and Settling Pond 1500 US gpm
capacity
Slide 19
1A Water Level -500 -400 -300 -200 -300 -100 0 No. 3
(1900-1915) No. 2 (1899-1947) No. 1A (1893-1927) No. 1BShaft No. 1A
Outfall Phalen Seam Outcrop No. 5 (1872-1938) -200 -100 +100 Coal
Pillars Coal Pillar Reserve Mines Glace Bay Outline of Mine
Workings Dominion No. 1A Outfall Atlantic Ocean B-172 B-171 B-174
B-175 January 2003 Less than 100 to overflow No. 1B Shaft
PARAMETERS No. 1B Shaft No. 1A B-171 B-172 B-175 pH units
3.63.37.47.77.5 Iron (mg/L) 2,0001,4500.56