1. Water Quality Changes Over Time in Above-Drainage Upper Freeport and Pittsburgh Coal Mines in West Virginia Ben Mack, Jeff Skousen, Louis McDonald, and Dorothy Vesper West Virginia University

2. - Major pollutant - Pyritic rocks

3. Mine type Above-drainage vs. Below-drainage

4. Younger (1997) Below-drainage - 10 - 40 years Below-drainage - 10 - 40 years - Type 1 - initial flush of mine - first 10 years after mine closure - Type 2 - continued pyrite oxidation Below – drainage mines Below – drainage mines - 25 years between samples - pH from 3.0 to 6.1

5. Above – drainage mines Above – drainage mines - 25 years between samples - pH from 3.0 to 3.5 Lambert and Dzombak, 2000

6. Annual % decrease of 2 and 3% from the previous year

7. Determine changes in acidity concentrations of 40 above- drainage, underground mines over 38 years using decay rates Determine changes in acidity concentrations of 40 above- drainage, underground mines over 38 years using decay rates

9. Historic sampling 1968 - EPA - 555 sites 1968 - EPA - 555 sites 1980 - WV DNR - 20 sites 1980 - WV DNR - 20 sites 2000 - WVU - 40 sites 2000 - WVU - 40 sites 2006 - WVU - 40 sites 2006 - WVU - 40 sites Graphs of acidity vs. time for 6 Pittsburgh and 34 Upper Freeport (UF) sites Graphs of acidity vs. time for 6 Pittsburgh and 34 Upper Freeport (UF) sites

10. Acidity collection

11. Compare to T&T #2 Compare to T&T #2 - Closed in 1996 - Different decay rate?

12. Sitesn1968-19801980-20002000-20061968-2006 Pittsburgh6-83%-58%87% -74%

13. Sitesn1968-19801980-20002000-20061968-2006 UF > 160012-58%-44%10%-81% UF 600-159910-43%-35%5%-79% UF 0-59911-23%-4%-42%-70% Increasing UF144%47%-31%46%

14. Sitesn1968-19801980-20002000-20061968-2006 UF > 160012-58%-44%10%-81% UF 600-159910-43%-35%5% -79% UF 0-59911-23%-4%-42%-70% Increasing UF144%47%-31%46%

15. Sitesn1968-19801980-20002000-20061968-2006 UF > 160012-58%-44%10%-81% UF 600-159910-43%-35%5%-79% UF 0-59911-23%-4%-42% -70% Increasing UF144%47%-31%46%

16. Sitesn1968-19801980-20002000-20061968-2006 UF > 160012-58%-44%10%-81% UF 600-159910-43%-35%5%-79% UF 0-59911-23%-4%-42%-70% Increasing UF 144%47%-31% 46%

17. Groups n 1968198020002006 ---------mg/L as CaCO 3 ------- Pittsburgh 6 2398574412447 UF 34 1351598379265 Groupn1968-19801980-20002000-20061968-2006 Pitts. 6 -6.3%-1.4%1.4% -2.1% UF 34 -4.6%-1.8%-5.0% -2.1% % decrease of acidity per year

19. % of initial concentration vs. time (exponential decay) Exponential decay: C/C 0 =e -kt C/C 0 =e -.02t C/C 0 =e -.05t C/C 0 =e -.10t

20. Pitts. exp. decay constant (k) = -0.044 Estimated initial acidity = 9,113 mg/L as CaCO 3 (3.86 relative acidity) 2006 sampling 1968 Sampling

21. UF exp. decay constant (k) = -0.054 Estimated initial acidity = 5,413 mg/L as CaCO 3 (4.01 relative acidity)

22. Acidity at time of closure = 1,128 mg/L as CaCO 3 T&T exp. decay constant (k) = -0.104 Increased decay rate due to first flush

23. Conclusions Pittsburgh and UF mines showed a 2.1% annual decrease in acidity Pittsburgh and UF mines showed a 2.1% annual decrease in acidity

24. Pitts. mines Pitts. mines - Pitts. decay rate constant = -0.044 - Estimated initial acidity = 9,113 mg/L as CaCO 3 (3.86 relative acidity) UF mines UF mines - UF decay rate constant = -0.054 - Estimated initial acidity = 5,211 mg/L as CaCO 3 (4.01 relative acidity)

25. T&T #2 T&T #2 - T&T decay rate constant = -0.104 - Increased decay rate due to first flush first flush

26. Questions?