1. TAG Proposal “Forest vegetation as an indicator of natural gas leaks” Don Davis (PI) Lynda Farrell, Consultant

2. GAS WELL DRILLING: POTENTIAL ADVERSE FOREST EFFECTS Gas Wells 60% Forested

3. GAS WELL DRILLING: POTENTIAL ADVERSE FOREST EFFECTS 1. Pad Site Logging & Construction Removal and Sale of Trees

4. Logging Wounds on Residual Trees at Edge 1. Direct Effects 2. Secondary Effects

5. 2. Excavating & Grading 1.“Edge Effects” 2.Surface Water Flow Changes

6. “ Edge Effects ” (Tree Mortality Along Edge) 1.Mortality not necc from salt, etc. 2.May continue for years

7. 3. Leaks & Spills of Brine (+ Frac’n Chemicals?)

8. Leaks from Lined Pits Deer Attracted to Salt

9. Salt Damage

10. 4. Precursors to Ozone Formation (i.e., NO x Emissions from Compressor Stations) Tons/Yr Source: PA DEP (2010) Tons/Yr

11. Ozone-Sensitive Plants Black Cherry Chinese Tallowtree

12. Vegetation Associated with Pipelines Clearing Excavation

13. Grading Seeding Establishment of Grasses, clover, etc.

14. Common Perennial Plants on PA Pipeline Corridors Grass Clover Vetch Trefoil Grass

15. So, what happens if there is a leak in a natural gas pipeline? Root Death Soil atmosphere Soil oxygen depleted Methanobacter (+ Size of leak, Pressure, etc. etc.) Gas migrates upward in an inverted cone **OLD** Pipelines

16. Aerial View Pattern Influenced By Soil Texture Soil Disturbance Within Trench Soil Moisture Depth of Freezing Underground Leak **OLD** Pipelines

17. Woody Shrubs Over Old Pipelines

18. SUMMARY: Early Detection of Leaks Using Dead, Dying, or Discolored Vegetation Above Leaking Natural Gas Pipeline

19. TAG Proposal “Forest vegetation as an indicator of natural gas leaks” 1. Outreach Activities Presentations at meetings Prep of publications, brochures, etc. 2. Aerial surveys above old pipelines to locate patterns of discolored or injured vegetation Follow-up with ground-truth surveys 1. Outreach Activities Presentations at meetings Prep of publications, brochures, etc. 2. Aerial surveys above old pipelines to locate patterns of discolored or injured vegetation Follow-up with ground-truth surveys