Table 2.
Plume Encounters That Exhibited Elevated Levels of at Least One of the Three Reactive Bromine Compounds (Br2, BrNO2, and BrCl) Detected by the HRToF-CIMS
| Plume # | RF # date time (EST) | N2O5:SO2 (ppb:ppb) mean N2O5 at edge (ppt) R(N2O5 vs. SO2) | Bry:SO2 (ppb:ppb) | Distance (km) and time (hr) since emission | Plant(s) | Coal type | SO2 control technology |
|---|---|---|---|---|---|---|---|
| 5 | RF 2 | −1.0 × 10 4 ppb:ppb 10 ppt | 2.1 × 10−4 | 3.8 km 0.3 hr | Gavin | Bituminous, subbituminous | Wet FGD |
| 6 February 17:02 | −0.83 | 6.0 km 0.4 hr | Kyger | Bituminous, subbituminous | Wet FGD | ||
| 9 | RF 2 | 8.0 × 10−4 ppb:ppb 29 ppt | 6.1 × 10−4 | 11.9 km 0.4 hr | Grant | Bituminous waste coal | No FGD Reagent injection |
| 6 February 18:25 | 0.73 | 35.6 km 1.3 hr | Harrison | Bituminous | Wet scrubbers | ||
| 14 | RF 7 | −1.1 × 10−2 ppb:ppb 670 ppt | 1.5 × 10−4 | 11.3 km 0.7 hr | Roxboro | Bituminous, subbituminous | Wet FGD |
| 24 February 6:52 | −0.85 | 22.5 km 1.3 hr | CPI USA Roxboro | Bituminous, biomass | No FGD | ||
| 27.1 km 1.6 hr | Mayo | Bituminous, subbituminous | Wet FGD | ||||
| 16 | RF 9 | −4.0 × 10−4 ppb:ppb 28 ppt | 0.25 × 10−4 | 18.0 km 0.9 hr | Seward | Bituminous waste coal | Dry scrubber (#1 and 2) |
| 3 March 2:42 | −0.34 | 19.1 km 1.0 hr | Conemaugh | Bituminous | Wet FGD | ||
| 35.8 km 1.8 hr | Homer City | Bituminous | Dry FGD (Units 1 and 2) Semidry FGD (Unit 3) | ||||
| 54.7 km 2.8 hr | Armstrong Power, LLC | Natural gas/diesel | No FGD Reagent injection | ||||
| 55.7 km 2.8 hr | Keystone | Bituminous | Wet FGD | ||||
| 21 | RF 9 | 2.0 × 10−4 ppb:ppb 86 ppt | 0.40 × 10−4 | 54.2 km 8.2 hr | Ebensburg | Waste coal (bituminous) | No FGD Reagent injection |
| 3 March 4:29 | 0.10 | 54.4 km 8.3 hr | Cambria | Waste coal (bituminous) | No FGD Reagent injection | ||
| 42 | RF | −7.1 × 10−3 ppb:ppb 618 ppt | 0.38 × 10−4 | 5.2 km 0.32 hr | Harllee Branch | Bituminous | No FGD |
| March 3:35 | −0.51 | ||||||
| 44 | RF 11 | 0 ppb:ppb 2 ppt | 7.0 ×10−4 | 2.7 km 0.15 hr | Homer City Generating Station | Bituminous | Dry FGD (Units 1 and 2) Semi-dry FGD (Unit 3) |
| 9 March 16:00 | −0.18 |
Note. We define Bry as the sum of these three species. The times since emission were calculated assuming that the observed wind speed at the plume intercept location remained constant. HRToF-CIMS = high-resolution time of flight chemical ionization spectrometer; FGD = flue gas desulfurization; EST = Eastern Standard Time.