### 4.1.1.4 April

Figure 4-4: Scatter Plot of Observed Sulfate fr om the STN network versus the Modeled Sulfate for

the 12km domain (blue x’s) and the 36km domain ( red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites collectively (to p right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117- 0007) (bottom left), and the Ashland STN site (21- 019-0017) (bottom right) for the month of April.

### 4.1.1.5 May

Figure 4-5: Scatter Plot of Observed Sulfate fr om the STN network versus the Modeled Sulfate for

the 12km domain (blue x’s) and the 36km domain ( red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites collectively (to p right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-

0007) (bottom left), and the Ashland STN site (21- 019-0017) (bottom right) for the month of May.

### 4.1.1.6 June

Figure 4-6: Scatter Plot of Observed Sulfate fr om the STN network versus the Modeled Sulfate for

the 12km domain (blue x’s) and the 36km domain ( red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites collectively (to p right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117- 0007) (bottom left), and the Ashland STN site (21- 019-0017) (bottom right) for the month of June.

### 4.1.1.7 July

Figure 4-7: Scatter Plot of Observed Sulfate fr om the STN network versus the Modeled Sulfate for

the 12km domain (blue x’s) and the 36km domain ( red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites collectively (to p right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-

0007) (bottom left), and the Ashland STN site (21- 019-0017) (bottom right) for the month of July.

### 4.1.1.8 August

Figure 4-8: Scatter Plot of Observed Sulfate fr om the STN network versus the Modeled Sulfate for

the 12km domain (blue x’s) and the 36km domain ( red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites collectively (to p right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117- 0007) (bottom left), and the Ashland STN site (21- 019-0017) (bottom right) for the month of August.

### 4.1.1.9 September

Figure 4-9: Scatter Plot of Observed Sulfate fr om the STN network versus the Modeled Sulfate for

the 12km domain (blue x’s) and the 36km domain ( red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites collectively (to p right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117- 0007) (bottom left), and the Ashland STN site ( 21-019-0017) (bottom right) for the month of September.

### 4.1.1.10 October

Figure 4-10: Scatter Plot of Observed Sulfate from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km do main (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of October.

### 4.1.1.11 November

Figure 4-11: Scatter Plot of Observed Sulfate from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km do main (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of November.

### 4.1.1.12 December

Figure 4-12: Scatter Plot of Observed Sulfate from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km do main (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of December.

### 4.1.2 Nitrates

4.1.2.1 January

Figure 4-13: Scatter Plot of Observed Nitrates from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km do main (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Covington STN site (21-117-0007) (middle right), and the Ashland STN site (21-019-0017) (bottom left) for the month of January.

### 4.1.2.2 February

Figure 4-14: Scatter Plot of Observed Nitrates from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km do main (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of February.

### 4.1.2.3 March

Figure 4-15: Scatter Plot of Observed Nitrates from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km do main (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of March.

### 4.1.2.4 April

Figure 4-16: Scatter Plot of Observed Nitrates from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km do main (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of April.

### 4.1.2.5 May

Figure 4-17: Scatter Plot of Observed Nitrates from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km do main (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of May.

### 4.1.2.6 June

Figure 4-18: Scatter Plot of Observed Nitrates from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km do main (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of June.

### 4.1.2.7 July

Figure 4-19: Scatter Plot of Observed Nitrates from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km do main (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of July.

### 4.1.2.8 August

Figure 4-20: Scatter Plot of Observed Nitrates from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km do main (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of August.

### 4.1.2.9 September

Figure 4-21: Scatter Plot of Observed Nitrates from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km do main (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of September.

### 4.1.2.10 October

Figure 4-22: Scatter Plot of Observed Nitrates from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km do main (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of October.

### 4.1.2.11 November

Figure 4-23: Scatter Plot of Observed Nitrates from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km do main (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of November.

### 4.1.2.12 December

Figure 4-24: Scatter Plot of Observed Nitrates from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km do main (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of December.

### 4.1.3 Ammonium

4.1.3.1 January

Figure 4-25: Scatter Plot of Observed Ammoni um from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Covington STN site (21-117-0007) (middle right), and the Ashland STN site (21-019-0017) (bottom left) for the month of January.

### 4.1.3.2 February

Figure 4-26: Scatter Plot of Observed Ammoni um from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of February.

### 4.1.3.3 March

Figure 4-27: Scatter Plot of Observed Ammoni um from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of March.

### 4.1.3.4 April

Figure 4-28: Scatter Plot of Observed Ammoni um from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of April.

### 4.1.3.5 May

Figure 4-29: Scatter Plot of Observed Ammoni um from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of May.

### 4.1.3.6 June

Figure 4-30: Scatter Plot of Observed Ammoni um from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of June.

### 4.1.3.7 July

Figure 4-31: Scatter Plot of Observed Ammoni um from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of July.

### 4.1.3.8 August

Figure 4-32: Scatter Plot of Observed Ammoni um from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of August.

### 4.1.3.9 September

Figure 4-33: Scatter Plot of Observed Ammoni um from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of September.

### 4.1.3.10 October

Figure 4-34: Scatter Plot of Observed Ammoni um from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of October.

### 4.1.3.11 November

Figure 4-35: Scatter Plot of Observed Ammoni um from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of November.

### 4.1.3.12 December

Figure 4-36: Scatter Plot of Observed Ammoni um from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of December.

### 4.1.4 Organic Carbon

4.1.4.1 January

Figure 4-37: Scatter Plot of Observed Organic Carbon from the STN network versus the Modeled

Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Covington STN site (21-11-0007) (middle right), and the Ashland STN site (21-019-0017) (bottom left) for the month of January.

### 4.1.4.2 February

Figure 4-38: Scatter Plot of Observed Organic Carbon from the STN network versus the Modeled

Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of February.

### 4.1.4.3 March

Figure 4-39: Scatter Plot of Observed Organic Carbon from the STN network versus the Modeled

Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of March.

### 4.1.4.4 April

Figure 4-40: Scatter Plot of Observed Organic Carbon from the STN network versus the Modeled

Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of April.

### 4.1.4.5 May

Figure 4-41: Scatter Plot of Observed Organic Carbon from the STN network versus the Modeled

Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of May.

### 4.1.4.6 June

Figure 4-42: Scatter Plot of Observed Organic Carbon from the STN network versus the Modeled

Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of June.

### 4.1.4.7 July

Figure 4-43: Scatter Plot of Observed Organic Carbon from the STN network versus the Modeled

Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of July.

### 4.1.4.8 August

Figure 4-44: Scatter Plot of Observed Organic Carbon from the STN network versus the Modeled

Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of August.

### 4.1.4.9 September

Figure 4-44: Scatter Plot of Observed Organic Carbon from the STN network versus the Modeled

Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of September.

### 4.1.4.10 October

Figure 4-44: Scatter Plot of Observed Organic Carbon from the STN network versus the Modeled

Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of October.

### 4.1.4.11 November

Figure 4-47: Scatter Plot of Observed Organic Carbon from the STN network versus the Modeled

Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of November.

### 4.1.4.12 December

Figure 4-48: Scatter Plot of Observed Organic Carbon from the STN network versus the Modeled

Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of December.

### 4.1.5 Elemental Carbon

4.1.5.1 January

Figure 4-49: Scatter Plot of Observed Elemen tal Carbon from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky ST N sites collectively (top right), the APCD Barrett STN site (21-111-0048)(middle left), the Covington STN site (21-117-0007) (middle right), and the Ashland STN site (21-019-0017) (bottom left) for the month of January.

### 4.1.5.2 February

Figure 4-50: Scatter Plot of Observed Elemen tal Carbon from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky ST N sites collectively (top right), the APCD Barrett

STN site (21-111-0048) (middle left), the Southw ick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashland STN site (21-019-0017) (bottom right) for the month of February.

### 4.1.5.3 March

Figure 4-51: Scatter Plot of Observed Elemen tal Carbon from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky ST N sites collectively (top right), the APCD Barrett

STN site (21-111-0048) (middle left), the Southw ick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashland STN site (21-019-0017) (bottom right) for the month of March.

### 4.1.5.4 April

Figure 4-52: Scatter Plot of Observed Elemen tal Carbon from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky ST N sites collectively (top right), the APCD Barrett

STN site (21-111-0048) (middle left), the Southw ick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashland STN site (21-019-0017) (bottom right) for the month of April.

### 4.1.5.5 May

Figure 4-53: Scatter Plot of Observed Elemen tal Carbon from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky ST N sites collectively (top right), the APCD Barrett

STN site (21-111-0048) (middle left), the Southw ick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashland STN site (21-019-0017) (bottom right) for the month of May.

### 4.1.5.6 June

Figure 4-54: Scatter Plot of Observed Elemen tal Carbon from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky ST N sites collectively (top right), the APCD Barrett

STN site (21-111-0048) (middle left), the Southw ick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashland STN site (21-019-0017) (bottom right) for the month of June.

### 4.1.5.7 July

Figure 4-55: Scatter Plot of Observed Elemen tal Carbon from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky ST N sites collectively (top right), the APCD Barrett

STN site (21-111-0048) (middle left), the Southw ick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashland STN site (21-019-0017) (bottom right) for the month of July.

### 4.1.5.8 August

Figure 4-56: Scatter Plot of Observed Elemen tal Carbon from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky ST N sites collectively (top right), the APCD Barrett

STN site (21-111-0048) (middle left), the Southw ick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashland STN site (21-019-0017) (bottom right) for the month of August.

### 4.1.5.9 September

Figure 4-57: Scatter Plot of Observed Elemen tal Carbon from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky ST N sites collectively (top right), the APCD Barrett

STN site (21-111-0048) (middle left), the Southw ick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashland STN site (21-019-0017) (bottom right) for the month of September.

### 4.1.5.10 October

Figure 4-58: Scatter Plot of Observed Elemen tal Carbon from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky ST N sites collectively (top right), the APCD Barrett

STN site (21-111-0048) (middle left), the Southw ick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashland STN site (21-019-0017) (bottom right) for the month of October.

### 4.1.5.11 November

Figure 4-59: Scatter Plot of Observed Elemen tal Carbon from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky ST N sites collectively (top right), the APCD Barrett

STN site (21-111-0048) (middle left), the Southw ick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashland STN site (21-019-0017) (bottom right) for the month of November.

### 4.1.5.12 December

Figure 4-60: Scatter Plot of Observed Elemen tal Carbon from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky ST N sites collectively (top right), the APCD Barrett STN site (21-111-0048)(middle left), and the Sout hwick STN site (21-111-0043) (middle right) for

the month of December.

### 4.1.6 Total PM 2.5



### 4.1.6.1 January

Figure 4-61: Scatter Plot of Reconstructed PM 2.5 from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of January.

### 4.1.6.2 February

Figure 4-62: Scatter Plot of Reconstructed PM 2.5 from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of February.

### 4.1.6.3 March

Figure 4-63: Scatter Plot of Reconstructed PM 2.5 from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of March.

### 4.1.6.4 April

Figure 4-64: Scatter Plot of Reconstructed PM 2.5 from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of April.

### 4.1.6.5 May

Figure 4-65: Scatter Plot of Reconstructed PM 2.5 from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of May.

### 4.1.6.6 June

Figure 4-66: Scatter Plot of Reconstructed PM 2.5 from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of June.

### 4.1.6.7 July

Figure 4-67: Scatter Plot of Reconstructed PM 2.5 from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of July.

### 4.1.6.8 August

Figure 4-68: Scatter Plot of Reconstructed PM 2.5 from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of August.

### 4.1.6.9 September

Figure 4-69: Scatter Plot of Reconstructed PM 2.5 from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the month of September.

### 4.1.6.10 October

Figure 4-70: Scatter Plot of Reconstructed PM 2.5 from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of October.

### 4.1.6.11 November

Figure 4-71: Scatter Plot of Reconstructed PM 2.5 from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of November.

### 4.1.6.12 December

Figure 4-72: Scatter Plot of Reconstructed PM 2.5 from the STN network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36k m domain (red +’s) for all VISTAS STN sites collectively (top left), all Kentucky STN sites co llectively (top right), the APCD Barrett STN site (21-111-0048) (middle left), the Southwick STN site (21-111-0043) (middle right), the Covington STN site (21-117-0007) (bottom left), and the Ashla nd STN site (21-019-0017) (bottom right) for the

month of December.

### 4.2 FRM Scatter plots

4.2.1 January

Figure 4-73: Scatter Plot of PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km

domain (blue x’s) and the 36km domain (red +’s) for all VISTAS FRM sites collectively (top), all Kentucky FRM sites collectively (bo ttom) for the month of January.Figure 4-74: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for the Bullitt FRM site (21-029- 0006)(top left), the Barret FRM site (21-111-0048) (top right), the Beecher FRM site (21-111-

0044)(bottom left), and the Watson FRM site (21-111-0051)(bottom right) for the month of January.Figure 4-75: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for the 37 th & Southern FRM site (21- 111-0043)(top left), the Campbell FR M site (21-037-0003)(top right), the Kenton FRM site (21-117- 0007)(bottom left), and the Boyd FRM site (21-01 9-0017)(bottom right) for the month of January.

### 4.2.2 February

Figure 4-76: Scatter Plot of PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km

domain (blue x’s) and the 36km domain (red +’s) for all VISTAS FRM sites collectively (top), all Kentucky FRM sites collectively (bo ttom) for the month of February.Figure 4-77: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for the Bullitt FRM site (21-029- 0006)(top left), the Barret FRM site (21-111-0048) (top right), the Beecher FRM site (21-111-

0044)(bottom left), and the Watson FRM site (21-111-0051)(bottom right) for the month of February.Figure 4-78: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for the 37 th & Southern FRM site (21- 111-0043)(top left), the Campbell FR M site (21-037-0003)(top right), the Kenton FRM site (21-117- 0007)(bottom left), and the Boyd FRM site (21-019- 0017)(bottom right) for the month of February.

### 4.2.3 March

Figure 4-79: Scatter Plot of PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km

domain (blue x’s) and the 36km domain (red +’s) for all VISTAS FRM sites collectively (top), all Kentucky FRM sites collectively (bottom) for the month of March.Figure 4-80: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for the Bullitt FRM site (21-029- 0006)(top left), the Barret FRM site (21-111-0048) (top right), the Beecher FRM site (21-111- 0044)(bottom left), and the Watson FRM site (21- 111-0051)(bottom right) for the month of March.Figure 4-81: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for the 37 th & Southern FRM site (21- 111-0043)(top left), the Campbell FR M site (21-037-0003)(top right), the Kenton FRM site (21-117-

0007)(bottom left), and the Boyd FRM site (21-019-0017)(bottom right) for the month of March.

### 4.2.4 April

Figure 4-82: Scatter Plot of PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km

domain (blue x’s) and the 36km domain (red +’s) for all VISTAS FRM sites collectively (top), all Kentucky FRM sites collectively (bottom) for the month of April.Figure 4-83: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for the Bullitt FRM site (21-029- 0006)(top left), the Barret FRM site (21-111-0048) (top right), the Beecher FRM site (21-111- 0044)(bottom left), and the Watson FRM site (21- 111-0051)(bottom right) for the month of April.Figure 4-84: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for the 37 th & Southern FRM site (21- 111-0043)(top left), the Campbell FR M site (21-037-0003)(top right), the Kenton FRM site (21-117-

0007)(bottom left), and the Boyd FRM site (21-019-0017)(bottom right) for the month of April.

### 4.2.5 May

Figure 4-85: Scatter Plot of PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km

domain (blue x’s) and the 36km domain (red +’s) for all VISTAS FRM sites collectively (top), all Kentucky FRM sites collectively (bottom) for the month of May.Figure 4-86: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for the Bullitt FRM site (21-029- 0006)(top left), the Barret FRM site (21-111-0048) (top right), the Beecher FRM site (21-111- 0044)(bottom left), and the Watson FRM site (21-111-0051)(bottom right) for the month of May.Figure 4-87: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for the 37 th & Southern FRM site (21- 111-0043)(top left), the Campbell FR M site (21-037-0003)(top right), the Kenton FRM site (21-117- 0007)(bottom left), and the Boyd FRM site (21-019-0017)(bottom right) for the month of May.

### 4.2.6 June

Figure 4-88: Scatter Plot of PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km

domain (blue x’s) and the 36km domain (red +’s) for all VISTAS FRM sites collectively (top), all Kentucky FRM sites collectively (bottom) for the month of June.Figure 4-89: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for the Bullitt FRM site (21-029- 0006)(top left), the Barret FRM site (21-111-0048) (top right), the Beecher FRM site (21-111- 0044)(bottom left), and the Watson FRM site (21- 111-0051)(bottom right) for the month of June.Figure 4-90: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for the 37 th & Southern FRM site (21- 111-0043)(top left), the Campbell FR M site (21-037-0003)(top right), the Kenton FRM site (21-117- 0007)(bottom left), and the Boyd FRM site (21-01 9-0017)(bottom right) for the month of June.

### 4.2.7 July

Figure 4-91: Scatter Plot of PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km

domain (blue x’s) and the 36km domain (red +’s) for all VISTAS FRM sites collectively (top), all Kentucky FRM sites collectively (b ottom) for the month of July.Figure 4-92: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for the Bullitt FRM site (21-029- 0006)(top left), the Barret FRM site (21-111-0048) (top right), the Beecher FRM site (21-111- 0044)(bottom left), and the Watson FRM site (21- 111-0051)(bottom right) for the month of July.Figure 4-93: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for the 37 th & Southern FRM site (21- 111-0043)(top left), the Campbell FR M site (21-037-0003)(top right), the Kenton FRM site (21-117- 0007)(bottom left), and the Boyd FRM site (21-019-0017)(bottom right) for the month of July.

### 4.2.8 August

Figure 4-94: Scatter Plot of PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km

domain (blue x’s) and the 36km domain (red +’s) for all VISTAS FRM sites collectively (top), all Kentucky FRM sites collectively (bottom) for the month of August.Figure 4-95: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for the Bullitt FRM site (21-029- 0006)(top left), the Barret FRM site (21-111-0048) (top right), the Beecher FRM site (21-111- 0044)(bottom left), and the Watson FRM site (21- 111-0051)(bottom right) for the month of August.Figure 4-96: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for the 37 th & Southern FRM site (21- 111-0043)(top left), the Campbell FR M site (21-037-0003)(top right), the Kenton FRM site (21-117-

0007)(bottom left), and the Boyd FRM site (21-019-0017)(bottom right) for the month of August.

### 4.2.9 September

Figure 4-97: Scatter Plot of PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km

domain (blue x’s) and the 36km domain (red +’s) for all VISTAS FRM sites collectively (top), all Kentucky FRM sites collectively (bottom) for the month of September.Figure 4-98: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for the Bullitt FRM site (21-029- 0006)(top left), the Barret FRM site (21-111-0048) (top right), the Beecher FRM site (21-111-

0044)(bottom left), and the Watson FRM site (21-111-0051)(bottom right) for the month of September.Figure 4-99: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for the 37 th & Southern FRM site (21- 111-0043)(top left), the Campbell FR M site (21-037-0003)(top right), the Kenton FRM site (21-117- 0007)(bottom left), and the Boyd FRM site (21-019-0017)(bottom right) for the month of September.

### 4.2.10 October

Figure 4-100: Scatter Plot of PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for all VISTAS FRM sites collectively (top), all Kentucky FRM sites collectively (b ottom) for the month of October.Figure 4-101: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km doma in (red +’s) for the Bullitt FRM site (21-029-

0006)(top left), the Barret FRM site (21-111-0048) (top right), the Beecher FRM site (21-111- 0044)(bottom left), and the Watson FRM site (21-111- 0051)(bottom right) for the month of October.Figure 4-102: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and th e 36km domain (red +’s) for the 37 th & Southern FRM site (21-111-0043)(top left), the Campbe ll FRM site (21-037-0003)(top right), the Kenton FRM site (21- 117-0007)(bottom left), and the Boyd FRM site (21-019-0017)(bottom right) for the month of

October.

### 4.2.11 November

Figure 4-103: Scatter Plot of PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for all VISTAS FRM sites collectively (top), all Kentucky FRM sites collectively (bottom) for the month of November.Figure 4-104: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km doma in (red +’s) for the Bullitt FRM site (21-029-

0006)(top left), the Barret FRM site (21-111-0048) (top right), the Beecher FRM site (21-111-

0044)(bottom left), and the Watson FRM site (21-111-0051)(bottom right) for the month of

November.Figure 4-105: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and th e 36km domain (red +’s) for the 37 th & Southern FRM site (21-111-0043)(top left), the Campbe ll FRM site (21-037-0003)(top right), the Kenton FRM site (21- 117-0007)(bottom left), and the Boyd FRM site (21-019-0017)(bottom right) for the month of

November.

### 4.2.12 December

Figure 4-106: Scatter Plot of PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km domain (red +’s) for all VISTAS FRM sites collectively (top), all Kentucky FRM sites collectively (bottom) for the month of December.Figure 4-107: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and the 36km doma in (red +’s) for the Bullitt FRM site (21-029-

0006)(top left), the Barret FRM site (21-111-0048) (top right), the Beecher FRM site (21-111-

0044)(bottom left), and the Watson FRM site (21-111-0051)(bottom right) for the month of

December.Figure 4-108: Scatter Plot of Observed PM 2.5 from the FRM network versus the Modeled Sulfate for the 12km domain (blue x’s) and th e 36km domain (red +’s) for the 37 th & Southern FRM site (21-111-0043)(top left), the Campbe ll FRM site (21-037-0003)(top right), the Kenton FRM site (21- 117-0007)(bottom left), and the Boyd FRM site (21-019-0017)(bottom right) for the month of

December.

## 5. Time Series

The time series plots that disp lay model predicted particulate matter component concentrations for the 12km grid resolution (pur ple line), the 36 km grid resolu tion (blue line), and observed concentrations (red line) are presented in this se ction. Observations ar e reported per the polling frequency of the site presented, and have been paired with their corr esponding model predicted value. Time series for five of component sp ecies of particulate matter (sulfates, nitrates, ammonium, organic carbon, and elemental carbon) are presented by species, for the APCD/Barret, Southwick, Covington, and Ashla nd STN monitoring sites, for each month of the year in Section 5.1.

Time series for the total reconstructed fine particulate mass for the STN monitors follows the species plots in Section 5.1.6.

Additionally, the total observed PM 2.5 

### mass form FRM sites are plotted with the 12km and 36 km grid resolution modeled values in Section 5.2. The annual fr actional bias and fractional error

for the site for both 12km and 36k m grid resolution is presented in top right corner of all the graphs for reference.

Overall, the model captures the cycle of polluta nt build-up and clean-out very well across the major constituents of PM 2.5 

### . Nitrates performance is the weakest, but the general pattern of

increase and decreases is still reasonably captured, with most of the poor performance occurring in the later half of the year. The ammonium cy cle is actually captured quite well, especially in the April to May timeframe. Th e general good performance of the components translates to good performance in the total reconstructed PM 2.5 

### mass from the STN sites. The FRM data also shows the model responds appropri ately to shift in weather pattern s and pollutant patterns, as the FRM modeled response mirrors the observed response quite well.

The negative bias in the model is still apparent in the times seri es; however, the plots show that the model is doing a good job of capturing th e pattern of increases and decreases in PM 2.5 

### and it’s constituents. This is encouraging becau se it shows the model chemistry is reacting appropriately to meteorology and is performing well.

### 5.1 STN Time Series

5.1.1 Sulfates

5.1.1.1 January

Figure 5-1: January 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).



### NOTE: DATA FOR THE SOUTHWICK STN MONITOR (21- 111-0043) IS NOT

AVAILABLE FOR THIS MONTHFigure 5-2: January 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-3: January 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate

Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.1.2 February

Figure 5-4: February 2002Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-5: February 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-6: February 2002Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-7: February 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate

Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.1.3 March

Figure 5-8: March 2002Time Series of Observed Sul fate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-9: March 2002 Time Series of Observed Sul fate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-10: March 2002Time Series of Observed Sul fate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-11: March 2002 Time Series of Observed Sul fate levels (red line) and Modeled Sulfate

Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.1.4 April

Figure 5-12: April 2002Time Series of Observed Sul fate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-13: April 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-14: April 2002Time Series of Observed Sul fate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-15: April 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.1.5 May

Figure 5-16: May 2002Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-17: May 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels

at both 36km (blue line) and 12km (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-18: May 2002Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-19: May 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the Ashland STN monitor (21- 019-0017).

### 5.1.1.6 June

Figure 5-20: June 2002Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-21: June 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-22: June 2002Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-23: June 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.1.7 July

Figure 5-24: July 2002Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-25: July 2002 Time Series of Observed Sulfa te levels (red line) and Modeled Sulfate Levels

at both 36km (blue line) and 12km (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-26: July 2002Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-27: July 2002 Time Series of Observed Sulfa te levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the Ashland STN monitor (21- 019-0017).

### 5.1.1.8 August

Figure 5-28: August 2002Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-29: August 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-30: August 2002Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-31: August 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate

Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.1.9 September

Figure 5-32: September 2002Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-33: September 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate

Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-34: September 2002Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-35: September 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.1.10 October

Figure 5-36: October 2002Time Series of Observed Sul fate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-37: October 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-38: October 2002Time Series of Observed Sul fate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-39: October 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate

Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.1.11 November

Figure 5-40: November 2002Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-41: November 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate

Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-42: November 2002Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-43: November 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.1.12 December

Figure 5-44: December 2002Time Series of Observed Sul fate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-45: December 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate

Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-46: December 2002Time Series of Observed Sul fate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-47: December 2002 Time Series of Observed Sulfate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.2 Nitrates

5.1.2.1 January

Figure 5-48: January 2002Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

NOTE: DATA FOR THE SO UTHWICK STN MONITOR (21- 111-0043) IS NOT AVAILABLE

FOR THIS MONTHFigure 5-49: January 2002Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-50: January 2002 Time Series of Observed Nitrate levels (red line) and Modeled Sulfate

Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.2.2 February

Figure 5-51: February 2002Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-52: February 2002 Time Series of Observed Nitrate levels (red line) and Modeled Sulfate

Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-53: February 2002Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-54: February 2002 Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.2.3 March

Figure 5-55: March 2002Time Series of Observed Ni trate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-56: March 2002 Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-57: March 2002Time Series of Observed Ni trate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-58: March 2002 Time Series of Observed Nitrate levels (red line) and Modeled Sulfate

Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.2.4 April

Figure 5-59: April 2002Time Series of Observed Ni trate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-60: April 2002 Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-61: April 2002Time Series of Observed Ni trate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-62: April 2002 Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.2.5 May

Figure 5-63: May 2002Time Series of Observed Nitrat e levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-64: May 2002 Time Series of Observed Nitrat e levels (red line) and Modeled Sulfate Levels

at both 36km (blue line) and 12km (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-65: May 2002Time Series of Observed Nitrat e levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-66: May 2002 Time Series of Observed Nitrat e levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the Ashland STN monitor (21- 019-0017).

### 5.1.2.6 June

Figure 5-67: June 2002Time Series of Observed Nitrat e levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-68: June 2002 Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-69: June 2002Time Series of Observed Nitrat e levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-70: June 2002 Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.2.7 July

Figure 5-71: July 2002Time Series of Observed Nitrat e levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-72: July 2002 Time Series of Observed Nitr ate levels (red line) and Modeled Sulfate Levels

at both 36km (blue line) and 12km (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-73: July 2002Time Series of Observed Nitrat e levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-74: July 2002 Time Series of Observed Nitr ate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the Ashland STN monitor (21- 019-0017).

### 5.1.2.8 August

Figure 5-75: August 2002Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-76: August 2002 Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-77: August 2002Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-78: August 2002 Time Series of Observed Nitrate levels (red line) and Modeled Sulfate

Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.2.9 September

Figure 5-79: September 2002Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-80: September 2002 Time Series of Observed Nitrate levels (red line) and Modeled Sulfate

Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-81: September 2002Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-82: September 2002 Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.2.10 October

Figure 5-83: October 2002Time Series of Observed Ni trate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-84: October 2002 Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-85: October 2002Time Series of Observed Ni trate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-86: October 2002 Time Series of Observed Nitrate levels (red line) and Modeled Sulfate

Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.2.11 November

Figure 5-87: November 2002Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-88: November 2002 Time Series of Observed Nitrate levels (red line) and Modeled Sulfate

Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-89: November 2002Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-90: November 2002 Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.2.12 December

Figure 5-91: December 2002Time Series of Observed Ni trate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-92: December 2002 Time Series of Observed Nitrate levels (red line) and Modeled Sulfate

Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-93: December 2002Time Series of Observed Ni trate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-94: December 2002 Time Series of Observed Nitrate levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.3 NH4

5.1.3.1 January

Figure 5-95: January 2002Time Series of Observed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) a nd 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).



### NOTE: 

### DATA FOR THE SOUTHWICK STN MONITOR (21-111-0043) IS NOT

AVAILABLE FOR THIS MONTHFigure 5-96: January 2002Time Series of Observed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-97: January 2002 Time Series of Observ ed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.3.2 February

Figure 5-98: February 2002Time Series of Observ ed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) a nd 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-99: February 2002 Time Series of Observ ed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-100: February 2002Time Series of Observed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-101: February 2002 Time Series of Observ ed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.3.3 March

Figure 5-102: March 2002Time Series of Observed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) a nd 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-103: March 2002 Time Series of Observed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-104: March 2002Time Series of Observed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-105: March 2002 Time Series of Observed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.3.4 April

Figure 5-106: April 2002Time Series of Observed Ammo nium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-107: April 2002 Time Series of Observed Ammo nium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-108: April 2002Time Series of Observed Ammo nium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-109: April 2002 Time Series of Observed Ammo nium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.3.5 May

Figure 5-110: May 2002Time Series of Observed Ammo nium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-111: May 2002 Time Series of Observed Ammo nium levels (red line) and Modeled Sulfate

Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-112: May 2002Time Series of Observed Ammo nium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-113: May 2002 Time Series of Observed Ammo nium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.3.6 June

Figure 5-114: June 2002Time Series of Observed Ammo nium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-115: June 2002 Time Series of Observed Am monium levels (red line) and Modeled Sulfate

Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-116: June 2002Time Series of Observed Ammo nium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-117: June 2002 Time Series of Observed Am monium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.3.7 July

Figure 5-118: July 2002Time Series of Observed Ammo nium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-119: July 2002 Time Series of Observed Am monium levels (red line) and Modeled Sulfate

Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-120: July 2002Time Series of Observed Ammo nium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-121: July 2002 Time Series of Observed Am monium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (pur ple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.3.8 August

Figure 5-122: August 2002Time Series of Observed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) a nd 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-123: August 2002 Time Series of Observ ed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-124: August 2002Time Series of Observed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-125: August 2002 Time Series of Observ ed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.3.9 September

Figure 5-126: September 2002Time Series of Observed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) a nd 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-127: September 2002 Time Series of Observed Ammonium le vels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-128: September 2002Time Series of Observed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-129: September 2002 Time Series of Observed Ammonium le vels (red line) and Modeled

Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.3.10 October

Figure 5-130: October 2002Time Series of Observed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) a nd 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-131: October 2002 Time Series of Observed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-132: October 2002Time Series of Observed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-133: October 2002 Time Series of Observed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.3.11 November

Figure 5-134: November 2002Time Series of Observed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) a nd 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-135: November 2002 Time Series of Observ ed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-136: November 2002Time Series of Observed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-137: November 2002 Time Series of Observ ed Ammonium levels (red line) and Modeled

Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.3.12 December

Figure 5-138: December 2002Time Series of Observed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) a nd 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-139: December 2002 Time Series of Observ ed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-140: December 2002Time Series of Observed Ammonium levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-141: December 2002 Time Series of Observ ed Ammonium levels (red line) and Modeled

Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.4 Organic Carbon

5.1.4.1 January

Figure 5-142: January 2002Time Series of Observed Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) a nd 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).



### NOTE: DATA FOR THE SOUTHWICK STN MONITOR (21- 111-0043) IS NOT

AVAILABLE FOR THIS MONTHFigure 5-143: January 2002Time Series of Observed Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-144: January 2002 Time Series of Observed Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.4.2 February

Figure 5-145: February 2002Time Series of Observed Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-146: February 2002 Time Series of Observed Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-147: February 2002Time Series of Observed Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-148: February 2002 Time Series of Observed Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.4.3 March

Figure 5-149: March 2002Time Series of Observed Or ganic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) a nd 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-150: March 2002 Time Series of Observed Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-151: March 2002Time Series of Observed Or ganic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-152: March 2002 Time Series of Observed Organic Carbon levels (red line) and Modeled

Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.4.4 April

Figure 5-153: April 2002Time Series of Observed Or ganic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) a nd 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-154: April 2002 Time Series of Observed Or ganic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-155: April 2002Time Series of Observed Or ganic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-156: April 2002 Time Series of Observed Or ganic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.4.5 May

Figure 5-157: May 2002Time Series of Observed Organ ic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) a nd 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-158: May 2002 Time Series of Observed Or ganic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-159: May 2002Time Series of Observed Organ ic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-160: May 2002 Time Series of Observed Or ganic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.4.6 June

Figure 5-161: June 2002Time Series of Observed Or ganic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) a nd 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-162: June 2002 Time Series of Observed Or ganic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-163: June 2002Time Series of Observed Or ganic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-164: June 2002 Time Series of Observed Or ganic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.4.7 July

Figure 5-165: July 2002Time Series of Observed Or ganic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) a nd 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-166: July 2002 Time Series of Observed Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-167: July 2002Time Series of Observed Or ganic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-168: July 2002 Time Series of Observed Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.4.8 August

Figure 5-169: August 2002Time Series of Observed Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) a nd 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-170: August 2002 Time Series of Observed Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-171: August 2002Time Series of Observed Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-172: August 2002 Time Series of Observed Organic Carbon levels (red line) and Modeled

Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.4.9 September

Figure 5-173: September 2002Time Series of Observed Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-174: September 2002 Time Series of Obse rved Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-175: September 2002Time Series of Observed Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-176: September 2002 Time Series of Obse rved Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.4.10 October

Figure 5-177: October 2002Time Series of Observed Or ganic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) a nd 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-178: October 2002 Time Series of Observed Organic Carbon levels (red line) and Modeled

Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-179: October 2002Time Series of Observed Or ganic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-180: October 2002 Time Series of Observed Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12k m (purple line) grind resolution for the Ashland STN monitor (21-019-0017).

### 5.1.4.11 November

Figure 5-181: November 2002Time Series of Observed Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the APCD/Barret STN monitor (21-111-0048).

Figure 5-182: November 2002 Time Series of Observ ed Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the Southwick STN monitor (21-111-0043).Figure 5-183: November 2002Time Series of Observed Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the Covington STN monitor (21-117-0007).

Figure 5-184: November 2002 Time Series of Observ ed Organic Carbon levels (red line) and Modeled Sulfate Levels at both 36km (blue line) and 12km (purple line) grind resolution for the Ashland STN monitor (21-019-0017).