Table 1 Description of wetland cells at WDPl

0

Settling pond

Area = 7000 ft² (1 foot = 0.3048 m), volume = 40 000 ft³

10 days and 20 gpm^b

1

Anaerobic wetlands

Horizontal subsurface flow volume = 30 000 ft³, depth = 2.5 ft 100% river gravel + limestone fragments

9.4 days and 5 gpm

2

Anaerobic wetlands

Horizontal subsurface flow volume = 20 000 ft³, depth = 4 f t 80% river gravel + limestone, 20% compost

6.2 days and 5 gpm

3

Anaerobic wetlands

Upwards subsurface flow volume = 12 000 ft³, depth = 6 f t 50% river gravel + limestone. 50% compost

3.7 days and 5 gpm

4

Anaerobic wetlands

Horizontal subsurface flow volume = 15 000 ft, depth = 2.5 ft 100% river gravel + limestone fragments

4.8 days and 5 gpm

6

Aerobic wetlands

Shallow ponds and riffles area ca. 2000 ft²

Ca. 2 days and 10 gpm

7

Aerobic wetlands

As for cell 6, area ca. 6500 ft²

Ca. 6 days and 10 gpm