ANNUAL MAINTENANCE ESTIMATE...

[20.52.1]providing and placing in horizontal layers filtering media screened washed and cleaned as described below - 1. Top Layer: Fine sand screened, cleaned and washed and graded (effective size 0.2 to 0.4 mm with uniformity coefficient 2.0 to 3.0) from Ghaggar or other approved source

[20.52.2]providing and placing in horizontal layers filtering media screened washed and cleaned as described below - 2. Second layer Coursed sand screened, cleaned and washed and graded from 3 mm to 6 mm (from Ghaggar or approved equivalent quarry)

[20.52.3]providing and placing in horizontal layers filtering media screened washed and cleaned as described below - 3. Third layer Bajri (coursed) screened and washed graded from 20 mm to 25 mm (from Ghaggar or approved equivalent quarry)

[20.52.4]providing and placing in horizontal layers filtering media screened washed and cleaned as described below - 4. Fourth layer Bajri (coursed) screened and washed graded from 20 mm to 25 mm (from Ghaggar or approved equivalent quarry)

[20.52.5]providing and placing in horizontal layers filtering media screened washed and cleaned as described below - 5. Bottom layer Broken stone, screened, washed and graded from 50 mm to 75 mm (from Ghaggar or approved equivalent quarry)