Table 7.
Factors coded as dummy variables
| Pattern | Run | Pulp Density | Surface Area | Ferric Chloride | Carbon Dioxide | Air | 9 K medium | Strain | Results As mg/l |
| ----+++ | 1 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | R1 |
| --++--+ | 2 | 0 | 0 | 1 | 1 | 0 | 0 | 1 | R2 |
| -+-+-+- | 3 | 0 | 1 | 0 | 1 | 0 | 1 | 0 | R3 |
| -++-+-- | 4 | 0 | 1 | 1 | 0 | 1 | 0 | 0 | R4 |
| +--++-- | 5 | 1 | 0 | 0 | 1 | 1 | 0 | 0 | R5 |
| +-+--+- | 6 | 1 | 0 | 1 | 0 | 0 | 1 | 0 | R6 |
| ++----+ | 7 | 1 | 1 | 0 | 0 | 0 | 0 | 1 | R7 |
| +++++++ | 8 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | R8 |
Results of As in leachate (mg/l) were determined each 48 hours, to finally have the results of this table 15 times during the 28 days of the experiment