On the morning of July 23,
2010, ten turbidity samples were collected in the sediment basin. The
turbidity readings were all well below the performance standard of 250 NTUs,
with the highest result being 30.7 NTUs. Therefore, the skimmer was
flipped to allow discharge from the sedimentation basin. A turbidity
reading was collected at the discharge point shortly after discharge; the
result was 161 NTUs. A turbidity reading collected 10 minutes later
was 92.1 NTUs. The basin was checked approximately every hour
throughout the day with all readings being below 65 NTUs until about 2 pm
when the turbidity readings began to
increase (97.6 NTUs at 2 pm and 181 NTUs at 3 pm). Due to the increase
in turbidity in a short period of time, the skimmer was flipped to stop
discharge from the sedimentation basin.
Additional flocculants (Floc
Logs) were then added to the check dams and in the basin to assist with
settling out the sediments from the basin. There was no additional
discharge from the basin on July 23, 2010.
