Trackout within site stabilzed area and onto Latah Street northbound.

Final trackout warning issued. Correction requests:

- sweep up Latah Street
- sweep/rinse (if water can be contained onsite) exisitng asphalt within site
- refresh rock construction entrance
- prohibit employee parking in the dirt or mud, set up parking area on stabilized area

Follow up scheduled for Thursday morning.

Permit posted, trash contained, lined washout pit behind building next to portapot. No trackout or discharges occuring. Approved.

Follow up turbidity testing conducted to determine source of increase in turbidity between Ridgepoint Pond through bypass pipe system to the site outfall.

Testing conducted with brand new Hach 2100Q turbidimeter, full calibration completed 6/8 as well as the older Hach 2100Q used for previous turbidity measurements

Results:
background inflow to Ridgepoint Pond - no flow at time of inspection (dry conditions, no discharges from water line project)

Ridgepoint pond surface water near outlet:
new meter 20.7 NTU; old meter 22.2 NTU

Ridgepoint pond outlet manhole before entering bypass pipe: new meter 57.5, old meter 59.5

Bypass water sample dropping into manhole that has 12" connection from lower pond and the 12" outfall pipe: new meter 50.3 , old meter 57.6. * no significant change from pond outlet manhole.

Water in detention dam with capped outflow pipe:
new meter 383 NTU, old meter 427 NTU

Outfall in pipe : new meter 176 NTU, old meter 198 NTU

Conclusion:

bypass water from Ridgepoint Pond is getting additional flows either from muddy groundwater interflow/inflow in manhole, or the detention pond cap is allow some of the high turbidity water to flow out and join the bypass water. At the final manhole water increased turbidity from 50.3 NTU to 176 NTU. With no official background water flowing into site to compare to, this is still a visibly turbid discharge offsite. Roadway stormwater runoff in this area (when not polluted by another construciton site) has been previously tested to be between 20-50 NTU

Notified site stormwater of finding.

Correction requests:
- fix issue with manhole or detention pond cap
- install sediment control wattle at the perimeter edge of the dirt slopes just above the outfall pipes and outfall rip rap and spread some mulch or seed to stabilize the currently bare ground.