Boyce Hydro, LLC (BHLLC) update on the status of the seepage area at Sanford Dam – Aug. 25, 2010

This is an update from Boyce Hydro:

BHLLC started monitoring the seepage areas, drain tiles and embankment piezometers three times a day since August 14th. The current status of the project is as follows:

1. The pond level is down to 627.6 which is approximately 3.2 feet below normal pool.

2. Last night a trace of rain at Sanford was received.

3. This morning there was no visible effect from the rain in the seepage areas. All have dried up. The rain did not seem to affect the flow out of the drain tiles.

4. Two more of the 23 drain tiles (8 now) have shown a decrease in flow.

5. Sand bleeding was initially identified in 5 drain tiles. Four of the five have stopped bleeding sand. BHLLC has measured the sand coming out of four drains for two-twenty four hour periods. The one remaining drain has only a trace amount left. We will continue this procedure.

6. There has been no change in the water level in the embankment piezometers.

BHLLC has completed the installation of three temporary observation wells, and will use this data in the stability analysis to be submitted in the near future.

There is little doubt that lowering the impoundment has had a positive impact on the condition of the embankment.

BHLLC’s vendor for graded sand material has begun delivering stockpiles of material to the Sanford dam area for the eventual construction repair work that will commence after the Labor Day holiday.

Lee W. Mueller, Architect & Co-Member Manager
Boyce Hydro, LLC
6000 South M-30 (P.O. Box 15)
Edenville, MI 48620
tel: (989) 689-3161 / fax: (989) 689-3055