Page 18 - Yucaipa Valley Water District

Director Memorandum No. 19-057 Page 4 of 7

Therefore, the original scope of services was developed to utilize a methodology with monitoring
wells that will be able to determine: the water mounding effect; the lateral movement of subsurface
water; the infiltration rate in the vadose zone; all used to calculate the specific yield and total
potential of storage when the spreading basins are constructed.

The District has received written authorization from the property owner to conduct the work at this
location.

On May 28, 2019, the District staff provided information to revise the original scope of services
from Geoscience to further our evaluation of the proposed project area. These tasks include:

Task 3 - Installation of Vadose Zone and Groundwater Monitoring Points

Overall, the construction of all of the monitoring equipment took longer than anticipated.
Additional drill rig time and installation time was needed because the drilling logs
suggested that there may be an offset in the subsurface soils along a fault and potentially

Yucaipa Valley Water District - June 4, 2019 - Page 18 of 237