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or localized complex recharge/discharge areas at the project property. The three general
trends that can be discerned in the data are discussed below.

Folling Wotor Qvel flnnos', Falling water levels observed in wells during 1992 are
indicative of discharging groundwater conditions following recharge to the system by

infiltrating rainfall. A total of 18, or over half of the monitoring wells at the project
property, fit into this general trend. Of these, eight wells demonstrated only steady decline
occurring from the initial April 10, 1992 to September 1992. These wells likely experienced
relatively early, rapid recharge from 1992 winter precipitation such that the recharge event

is not reflected in the time period covered in the well hydrographs. Most of these wells are
completed in San Gabriel basement underlying the crest of the East Firebreak Road
ridgeline, and include well MW-l8, well pairs MW-10/C-7A, MW-ll and also well MW-12,
which is located on a narrow spur trending southeast from the East Firebreak Road
ridgeline (Plate 7B). Declines in ridgeline well water levels were highest of all project
property wells, typically ranging from 15 to over 20 feet during the monitoring period.

Further downslope, the water level in shallow well MW-6B (of well pair MW-6A/MW-6B)
also steadily declined in 1992. Other wells experiencing a steady declining trend during this
period included well pair MW-17/MW-22 completed within alluvium in the Elsmere Canyon
drainage at the extreme northwest comer of the project property (Plate 78).

A second group of wells within the general falling water level trend showed either: 1) initial
steady conditions until decline beginning in mid-June; or 2) steady or slightly falling water
levels followed by an approximate 3 to 5-week period of rising water levels in July, or earlier
in May to June, then a return to declining conditions. In the first case, recharging effects
may not have been significant enough to be seen or may have occurred early with higher
water levels sustained for a period of time before discharging conditions became dominant. _

In the second case, recharge from the February/March precipitation apparently took longer
to reach some areas downslope of the main drainage divide.

Wells completed in San Gabriel Formation located below the East Firebreak Road
ridgeline, including MW-7, shallow well MW-3, well pairs MW-4/C-2, and shallow well

MW-3 (Plate 7B), typically showed a later recharging peak occurring in July. In the middle
to lower drainage areas of Elsmere Canyon, several wells and deep completions ofwell pairs
also apparently experienced delayed recharge from the winter precipitation, followed by
declining water levels. These include Towsley Formation completions, such as deep well

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