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~. PHASE II: Subsurface Drainage A subsurface drain Type 2 was required in the area .right of Sta 3+00 to 5+00 as high ground water was encountered. A neat trench was excavated three feet (3') wide, lined with Marifi 140-s filter fabric, backfilled with course rock and covered with topsoil. Post inspections of the area indicate the sub- surface water is being intercepted and drained cleanly to Curtis Creek. The subsurface trench drain left of road Station 17+00 to Sta 11+00 was placed to fifteen feet (15') deep. However, exca- vations were dry and did not show evidence of ground water. Filter fabric Marifi 140-s was used to line the trench and course aggregate backfill ~::a~ place,] as per plans to prevent any future underground water intrusion. All excavations were inspected and approved prior to backfilling. The trench drains right of ditch Station 9+ to 10+ was not re- quired due to the dry conditions encountered in trench con- struction, and the minimum flow expected north of the road. The trench drain right of ditch Station 17+ to 19+ was not re- quired as no underground water was encountered in this area. PHASE III: Surface Drainage Surface runoff will be collected in the watershed intercepting ditch described as shown on the plans from Sta 3+75 to 35+00 on Fig. 13.2.4. The intercepting ditch was staked and constructed with a depth of three feet (3') and side slopes ao shown .in Fig. 13.3.5. A11 areas in which the slope was 2% or greater, were ripraped with dry rubble five inches (5") thick. Planned culverts were placed right of ditch Sta 5+00, left of ditch Stations 8+00, 19+30, and 17+00, with hand operated com- pactors used to obtain 95% ASTM D-698 compaction. Emergency spillway culverts were placed as planned and shown on details L-26 and F-27. All backfill met the requirements of 95% maximum dry density before approved by the Inspecting Engineer. Riprap as shown in Figure 13.3.5. was placed upon Marifi 140-s, and field measured two feet (2') thick by the inspector. Gabion baskets were placed and backfi.l.l?d as per the plans and designated as "G", "I" and "H". See Fig. 13.3.5. for as con- structed detail`s. Planned and constructed sedimentation plans appear to be adequate for collection of runoff from disturbed areas until reve4itation ~ is completed and while the r.e£use pile is being constructed.