PERMFILE60741

• Permit No: M2006080
• IBM Index Class Name: Permit File
• Doc Date: 2/23/2007
• Doc Name: Response to Adequacy Review Comments of January 31, 2007
• From: WSI
• To: DRMS
• Media Type: D
• Archive: No

Square Feet of Slurry Wall/Linear Foot Total Linear Feet of Slurry Wall
Phase I 70.1 7,726
Phase II 82.5 4,643
6.4.6 EXHIBIT F -Reclamation Plan Maa
4. All of the maps have now been signed per Rule 6.2.1(b). The drawings also now more
clearly identify the 201-acre permit boundary and the slurry wall trench location. The legend
has been updated to assist with identifying these items.
6.4.7 EXHIBIT G -Water Information
5. Per Rule 6.4.7 (3)&(4), an estimate of the project water requirements and the projected
amount from each sources of water supply to the project, has been added to Exhibit G.
6. Bishop Brogden Associates, Inc. reports that the TSSP was filed with the OSE on February
8, 2007. No exposure of groundwater at the site or use of water requiring an approved
TSSP will occur prior to OSE approval. Additionally, the Green/Croissant Site SWSP
approved on January 22, 2007 provides for dust control water at the Bokelman/Walters Pit.
7. The Reclamation Plan map shows the proposed west and east drainage swales to be
constructed at reclamation for routing major storm events around the reservoirs.
Calculations for the excavation volumes for these channels and installation costs have been
added to the revised reclamation costs included with this submittal. These are primarily
grass-lined channels and the revegetation areas for the channels are wrapped into the total
reclamation revegetation areas for each phase.
8. Riprap Drain Outlet Protection Details have been added to Exhibit F -Reclamation Plan
Map. Outlet protection is provided for the perimeter drain outlets into the drainage swales
and to the Phase I -Cell 4 lake.
9. a) The predicted elevation change in groundwater levels due to mounding in the absence of
drain installation is a maximum of 9 ft along the south boundary of Phase I, 3.5 ft at the
Johnstown Waste Water Treatment Plant and 5-6 ft along the south boundary of Phase II. It
should be noted that the water table is confined along the south boundary of Phase I and
that the physical water table elevation would remain unchanged from historic, however the
pressure heads would increase in response to the dam effect of the slurry wall.
b) The drain performance was evaluated under two hydrologic scenarios, 1) local storm
rainfall events and 2) Big Thompson River flood wnditions. For local storm rainfall events;
Phase I West Drain Outlet -discharges into the Cell 4 lake. The outlet is not expected to
rgo submergence and will perform as designed under 10yr-100yr storm events.
WeilanrJ. inc. Bokelman-Walters Adequacy Response
environmental Tr Engineering February 20, 2007
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