DEP Project #: L-24441-24-A-N/L-24441-TF-B-N
Date: Thursday, 01-14-10 Time: 8:00-9:30 PM Report: 25
Observed by: Steve Roberge, PE Company/Agency: SJR Engineering Inc.
Weather Conditions: 20, Sun
General Contractor: Reed & Reed Civil Site Contractor: Sargent
Clearing Contractor: DGD Trucking/JML Trucking & Excavating
Contacts onsite: Ray (Reed+Reed), Chris (Sargent), Tracy (Sargent)
Date of Last Inspection: 01-05-10
Estimated # of days since last rainfall over ½”: more than a week
Photographs taken: 2 see attachments
The purpose of the site visit was to determine and document the effectiveness of the erosion control program being implemented at the project site and to insure the methods being used are being maintained. The site walk noted no significant erosion events.
Sargent has completed installing/maintaining erosion controls along the cleared/skidded sections of ROW and construction access from Tower 22 to Tower 8. The JML crew has completed the towers 1 through 7 skid road mulching and restoration for the North End access road up the mountain. The contractor is using hay mulch for disturbed surface cover in this area. The Contractor is shipping equipment home for the winter shutdown period. The project has finished earthwork construction from towers 16 thru 22 and the construction access road.
The following items were inspected:
1. Silt Fencing: The Contractor has completed installation of the silt fence and maintenance in order to shut down the project over the winter. The Contractor is keeping in mind that Spring conditions with snow runoff and Spring rains will contribute excessive amounts of water over the disturbed area. Stone water bars and cutouts in the road snowbanks will be made on the last pass down the mountain.
2. Stabilized Entrance: The Contractor has stone at the entrance to the project to minimize any tracking of soils. They have also installed additional crushed stone at the ends to bridges to minimize tracking of material onto the stream bridges and therefore into the stream.
3. Stockpile Area: The only onsite stockpile present consists of ledge/rock piles. No cover is necessary.
4. Mulching: Additional disturbed areas created during the construction activities this week have been covered with riprap and erosion control blankets. Sargent and JML Construction continued covering sections of exposed soils with a heavy hay mulch application in anticipation of a winter shutdown. All areas have been covered with a stabilized material.
5. Erosion Control Mix: The water bar outlets have erosion control mix or crushed stone installed to collect sediment. The erosion control mix at the outlet end of the water bars capture significant amounts of sediment in the grubbed areas of the crane access road. The Met Tower access road is to receive outlet protection such as the erosion control mix or stone check dams depending on the flow of water across the bars by the end of day tommorrow.
6. Dust Control: Not needed at this time.
7. Hay Bales: Hay bales have been installed in conjunction with silt fence in the areas near resources and along the downslope side of construction for the access road. This meets the requirements for double barriers protecting resources during winter conditions.
8. Stone Check Dam: The existing gravel access road has water bars with check dams being located in the ditch lines. The ditching along the upslope side of construction has stone check dams. The Contractor has all ditching lined with riprap along the construction access road and completed portion of the Mine Notch Road from Tower 22 to Tower 16/17 pad sites.
9. Culverts/Riprap: IF&W has not permitted an extension to the time window for installing culverts within streams. Other culverts have been installed within drainage paths as called out on the plans to the tower 16 pad site. All of the culverts have riprap inlet/outlet protection. Some of the larger culverts have a stone level spreader at the outlet end to disperse the water over a larger buffer area. The steam culverts are the only remaining pipe to be installed (to be completed in next construction season time window) within the disturbed construction area.
10. Level Spreader: Level spreaders have been constructed in several locations along the construction access road. Two remaining spreaders will be installed next construction season along the construction access road.
11. Water Bars: The gravel access road has erosion control devices such as drivable water bars with stabilized outlets (stone and/or erosion control mix check dams) being located along the steeper portions of the entrance road. Many additional water bars are located in the skidded and grubbed construction access road to allow upslope water easy passage across disturbed soils. The water bars have erosion control mix installed along the outlet end of the bars.
The Met Tower access road has been closed out (restored) for the full length of the road. The Contractor has installed many water bar diversions. The bars do not have any outlet protection such as rock check dams or erosion control mix installed at the end of the bars but is scheduled to have these installed by Friday night.
12. Catch Basins/Stormdrain system: All culverts (except in streams) have been installed along the construction access road and from pads 16 through 22.
13. Ditches/Swales: The gravel access road is being managed with proper erosion control devices including check dams being located in the ditch lines.
14. Groundwater seeps/Hidden Channels: The Contractor continues to note locations where seeps (ice) are visible. These have been marked for future considerations with regard to how the access roads are constructed (rock sandwich).
15. Cut/Fill Slope Protection: The Contractor has applied a hay mulch, rock riprap or hay blanket cover over disturbed soils throughout much of the active working project. Skidder trails have brush and/or corduroy placement in locations of steep slopes to minimize erosion at other locations. The Contractor has devised a system of water bars, bypass culverts/ditches, and sediment containment areas to limit erosion and sedimentation along disturbed soils. Construction of the Mine Notch Road from tower 16 through to tower 22 has a rock base as well as the section of the road between 16 + 17 tower pads. The Construction access road is completed with the exception of a few permanent stream culverts.
16. Vegetative Cover: Not applicable at this time.
17. Stream/Wetland Crossings: Bridging streams and matting wetlands are the only acceptable means for crossing at this time. IF&W has not extended the stream culvert placement window for this project. All in-stream work must be conducted between July 15 and September 30. All streams in the project construction windows are running clear. Streams flowing across the existing gravel road at the base of the mountain were running clear. There is no evidence of sedimentation occurring.
18. Spill Prevention: No evidence of any spills has been noted during this visit.
19. Winter Construction: The Contractor has been under winter construction requirements since November 1, 2009. The Contractor has completed preparing the project for a winter shutdown effective January 16, 2010. The collector line clearing/skidding operation will not continue into the winter months, and may be re-scheduled until next winter timneframe.
20. General nature of project: The project erosion control activities are current with the active work operations and have been adequately prepared for the winter shutdown period. Skidder trails 1+2 and the existing Met tower access road are restored and closed to traffic. The north access skidder trail (tower pads 1-8) has been completed. The access up the mountain in this area is restored.
21. Areas currently under construction/disturbance: Clearing activities and bridge construction over streams have been performed from station 1+00 along the construction access road to the Tower pads 16 through 22 including crane access road. The clearing crew has cut/skidded the main construction access road and Mine Notch Road from tower 1 to tower 22 and is complete. The ROW has been cut along the crane access road full length. No further disturbance is anticipated during this winter shutdown period lasting into May 2010.
22. Estimate total area under construction/disturbance: Station 1+00 through 80+00 of the construction access road construction is completed. Construction has been completed from tower 16 to tower 22 locations with the rock fill being placed along the road and towers 16 through 22, and the crane access road from 16 and 17, of the Mine Notch Road. Clearing/skidding operations are completed along the crane access path from one end of the project to the other. The Contractor has cut/skid/decked trees along the ridgeline from Tower 1 through Tower 12 and will bring them down the mountain along the crane road as it becomes available. The contractor has mulched the skidder trail along the ridgeline from towers 1-8, and has completed mulching the clearing/skidding/stumping disturbed areas from 8-15.
23. Comments: The erosion control program is effective and is being implemented as needed and necessary to control erosion during the construction of the project. The site remains frozen in at this point of time. No evidence of erosion or sedimentation have been observed during this site inspection. The project is now in winter shutdown mode.