water flow in the area. After the pipe is set, fill is placed around it and 

 packed. Provision for drainage varies considerably and is dependent upon site- 

 specific needs as well as the rights and authority the surface owner has for 

 land management. 



Depending on the type of fill, surfacing may be required. Usually it is 

 shell or crushed rock delivered by truck. The material is dumped on the base 

 and spread; no tamping is done since traffic will pack it down. Maintenance to 

 the right-of-way is usually minimal and limited to that necessary to keep the 

 road in good operating condition. 



On occasion, a roadway across marsh areas may be built entirely with fill 

 from outside the site. The main advantages to this method are that the fill 

 material may be selected to have a high load-bearing capacity - a limiting 

 factor with marsh soils - and environmental damage from borrow pits may be 

 avoided. However, in most areas the expense of this method is prohibitive. 

 The sequence of activities would be essentially the same as for road building 

 on upland soils, with all fill being trucked to the site. 



In most marsh areas, the base for roadways is made from the marsh soils 

 adjacent to the roadway (if an elevated base is used). After equipment is 

 moved to the site, a dragline begins excavation of borrow pits alongside the 

 road and heaps the material into a long dike. The fill is very plastic. It 

 may contain 50 to 88 percent water, and the soil portion may be 60 to 85 percent 

 organic matter (calculated from Penfound and Hathaway, 1938). The material is 

 difficult to dry and has a tendency to flow under heavy loads. 



Depending on the requirements of the surface owner and the exploration 

 company, conduits may be placed to allow water flow under the road. The surface 

 drainage patterns and low spots dictate the placement of drainage pipes. In a 

 few areas, surface owners have required the exploration company to build small 

 bridges over particularly critical drainage pathways. Bridge construction 

 requires pile drivers to drive foundation supports into the silt of marshes. 

 Many piles may need to be driven to give firm support. 



After the fill has been placed and drained for a short period, it may be 

 shaped by dozers and leveled. If the original intent was to provide only a 

 light-duty road, shell or gravel will be trucked in, dumped, and spread. 

 However if the road will bear heavy loads such as an entire rig, a board road 

 will be built. Levees bearing significant loads require a minimum top width of 

 6 to 7.5 m (20 to 25 ft) and should have 2:1 or 3:1 side slopes. 



Before the boards are placed, sheeting is put directly over the fill. 

 Polyethylene is used to exclude rain and thus keep the surface dry (Conner 

 et al . , 1976); however, in other places a mesh material is placed to stabilize 

 the surface. Large boards are placed in various patterns, depending on the 



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