061211-Environmental Screening Report-IMAE.pdf - nirb

document the quality of the completed work. Testing will be carried out byKnight Piésold personnel and may include in situ density, moisture content, grain sizeand specific gravity determinations.• Scheduling of construction, (i.e. work fronts) - will be dependent on available accessacross more significant drainages, prioritization due to foundation requirements andcoordination with any environmental or archaeological requirements of the constructionprogram.Representatives from Knight Piésold will oversee the Quality Assurance/Quality Control(QA/QC) of the road upgrades on a full-time basis, also providing the required support forfield fitting and ongoing design modifications/finalization based on the actual foundationmaterials and drainage crossing spatial limitations encountered at the time of construction.Office support will also be provided as required.2.14.5 Drainage Crossings Design and ConstructionAlong the alignment, 73 drainage crossings will require installation of structures to passrunoff flows during operation of the road. For 69 of these crossings, corrugated steelculvert pipes will be used, and modified sea containers will be used for 4 of the crossings.Many of the crossings will require multiple culvert installations in order to provide therequired capacity to pass the design flows.The design of the bulk sample road requires sizing of culverts and other structures for thevarious stream crossings to safely pass a specified design storm event. Contact withvarious government agencies for Nunavut did not disclose any established requirementsregarding hydrology design (design storm or flood return periods). Therefore, in lieu ofestablished design criteria for Nunavut, the design requirements for hydrology provided inthe Ministry of Natural Resources document “Guidelines And Criteria For Approvals –Under The Lakes And Rivers Improvement Act” (LRIA) were implemented for this project.The LRIA is an Ontario Government document that is used in Ontario to regulate designflood return periods for various road types and water crossing sizes. The design returnperiod requirements as presented in the LRIA are provided below:Crossing Size(Category)Design Return Period(Years)Small 1 in 10Medium 1 in 10Large 1 in 25Extra-Large 1 in 25Three major crossing types have been developed for application to the road, as follows:Page 23 of 169NB102-00181/6-1Revision 0November 20, 2006