11831 AIRPORT RD WHOLE SITE FILE 2020-01-21

7. Establish intermediate elevation benchmarks as needed to check work throughout the project. 8. Provide references for paving pins at 25-foot intervals or provide simultaneous surveying to establish location and elevation of paving pins as they are being placed. 9. For all other types of construction included in this provision, (including but not limited to channelization and pavement marking, illumination and signals, guardrails and barriers, and signing) provide staking and layout as necessary to adequately locate, construct, and check the specific construction activity. 10. Contractor shall determine if changes are needed to the profiles or roadway sections shown in the Contract Plans in order to achieve proper smoothness and drainage where matching into existing features, such as a smooth transition from new pavement to existing pavement. The Contractor shall submit these changes to the Project Engineer for review and approval 10 days prior to the beginning of work. 11. Establish, by placing hubs and/or marked stakes, the location with offsets of foundation shafts and piles. 12. Establish offsets to footing centerline of bearing for structure excavation. 13. Establish offsets to footing centerline of bearing for footing forms. 14. Establish retaining wall horizontal alignment. 15. Establish retaining wall top of wall profile grade. The Contractor shall provide the Contracting Agency copies of any calculations and staking data when requested by the Engineer. To facilitate the establishment of these lines and elevations, the Contracting Agency will provide the Contractor with primary survey control information consisting of descriptions of two primary control points used for the horizontal and vertical control, and descriptions of two additional primary control points for every additional three miles of project length. Primary control points will be described by reference to the project alignment and the coordinate system and elevation datum utilized by the project. In addition, the Contracting Agency will supply horizontal coordinates for the beginning and ending points and for each Point of Intersection (PI) on each alignment included in the project. The Contractor shall ensure a surveying accuracy within the following tolerances: Vertical Horizontal Slope stakes ±0.10 feet ±0.10 feet Subgrade grade stakes set 0.04 feet below grade ±0.01 feet ±0.5 feet (parallel to alignment) ±0.1 feet (normal to alignment) Swift Green Line—Corridor Stations Special Provisions SP19 May 2017