November 6, Agenda

Transcription

1 Ohio Canal Interceptor Tunnel OCIT-2 Site OCITConstruction Update Public Meeting November 6, :00 pm November 6, 2014 Agenda OCIT Project Overview Purpose Noise Basics Noise Mitigation Measures Vibration & Blasting Basics Vibration Mitigation Measures Other Construction Impacts & Mitigation Measures Contracting Basics Site Specifics Page 2 1

2 OCIT Projects Overview Page 3 Purpose Proactive To Minimize Impacts to Community Impacts Noise Vibration Traffic, Road Detours, Towpath Trail Detours Dust Lighting How we Minimize Control Potential Impacts by Specification Require Special Mitigation Page 4 2

3 Purpose Ensure Compliance with Regulations and Best Practices City, State, Federal Consider lessons learned and successful practices on recent projects Page 5 Noise Basics Sound: Vibrations transmitted through a solid, liquid or gas, capable of being detected by human hearing. Decibel measurement is a logarithmic scale. For example: 70dB is actually 10 times larger in terms of sound pressure than 60db. Human Perception of sound is non-linear. For example: 70dB seems to be twice as loud as 60dB. Page 6 3

4 Noise Basics Table 2 Table 3 Page 7 Criteria Federal FHWA Highway Construction Noise Handbook FHWA-HEP ODOT adheres to Federal Highway (FHWA) noise standards OSHA noise levels for workers ASC Performed Noise Study Measured Ambient Noise Predicted Construction Noise Page 8 4

5 Federal Noise Standards Different standards for: Residential Commercial Industrial Noise to be Maintained Below Federal Standards for Residential Use (Most Restrictive) Day: (7am to 6 pm) 75dB or Ambient + 5dB Night: Ambient + 3dB Page 9 Noise Mitigation Measures Noise Requirements Equipment Enclosures to Reduce Noise Noise Reducing Bed Liners. Three-sided Enclosures around Compressors. Noise Dampening Enclosure around noisy equipment. Low Noise Equipment "Smart" Beepers on equipment Beep at 5 db above ambient noise. Noise Fences/Barriers 8-foot minimum required by City code. Site specific design of fences. Page 10 5

6 Mitigation Measures Sound Enclosure Page 11 Vibration Basics Vibrations are measured with a seismograph. Vibrations are expressed in terms of maximum velocity of vibrations. This is called Peak Particle Velocity (PPV). Blast overpressure changes with cloud cover. Humans are more sensitive to blasting than structures. Humans perceive blasting at 4 times lower levels than will begin to damage plaster. Page 12 6

7 Blasting Basics Blasting will be performed to excavate rock. Blasts will be down at bottom of shaft. Not more than one blast a day. Blasting can be less impact to community than rock excavation by Jackhammers, since large noise only happens once a day. Sound created like pop and thunder, can be influence by cloud cover. CSO Long Term Control Plan Program Management Team Page 13 Vibration Mitigation Measures Initial Test Blast Highly supervised by a licensed blaster Monitored to confirm blasting procedures before production blasting begins. Blast Design The maximum PPV recommended for the OCIT project is 1.0 /s, except for bridges and utilities, where a PPV limit of 2.0 /s will be applied. Blasting hours will be restricted as needed. Page 14 7

8 Vibration Mitigation Measures o Blast Security and Warnings City permit required. Public Notification. Sequence of Blast Horns before detonation Volume should be sensitive to the surroundings, but loud enough to warn abutters and construction workers. Visible signs on roadways and sidewalks Will warn motorists and pedestrian to be prepared for traffic closure. Traffic will be stopped for 5 minutes during blast event. 24-hour security when explosives are stored on-site. Page 15 Blasting Videos Blasting Setup Blasting noise Page 16 8

9 Other Impacts Traffic Defined Truck Routes Road Detours Towpath Trail Detours Other CSO Program Projects, City of Akron Projects, and private development will also have effects on traffic Lighting Direct lights away from residencies Reduce lighting to only security needs during non-work hours Dust Water will be used in construction for mitigation Trucks will be washed Street Cleaning shall be performed Page 17 Traffic, Lighting, and Dust Mitigation Measures Limit Working Hours 24 hours/day at portal site for tunneling only 7:00 am to 9:00 pm at other sites Routine Trucking Operations (7:00 am to 9:00 pm) In all cases, must comply with noise standards Direct construction lighting away from residential and commercial structures. Stormwater pollution prevention plans define how the Contractor will control dust at the site. Page 18 9

10 Contracting Basics Contractor will conduct pre and post construction surveys. 100 feet on each side of the projected centerline of the tunnel. 200 feet on each side of the shaft and portal footprint. Historic structure survey. Noise fences/barriers shown on plans will be constructed. Specifications require the contractor to: Not make noise above federal guidelines. Not cause vibrations beyond set limits. Conduct work only during defined work hours. Perform routine trucking only during defined trucking hours and on defined routes. Perform special mitigation work defined in Specifications. Page 19 Page 20 10

11 Site Specifics OCIT-2, R-19, Innerbelt Work Hours 7:00 am 9:00 pm Trucking Hours 7:00 am 9:00 pm (Rush hour restrictions) Blasting Hours (In Development) Noise Federal Guidelines Blasting 1"/sec Buildings and 2"/sec Utilities/Bridges Road Closures (5 minute Dart Avenue & Rand Avenue during blast) Enclosures around compressors and generators "Smart" Beepers Direct lights away from residences Pile driving enclosure Page 21 OCIT - 2 R18 DIV HAUL ROUTE INNERBELT SHAFT SITE HAUL ROUTE 1 HAUL ROUTE 2 R19 SHAFT SITE OCIT-2 SHAFT SITE Page 22 11

12 OCIT - 2 RACK 18 HAUL ROUTE HAUL ROUTE 1 INNERBELT SHAFT SITE HAUL ROUTE 2 OCIT-2 SHAFT SITE R19 SHAFT SITE Page 23 OCIT - 2 RACK 19 HAUL ROUTE HAUL ROUTE 1 INNERBELT SHAFT SITE HAUL ROUTE 2 OCIT-2 SHAFT SITE R19 SHAFT SITE Page 24 12

13 Questions? OCIT Project Manager: Michelle DiFiore, PE www. November 6,