Project Name

1
Public Meeting Location January 31, 2007
Title page for audience

• Project Name
• Project Graphic

2
Blasting Operations Near Your Neighborhood
Public Meeting Location January 31, 2007

• My name is Thank you for coming!!
• I work for
• My role is
• You may contact me at

3
Who is in Charge?
Company Logo

• Contractor
• Project Name
• Project Contact
• Phone Number
• Contract/Permit number

4
Who Will Oversee the Project?
Company Logo

• Inspection Company
• Name
• Address
• Phone
• Regulators (Federal, State, local)
• Name
• Address
• Phone

Regulator Logo
5
Who will Conduct the Blasting?
Company Logo

• Company
• Blaster
• Address
• Phone
• Field office location
• Preblast Survey Company (if any)
• Name
• Address
• Phone

Company Logo
6
Who Will Evaluate the Blasting?

• Blaster
• Regulatory Agency
• Engineers and/or Seismic Specialists
• Name
• Address
• Phone
• Qualified /competent personnel

Company Logo
7
Project Overview

• Insert Project/Mine map or graphic or aerial
  photograph
• Discuss the purpose
• Discuss scope of work
• Discuss potential blasting sites
• All Companies Carry/Required Insurance

8
Why is Blasting Necessary?

• Discuss the project blasting
• Other options considered
• Ripping
• Rock Hammer
• Most Efficient
• Most Effective

9
How Will Blasting be Conducted?

• Safely with Modern Technology!

Todays Explosives are much safer than the old
dynamite and fuses seen in old Hollywood
movies We are professionals interested in sound
blasting practices that will minimize impacts to
you and your house
10
How is a Blast Designed?

• Holes will be drilled in a series of rows and
  loaded with explosives

11
What are the Important Parts of a Blast?

• The amount of explosives used in each hole
• Stemming confines the energy to the ground and
  eliminates flying debris
• All holes are connected and detonated
  independently
• The individual detonations focus the energy on
  breaking rock and help control vibrations (ground
  and air)

12
How Does a Blast Work?
13
How Will Our Blasting Look?

• Pick one or insert you own Blasting Video.

14
How Blasting Looks in the Movies!
15
Signage - For your safety!

• Heed warning signals
• Please keep off the project area

16
What We do to Protect You!

• Mark blast sites
• Guard entrances
• Block roads
• Sound warning signals

17
When Will Blasting Occur?

• Schedule
• Dates and times
• Daylight hours only
• Notification
• Letters, door hangers,
• Inform us of special needs
• Warning Signals
• Give Details

18
Will I Feel the Blasting?

• Probably
• Ground Vibrations
• Air Vibrations (Overpressure)
• If vibrations reach your property, they will
  cause your house to shake
• The amount of energy reaching your house is
  limited to prevent damage

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What are Blast Vibrations?

• Wasted Energy
• Elastic Motion
• Transient
• Come and go
• Like Ripples in a Pond
• Travel out in all directions
• Less Energy with Distance
• Size of the Stone (explosive charge) affects the
  wave size

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How Do Blasters Control Vibrations?

• The vibration strength is dependant on
• Charge size
• Distance from the blast
• Vibration speed limits apply to all residential
  structures
• Measure vibrations at the closest house for
  verification
• Ground movements - in thousandths of an inch
  Thickness of a piece of paper

21
How Far will the Vibrations Travel?

• Blast energy decreases rapidly with distance

22
Ground and Air Vibration Limits

• Ground Vibration Limit
• Air Vibration Limit
• Frequency considerations (road conditions)
• Monitoring for this Project at
• Residential structure
• Other structure

23
Blast Vibration Monitoring

• Blasting Seismographs
• Outside the House
• Ground Vibrations
• Air Vibrations

24
Where Will Monitoring Occur?

• At the closest house
• Must meet Project specifications or regulations
  at that location
• Add project map to facilitate discussion

25
Why use a Blasting Seismograph?

• Show compliance with the project limits
• Show compliance with the state limits
• Aid in post blast assessment / quality control
• Personnel performance
• Product performance

26
How do Blast Vibrations Affect My Home?

• Vibrations
• Cause structures to shake
• May be felt inside or outside
• House Vibration May Cause
• Rattling of Contents
• Annoyance
• Startle
• Understanding Vibrations from Blasting
• (Show now or after meeting)

27
How Much Will My House Move?

• House movements from blasting are measured in
  thousandths of an inch
• Houses undergo similar displacements on a daily
  basis because of
• Environmental effects
• Temperature changes
• Humidity changes
• Wind gusts
• Man-made effects
• People moving in the house
• Nearby traffic
• Stereo systems

28
What is Pre-Blast Survey?

• Home inspection prior to the start of blasting
• Base line survey of the existing condition of
  your house
• Notes
• Pictures
• Video
• Identify any unusual conditions about your house
  to help us protect your property
• While no damage to any structure is anticipated,
  if a claim is filed with us the pre-blast survey
  will be the base line for evaluating the claim

29
Summary

• Blasting will be done safely by competent
  professionals
• Blasting will be designed and conducted to
  prevent damage to property outside the project
  area
• Pre-blast surveys help us protect your property

30
Summary

• Vibrations are likely to be felt by nearby
  residents
• Perception is not a reliable indicator of damage
  potential
• If you have questions, do not hesitate to contact
  the professionals responsible for the project

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Our Goal

• As blasting professionals, we
  are interested in sound blasting practices that
  will minimize impacts to you and your house.

Questions?
32
Movies

• Explosives The Power Tool
• Short version
• Long version
• Understanding Vibrations from Blasting

33

• The following slide are available for inclusion
  if needed.

34
How Will Explosives be Transported and/or Stored?

• US DOT rules
• ATF rules
• OSHA/MSHA rules
• State regulatory authority
• State Fire Marshall
• Inspector and consultant oversight

35
What about Explosive Security?

• Security of utmost concern
• When on-site, explosives will be continuously
  attended
• No on-site storage over night

36
Are There Other Possible Side Effects of Blasting?

• Flyrock -
• Fumes -------------------
• Dust ---

37
What is Flyrock?

• Defined As Any Material
• Set in motion by the blast
• Traveling through the air
• Or along the ground
• Beyond the project area
• Not allowed to leave the project/mine site!
• Will video tape for post blast assessment
• If necessary, use mats to control

38
What are Fumes?

• A blast changes a solid or liquid substance into
  a gaseous substance
• Most byproducts are not harmful
• Nitrogen, Carbon dioxide, water
• Exceptions
• Carbon monoxide
• Nitrogen dioxide
• May ask to place a gas sensor in your house

39
Will Site Conditions Affect My Home?

• If the site frequency matches house frequency
• Structure resonate like a tuning fork
• Structures have natural frequencies from about
  4-12 Hz
• Blasting frequencies can range from 2-150 Hz
• Radio example if off a few Hertz the channel is
  not clear
• Perception within the house is not reliable
  indicator of regulatory compliance