PHASES III & IV TRENCH BLASTING FOR SANITARY SEWER INSTALLATION - PowerPoint PPT Presentation

DC 02 & DC 03 SANITARY RELIEF PROJECT (BRENTWOOD BLVD – CONWAY ROAD) PHASES III & IV TRENCH BLASTING FOR SANITARY SEWER INSTALLATION

Agenda 2  Introductions  Goals  MSD’s Mission and Project Overview  J.H. Berra Const. Co., Inc.  Important Names to Mention  Project Description & Proposed Blasting Areas  Rock Excavation  Vibration and Vibration Monitoring  Pre-Blast Surveys & Damage Claims  Feedback and Questions

GOALS  Demonstrate to the City of Ladue officials the benefits of blasting vs. mechanically breaking the rock on this project  Receive “Zoning Approval Letter” from City of Ladue to allow blasting per St. Louis Country Regulations in order to maximize efficiency and minimize disturbance  Explain the requirements set forth by the Contract regarding blasting  Answer questions from City of Ladue regarding blasting procedures and regulations

MSD’s MISSION  “To protect the public’s health, safety, and water environment by responsibly providing wastewater and storm water management.”

PROJECT CLEAR Improve water quality in streams Investment of billions of dollars Required by US EPA and Missouri Coalition for the Environment. www.ProjectClearSTL.org

DC-02 & DC-03 SANITARY RELIEF PROJECT OVERVIEW  During heavy rains, the current sanitary sewer system can release sewage into creeks  Project Goal is to eliminate seven SSO by December 31, 2023  New larger diameter sewer from Brentwood & Manchester to Conway & Lindbergh. Excess flow will be stored in tunnel.  Phase I in Brentwood is complete. Phase II in Rock Hill and Ladue is under construction. Phase III & IV will begin soon.

J.H. Berra Construction Co., Inc. 7  Formed 1963  Successfully completed construction of DC 02 & DC 03 Sanitary Relief Phase 1  Employ approximately 150 employees  Employ (3) three Missouri Licensed Blasters

Other Key Players 8  Vibra-Tech  Pre-Construction / Pre-Blast Surveys  Vibration Monitoring / Blast Specialist  Austin Powder  Blasting Consultants  Supplier of Blasting Agents  St. Louis County – Mike Burkemper  Regulatory Agency for Blasting Operations

Project Description – Blasting  Includes approximately 7500 Lineal Feet of Trench Blasting (Total Project = ~ 18,000 LF)  Pre- Blast Surveys within 1000’ Radius of Any Planned Blast Location  Storage of Blasting Materials in accordance with St. Louis County  Blasting Operations in accordance with OSHA (Occupational Safety and Health Administration) and MSHA (Mine Safety and Health Administration)  Average Depth of Rock = 10’  Average Depth of Sewer = 22’

Deer Creek Trunk Sewer

Why we are here? Rock Excavation  Blasting v. Mechanically Breaking  Breaking – Hoe Ram  Loud  Continuous  Slow – 10 feet a day  Blasting  Less Noise  Less Disruption  Quicker – 40 feet a day

Schedule Impacts  7500 LF OF PROPOSED TRENCH BLASTING  BLASTING = APPROXIMATELY 200 DAYS TO COMPLETE  BREAKING = APPROXIMATEY 800 DAYS TO COMPLETE  BREAKING THE ROCK IN THESE AREAS CAN TAKE NEARLY 4X AS LONG AS BLASTING  IN PERSPECTIVE, IF A HOMEOWNER’S PROPERTY IS 200 LF LONG/WIDE, THE WORK WILL TAKE NEARLY 1 MONTH VERSUS 1 WEEK TO COMPLETE

Proposed Blasting Areas  Phase II upstream to Overbrook Drive  Litzsinger Road to Log Cabin Lane  City of Ladue Property Along S. Outer 40  Note:  There are specific areas along this alignment that will required mechanical means of rock excavation (i.e. Close proximity to houses, utilities, roadways, etc.)

Two Methods of Drilling & Blasting  Option #1:  Drill through the overburden (Dirt) and blast rock prior to any excavation taking place  Option #2:  Strip overburden (Dirt), drill rock, load holes, cover, then blast. Note: Option #1 is the preferred method; however, the condition of the overburden will determine if it is feasible

OPTION #1

Preparing to Blast

After Blast

Rock Excavation

Construction Complete

OPTION #2

Strip Overburden (Dirt), Drill, Load, Cover, Blast, Excavate, Install

Example Blasting Videos Video #1 – without pre-excavation Video #2 – with dirt backfill (Most Applicable to our Proposed Blasts) Video #3 – with blasting mats

So How Will MSD Protect Homes?  Notification before work begins  MSD CM team will monitor the contractors procedures  Adhere to Missouri Department of Public Safety and St. Louis County Blasting Requirements  Contractor Responsible for:  Secure / Safe Site  Homes Pre-inspected  Vibrations Monitored  Vibration Data Available as Requested

Structures from USBM RI-8507 2 Story Brick 2 Story Wood Frame Older Plaster- on-Lath Interiors 1 Story Wood Frame

FACTORS AFFECTING STRUCTURES PEAK PARTICLE VELOCITY FREQUENCY AIR OVERPRESSURE

USBM – SAFE LEVELS OF BLASTING VIBRATIONS FOR HOUSES 10 PARTICLE VELOCITY, in/sec 2.0 in/sec n i 8 0 0 . 0 1 0.75 in/sec Drywall 0.50 in/sec Plaster n i 0 3 0 . 0 0.1 1 10 100 FREQUENCY (Hz)

Vibration Standards 0.02 Initial Perception 0.50 Plaster on Lath (2 to 10 Hz) 0.75 Drywall (3 to 15 Hz) Mortar Joints 3.00 10.00 Reinforced Concrete 0.00 2.00 4.00 6.00 8.00 10.00

Remote Seismograph Monitoring Stations

Portable Seismographs

Air Overpressure Effects

Air Overpressure Level Comparisons Single Pane Glass 160 dBL Breakage Thunder 1000' 138 dBL State Limit 133 dBL Thunder 1/2 mile 124 dBL 0 0.05 0.1 0.15 0.2 0.25 0.3 P.S.I.

Saint Louis County Blasting Requirements Offer Pre- Blast Inspections Within 500’ Radius Ground Vibration Limit 2.0 ips Air Overpressure Limit 133 dBL

Pre-Blast Inspection Method of documentation may include digital photographs, video, audio description, photo log or diagrams of interior conditions and defects performed room by room, wall by wall Exterior conditions and defects are documented with digital photographs and/or video, including a photo mosaic

Property Owner Claims  Contact J.H. Berra Construction Co., Inc.  Kevin Bielicki – Project Manager  John O’Connor – Risk Manager  MSD Construction Management Team  J.H. Berra will reach out to the homeowner and will set up a meeting to survey the damaged areas  If necessary, a Post-Construction Survey will be offered to the homeowner for comparison  J.H. Berra will turn the claim over to its insurance agency which whom will perform the investigation and be in touch with the property owner  It is required by MSD to document all claims as they occur and the status of all claims is closely monitored by the CM Team

Feedback & Next Steps  Our Goals  Demonstrate to the City of Ladue officials the benefits of blasting vs. mechanically breaking the rock on this project  Receive “Zoning Approval Letter” from City of Ladue to allow blasting per St. Louis Country Regulations in order to maximize efficiency and minimize disturbance  Questions and Discussion

Thank you! 36 J.H. Berra Project Manager: Kevin Bielicki (314) 487-5617 Kbielicki@jhberra.com