BLAST MONITORING REPORT. HG12 Hard Stone Quarry at Ta Klement, l/o Qala Gozo 22nd January 2016

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1 ems blast monitoring services Pimlico Flats, no., Triq Viani, Sliema, MALTA Mob: BLAST MONITORING REPORT HG Hard Stone Quarry at Ta Klement, l/o Qala Gozo nd January 06 Details Date Quarry number HG Ta Klement, l/o Qala Gozo Quarry operator Road Constructions Co. Ltd. ANFO Supplier Framegrip Ltd. Police escort PC 306 T Grech Location and Time of Blasting Five blasts were carried out between 3:39 and 3:49 at the points as approimately indicated on the attached site diagram. Summary of Blasting Conditions Maimum charge per delay: 70-90m: 3Kg; 90-0m: Kg; 0-30m: 3Kg, 39-0m: 4Kg; 0m: 60Kg. These distances are to be measured from the slipway and the girna. Vibration limit: 4 mm/s (0 to 40) at the nearest girna or the natural arch near the slipway. Air overpressure limit: 0 db(l). Site Specific Permit All holes were within quarry boundaries and within the maimum depth allowed. Maimum charge per delay was not eceeded. Blasting is carried out according to site specifications. Weather Conditions Humidity [] Wind [] Atmospheric Pressure Temperature [] Cloud Cover [] 66% 6 Knots ENE 06 hpa C clear [] As reported by weather.maltairport.com on Jan 06 at :0 at Luqa Airport [] Our observation Comments All holes are at the top shelf of the quarry. Blasts number and 3 and 4 and were grouped as two pairs and each pair was detonated by two short circuit eploders in quick sequence and captured as one event by the seismograph _HG Report.doc Page of

2 ems blast monitoring services Notes about Monitoring The seismograph was placed at the entrance to the girna. The seismograph was set to trigger at 0. mm/s. Instrument used is MiniMate Plus, serial number BE9488. Readings Blast Number 3:39 Time 3 4 3:39 3:49 No. of Holes 6 6 No. of Delays 6 6 Depth of Holes (m) Ma. Charge per Delay (kg) Total Charge (kg) Dist. from Seismograph (m) (mm/s) Air Overpressure (db L) Scaled Distance (m kg-½) Burden is an average of metres, and distance between holes is an average of.3 metres. Weights in kilograms are rounded-up to the nearest unit, and depth in metres is rounded to the nearest ½ unit. Displacement between holes and the seismograph is measured using the online version of MEPA s Map Server and is accurate to the nearest 0 metres. Number of holes, their depth, burden, and the amount of ANFO used are as given by the quarry operator. Scaled distance and maimum charge per delay are calculated from the primary data. Weights are rounded-up to the nearest kilogram and the depth is rounded to the nearest ½ meter. Observations There was no flyrock outside the quarry boundaries. No damage to the surroundings was observed after the blast. The generated by blasts,, and 3 eceeded the 4mm/s limit. Air overpressure limit of 0dB was eceeded by blasts, 3, 4, and. It is suggested that the charge per delay should be reduced by drilling holes that are closer together and have less burden, since reducing depth is not practical in this area of the quarry Anthony Cini Anthony Cini B.Sc _HG Report.doc Page of

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5 Event Report Date/Time Trigger Source Range Record Time at 3:39:43 January, 06 Geo: mm/s Geo: 3.7 mm/s.0 sec at 4096 sps Serial Number Battery Level Unit Calibration File Name BE9488 V MiniMate Plus 6. Volts August 0, 0 by Datum Monitoring K488G7IL.Y70 Notes Location: Quarry Blasting Client: User Name: ems General: Microphone PSPL Channel Test Linear Weighting 9.4 db(l) 8.7 pa.(l) at sec 30.6 (Freq = 0. Amp = 7 mv ) BS 647:99 CURVE 3 Time (Rel. to Trig) Peak Acceleration Peak Displacement Frequency Overswing Ratio Peak Vector Sum.430 mm/s at 0.47 sec mm/s db sec g mm Velocity (mm/s) 0 y 0 z > : : : AirOP.0.0 Time Scale: sec/div Amplitude Scale: Geo:.000 mm/s/div Mic: 00 pa.(l)/div Trigger = Printed: March 4, 06 (V 0.74) Format 99-0 Xmark Corporation

6 Event Report Date/Time Trigger Source Range Record Time at 3:39:7 January, 06 Geo: mm/s Geo: 3.7 mm/s.0 sec at 4096 sps Serial Number Battery Level Unit Calibration File Name BE9488 V MiniMate Plus 6. Volts August 0, 0 by Datum Monitoring K488G7IL.YL0 Notes Location: Quarry Blasting Client: User Name: ems General: Microphone PSPL Channel Test Linear Weighting 7. db(l) 4. pa.(l) at 0.7 sec 33.6 (Freq = 0. Amp = 7 mv ) BS 647:99 CURVE 3 Time (Rel. to Trig) Peak Acceleration Peak Displacement Frequency Overswing Ratio Peak Vector Sum. mm/s at 49 sec mm/s db sec g mm Velocity (mm/s) 0 y 0 z > : : : AirOP.0.0 Time Scale: sec/div Amplitude Scale: Geo:.000 mm/s/div Mic: 00 pa.(l)/div Trigger = Printed: March 4, 06 (V 0.74) Format 99-0 Xmark Corporation

7 Event Report Date/Time Trigger Source Range Record Time at 3:49:8 January, 06 Geo: mm/s Geo: 3.7 mm/s.0 sec at 4096 sps Serial Number Battery Level Unit Calibration File Name BE9488 V MiniMate Plus 6. Volts August 0, 0 by Datum Monitoring K488G7IM.FA0 Notes Location: Quarry Blasting Client: User Name: ems General: Microphone PSPL Channel Test Linear Weighting 3.7 db(l) 30.7 pa.(l) at sec 7.3 (Freq = 0. Amp = 7 mv ) BS 647:99 CURVE 3 Time (Rel. to Trig) Peak Acceleration Peak Displacement Frequency Overswing Ratio Peak Vector Sum.8 mm/s at sec mm/s db sec g mm Velocity (mm/s) 0 0 y z > : : : AirOP.0.0 Time Scale: sec/div Amplitude Scale: Geo: 0 mm/s/div Mic: 00 pa.(l)/div Trigger = Printed: March 4, 06 (V 0.74) Format 99-0 Xmark Corporation