BLAST MONITORING REPORT. Four blasts were carried out between 10:56 and 11:09 at the points as approximately indicated on the attached site diagram.

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1 ems blast monitoring services Pimlico Flats, no. 5, Triq Viani, Sliema, MALTA Mob: BLAST MONITORING REPORT HM26 Hard Stone Quarry at Tal-Maċina, Nigret, l/o Żurrieq 16 May 2018 Details Date Quarry number HM26 Tal-Maċina, Nigret, l/o Żurrieq Quarry operator C J C Camilleri Bros. Ltd. ANFO Supplier Framegrip Ltd. Police escort PC139 W Spiteri Location and Time of Blasting Four blasts were carried out between 10:56 and 11:09 at the points as approimately indicated on the attached site diagram. Summary of Blasting Conditions Maimum charge per delay: 50Kg Vibration limits: 4 mm/s (20 to 40) at the nearest sensitive point within 200m. Air overpressure limit: 120 db (L). Site Specific Permit Holes were within quarry boundaries and within the permitted depths. Blasts were carried out according to the site specific conditions, and no blast eceeded the maimum permitted charge of 50Kg per delay. Weather Conditions Cloud Cover: 100% covered Temperature: High 20C, Low 13C, Wind: WENW F4 5 (maltairport.com/weather, 9/Apr/2018) Comments Blast are at bottom shelves of the quarry at their respective locations _HM26_Report.doc Page 1 of 2

2 ems blast monitoring services Seismograph was placed at the front of the Nigret booster. Seismograph was set to trigger at 0.50 mm/s. Seismograph used is MiniMate Plus s/n BE9488. Readings Blast number Time 10:56 10:57 11:09 11:09 No. of holes No. of delays Depth of holes (m) Ma. Charge per delay (kg) Total charge (kg) Dist. From Seismograph (m) (mm/s) Frequency () Air Overpressure (db) Scaled Distance (m kg -1/2 ) Burden is an average of 2 metres, and distance between holes is an average of 2.5 metres. Weights in kilograms are rounded-up to the nearest half-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 PA s Geo Server and is accurate to the nearest 10 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 quarry boundaries. No damage to the surroundings was observed after the blast. Further Comments about Eceedance of by Blast number 3 Blast number 3 has eceeded the limit of 4 mm/s. Blasts number 3 and 4, but more so blast number 3 is in the sensitive location at a corner which has in the past caused eceedances in ground vibrations and was noted in the blasting method statement of Since those occurrences of high, the operators have opened a new bench with a reduced height and managed to bring down the charge per hole from around 50 kg to around 30kg. These actions are clearly not enough to consistently and reliably reduce vibration to a level within the limits set by ERA because vibration levels are very often very close to 4mm/s and eceedances are styill _HM26_Report.doc Page 2 of 3

3 ems blast monitoring services somewhat common in this particular area. (Other areas like that of blasts 1 and 2 generate reliably lower and no action need to be taken about them.) It is being suggested that: 1. Charge per delay is further reduced. This could be achieved by: a. reducing the burden while still making sure that the blasts cut the rock effectively or otherwise poorly cut rock will become a serious danger to quarry personnel. b. reducing the borehole depth while maintain the current burden and stemming practices. This is safer than option (a) c. applying both (a) and (b) 2. Ideally, also, the operators should consider flipping the blast direction around so that blasts back away from the houses, like blasts number 1 and 2 of this blasting session. This may be achieved by digging a trench using mechanical means (e.g. hydraulic hammer) at the northern border and then apply eplosives to cut stone so that the product fills the trench. This is hardly possible with this current bench but may be a consideration for future benches in this area. 3. It is also strongly suggested, whether the latter suggestion is possible or not, that new benches in tis sensitive area are shallower and should measure around 9 metres so that each hole will take between 20 and 25 kg of ANFO. Anthony Cini B.Sc _HM26_Report.doc Page 3 of 3

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5 Event Report Date/Time Trigger Source Range Record Time at 10:56:53 May 16, 2018 Geo: mm/s, Mic: db(l) Geo: mm/s 2.0 sec at 4096 sps Serial Number Battery Level Unit Calibration File Name BE9488 V MiniMate Plus 6.1 Volts August 17, 2017 by Datum Monitoring K488HEZ7.QT0 Location: Quarry Blasting Client: User Name: ems General: Microphone PSPL Channel Test Linear Weighting db(l) pa.(l) at sec 5.2 (Freq = 19.7 Amp = 564 mv ) BS 6472:1992 CURVE 32 Time (Rel. to Trig) Peak Acceleration Peak Displacement Frequency Overswing Ratio Peak Vector Sum mm/s at sec mm/s db sec g mm Velocity (mm/s) y z > Frequency () : : : AirOP Time Scale: 0.20 sec/div Amplitude Scale: Geo: mm/s/div Mic: 100 pa.(l)/div Trigger = Printed: May 22, 2018 (V 10.74) Format Xmark Corporation

6 Event Report Date/Time Trigger Source Range Record Time at 11:09:30 May 16, 2018 Geo: mm/s, Mic: db(l) Geo: mm/s 2.0 sec at 4096 sps Serial Number Battery Level Unit Calibration File Name BE9488 V MiniMate Plus 6.1 Volts August 17, 2017 by Datum Monitoring K488HEZ8.BU0 Location: Quarry Blasting Client: User Name: ems General: Microphone PSPL Channel Test Linear Weighting db(l) pa.(l) at sec 12.3 (Freq = 19.7 Amp = 564 mv ) BS 6472:1992 CURVE 32 Time (Rel. to Trig) Peak Acceleration Peak Displacement Frequency Overswing Ratio Peak Vector Sum mm/s at sec mm/s db sec g mm Velocity (mm/s) z > y Frequency () : : : AirOP Time Scale: 0.20 sec/div Amplitude Scale: Geo: mm/s/div Mic: 100 pa.(l)/div Trigger = Printed: May 22, 2018 (V 10.74) Format Xmark Corporation

7 Event Report Date/Time Trigger Source Range Record Time at 11:09:57 May 16, 2018 Geo: mm/s, Mic: db(l) Geo: mm/s 2.0 sec at 4096 sps Serial Number Battery Level Unit Calibration File Name BE9488 V MiniMate Plus 6.1 Volts August 17, 2017 by Datum Monitoring K488HEZ8.CL0 Location: Quarry Blasting Client: User Name: ems General: Microphone PSPL Channel Test Linear Weighting db(l) pa.(l) at sec 47 (Freq = 19.7 Amp = 564 mv ) BS 6472:1992 CURVE 32 Time (Rel. to Trig) Peak Acceleration Peak Displacement Frequency Overswing Ratio Peak Vector Sum mm/s at sec mm/s db sec g mm Velocity (mm/s) 20 y 10 5 z > Frequency () : : : AirOP Time Scale: 0.20 sec/div Amplitude Scale: Geo: mm/s/div Mic: 100 pa.(l)/div Trigger = Printed: May 22, 2018 (V 10.74) Format Xmark Corporation