blast monitoring report - era

e m s

Pimlico Flats, no. 5,

Triq Viani,

Sliema, MALTA

Mob: +356 9944 5767

Email: [email protected] b l a s t m o n i t o r i n g s e r v i c e s

2020-11-09_HM22 Report.doc of 2

BLAST MONITORING REPORT

HM22 Hard Stone Quarry at Wied Filep, l/o Naxxar

9 November 2020

Details

Date 09-11-2020

Quarry number HM22 – Victoria Lines l/o Naxxar

Quarry operator Ballut Blocks Ltd.

ANFO Supplier Framegrip Ltd.

Police escort PC708 – M Vella

Location and Time of Blasting

Seven blasts were carried out between 11:58 and 11:24 at the points as approximately indicated on the

attached site diagram.

Summary of Blasting Conditions

Maximum charge per delay: upper area: 12.5 Kg, lower area: 25 Kg

Vibration limit: 4 mm/s (20 to 40Hz) at the nearest residential areas within 200 metres.

Air overpressure limit: 120 dB(L).

Site Specific Permit

All holes were within quarry boundaries and within the maximum depth allowed. Maximum charge per

delay was not exceeded. Blasting is carried out according to site specifications.

Weather Observations

Temperature: 21 C; Wind: NE 6 Kts Humidity: 79%, Pressure: 1023 hPa (source: maltairport.com

Current conditions as at c.12:00 9/Nov/2020) Cloud cover: 0%

Comments

Blasts number 1 to 4 are at the bottom benches and blasts 5 to 7 are at the middle benches of the quarry,

each at its respective location.

Notes about Monitoring

The seismograph was placed at No 7, Triq Sir Arturo Mercieca as indicated on the attached site diagram

as M3. The seismograph used is MiniMate Plus, serial number BE9488. The seismograph was set to

trigger at 0.50mm/s.

e m s

b l a s t m o n i t o r i n g s e r v i c e s

2020-11-09_HM22 Report.doc of 2

Readings

Blast Number 1 2 3 4 5 6 7

Time 11:58 11:58 12:00 12:07 12:13 12:14 12:24

Number of Holes 6 6 6 6 6 6 5

Number of Delays 6 6 6 6 6 6 5

Depth of Holes (m) 6 6 6 6 6 6 6

Max. Charge/Delay (kg) 10.5 10.5 11.5 11.5 11.5 11.5 15

Total Charge (kg) 63 63 69 69 69 69 75

Dist. from Seismograph (m) 190 190 180 180 180 180 180

Peak Particle Velocity (mm/s) 0.65 0.79 0.83 1.68 0.84 0.97 1.65

Frequency (Hz) 19.0 15.5 27.3 46 28.8 30.1 35.9

Air Overpressure (dB L) 101.9 104.2 104.9 102.8 105.5 104.9 102.8

Scaled Distance (m kg-½) 58.6 58.6 53.1 53.1 53.1 53.1 46.5

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 ½ unit, and depth in metres is rounded to the

nearest ½ unit. The plotting of the position of the holes on the attached site-diagram in relation to

quarry shape and other landmarks is not accurate and no site survey was carried out to plot these.

Displacement between the holes (as plotted on the diagram) and the seismograph is measured using the

online version of MEPA’s Map 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 (signed document

attached). Scaled distance and maximum 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 fly-rock outside the quarry boundaries. No damage to the surroundings was observed

after the blast.

_________________________

Anthony Cini

Event Report

Printed: December 22, 2020 (V 10.74) Format © 1995-2015 Xmark Corporation

Date/TimeTrigger SourceRangeRecord Time

Vert at 11:58:02 November 9, 2020Geo: 0.510 mm/s, Mic: 119.0 dB(L)Geo: 31.75 mm/s2.0 sec at 4096 sps

Serial NumberBattery LevelUnit CalibrationFile Name

BE9488 V 10.72-8.17 MiniMate Plus6.1 VoltsAugust 20, 2020 by Datum MonitoringK488IPOR.WQ0

NotesLocation: Quarry Blasting

Client:

User Name: ems

General:

MicrophonePSPLZC FreqChannel Test

Linear Weighting101.9 dB(L) at 0.825 sec2.7 HzPassed (Freq = 20.1 Hz Amp = 577 mv )

PPVZC FreqTime (Rel. to Trig)Peak AccelerationPeak DisplacementSensor Check Frequency Overswing Ratio

Tran0.60319.9

0.0150.0270.004

Passed7.53.9

Vert0.65119.0

0.1310.0270.005

Passed7.34.0

Long0.492

49-0.1180.0270.003

Passed7.34.2

mm/sHzsecgmm Hz

Peak Vector Sum 0.749 mm/s at 0.002 sec

BS 6472:1992 CURVE 32

Velo

cit

y (

mm

/s)

Frequency (Hz)

xy

z

1 2 5 10 20 50 100

1

2

5

10

20

50

100

200

254

Tran: + Vert: x Long: ø

No velocity above 1.00 mm/s

>

0.00.0 1.0 2.0

Trigger =

0.0AirOP

0.0Long

0.0Vert

0.0Tran

Time Scale: 0.20 sec/div Amplitude Scale: Geo: 0.500 mm/s/div Mic: 10.000 pa.(L)/div Sensor Check

Event Report



Long at 11:58:35 November 9, 2020Geo: 0.510 mm/s, Mic: 119.0 dB(L)Geo: 31.75 mm/s2.0 sec at 4096 sps


BE9488 V 10.72-8.17 MiniMate Plus6.1 VoltsAugust 20, 2020 by Datum MonitoringK488IPOR.XN0


Client:

User Name: ems

General:




Tran0.651

620.0760.0330.003

Passed7.53.9

Vert0.79415.5

0.1630.0400.006

Passed7.34.0

Long0.57125.3

0.0020.0270.004

Passed7.34.2

mm/sHzsecgmm Hz


BS 6472:1992 CURVE 32

Velo

cit

y (

mm

/s)

Frequency (Hz)

xy

z

1 2 5 10 20 50 100

1

2

5

10

20

50

100

200

254



>

0.00.0 1.0 2.0

Trigger =

0.0AirOP

0.0Long

0.0Vert

0.0Tran


Event Report





BE9488 V 10.72-8.17 MiniMate Plus6.1 VoltsAugust 20, 2020 by Datum MonitoringK488IPOS.1C0


Client:

User Name: ems

General:




Tran0.50831.5

0.0320.0270.003

Passed7.53.9

Vert0.58728.4

0.0760.0270.003

Passed7.34.0

Long0.82527.3

0.0370.0400.005

Passed7.34.2

mm/sHzsecgmm Hz


BS 6472:1992 CURVE 32

Velo

cit

y (

mm

/s)

Frequency (Hz)

xy

z

1 2 5 10 20 50 100

1

2

5

10

20

50

100

200

254



>

0.00.0 1.0 2.0

Trigger =

0.0AirOP

0.0Long

0.0Vert

0.0Tran


Event Report





BE9488 V 10.72-8.17 MiniMate Plus6.1 VoltsAugust 20, 2020 by Datum MonitoringK488IPOS.BO0


Client:

User Name: ems

General:




Tran0.905

730.0520.0460.004

Passed7.53.9

Vert1.33331.0

0.0970.0460.008

Passed7.34.0

Long1.683

460.0920.0600.006

Passed7.34.2

mm/sHzsecgmm Hz


BS 6472:1992 CURVE 32

Velo

cit

y (

mm

/s)

Frequency (Hz)

xy

z

1 2 5 10 20 50 100

1

2

5

10

20

50

100

200

254


x

x

ø

ø

>

0.00.0 1.0 2.0

Trigger =

0.0AirOP

0.0Long

0.0Vert

0.0Tran


Event Report





BE9488 V 10.72-8.17 MiniMate Plus6.1 VoltsAugust 20, 2020 by Datum MonitoringK488IPOS.MM0


Client:

User Name: ems

General:




Tran0.77835.9

0.0550.0460.003

Passed7.53.9

Vert0.76232.0

0.0330.0330.005

Passed7.34.0

Long0.84128.8

0.0440.0330.003

Passed7.34.2

mm/sHzsecgmm Hz


BS 6472:1992 CURVE 32

Velo

cit

y (

mm

/s)

Frequency (Hz)

xy

z

1 2 5 10 20 50 100

1

2

5

10

20

50

100

200

254



>

0.00.0 1.0 2.0

Trigger =

0.0AirOP

0.0Long

0.0Vert

0.0Tran


Event Report





BE9488 V 10.72-8.17 MiniMate Plus6.1 VoltsAugust 20, 2020 by Datum MonitoringK488IPOS.NF0


Client:

User Name: ems

General:




Tran0.778

760.0240.0460.002

Passed7.53.9

Vert0.96830.1

0.0560.0330.007

Passed7.34.0

Long0.92135.3

0.1330.0460.005

Passed7.34.2

mm/sHzsecgmm Hz


BS 6472:1992 CURVE 32

Velo

cit

y (

mm

/s)

Frequency (Hz)

xy

z

1 2 5 10 20 50 100

1

2

5

10

20

50

100

200

254



>

0.00.0 1.0 2.0

Trigger =

0.0AirOP

0.0Long

0.0Vert

0.0Tran


Event Report





BE9488 V 10.72-8.17 MiniMate Plus6.1 VoltsAugust 20, 2020 by Datum MonitoringK488IPOT.430


Client:

User Name: ems

General:




Tran1.65135.9

0.1000.0860.006

Passed7.53.9

Vert1.36522.0

0.0750.0730.008

Passed7.34.0

Long1.63539.4

0.0650.0730.005

Passed7.34.2

mm/sHzsecgmm Hz


BS 6472:1992 CURVE 32

Velo

cit

y (

mm

/s)

Frequency (Hz)

xy

z

1 2 5 10 20 50 100

1

2

5

10

20

50

100

200

254


+

+ ++++

xxxx

xø

ø

øøøø

ø

>

0.00.0 1.0 2.0

Trigger =

0.0AirOP

0.0Long

0.0Vert

0.0Tran


blast monitoring report - era

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