Impact of Falling of Ground in Underground Mines

8/12/2019 Impact of Falling of Ground in Underground Mines

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SEMINAR PRESENTATION

TOPIC:

ASSESSING THE IMPACT OF FALL OF GROUND IN

UNDERGROUND MINES

CASE STUDY: ANGLOGOLD ASHANTI, OBUASI MINE,

(SOUTH MINE).

by: Supervisor:

ROLANCE ABOAGYE FRIMPONG MR. E.M. BUABA


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OUTLINE OF PRESENTATION

Statement of the Problem

Objectives of the Project

Methods Used

Main Work

Observations

Conclusions

Recommendations


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STATEMENT OF THE PROBLEM

The mine produces about 395,000 tonnes of goldevery year.

The mine is divided into two main sections with

different blocks. These sections include; North Mine and South

Mine. The South Mine consists of GeorgeCarpendell Shaft (GCS) and Sansu Shaft. The North

Mine consists of Kwesi Mensah Shaft (KMS) andAdansi shaft.

The South section of the mine produces about60% of the total annual tonnage of the mine


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STATEMENT OF THE PROBLEM (contd)

Fall of ground remains one of the greatest hazards to

mine workers in AngloGold Ashanti (AGA) Obuasi

mine especially the South Mine.

This therefore necessitated the need to study itsimpact on the mine especially on production.


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OBJECTIVES OF THE PROJECT

To analyse the trend of fall of ground

To analyse the effect on production

To make appropriate recommendations to

reduce fall of ground


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METHODS USED

Review of relevant literature on fall ofground.

Acquisition of field data from AGA, Obuasimine.

Analysis of data acquired from the field.


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Fall of Ground (FoG) Accidents

Figure 1 FoG involving Scooptram machine


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Fall of Ground (FoG) Accidents (contd)

Figure 2 A FoG Incident Underground


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DATA ANALYSIS

Records of Fall of Ground (FoG)

0

1

2

3

4

5

6

Jan Feb Mar Apri May Jun Jul Aug Sep Oct Nov Dec

TotalFoG

Months

Fall of

Ground

(FoG)

Target

Figure 3 Total Fall of Ground (FoG) from January to December, 2009


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Record of FoG ( contd )

0

1

2

3

4

5

6

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

TotalFoG

Months

Fall of

Ground(FoG)

Target



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Record of FoG ( contd )

0

0.5

1

1.5

2

2.5

3

3.5


TotalFoG

Months

Fall of

Ground

(FoG)

Target



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INJURY RECORDS

0

0.5

1

1.5

2

2.5

Jan Feb Mar Apri May Jun Jul Aug Sep Oct Nov Dec

LostTimeInjuries(LTI)

Months

Lost TimeInjuries

(LTI)

Target

Figure 6 Total Lost Time Injuries from January to December, 2009


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INJURY RECORDS ( Contd )

0

0.5

1

1.5

2

2.5


TotalLostTimeInju

ries(LTI)

Months

Lost Time

Injuries

(LTI)

Target

Figure 7 Total Lost Time Injuries from January to December, 2010


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PRODUCTION IN STOPES WITH FALL

OF GROUND (FoG) INCIDENT

0

2000

4000

6000

8000

10000

12000

14000

Block 937 N 1

Sansu 218L

Sansu 218 N 1

Sansu 217 L

Sansu 323 L

Block8Upper

Block8Upper

21 N 1

Block8Upper

22 L

Block8Lower

30 N 1

Tonnageofore

Stopes

Budget

Achieved

Figure 9 Shows budget as against achieved tonnage of ore in stopes with FoG


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PRODUCTION IN STOPES WITHOUT

FALL OF GROUND (FoG) INCIDENT

0

5000

10000

15000

20000

25000

30000

Block 9

36L 9(283-276)

Block

8Lower32 N 2South

(333)

Block

8Lower30L

Block

8Lower30L

South

319

Block

8Upper23N 1South

315

Sansu 3

23 South183

Block

8Upper22 L N 1

South

Sansu 3

23LSouth

Sansu 2

20L N 1

Tonnage

ofore

Stopes

Budget

Achieved

Figure 10 shows budget as against achieved tonnage of ore in stopes without FoG


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IMPACT OF FoG ON THE MINE

PRODUCTION

Cost of operation

Dilution

Delay in mining


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OBSERVATIONS

The following observations were made during

the study and assessment;

There has been a decreasing trend of FoG

from 2009 to 2011.

Most of the support systems, particularly at

the areas of fall, were rusted.


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RECOMMENDATIONS

Workers should not be permitted to work in

areas that have not properly been scaled and

where no other forms of surface supportexist.

Mucking from the stope should be done withteleremote controlled scoops.


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THANK YOU !!!

Impact of Falling of Ground in Underground Mines

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