The sinking rate for two shafts at Bor project respectively exceeded 100m per month in June and July, despite of limited blasting time and vigorous measures over noise control, marking a solid step towards building an ecological mine.
As the contractor for developing air intake shaft and 2# air return shaft at JM mine of Bor Project, JCHX is challenged by strict noise and blast control requirements as both shafts are within short distance to local communities, particularly air intake shaft is only 100m away from the adjacent community. Hence, according to local standards the construction noise must be kept below 55db during daytime while zero noise is allowed at night.
After communicating with involved parties, blasting was allowed to be executed only from 9 am to 12 am. In order to maintain normal operations, achieve targeted blasting result within limited blasting time, and to minimize blasting impact on local communities, the controlled blasting method with small but frequent explosions was adopted.
On a very tight schedule and without any similar experiences to draw on, the management, technical and safety personnel on site were gathered to brainstorm and came up with solutions under the great support of supervisory divisions, through numerous trials and errors, the noise level was finally reduced to 54db through effective measures, including shortening blast holes depth, more holes with less charging, hole plugging with sand, placing water at shaft bottom, put bedquilt on collar steelwork, build soundproof walls and install rubber lining on tipping chute, etc.
Right at that time, Mr. Wang Xiancheng, Chairman of JCHX Group, sent his best regards and encouragement in person to the team on site, where he highly recognized their tremendous efforts in building ecological mines and maintaining good relations with local communities, his visit and words significantly inspired the project team to overcome all difficulties confronted.
While ensuring work safety, labor management was strengthened, procedures connection improved and cycle time strictly controlled to ensure blasting is executed within the required time slot and in strict accordance with local standards. Besides, daily work progress was strictly supervised to ensure targeted sinking rate was achieved per day. Under the above-mentioned efforts, it was recorded that a monthly sinking rate of 120.2m and 130.05m was achieved at air intake shaft (net Φ6.5m), while 105.6m and 112.43m was achieved at 2# air return shaft (net Φ7.0) respectively in June and in July, both exceeding the monthly target. In addition, our efficient measures taken in terms of noise control were recognized by the Client and promoted to the Client’s other projects.
The project will better their efforts in face of more arduous tasks and act proactively to contribute to the implementation of JCHX’s 5thFive-Year Development Strategy.
