MS (Distribution) UK Ltd.
These old timber air to ground towers were replaced by Sitenett in 2013 by two steel/timber hybrid towers and after 60 years of service, the two old timber communication towers were removed.
Removing the towers involved splitting each one into three sections and lifting each off with a mobile crane. As the towers were so old and were located on the coastline, the splice bolts had corroded to the plates and also swollen within the timber legs. This meant that the sections had to be separated by chainsawing the legs, with the weight supported by the crane. A second crane was used with a man basket to allow personnel access to the cut locations on the legs.
Each tower took half a day to prepare, which involved ensuring feeders and cable were cut at the correct locations, antenna booms & ladders tied into place and access holes cut into the platforms for lifting slings. Following the prep, both towers were removed in a day, with a further 2 days to prepare for transport and remove from site.
Sitenett also provided CDM Site Management and the H&S planning with the lift contractor.
The project was completed ahead of time and within budget.
In 2013 Sitenett was awarded a contract to dismantle 10 Orange PCS radio sites in Scotland. The sites comprised of a range of structure types from slim line and wide faced lattice towers to monopoles, with heights between 15-25m. The sites were located in varied locations including urban, green field and hilltop.
Depending on the requirements of the site provider, sites were to be decommissioned with varied levels of reinstatement ranging from leaving the fenced compound to complete removal and returning to green field status. Each site required the removal, processing and transport of the various elements including radio cards, cabinets, antennas and feeder cables prior to removal of the structure.
With a tight schedule, a rolling program was devised which saw a team of three multi-skilled personnel mobilised with welfare facilities and working from site to site utilising centralised transport and local contractors. Following the prep work, which generally took the first day on-site, the lifting arrangements and scrap transportation were arranged for the second day. Structures were removed, dismantled and cut up for transport on the second day, before moving onto the next site. Structure removal methods varied from use of mobile cranes, all terrain cranes, structure toppling and Helicopter lift.
The programme was completed successfully on time, on budget and led to a contract for a further three urban site decommissions in Wolverhampton, which were completed within a week.
As part of the Orange PCS decommission contract in 2013, a site located on a hilltop within the Alvie Estate near Aviemore was to be decommissioned, with removal of electronics, cabin and structure with top cover reinstatement of the foundations.
Access to the site was via a 40 min, off-road, 4x4 drive up a dilapidated mountain track, the largest piece of plant able to access the site was a small 3 ton excavator. With no method of transporting the cabin and structure down the hill and no method to bring soil back up, the only option was to completely dismantle the site into small loads and lift off with helicopter.
An advance party of three established the site and removed electronics and antennas over two days. The team were then joined by a further two personnel to assist with demolition of the structure & cabin then prepare for lifting.
Safety planning was paramount. Not only are there many risks associated with helicopter lifts in general, but with the team working in an inaccessible location, there was no margin for error. Exclusion zones, rescue plans, emergency services rendezvous points and robust communications were established.
With a mixture of helibag and sling loads prepared by the team the day before, the lift contractor attended the site for a final safety briefing followed by the commencement of the operation. Over 90 minutes, load after load was transferred from the hilltop to a large metal skip at the drop zone. With each return trip to the hilltop site being accompanied by a helibag filled with soil being dropped on the concrete tower foundation.
Every lift was executed exactly as planned and when the last lift was completed the only outstanding tasks were to spread the soil at the hilltop and have the skip container uplifted.
The project was completed on time and budget with involving no accidents or near misses.
Sitenett is a MS (Distribution) UK Ltd. company