21Apr / 2015
How does continuous monitoring save you money?
Continuous ground-gas monitoring involves the use of unmanned data collection instrumentation. On the face of it, this can seem to be an expensive way to collect ground-gas data. Read on to find out why it can actually be the solution to saving you money.
Shortened monitoring periods
One benefit of using unmanned equipment is the ease of collecting data at a higher frequency. Hourly data is usually collected for each measured parameter as the frequency of environmental change does not often exceed 1 hour. This means that high volumes of data can be collected over shorter monitoring periods.
Cost of waiting
Typical monitoring periods run between 3 and 4 weeks, providing high atmospheric pressure variability is seen. This can provide a reduction in prescribed monitoring periods from 1 year to one month. There is a cost associated with waiting to develop on a brown field site, including cost of plant and workers. There is also a financial reward in selling new housing, which must be postponed if monitoring is holding up development. By reducing the necessary monitoring period to one month, the cost of waiting can be slashed and the financial rewards can be seen much earlier.
Fewer site visits
For a standard 4 week monitoring period, only 2 site visits are needed. Compared to 1 year of weekly periodic monitoring, this reduces the necessary site visits from 52 to 2. This saves significant travel, subsistence and accommodation costs, especially for those sites which are further away.
No need for over-design
Traditional ground-gas monitoring methods give us conservative estimates of the ground-gas risk. This often results in ground-gas protection measures being over-designed, wasting developers’ money on protecting against a risk which is not there. Continuous monitoring allows the full variability in ground-gas concentrations to be seen, multiple analytical tools can be run on the data and many lines-of-evidence allow the risk assessor to interpret the real ground-gas risk.
Vast cost reductions can be offered to developers in cases where the risk classification can be decreased, for example from an NHBC Amber 2, to an Amber 1 category.
Ground-gas protection membrane
Regulators, including the NHBC, environment agency and many local authorities are increasingly accepting of continuous monitoring. They see the strength in collecting high density, high quality data and understand that using this technique, monitoring does not need to go on for longer periods.