Firewater run-off

Require detaiis of the adequacy of firefighting resources - personnei, foam, firewater etc, inciuding deaiing with firewater run off. 

Step 10 How will any firewater run-off be dealt with Hose and pumps will be necessary to transfer firewater run-off from the bund to another bund or catchment area. Alternatives include purpose-built bund overflows to a remote tertiary containment system, or increasing the capacity of an existing bund. Transfer could be by pumps or via gravity flow. 

Environmental consequences Volatile components will evaporate. Less volatile components will persist in the aqueous environment. Components will biodegrade with time. It is likely the contents will enter the river (if it is likely then addition containment must be provided). Firewater run off and FP foam would enter the drainage system and should be contained on site, eg shut Penstock to divert to firewater containment system. 

Identify watercourses, separators and plant drainage systems with the aim of minimising environmental pollution. Include areas where firewater run off can be contained. Identify equipment required to assist in this, eg drain sealing equipment, booms and fire service New dimensions pumping equipment. Consideration should be made of the resources held by Fire and Rescue Service (FRS) and how on-site resources will be used by FRS personnel. 

Pre-planned strategy to estimate the maximum quantities of firewater run off and to identify lagoon and catchment areas and size ... 

Details of on-site environmental protection measures, eg separators and areas where firewater run off can be contained. 

In some cases, particularly at smaller sites, containing contaminated firewater run-off will be considered to be impracticable because of cost and space considerations. In such cases, temporary containment systems or pollution control materials are available and should be used to minimise the environmental impact of firewater run-off. 

Sacrificial areas - the use of sacrificial areas involves the routing of firewater run-off to a designated, remote area, which is provided to allow infiltration of any contaminant and to prevent run-off from the site. The contaminant is often contained within a layer of permeable soil or other similar material and should be prevented from dispersing into other strata or ground water by an impermeable lining system which should be capable of containing both vertical and horizontal seepage. 

A main jet used for fire fighting produces large quantities of firewater run-off. In many cases, primary and local containment either by temporary or fixed bunding may prevent an incident from causing pollution. 

However, where local containment is not provided, or the fire risk assessment indicates that additional control measures are required, for example to contain firewater run-off, which may amount to thousands of cubic metres, remote containment systems may be appropriate. Remote containment systems may be used by themselves, or in combination with on-site containment arrangements. They may be required to protect both surface and foul water drainage systems. 

When considering the capacity required for containing firewater run-off, a distinction needs to be made between local and remote containment arrangements or combined containment in terms of what may be achievable. 

---