Safety and emergency tools .1 Overview .1 Overview

Since all chemical industry sites have the potential to cause significant environmental harm and to threaten water supplies and public health, measures have to be taken to avoid the risks as far as possible or to react to accidents in such a way as to minimise their effects. Specific laws (especially the Seveso III Directive [ 145, EU 2012 ]) exist to prevent major accident hazards involving dangerous substances from occurring in the first place and, should they occur, to limit their consequences.

Spillages of chemicals and oil are obvious threats on chemical sites. However, materials which are not hazardous to humans may also cause serious environmental problems, as can the run-off water generated in the event of a fire. The environmental damage may be long-term and, in the case of groundwater, may persist for decades or even longer. Rivers, sewers, culverts, drains, water distribution systems and other services all present routes for the conveyance of pollutants off site and the effects of a discharge may be evident some distance away. In many cases, major pollution incidents can be prevented if appropriate pollution prevention measures are in place or immediately available. Contingency planning is the key to success and both preventive measures and incident response strategies as management tools need to be carefully addressed [ 74, Environmental Alliance (UK) 2000 ].

Pollutants may escape from the site into the water environment by a number of pathways, such as [ 74, Environmental Alliance (UK) 2000 ]:

 the surface water drainage system of the site, either directly or via off-site surface water sewers;

 direct run-off into nearby watercourses or onto ground, with a potential risk to groundwater;

 via the foul drainage system, with pollutants either passing unaltered through a sewerage treatment works or affecting the performance of the works, resulting in further environmental damage;

 through atmospheric deposition, such as vapour plumes.

Accidental gas releases to air normally need to be prevented by appropriate safety equipment and proper operation of the installations because, in most cases, gaseous releases cannot be caught. Exceptions are gases that can be mixed with water such as acids or ammonia, which can be dowsed by a water curtain and thus become an item for waste water treatment.

3.1.5.5.2 Managing firefighting water and major spillages Description

The main focus of firefighting water and spillage management is on containment strategies and equipment to handle these spillages. Other management tools, however, such as operational and strategic tools, should also be considered and supported by contingency or pollution incident response plans (see Section 3.1.5.5.3) to reduce the impact of any unplanned event that does occur [ 74, Environmental Alliance (UK) 2000 ].

The first step, however, is to consider the firefighting strategies and possible methods to reduce the amount of firefighting water run-off generated, e.g. by the use of sprays rather than jets, controlled burn and the possible recycling of firefighting water, where safe and practicable [ 74, Environmental Alliance (UK) 2000 ].

Containment systems

There will be one or maybe more levels of containment on chemical sites. In deciding the appropriate level of containment, a risk assessment is helpful (see Section 3.1.5.4.2). The operator should consider the hazardous materials on site, the risks posed by accidents, fire, flooding and vandalism, the likely failure mode of the primary containment (i.e. the tank or vessel in which the material is stored), the sensitivity of the receiving environment and the importance of preventing any resultant discharge to it.

In many cases, primary and local containment (bunding) will prevent an incident from causing pollution. However, where local containment is not provided, or risk assessment indicates that additional security is required, e.g. to contain firefighting water run-off which may amount to thousands of cubic metres, then remote containment systems may be employed. These may be used in isolation or in combination with local containment, for anything from a small area covering part of a site to a number of large individual installations. They may be required to protect both surface and foul water drainage systems [ 74, Environmental Alliance (UK) 2000 ].

The capacity needed for remote containment systems has to take into account:

 the potential harm that could be caused by the contaminated firefighting water (evaluation methods based on risk phrases – as defined in Regulation (EC) No 1272/2008 on classification, labelling and packaging of substances and mixtures [ 66, Regulation EC/1272/2008 2008 ] – can be used as well as systems like the German VCI concept on firefighting water retention capacity, where hazard classes are defined);

 the primary capacity (i.e. the capacity of the vessel in which the material is stored or handled);

 the potential amount of rainfall during the emergency event;

 firefighting and cooling water;

 foam (as a firefighting medium);

 dynamic effects, such as initial surge of liquid or windblown waves.

Remote containment systems can consist of:

 containment lagoons (or earth-banked containment basins), if the site topography and the ground and soil conditions are suitable, and the lagoons substantially impermeable;

 tanks, built for the purpose; their actual size, design standards and protective finishes influenced by the risk rating of the site, the retention time, the quantity and the nature of the materials stored;

 shut-off valves and penstocks, operated manually or triggered by means of automatic sensors, to isolate part of or the whole site;

 oil separators (see Section 3.3.2.3.3.8).

bunded area. In other cases, particularly at smaller sites, firefighting water containment facilities may be impracticable because of cost and space considerations. In such cases, temporary containment systems or pollution control materials should be considered [ 74, Environmental Alliance (UK) 2000 ].

Examples of emergency containment measures include [ 74, Environmental Alliance (UK) 2000 ]:

 sacrificial areas, designed to allow infiltration and to prevent run-off, equipped with an impermeable lining system to prevent dispersal into other strata or groundwater;

 bunding of vehicle parking and other hard standings;

 pits and trenches, equipped with a liner, particularly in areas of high groundwater vulnerability;

 portable tanks, overdrums and tankers.

Emergency materials and equipment

A variety of products are available to deal with spillages or to contain spills in emergency containment areas. Any materials or equipment used must be well-maintained and strategically placed at accessible locations which are clearly marked with notices explaining their use. The pollution incident response plan (see Section 3.1.5.5.3) should identify pollution prevention equipment and materials and their location. Such materials and equipment are [ 74, Environmental Alliance (UK) 2000 ]:

 sand and earth to soak up spillages of oil and chemicals and to use in sand bags;

 proprietary absorbents;

 sealing devices and substances for damaged containers;

 drain seals;

 booms.

Measures should be in place to dispose of, as soon as possible, any spillage, contaminated material or firefighting water. Where reuse is possible, the spilled material should be returned to storage on site. If off-site disposal is required, it can be done by means of [ 74, Environmental Alliance (UK) 2000 ]:

 an ordinary waste carrier;

 discharge to a foul sewer with the approval of the sewer operator;

 treatment of hydrocarbon-contaminated water with on-site oil separators.

Treatment/disposal has to take into account persistent and/or toxic contaminants that may also originate from firefighting foam materials (e.g. aqueous film-forming foams containing perfluorinated chemicals [ 82, Seow 2013 ]). As a precautionary measure, firefighting materials should be assessed to select the most suitable option with the least impact on the environment.

Achieved environmental benefits

The environmental benefit of the technique is to minimise the environmental impact of firefighting water and spillages.

Cross-media effects None considered important.

Operational data No information provided.

Economics

No information provided.

Driving force for implementation

Managing firefighting water and spillages is required to reduce the environmental impact of incidents/accidents.

Example plants

Seveso sites (high threshold) are example installations.

Reference literature

[ 66, Regulation EC/1272/2008 2008 ] [ 74, Environmental Alliance (UK) 2000 ] [ 82, Seow 2013 ]

3.1.5.5.3 Pollution incident response planning Description

A pollution incident response plan, as mentioned several times in Section 3.1.5.5.2, is mainly a strategy to spread all information needed in the most efficient way to all those whom it may concern. The general way to implement such a plan is by [ 75, Environmental Alliance (UK) 2000 ]:

 providing details of the site and of those for whom the plan is relevant;

 listing key contact numbers, such as emergency services, relevant environmental regulators, local water supply and sewer operators, EHS executives, keyholders and contact staff, specialist advisers, etc.;

 having ready a site drainage plan, containing a clear diagram of the site, showing layout and access details, off-site discharge points for surface water and trade effluent, etc.;

 providing an oil, chemical and product inventory of all substances stored on site, giving the maximum quantity likely to be stored, with data sheets attached;

 detailing emergency procedures, defining the scope of activities covered, staff responsibilities and the procedures for dealing with events such as spillages and leaking containers;

 giving rules on staff training and exercises to be carried out periodically.

All staff and contractors working on the site should be made aware of the plan and should know their role if an incident occurs.

An exemplary form of such a pollution incident response plan is given in Section 7.4, Annex IV.

Emergency planning and response is often an issue which needs to be coordinated at the site level. Sharing resources (e.g. containment systems, emergency materials and equipment, firefighter teams) and defining shared emergency procedures have important advantages.

Conventions established between operators of a site (see Section 3.1.3) are a way to clarify roles and responsibilities in this matter.

Achieved environmental benefits

Mitigating the effects on the environment of incidents/accidents.

Cross-media effects

There are no cross-media effects associated with this technique.

Operational data

Applicability

Applicable to all plants.

Economics

No information provided.

Driving force for implementation

The technique is required by legislation for the plants which have a high potential for pollution.

Reference literature

[ 75, Environmental Alliance (UK) 2000 ]

3.2 Monitoring

3.2.1 Overview

Monitoring forms a bridge between the inventory/register and operational tools (see Sections 3.1.5.2 and 3.1.5.3), but is also connected with strategic and safety tools (see Sections 3.1.5.4 and 3.1.5.5). The bulk of the information provided by inventory tools, e.g. the stream inventory/register (see Section 3.1.5.2.3), is collected with the help of monitoring systems and programmes. Probably the most important issue is controlling the proper operation of production and treatment processes, to check if the environmental targets set are met and to identify and help to track accidents (incidents).

To measure the effectiveness of an EMS, real data are required on the precise effects of the activities of the industrial site on the environment as well as on individuals. It is thus necessary to conduct a planned, regular sampling and monitoring programme. The parameters to be monitored should include [ 252, Ullmann's 2012 ]:

 point sources, diffuse and fugitive emissions to the atmosphere, water or sewer;

 wastes, particularly hazardous wastes;

 contamination of land, water and air;

 use of water, fuels, energy, oxygen, nitrogen and other gases (e.g. argon);

 discharge of thermal energy, noise, odour and dust;

 effects on specific parts of the environment and ecosystems (see e.g. Section 3.2.2.3);

 on-site accidents and near misses;

 staff injuries;

 transport accidents;

 complaints from community residents.

Monitoring, however, is not restricted to analytical measuring. It also includes regular maintenance, visual and safety checks.

Parallel to this document, a Reference Report on Monitoring of Emissions to Air and Water from IED installations (ROM) exists to which the reader is referred for further information [ 101, COM 2016 ]. Monitoring in the context of waste water and waste gas is further dealt with in Section 3.3.