Pollution Monitoring

• Air Quality
• Radiation Monitoring

Air Quality

The National Picture

In 1997, the Government published the UK National Air Quality Strategy. This report utilised Part IV of the Environment Act 1995 to impose a duty upon Local Authorities to review and assess air quality in their areas and, where government determined targets for prescribed pollutants are exceeded, to take action to reduce these levels by the target date. The pollutants comprise Benzene, 1,3-Butadiene, Carbon Monoxide, Lead, Nitrogen Dioxide, Particles (PM10) & Sulphur Dioxide. Since 1997, Local Authorities have therefore had to monitor/assess each prescribed pollutant within it's District and produce a sequence of reports which ultimately identify measures that would need to be taken in order to remedy any problem areas.

The Local Picture

The findings of the Stage 1 review and assessment of air quality within North Norfolk, published in March 1999, revealed a number of pollutants that required further investigation in order to assess whether the government determined targets would be met. These pollutants were benzene, nitrogen dioxide, sulphur dioxide and particles (PM10). Studies showed that NNDC could be confident that the other three pollutants would adequately meet their target.

The Council therefore proceeded to a Stage 2 review and assessment of the four pollutants of concern. This was published in April 2000 and concluded that the specified objectives for NO2, SO2, benzene and PM10 were predicted to be met. NNDC therefore identified that there was no requirement to proceed to a Stage 3 report and no Local Air Quality Management areas need be declared. Stage 1 & 2 reports are available on request - see Further Information for details on how to obtain these reviews.

Target dates for the prescribed pollutants range from end December 2003 to end December 2008 and hence, in order to ensure that NNDC is still on course to meet the objectives, the pollutants of concern continue to be monitored. These monitoring programs include NO2 as part of a nation wide survey, and benzene, SO2 & NO2 which are monitored specifically around the Bacton gas terminals. (PM10 has also been monitored at Bacton for a number of years but has now ceased due to consistently low levels being observed).

It is considered that out of the four key pollutants, nitrogen dioxide is of greatest concern as it is very closely related to vehicle exhaust emissions. Despite technology continuously improving such emissions, the number of vehicles on the road is only expected to increase. Hence NO2 monitoring will continue for the foreseeable future. With regards to the other key pollutants within the district, there are no proposals in place for the construction of any large industrial processes which could delecteriously change the predicted levels of these pollutants. These levels are therefore expected to remain on target. Nevertheless, should background levels increase for any reason then this adverse trend would be observed at the Bacton site where continuous monitoring will also persist.

Nitrogen Dioxide

NOx gases are formed during high temperature combustion processes from the oxidation of nitrogen in the air or fuel. The most common sources of NOx are power stations and vehicle exhaust emissions. NO is emitted in the greatest quantity but is relatively innocuous. Once liberated into the atmosphere, however, NO is converted into NO2 on contact with a suitable oxidant such as ozone. NO2 contributes to the production of photochemical pollutants and will eventually breakdown to produce nitric acid and hence give rise to acid rain.

Nitrogen dioxide is thought to affect human health by exacerbating respiratory disorders such as asthma. Atmospheric concentrations are generally well below the level at which damage to human health occurs but the effects of long term exposure are not yet fully understood.

Nitrogen Dioxide Monitoring

Since January 1995, NNDC has carried out monitoring of NO2 levels at selected locations throughout the district as part of the UK Nitrogen Dioxide Diffusion Tube Survey initiated by the Department of the Environment.

The aim of this national survey is to:

• Assess spatial and temporal distribution of NO2 concentrations in the urban environment.
• Highlight areas with elevated concentrations of NO2 which may warrent more detailed investigation.

In March 2000, the original six monitoring sites in North Norfolk were extended to eight. Four sites form part of the national survey whilst the other four sites provide additional data on NO2 levels in North Norfolk for the Council's own investigation.

There are several categories of site included in the national survey, they are as follows:

• Roadside - 1.5m from busy road
• Intermediate - 20-50m from busy road where a considerable number of people live
• Urban background - >50m from busy road in typically residential area

The four sites for the national survey are split into one roadside site, one intermediate site and two urban background sites and are located at the following addresses:

• Roadside - Cromer, Hamilton Road
• Intermediate site - Cromer, The Loke
• Urban Background sites - Cromer, Cliff Road, North Walsham, Corbett Road

The additional sites are located at Fakenham Infants School, Norwich Road (urban background); Horning Road, Hoveton (intermediate); Stalham Road South, Hoveton (roadside) and Stalham Road North, Hoveton (roadside).

Results

The table below shows diffusion tube results, in parts per billion (ppb), for year 2000 in North Norfolk for all eight monitoring sites.

Site Name	Min	Max	Average
Cromer 1	16	24	19
Cromer 2	9	17	13
Cromer 6	6	17	9
North Walsham 7	7	19	12
Hoveton, Stalham Rd South	23	30	27
Hoveton, Stalham Rd North	10	22	14
Hoveton, Horning Rd	9	19	13
Fakenham, Infants School	4	11	8

The following table presents a comparison of the annual averages of NO2 in ppb for the UK with those for North Norfolk. Data for all eight local monitoring sites have been utilised to provide the NNDC results.

Site	1997		1998		1999		2000
Classification	UK	NNDC	UK	NNDC	UK	NNDC	UK	NNDC
Roadside	23	21	23	18	23	26	20	20
Intermediate	16	14	15	13	15	13	14	13
Urban Background	13	10	12	11	12	12	12	10

These results show that the North Norfolk NO2 levels typically fall below the UK annual averages. The exception to this is the anomalous roadside value for 1999 which is attributable to the Hoveton, Stalham Road South site becoming one of the permanent monitoring sites.

The highest NO2 concentrations are found at the roadside sites which have an annual average of around 21ppb. As expected, the levels fall away with increasing distance from busy roads and hence the background sites have annual averages of around 11ppb. Only the Hoveton South site exceeds these averages.

The NO2 target values, as required by the Air Quality Regulations 1997, are 21ppb by 31 December 2005, measured as an annual mean, with a 1 hour mean of 105ppb not to be exceeded more than 18 times a year.

Our studies show that North Norfolk should fall within this objective by the target date. Further investigation will, however, be carried out in order to investigate the high NO2 levels at the Hoveton, Stalham Road South site.

For further information please contact the Pollution Control Team on 01263 516189 or 516301.

Radiation Monitoring

The Environmental Protection Team deals with queries regarding radiation in North Norfolk.

Work on radiation is categorised into:

• Gamma Radiation
• Non-Ionising (Electromagnetic) Radiation
• Radon Gas

Gamma Radiation

Gamma Radiation is a measurement of naturally occurring radiation background levels and is monitored by North Norfolk District Council on a routine basis, with results fed into a National Network. Radiation levels are measured in Micro Grays per hour.

After the Chernobyl accident in April 1986, many local authorities began to monitor background radiation at a local level. NNDC started monitoring at six sites throughout the district in 1991. After ten years of data collection it was decided to scale monitoring back to one site in Kelling, on a quarterly basis. As can be seen from the results collected, the background radiation levels have changed very little over the monitoring period.

As with other Local Authorities NNDC is a member of the Norfolk Local Authority Radiation Monitoring Group (NLARMG). This group aims to provide the other Councils and the general public with reliable and independent radiation data. NLARMG is affiliated to LARnet, the Local Authorities Radiation Network. They provide a sampling protocol which is audited on an annual basis. All the data collected is collated and sent to be included in the national database.

The results for the Kelling site since 2001, are detailed below:

Radiation Monitoring Results 2001 - 2006 for Kelling Heath Site

Year	Average	High	Low
2001	0.054	0.059	0.049
2002	0.056	0.059	0.052
2003	0.055	0.059	0.051
2004	0.054	0.058	0.052
2005	0.055	0.058	0.052
2006	0.054	0.055	0.054

Norfolk Local Authorities Radiation Monitoring Group (NLARMG) Report

The NLARMG annual report gives information about the radiation monitoring picture for the whole of Norfolk. Click here to access the latest report.

Non-Ionising Radiation

Non-Ionising Radiation is commonly associated with mobile phone masts.

NNDC does not currently carry out any monitoring for non-ionising radiation. We only provide information and redirect the public to Health Protection Agency (HPA) - Centre for Radiation, Chemical and Environmental Hazards (formally the National Radiological Protection Board (NRPB)). The HPA is the government's advisory body on radiation subjects.

For further information contact:

Health Protection Agency
Centre for Radiation, Chemical and Environmental Hazards
Chilton
Didcot
Oxon
OX11 0RQ
Telephone:01235 831600
Fax: 01235 833891
E-mail: rpd@hpa-rp.org.uk (Radiation Protection Division)

Radon

Radon Gas is a naturally occurring radioactive gas which is everywhere and is commonly raised as a query during house purchasing. Radon has no taste, smell or colour; in fact, special devices are needed to detect it. Radon is everywhere, usually at levels that pose negligible risk. Radon is formed when minute amounts of uranium present in all rocks and soils, decays. Radon is drawn into buildings mainly through cracks and gaps in the floor. In confined spaces such as homes, levels of radon gas can build up. Variations are on a very small scale: there may be different levels of radon even between neighbouring buildings.

There are some areas of the UK where the geology results in higher radon levels. From over 400,000 test results the Health Protection Agency www.hpa.org.uk/radiation has drawn up maps of radon affected areas. Most homes, even in these areas, will not have a radon problem but a proportion will. In many places radon is found in small pockets.

Radon levels are measured in Becquerel's per cubic metre (Bq/m3) of air and the level of 200 Bq/m3 in domestic properties has been considered the level at which action should be taken to reduce radon concentrate. This is known as the "Action Level".

The majority of North Norfolk has 0 - 1% of homes that are above the Action Level.
The current 2002 NRPB report indicates small areas of North Norfolk as "Radon Affected" www.hpa.org.uk/radiation/understand/at_a_glance/index.htm. The estimated number of houses within these areas likely to be above the Action Level is 1% to 3%. This equates to an estimated 12 to 36 homes within the areas as being likely to exceed the Action Level. These are areas around Wells, Cromer and between Bacton and Sea Palling.

The HPA have measured 190 dwellings within North Norfolk resulting in an average concentration of 31Bqm-3 with none at or above the Action Level. The highest value identified so far was in the order of 180Bqm-3 in the postcode district of NR21. These homes may be affected by radon to a level where the occupants, over the course of a lifetime, could be exposed to an above average risk of lung cancer. If you have concerns regarding radon and health see the Radon LA guide www.defra.gov.uk/environment/radioactivity/background/pdf/buyerseller-guide.pdf.

The only way of determining whether a property is above the "Action Level" is to undertake a test which costs £37.37, including VAT, and involves placing two small monitoring units in the home over a period of 3 months. The test will determine whether or not the property has a level of radon above the "Action Level". If this is the case then the HPA and/or this Authority can provide information on practical measures to reduce the build up of radon gas levels inside the property.

North Norfolk District Council do not carry out any monitoring for Radon, we rely on the information supplied to us by the HPA.

You can arrange for a test by contacting the Health Protection Agency, Centre for Radiation, Chemical and Environmental Hazards.

Homes that have been identified as having particularly high levels of radon can undertake simple, inexpensive and effective measures to reduce levels to an acceptable level. The work can usually be carried out by the homeowner or a builder. There are several different ways to carry out remedial work which would successfully reduce the amount of Radon in a home.

If you wish to speak to someone regarding Radon please contact a member of the Environmental Protection Team using the following contact details.

Telephone, Fax & Email:
Tel: (01263) 516085
Fax: (01263) 514627
Email: ep@north-norfolk.gov.uk

Our switchboard (01263 513811) operates from:
8:30am to 5:00pm Monday to Thursday
8:30am to 4:30pm Friday

Environmental Protection Team
Environmental Health Department
North Norfolk District Council
Holt Road
Cromer
Norfolk
NR27 9EN