The number of stations monitoring PM has been increased in 2001 from 13 to 35. As in the year 2000, highest PM pollution has been registered in Devnya, Vratza and Pernik.

PM10

Total number of MS - 35
Settlements - 18

Number of stations with exceedance of:

Automated - 11
Manual - 24

1h LV

not measured

24h average LV

This atmospheric pollutant is monitored at 35 stations. 23 out of the 35 have reported exceedence of the 24h.LV, and of the 24h.LV+AD. The highest concentrations are measured at the stations in Vratza and Bourgas. Maximum concentration was recorded in February in Vratza (AMS–50.6 times 24h.LV+AD), where concentrations exceeding the 24h.LV of 75mg/m³ have been registered in 14.4% of the days in the year.

Maximum measured concentrations (1 hour) of PM10 and the respective percentiles* for ten stations, 2001
Settlement/station	Maximum concentration µg/m³	Median - 50^th percentile µg/m³	98^th percentile µg/m³	99^th percentile µg/m³
Vratsa/AMS	3798	15	2819	3542
Bourgas/ AMS	1972	12	1972	1972
Plovdiv/Gigant	680	83	228	411
Montana/RIEW	496	90	496	496
Stara Zagora/RIEW	437	31	146	436
Gara Yana	397	91	340	397
Dolno Ezerovo/AMS	396	22	92	111
Devnya/AMS	296	58	143	158
Shumen/RIEW	278	52	255	278
Varna/Batak	258	60	163	205

On December 31, 2008 the requirement for the 24h. LV (50 mg/m³) not to be exceeded more than 25 times per one calendar year shall be enforced. Only 8 PM10 monitoring stations have registered compliance with this requirement in 2001. The highest numbers of exceedences have been reported for Pernik, Varna, Devnya, and Vratza.

The average annual limit value for PM10 has been exceeded at 20 stations. 14 stations have recorded exceedences of the av.an.LV+AD. The highest concentrations are observed in Bourgas (where the maximum average annual concentration – 297µg/m³- is recorded), Vratza, Sofia – Kremikovtsi, Plovdiv, and Montana.

Within the framework of a PHARE Twinning project with the German Ministry of Environment “Development of a pilot program for air quality management in the Municipality of Pernik” – a number of assessment activities have been carried out in 2001, among which were: air quality assessment, assessment of the monitoring equipment’s location and operational status, pollutant emissions inventory, and selection of a dispersal model for pollutants transfer assessment. The analyses of the assessments show that the PM10 pollution represents one of the main problems of the city’s air quality.

Figure 16 shows the monthly variations of the PM10 concentrations in Pernik for 2001.

The average concentrations in the respective period of measurements exceed the average annual limit value. The stations shown in the figure reflect the impact of all emission sources in the city and it is difficult to determine what are the respective emission shares of the industry, household heating, transport, and road pollution, which adversely affect Pernik’s air quality.

At the transport oriented monitoring stations no seasonal pattern of the concentrations has been observed, which indicates that transport is the main source of PM10 emissions. The highest concentrations have been registered during the weekdays, regardless of wind speed and direction.

Figure 17 presents in percentage the correlation between dust and PM10 concentrations at “Iztok” station in Pernik. During the summer (dry) months the percentage of PM10 increases considerably, which is related to the dusty motorways, and to pollutant transfer from other site sources.

Figure 17

The average correlation indicator between the concentrations of PM10 and total dust at “Iztok” station is 0.67. For comparison: in Sofia PM10 represent 0.5 -0.65% of the total dust quantity.

Last update on March 2003