JASKA-hanke 1
The Oil Pollution Compensation Fund finances the investigations and remediations of oil contaminated properties Oil Industry Service Centre and Pöyry Finland Oy provides the project management services Soili Programme 1996-2015 Oil contaminated properties: Gas stations, village shops, oil spills, garages Concentrates on risk zones groundwater areas, residential areas or properties near lakes, rivers or seas 22.3.2017/Pekka Huttula 2
Jaska in numbers ELY-keskus Suitable sites Applications Investigated Contaminated Remediated sites sites sites Etelä-Pohjanmaa ja Pohjanmaa 127 34 26 15 10 Etelä-Savo 20 6 6 2 1 Häme 47 18 17 5 2 Kaakkois-Suomi 159 53 34 13 7 Kainuu 57 24 15 6 2 Keski-Suomi 25 11 8 3 1 Lappi 49 30 19 11 1 Pirkanmaa 34 16 14 4 3 Pohjois-Karjala 46 22 19 9 4 Pohjois-Pohjanmaa 58 28 23 12 3 Pohjois-Savo 89 45 42 18 7 Turun kaupunki 15 5 5 0 0 Uusimaa 57 31 27 11 5 Varsinais-Suomi ja Satakunta 72 33 28 13 4 Yhteensä 855 356 283 122 50 22.3.2017/Pekka Huttula 3
Highly important in remediation projects Details of the former usage of the site Interviews Property owner, former owners, authorities, neighbours Old and new maps, pictures Investigations are based on the historical search Extent of investigation, number of soil and water samples, investigation pipe for groundwater, plan for sampling Soil / water /groundwater samples NP1-NP 6 = sample points, kaivo = well 22.3.2017/Pekka Huttula 4
Field analyzes (Petro Flag, PID) Laboratory analyzes Number and location of sample points is predeterminated Potentially contaminated areas Soil quality, groundwater information, sensations from soil samples The investigations are made to determine the boarders of the contamination Buildings, wells, water pipes Essential information for risk assessment Fraction of oil hydrocarbons (aromatics and aliphatics) Amount of organic carbon Soil quality, direction of groundwater flow Selection of the remediation technique and the remediation plan are based on the information from investigations Target levels for the remediation are presented in investigation report 22.3.2017/Pekka Huttula 5
The concentrations of oil hydrocarbons The distribution of gasoline (<C 10 ), middle (C 10 -C 21 ) or heavy (C 21 -C 40 ) distillates The area and depth of the contaminated area The soil qualities Groundwater level Property usage The target levels for remediated site Cost-efficient remediation 22.3.2017/Pekka Huttula 6
If the groundwater is contaminated Reliability of the remediation technique (references) Transportation distances to treatment centre/landfill Timetable Limited number of in situcontractors Underground oil tanks Sustainability of remediation method Opinions of the property owner Precious trees, fences, flowers etc. 22.3.2017/Pekka Huttula 7
About 40 % of all remediation sites are remediated by utilizing some of the in situ-methods Bioremediation/biostimulation/bioaugmentation Soil vapor extraction Electrical osmosis Chemical oxidation Usually combined with excavation 22.3.2017/Pekka Huttula 8
Hannu Silvennoinen, Nordic Envicon Oy 22.3.2017/Pekka Huttula 9
In situ is not cost-effective if there is only small amount of contaminated soil (under 200 300 t) High oil hydrocarbon concentrations (over 10 000 mg/kg C 10 -C 21 ) prevents the use of bioremediation Heavy distillates (only dig and dump) in situ is too slow Dense soil type (for example clay) Remediation time 1-2 years In general, in situ techniques are combined with excavation to reach the target levels Or risk assesment is utilized to determine the approvable remediation levels 22.3.2017/Pekka Huttula 10
Excavation Estimation 96 m 3 realization 45 m 3 22.3.2017/Pekka Huttula 11
Contaminated samples: NP 4 (0-1 m) PF2765 mg/kg, NP 7 (1-1,5 m) PF 2267 mg/kg, NP 8 (1-1.5m) PF 2551 mg/kg Soil type: silt, silty moraine Max. concentrations: C5-C10 370 mg/kg C10-C21 10 000 mg/kg C21-C40 1400 mg/kg Excavation 22.3.2017/Pekka Huttula 12
Contaminated area 20 m 2 Dig and dump 22.3.2017/Pekka Huttula 13
Estimated Realization Contaminated soil 20 m 2 10 m 3 itd 88 m 3 itd 15 t 105 t Max. concentration 750 mg/kg 9 800 mg/kg The rocks doubled the total remediation costs. 22.3.2017/Pekka Huttula 14
Gasoline (C 5 C 10 ) Middle distillates (>C 10 -C 21 ) Heavy distillates (>C21-C40) TPH (>C10-C40) Threshold value 300 mg/kg Lower guideline values 100 mg/kg 300 mg/kg 600 mg/kg Risk assesment can be utilized to determine the target levels for remediation or to determine the approvable level of remediation. Mostly the target levels are the national guideline values 0 1 m threshold value (normal use of the property) 1 m guideline values Limitations for choosing the remediation technique? 22.3.2017/Pekka Huttula 15
In situ-remediation: + The volume of contaminated soil has reduced by 60 70 % + The concentration of pollutants has dropped down remarkably after in situ, reduction 75 100 % + Cost saving 2 900 000 (VAT 0%) - compared to dig and dump - in 60 completed sites (in SOILI&JASKA) + The soil under buildings can be remediated without demolition works + Normal use of the property - Remediation time is longer (excavation few days, - Underground oil tank(s) excavation in situ 0,5-2 years) 22.3.2017/Pekka Huttula 16
BEFORE: Visit the site Contact the property owner Summary Description of the contaminated site (history) Soil quality, groundwater and surface water details Investigations and results Risk assessment Target levels for remediation Alternative remediation techniques are presented decision Working order, execution of remediation In situ-contactor makes a technical work spesification for the in situ-method Quality control Safety issues Monitoring, reporting, PR Timetable 22.3.2017/Pekka Huttula 17
Case Savo Varasto Maximum concentrations (lab) 626 mg/kg (C 5 C 10 ) 1 360 mg/kg (C 10 C 21 ) 190 mg/kg (C 21 C 40 ) 1 540 mg/kg (C 10 C 40 ) Asuinrakennus Maximum concentrations (lab) 14 000 mg/kg (C 5 C 10 ) 17 000 mg/kg (C 10 C 21 ) 1 000 mg/kg (C 21 C 40 ) 32 000 mg/kg (C 10 C 40 ) 22.3.2017/Pekka Huttula 18
In situ: Soil vapor vacuum extraction & soil disposal 22.3.2017/Pekka Huttula 19
Remediation area 1: 200 tonnes of contaminated soil (middle distillates 12 000 mg/kg) - excavation Remediation area 2: 900 tonnes of contaminated land (C 5 -C 10 > 7000 mg/kg) soil vapor extraction Required soil disposal after in situ Remediation area 1: 190 tonnes Remediation area 2: 580 tonnes (C 5 -C 10 concentrations 100 600 mg/kg) Cost saving app. 25 % 22.3.2017/Pekka Huttula 20
Soil vapor extraction has removed over 2 500 kg of volatile compounds (max. 35 kg/day) - 500 kg active carbon - 2 000 kg catalytic burner (high concentrations) SVE is still active. SVE combined with dig & dump (for the areas contaminated with heavy or middle distillates) 22.3.2017/Pekka Huttula 21
Yard House Groundwater area Soil is mainly clay Concentrations under building > 2000 mg/kg (C 10 -C 21 ) Groundwater is nearly in the same level as the basement floor (- 5 cm) The soil surrounding the house was removed Biostimulation (degradation of contaminants under building) The target level for groundwater is 50 ug/l 22.3.2017/Pekka Huttula 22
22.3.2017/Pekka Huttula 23