Technical Information

We have put together the following guide to the practicalities of using the Synergistic System on contaminated soil projects. If you need any of these points elaborating on, contact us and we will gladly answer any questions.

Range of Contaminants

Our Synergistic System is effective against a wide range of hydrocarbon pollutants commonly found in soil, including:

• Aliphatic and aromatic compounds
• Fuel oils and crude oils
• Glycol and other solvents
• Certain halogenated compounds
• Alkanes up to C44H90
• Polycyclic aromatic hydrocarbons (PAHs)

Furthermore because of the special strains of pseudomonas and anthrobacter within BioBoost bacteria, the system will also now treat benzene, toluene, ethylbenzene and xylenes, the notoriously stubborn BTEX compounds.

Project Requirements

Sea-Chem will advise contractors on the volume of product required based on the nature of their project. However, as a guide, the follow should give some general idea of the volumes involved.

• Sea Power 101: 2L per cubic metre of soil to be treated
• BioBoost: 50g-150g (1 billion cfu/g) per cubic metre, depending upon the nature of the contaminants in the soil and the project's deadline

Application Methods

Our Synergistic System involves a single application of a pre-mixed solution of Sea Power 101. A typical application process is described below.

• Sea Power 101 is mixed at rate of 1:9 with cold water within an empty IBC, which when finished will treat 50 cubic metres of contaminated soil
• The prescribed quantity of BioBoost is then added, stirred and left to dwell for around an hour
• Contaminated soil is screened to remove rock and debris from the site
• Mixture of Sea Power 101 and BioBoost is then sprayed directly onto the screened material, with care taken to ensure even distribution (NB. most clients carry this out using a manual spray system, although some have developed techniques to utilise an automatic conveyor to improve efficiency)
• Treated soil is then placed into large windrows around 1m in height and left to attenuate naturally
• Some clients turn these windrows occassionally, usually ever 4 weeks, to allow air in to further accelerate the process
• Soil is tested and when considered safe either safely disposed of or backfilled

Please note that whilst the above description applies to a typical application of our Synergistic System, the products themselves are also compatible with almost all existing remediation methods and technologies, including direct surface application; in-situ injection (in sandy soils); and in-situ/ex-situ soil washing. Contact us for more details.

Financial Benefits

The Synergistic System allows bioremediation jobs to be carried out much more quickly than has previously been possible, which means that there are potentially huge operational savings to be had. Furthermore, using our products, full remediation and reuse of hazardous soil can be achieved for a fraction of the cost of diverting it to landfill. On very large jobs this saving can run into hundreds of thousands of pounds.

Environmental and Operational Benefits

Compared to remediation technologies that utilise hazardous chemicals, such as hydrogen peroxide, Sea-Chem's products are entirely free of warning stickers. They are neither toxic nor flammable, which means there are many health and safety (as well as financial) benefits to storing and handling these on a project site. Furthermore, as the products are totally biodegradable and sustainably harvested, they are currently the most environmentally responsible choice available to brownfield contractors.

Case Studies

Darlaston, West Midlands

There had formerly been a gasometer on this site, which had contaminated 3000 cubes of soil with an average TPH of 6,500mg/kg and an average PAH of 400mg/kg. Sanctus, the contractor for the work, were looking for a way of treating the soil on site and avoiding any landfill costs. We suggested to them that they apply two litres of Sea Power 101, our unique seaweed-based media, with 100g of BioBoost, a dried blend of pseudomonas bacteria, along with 18 litres of water for every cubic metre to be treated. This solution was then sprayed directly into the soil following screening. After the treatment was applied, the soil was placed into windrows and left for a period of twelve weeks. During this time, each windrow was turned twice. After a period of twelve weeks, the soil had been successfully brought down to safe levels and could be backfilled and compacted. The site is now ready for use by the adjacent school, Grace Academy.

Chertsey, Surrey

Tamdown won ‘Best Use of a Single Remediation Technique’ at the 2008 Brownfield Briefing awards for their treatment of this former gasworks in Surrey. After applying Sea Power 101 during the screening process, Tamdown constructed vented biopiles housed in large poly-tunnels. Air was continually circulated through the piles using a low vacuum extraction system, preventing the need for mechanical turning. Prior to the bioremediation, the site’s mean average contamination levels were 2,410mg/kg TPH and 1,100mg/kg PAH. Following treatment with Sea Power 101 over a period of ten weeks, these levels fell to just 394mg/kg TPH and 218mg/kg PAH respectively, representing a 90% reduction in overall pollution levels. Brownfield Briefing concluded that this was an achievement unlikely to be possible during the winter months by any other bioremediation method. Eliminating the need for the transportation and disposal of 200 lorry loads of hazardous waste to landfill and the importation of the necessary backfill, Tamdown’s bioremediation and re-use of 3,250 tonnes of soil resulted in a saving of £195,000, which equates to more than 50% of the total contract sum. For more information on this case study, please visit the Tamdown and Brownfield Briefing websites.

West Thurrock, Essex

Sea Power 101 was again able to prove its efficacy when it was utilized on a former industrial site in West Thurrock, Essex, under some extremely challenging conditions. Formerly a scrapyard, the contaminated site was heavily laden with diesel and other fuels. Prior to treatment the TPH of the soil ranged between 8,000mg/kg and 10,000mg/kg. Bioremediation took place between November and December 2010, when the weather in the southeast of England was extremely cold. Soil from the site was mechanically screened and then sprayed directly with Sea Power 101. It was then constructed into vented biopiles and left for a period of eight weeks. Soil samples were taken after the treatment period, and showed a new average TPH level of 775mg/kg, which represented a reduction in overall human-health contamination of 91.4%. The site also passed the stringent leachate targets for the soil of 930μg/l TPH. From seven leachate samples, the average contamination after eight weeks of treatment was 223μg/l, less than 25% of what was required. Given the exceptionally low temperatures during this period, our client had concerns about the level of microbial activity that could be expected at the site and about the effect that this might have on the speed and extent of the bioremediation. However, the results proved that even under these extremely testing conditions, Sea Power 101 dramatically enhanced the natural degradation process at the site. View full results data for the West Thurrock project.

Russian Air Base, Werneuchen, Eastern Germany

Land underneath this site had become contaminated over a long period of time by a mixture of lubricant oils, hydraulic fluids and aviation fuel. Following excavation, the soil applied with Sea Power 101 and formed into biopiles. The vast majority of hydrocarbons were removed in the first 30 days, and the site was fully remediated within four months.

Tar Works, County Durham

Heavy oils and other toxic materials had been contaminated an area of 20,000m² at this old industrial site. Soil was excavated, treated with Sea Power 101 and placed on windrows to accelerate the bioremediation process. The whole facility was successfully remediated after four months of treatment.

Private Property, Inverness

Following the failure of a domestic heating system, kerosene fuel had contaminated the ground underneath two private houses, producing a noxious atmosphere in one of them. Sea Power 101 was injected into the earth, along with oxygen, in a conventional in-situ process. The site was fully remediated with minimum disturbance to the residents.

Farmland, Avonbridge, Near Bristol

Failure of a valve on a brand new tanker carrying waste oils and diesel led to significant hydrocarbon leakage on this arable land. A very large excavation was carried out, and contaminated soil was placed in windrows and treated with Sea Power 101. Full remediation of the land was possible in six months.

Tar Factory, Rositz, Germany

This site had been producing tar for over 100 hundred years before it was decommissioned in 1992. During the Second World War, the factory was bombed causing extensive soil pollution, which was left untreated until the 1990s. Sea Power 101 was used on the site and showed itself to be highly effective in reducing the overall hydrocarbon content of the soil and in particular the notoriously stubborn PAHs.