The potential of naturally present bacteria to degradate the contamination in a (near) anoxic environment is stimulated by optimizing the conditions for degradation. In an anoxic environment degradation takes place mainly by reduction of the contamination. To stimulate this degradation process an electron donor is added to the soil. If there is a shortage of nutrients (nitrogen and phosphorus) they are also added. If the required bacteria are not in sufficient numbers present, they can also be added to the soil. In practice, stimulated degradation is mainly applied for the remediation of CVOC. Reductive dechlorination of CVOC occurs because specific bacteria break down organic matter (oxidation) and use the contamination as electron acceptor.
(Enhanced) natural attenuation, anaerobic
Enhanced biological anaerobic degradation can be applied for volatile chlorinated hydrocarbons (CVOC), HCH, mono-and dichlorobenzene, TEX and some pesticides. The technique can be applied in the saturated zone where the contamination is degraded in the soil and / or groundwater. A poor to well permeable soil is required. The technique is applicable to both the source and plume. The addition of the necessary compounds is often combined with pump & treat.
The duration of this technique depends on the size and type of contamination ranging from years to decades. Disturbance of the site is low. Infiltration takes place through injection filters or "direct push".
Related cases and HIP-pilots
Related cases: Almelo: CVOC**, Amsterdam (Asterweg): CVOC, BTEX and mineral oil***, Anaerobic and aerobic degradation, diverse contamination***, Anaerobic bioremediation of CVOC (The Hague)***, Apeldoorn (Deventerstraat 323a): CVOC ***, Den Bosch (de Kruithoorn): CVOC*, Den Haag (Boreelstraat e.o.): CVOC ***, Den Haag (W. Royaardsplein): CVOC ***, Ede: CVOC **, Geldrop (Peijnenburg): CVOC **, IJlst: CVOC **, Katwijk: CVOC ***, Leidschendam (Neherpark): CVOC and BTEX***, Terneuzen: CVOC and heavy metals: enhanced anerobic biological degradation, Veenhuizen (Norgerhaven): CVOC ***, Venlo: CVOC and zinc***, Wageningen (VADA): CVOC ***, Wageningen: CVOC and TEX ***, Wassenaar (Langstraat): CVOC**, Weesp In Situ Chemical Reduction Volatile Chlorinated Hydrocarbons ***, Zwolle (Dellen Wuyts): CVOC *
Related HIP-pilots: HIP-pilot Assessing stable end situation CVOC 1, HIP-pilot Assessing stable end situation CVOC 2, HIP-pilot Direct push shock load protamylasse – radius of influence and effect substrate, HIP-pilot Field comparison 2 substrates for anaerobic degradation CVOC, HIP-pilot Specific monitoring biological degradation