Leaks and spills - LNAP and DNAPL detection and clean up  

Any tank can leak. Most leaks can be cleaned up and responsible operators need equipment that does what’s needed. With an ATEX Zone 0 certified interface meter site operators can successfully achieve LNAP and DNAPL detection when monitoring petrochemical sites, tank farms, petrol station forecourts, landfills or remediation sites. If site technicians detect leaked product with an interface meter they can measure its depth and thickness, grab a sample with a bailer and extract product with a skimmer and bladder pump or product and water with a total fluids pump. While most applications vary a little or sometimes completely, there are solutions for all situations.

Keep checking
Routine checking is the key to being certain that groundwater is not contaminated and that water sources are not polluted. Site licences may depend on evidence of groundwater monitoring and failure to clean up spills, especially those which are seen to cause pollution, can bring heavy financial penalties and a damaged reputation.

Interface meter
Suspended on the end of a strong, clearly marked steel measuring tape, the probe of the Geotech interface meter optically detects the boundary between groundwater and the leaked product. As it passes through the boundary the interface meter emits a change in audible tone prompting the technician to note the depth. A second change of tone marks the lower limit of the contaminant. The difference indicates thickness. Battery powered, ATEX Zone 0 certified, on a reel with sealed electronics and able to fit within very small wells of 19mm diameter, the Geotech interface meter is in daily use on sites around the world.

Removing leaked product
To remove product, technicians lower Geotech skimmers into the LNAP or DNALP layer allowing the float to stay at the top surface of the layer rise and fall with the product. With the skimmer in this position, product flows into its pipework and is drawn out with an air-operated bladder pump. By installing one or more, operators can progressively extract product at a steady rate, thus maintaining groundwater integrity at site boundaries.

Oil and water
When just the product cannot be withdrawn Geotech may advise extracting a mix of oil and water with its AP pumps (also ATEX Zone 0) and separating them with an above-ground oil and water separator.

Experienced assistance
With some twenty years’ experience of on-site applications and solutions to problems in numerous locations and with many users, Geotech readily assists and advises customers and enquirers to achieve effective monitoring and control and is able to draw on its wealth of experience to benefit customers.
More from Geotech