Problems With Free-Product Recovery

by Brian Chew on April 18, 2013

During my 33 years in the environmental field, I have been involved in a lot of sites with free product.  In the 1980’s light non-aqueous phase liquids (LNAPL) such as gasoline were removed by the following methods:

  • Bailing with a hand bailer from a well
  • Pumping with a 2 pump system (depression pump and product pump)
  • Pumping with a total fluids pump and separating above ground with an oil\water separator
  • Skimming with a belt skimmer in to a drum above ground
  • Pumping with a peristaltic pump (shallow applications)
  • Using the in-well product skimmer developed in the late 80’s

The product skimming pump is still used a great deal today, in addition to removal methods such as dual phase extraction.  The pumps have evolved from a pump that recovers product and water and expels the water back into the well before pumping the product to the surface, to a pump that only recovers product.  Is there such a thing as a pump that will only recover and pump product?  From a design point of view, yes, but from an application point of view, not really.

Why would a pump designed to recover and pump only LNAPL still pump water or not recover product?  We will assume we are using a recent model pneumatic pump with a floating intake (span of 18 inches) and a reservoir that is above the floating intake.  I have compiled a list of the items that can and will cause the pump not to work as designed:

  • No product in the well to recover
  • So little product in the well it could take months to fill the hose to ground surface(assuming the empty cycle is set just to move the recovered product out of the pump and above the check valve using a minimum amount of air)
  • The intake on the pump is installed below water or become submerged soon after installation
  • The pump intake is installed above the product
  • The intake on the pump is blocked by biomass due to lack of maintenance
  • The compressor pressure is set too low for the pump to operate or set too high and damaged the pump soon after installation
  • The compressor is on but the air valve is off, or the compressor is not on
  • The lines in the well were kinked during installation of the pump
  • The pneumatic timer in the pump is not operating due to slime and/or water in the air supply. The air dryer recommended by the pump manufacturer was not used due to cost
  • Pump check valves blocked by debris not allowing the pump to expel the product
  • The product in the well is a DNAPL and a LNAPL pump was installed to recover it

At first glance you may think some of the scenarios above are too stupid to occur.  Considering the lack of course work available at universities for this area and the lack of training given to those who are sent to install these pumps, this stuff happens all the time.  Are the manufacturers blameless in this scenario?  Not really.  Most don’t spend any more time producing procedures for installation than the consultants spend training the installers.  It is mostly common sense, right?  Or is common sense a lot less common these days?

Brian Chew
Principal Hydrogeologist

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How To Effectively Handle A Noise Nuisance

by Rand Ratterree on February 28, 2013

Occasionally we field calls from concerned citizens who are dealing with a noise nuisance. These nuisances involve irritating sounds and/or vibrations which are affecting their health via undue stress and lack of quality sleep. Typical noise nuisances are created by but not limited to:

* Parties, * Loud music, * Shouting, * Barking dogs, * Construction

The question always asked of us here at Enviro Equipment, Inc. is, “Which instrument should I use to measure the noise?” Our staff can recommend a sound level meter, but renting or purchasing an instrument frequently does not resolve their noise nuisance problem, so we usually recommend that other steps be taken first.

Initially you should identify exactly where the nuisance is originating from. Once you have established the source, you need to research the local noise laws and/or ordinances that apply. Having a witness present that can verify your complaint is helpful, and keeping a journal with nuisance times and dates is strongly recommended. With this evidence you can contact your landlord, housing authority, or homeowners association about the disturbance for a remedy of your complaint. Other possible options are to contact your local environmental health department to investigate the nuisance, seek community mediation and arbitration, or in extreme cases contact your local police.

Should you find yourself unable to identify the source of the problem then contacting an environmental noise consultant or industrial hygienist may be your best bet. These consultants possess the expertise to identify the source, research local ordinances and standards, and conduct studies utilizing the proper equipment necessary in order to present a case on your behalf.

Because the instrumentation used to record (i.e. data log) noise levels requires advanced technology and expert knowledge in deciphering data collected through an instrument’s software, environmental consultants are experts at determining what data is or isn’t important, and most importantly why; especially if the complaint becomes a legal dispute where a licensed expert’s testimony is a must. Another reason to hire a consultant to take a noise reading is the liability involved when renting or leasing a piece of equipment. For example, a commonly used instrument the CEL-633.C1/K1 retails for over $5,600. When you hire a consultant who uses their own instrument, or rents an instrument, then they would be the one assuming the risk in the event of theft or damage to the instrument.

If the noise nuisance is coming from your neighbor, we suggest knocking on their door or calling first before doing anything else. Ask if they are aware of the disturbance – do not assume they do. It will be less stressful on both parties to build a relationship based on mutual respect. Also consider the possibility that the problem may not be your neighbor, but the structure of your home, condo or apartment.

If talking to the neighbor doesn’t work, calling the police (they usually have their own noise meters) is best before resorting to a lawsuit. For more information on the legal remedies to resolve ongoing noise nuisances, go to Realestate.findlaw.com.

All content provided on this blog is for informational purposes only. The owner of this blog makes no representations as to the accuracy or completeness of any information on this site or found by following any link on this site. The owner will not be liable for any errors or omissions in this information nor for the availability of this information.  The owner will not be liable for any losses, injuries, or damages from the display or use of this information.

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