AboutDavid L. Russell, PE Expertise I`m a Chemical,Civil and Environmental Engineer and have a number of projects in all phases of the environment.
I have worked in the chemical industry and am active in professional societies, and am currently on an industrial wastes committee for the Water Environment Federation, and have taught courses in remediation in the US and abroad.
I have written one book on Remediation of petroleum Contaminated Sites, and have a second book on PRACTICAL WASTEWATER TREATMENT to be published by John Wiley in September, 2006. I've also written over 30 articles on various elements of environmental problems and cleanup. Most Recently, I have addressed a NATO Scientific and Techical Conference on Ecoterrorism, and have worked with the same group on remediation of sites contaminated with Chemical Warfare Agent materials and othe materials as well. . I can answer q`s about Chemical and Environmental Engineering, land development, air pollution, water pollution, soil and water cleanup, combustion, international environmental problems, industrial processes chemical processes. Civil and Environmental and Chemical Engineering. Overall, I have over 35 years of experience in this area. Note: I do not answer homework questions
Experience I love work in the third world and developing areas
because it is challenging and one can get a sense of accomplishment.
Question Hello, I read your information about this subject and found it helpful. However, I should like to check out something. We have "biological" or "non biological wash powders. Is there somewhere information on specific chemicals and their effects on septic tanks? For example, Phosphonates - are these harmful to the tank.(I'm very happy to do the reading if you could just point me in the right direction. Good wishes. Mike
Answer My answer may seem a bit convoluted, but bear with me.
Most bacteria, of the type that are in your septic tank, contained carbon nitrogen and phosphorus in a specific ratio of approximately 100:20:1. The purpose of the septic tank is to degrade whatever is put into it. It is a type of anaerobic digester. Anaerobic digesters are reasonably good treatment systems, but they are very very slow.
There are a few good databases on organic chemistry and biological the composition pathways -- but I would suspect that they are far beyond your interest level. If you have questions about a specific compound or a specific product I suggest that you go on the Web and obtain the Material Safety Data Sheet for the Item of interest. On the material safety data sheet you will find an indication of the toxicity of the compound. It may not be the best or totally relevant information, but it is by far the most available.
Most of the "biological" washing powders tend to have three things in common. The first is that they are pH balanced -- have lower our political levels and are not quite as caustic as many of the stronger commercial compounds. The second thing is that they often have biological enzymes which are designed to be natural substances that help break down grease so that it can be washed off the dishes. A third thing is the fact that they will often have much lower phosphorus levels or will substitute phosphorus for silicates. The reason for this is that a little phosphorus goes along way -- and you can see from the biological ratios above that 1 pound of phosphorus will require 20 pounds of nitrogen and over 100 pounds of carbon in order to absorb it into a mass of biological cells. If you don't have the 100 pounds of biological cells -- and most septic tanks probably have a few tens of pounds of cellular material in them -- the balance of the phosphorus is washed through and exits the septic tank and goes into the leaching field. From the leaching field of phosphorus may or may not be absorbed in the soil and it may wind up contaminating groundwater.
If you have been following the news lately, there has been a bit of smuggling going on in either the state of Washington or Oregon with regard to commercial washing powders. The residents of that area have hard water -- higher levels of Calcium and Magnesium -- which interact with many of the compounds in the "low phosphorus" detergents. The reaction forms a soap film which is the dickens to get off once it's dried. As a consequence, and in defiance of State Law, there is a smuggling operation going on with people who are tired of not having "clean" table wear.
