Glossary of Terms
Solid Waste Management
Farming Environmental Management
US EPA Dioxin Reassessment
Dioxin Measurement Units
Baghouses vs Precipitators
by John W. Norton, P.E., B.C.E.E.
Wastewater Engineering Experience
Few aspire to become a wastewater treatment engineer, but in the course of my professional life I became one because it is most interesting and has many wonderful challenges to be addressed. For years I have watched the expressions on people's faces when I was introduced as being in that profession.
Still, I find it most interesting, and I have spent probably 40% of my adult life working in and around municipal wastewater plants.
- "Did they hear wrong?"
- "How did it happen?"
- "Can't you get a real job?"
Wastewater Regulatory Problems
Unfortunately, there are problems with regulations on wastewater plants that are causing, or about to be causing, worsening environmental conditions. Here are some brief examples:
- New Mercury Regulations and Limits
Mercury emissions have fallen into that popular trap where the public has been so misinformed that new legislation is about to cause seriously expensive changes to the nation's wastewater plants with immeasurable improvement to the environment and public health. Keep in mind that virtually all dental fillings contain mercury. The largest source of mercury (95%) is dental offices which are not to be regulated, not even their "spit sinks." Duh.
While the required limits have yet to be set, the testing procedures give a hint about the levels being investigated:
Just to get the required sample for the $1400 lab test, it will require two laboratory people dressed in disposable Tyvex suits, a "Dirty" worker, and a "clean" worker. (Both of course, are actually very clean.) All garment edges must be taped down tight so that no human traces can contaminate the sample. (Apparently, smoking one cigarette, or being exposed to the smoke, within the last three days can cause failure of the test, some how.) The procedure goes on for pages, but in essence, after both workers are properly dressed and cleaned, the "dirty" worker grabs the sample and pours it into special containers held by the "clean" worker just to get a pure sample.
Only specially certified labs will be able to do the test on the sample. The environment will not know the difference.
- Sludge Management Rules
Sludge is frequently used ("disposed of") on farm land after being carefully monitored for its contents. The monitoring is to make sure that unhealthy levels of metals and salts do not build up on any one section of land. Every land disposal site for sludge is now recorded by the state EPA along with the amounts of each type of sludge that has ever been deposited and the laboratory analysis of the sludge deposited.
Sludge is very good for the farm land. I have personally witnessed many trials and full scale uses of municipal sludge over the years.
Crops that have the benefit of the sludge are astonishingly more healthy looking in a way that is visible to anyone. The crops grown on soil with sludge applied are greener and fuller and far more drought resistant than crops without sludge (being raised only 12 inches away.) I have seen demonstrations where strips of the same field were treated with and without sludge, side by side. It is literally possible to write your name in a field with a sludge spreader and see the name reflected later in the healthier crops where the sludge tracks were made. It is not just the fertilizer value that makes the difference, it seems to be the organics that hold moisture, or perhaps the trace metals. University studies continue.
Contrary to often common belief, sludge being put on a farm field has almost no odor. The little smell it has is very "earthy," not ammonia like, but rumors abound. Here locally I have heard people say many times that "They must be putting sludge on that airport property. It just smells awful!" They have always been wrong. I know that the airport has not had sludge in at least the last 40 years. What they are smelling is Urea, a cheap, factory produced, high ammonia fertilizer.
One of the nearby townships has actually banned the application of wastewater sludge because of this same misunderstanding in their area. What an environmental tragedy; good sludge simply does not stink.
- Sludge Transportation Rules
Now, there are laws being suggested that will treat sludge as a hazardous waste; if "any" is dropped on the road on the way to Farmer Brown's, the "Hazmat team" will need to be called. Why? How much is "any"?
Some cities burn sludge in special incinerators. This is a waste of a good organic resource. Sludge burning does not release enough energy to even keep the fire going; most such operations require additional gas fuel (energy) just to keep the fire going in a clean manner.
Such new sludge transportation regulations will push more cities into the sludge burning operation with net negative impact on the environment. And what is the more common choice for sludge disposal, burial in landfills!
- Metals Rules
Metals dissolved in water are being regulated in ever more strange ways. At the moment, for example, copper limits are allowed to be higher in the drinking water than they are in the wastewater being put back into the stream.
Many metals limits are this way. Is it conceivable that this is necessary in order to preserve the health of the stream or its fish and wildlife?
If the environment is truly to be preserved, the rules and regulations have got to make good sense. Good science has to be used to determine the limits that are needed. If the regulations require more than nature requires, then the rules are the result of some other motivation than that of preserving nature.