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tal engineering field for approximately 15 years, the last 10 of which have been in the operations
of wastewater treatment plants and water treatment systems.
I am presently employed by Hydro Managnment Services, an environmental engineering company in
Winston-Salem that does contract operations for wat^r and wastewater treatment plants. We presently
operate 14 plants around, throughout the state of North Carolina.
Prior to coming with this company, I worked with the City of Winston-Salem. I ran the city's
plant for five years as the largest wastewater treatment plant in the state of North Carolina, and
one of the largest ones in the south.
Prior to that I worked with a consulting firm out of Nashville, TN. We did primarily indus-
trial wastewater treatment. We worked all over the world. The last project I had with them was
with the World Health Organization, designing a wastewater treatment plant for (not clear).
With that, get back to the issue at hand here. There's, people get together, congregate, one
of the things we have to address as engineers is sewage treatment, provide water, provide sewage
treatment. The questions comes up. There is several methods of providing sewage treatment. One is
to let the wastewater percolate through the ground. It comes through a septic tank. The septic
tanks is a square box, if you will, so designed to retain any solid material, paper, rubber, plastic
type material and grease going out into the leech field.
There is biological activity in these tanks. They, by their name "septic" they are a type of
treatment that is anaerobic or occurs in the absence of oxygen. It's an interesting point you made,
generally you see septic tanks below the ground, because being anaerobic or septic, they give off
offensive odors. This type of treatment you generally see below the ground in the event there are
any leaks in the tanks, any escaping gases or odors, generally they are blanketed by the earth
around it.
That's one type of treatment. It's probably the second oldest type of treatment. The oldest
type is just direct discharge into the ground.
As we became more, areas became more populated, we looked at other ways to treat in smaller
land areas. One of the disadvantages of septic tanks is that it requires large land areas. There
is drain fields. One of the things that you generally find with septic tanks is that they will
fail. Sooner or later, they do fail. You have got soil capacity being reached, you've got ront
intrusions. You've got all sorts of things that will cause them to fail. Generally, it has been my
experience that septic tanks originally fail because they are not properly maintained by the owner.
Generally these things are put in and forgotten about until such point in time that sewage bubbles
on top of the ground.
My opinion is that the most common reason that they fail is that the tanks are not properly
maintained. That is, they are not pumped out frequently enough. Oil and grease builds up in these
tanks, a scum layer builds up that will eventually works it way out into the drain field and float
the field.
Another type of treatment is a sewage treatment plant. I would like to digress and talk about
a package treatment plant. A sewage treatment plant is a combination of units that generally we're
talking about biological treatment, some of them are aerated units, some of them are stone media
with the water that is sprayed over them. There's any number of sewage treatment plants. What we
talk about when we say package treatment plant is nothing but a modular plant that is shop welded
and put together and brought to the site as one unit. That same type plant with the same type of
equipment and same size units could just as easily be fabricated on the site. A package plant, we
generally think of those as 3/16 or 1/4" steel plate and tanks, simply steel tankage. They're
manufactured by any number of manufacturers. There's nothing magical about the word package other
.,._. than it's pre -assembled and brought to the site as a unit that's designed to meet that flo••!.
Generally the state requires when we put in one of these type treatment systems, they make a
number of requirements, and they enforce these requirements through the NPDS permit, the National
Pollution Discharge Elimination System Permit. This permit regulates the quality and the quantity
of water that may be discharged from one of these plants. It also establishes the monitoring
frequency, who will do the analyses. It says that a certified laboratory must do the analyses, a
certified operator, a qualified operator must operate the plant. It also states the frequency that
he must attend to the plant, what tests he must take on a daily basis, a weekly basis, monthly
basis. All this is colated and put into a report that is sent monthly to the State regulatory
agencies.
There is very severe penalties for failure to comply with these, not the least of which is
fines that can range from $5 to $10 thousand dollars per day, and each day is a separate violation,
for failure to comply with the regulations established.
The systems have been in existence and in use for, we've got treatment plants in the United
States that have been in service for, the City of Winston-Salem's treatment plant. We have package
plants and we have large plant that is constructed on site. The City has had a plant for the last
four years. The existing plant now has been in service for nearly 30 years. We have package plants
in Forsyth County that have been in the ground 25 years. I presently, as I mentioned earlier, our
company operates 14 plants across North Carolina. We treat, we have plants that treat up to 4
million gallons a day. We have small systems that treat 10,000 gallons a day.
We are presently operating four plants. Four of these, if you will, package treatment plants,
that are above the water intake of the City of Winston-Salem. We discharge into the Yadkin River.
These four plants are,one of them is as clos^ as a mile upstream from the City of Winston-Salem's