CWACS Pretreatment Newsletter: Recent Comments

Comment on EPA Proposes Alternate Oil and Grease Method for Comment

Curt at CWACS — Wed, 14 Dec 2011 16:21:23 GMT

Comment to EPA: For SIUs that have to monitor oil and grease for a Categorical Standard, shouldn't comparison data be included with Method 1664 for these specific wastewaters? If this is an alternate method under Part 136, this seems like a requirement.

Comment on Interesting Question: NSCIU and No Discharge

Pam Kirklin — Tue, 30 Aug 2011 11:08:39 GMT

Nice summary of ways to deal with zero or no discharge users. Thank you.

Comment on Cadmium+Selenium Nanopollutants Breakdown in Soils

Sandra — Wed, 20 Jul 2011 15:25:19 GMT

What are quantum dots used for?

From Wikipedia (Seems to be a pretty good definition!).

Curt

A quantum dot is a portion of matter (e.g. semiconductor) whose excitons are confined in all three spatial dimensions. Consequently, such materials have electronic properties intermediate between those of bulk semiconductors and those of discrete molecules.^{[1] [2] [3]} They were discovered at the beginning of the 1980s by Alexei Ekimov ^[4] in a glass matrix and by Louis E. Brus in colloidal solutions. The term "quantum dot" was coined by Mark Reed.

Researchers have studied quantum dots in transistors, solar cells, LEDs, and diode lasers. They have also investigated quantum dots as agents for medical imaging and hope to use them as qubits.

Stated simply, quantum dots are semiconductors whose electronic characteristics are closely related to the size and shape of the individual crystal. Generally, the smaller the size of the crystal, the larger the band gap, the greater the difference in energy between the highest valence band and the lowest conduction band becomes, therefore more energy is needed to excite the dot, and concurrently, more energy is released when the crystal returns to its resting state. For example, in fluorescent dye applications, this equates to higher frequencies of light emitted after excitation of the dot as the crystal size grows smaller, resulting in a color shift from red to blue in the light emitted. In addition to such tuning, a main advantage with quantum dots is that, because of the high level of control possible over the size of the crystals produced, it is possible to have very precise control over the conductive properties of the material.^[5] Quantum dots of different sizes can be assembled into a gradient multi-layer nanofilm.

Curt McCormick

CWACS

(720) 320-1945

www.POTW.com

Curt@POTW.com

Comment on H.R. 2018: Bill Passes U.S. House That Would Gut National Consistency in Water Pollution Protection

Eric Swope — Thu, 14 Jul 2011 17:13:23 GMT

It sounds like some special interest groups have very specific lists they are trying to push through and are very busy in the back rooms. Also sounds like they have some very willing ears they are talking into.

Comment on EPA to Declare Protein As New Life Form

Chris S — Fri, 28 Jan 2011 16:45:40 GMT

Maybe they should just get prions an emergency listing under the Endangered Species Act.

Comment on Gary, IN: Wastewater Treatment Operator and Managers Charged with Conspiracy and Violating the CWA

Chris S — Wed, 15 Dec 2010 23:30:26 GMT

What is with these 10 years contracts in the WW industry?

Comment on Two Interesting Articles - Florida Sues EPA and Antibiotics in Wastewater

Vivian Matkivich — Thu, 09 Dec 2010 12:41:41 GMT

The lawsuit may cure EPA and other agencies of less than thorough review of costs of a regulation, as required by the the Regulatory Flexibility Act. it certainly bears watching. As for antibiotics, many understand the issue with antiobiotics and other prescription drugs. I am glad the article clarifies that most of the problem is actaully coming from agricultural operations.

Comment on ADA Position on Categorical Standards

G Wilson — Thu, 18 Nov 2010 16:50:51 GMT

Here are a few comments on the ADA’s principles:

1. The dentist must be compliant with the requirements set forth by the POTW’s local limits - only requiring installation of said equipment may or may not meet these limits.
2. What if, down the road, the existing laws do not meet the treatment levels required by technically based local limits? The POTW would have its hands tied when trying to meet any limits set for its effluent with respect to mercury.
5. If any other industry is discharging a pollutant in excess of their permit, for any reason, they are deemed in violation of their permit immediately. Why shouldn’t the dentists be as well? Additionally, what is a reasonable amount of time? (Sounds like an argument only a lawyer could love.)
6. Every other categorical industry is required to have an individual permit. Why should the dentists be handled differently?
7. If a POTW is discharging mercury (or any other pollutant) they must have the ability to control all sources of that pollutant. Exempting one class of dischargers is creating a “favored group". That is wrong and could harm the POTW and the environment.
8. If the EPA adopts the exemption of testing for the dentists, they are again creating a “favored group".

The ADA must feel that the profits for the Dentists are more sacred than the profits for all other industries.

One other thought:
• In Massachusetts, currently, the state issues permits and collects the fees for such permits. I hope this will continue and the local POTWs will not have to issue a duplicate permit.
• This will in effect, put all of the burden of proof on the local POTW. I can just hear it now: “If the system does not work, chase to the manufacturer, not me – the Dentist.”

Comment on ADA Position on Categorical Standards

Kenney Farmer — Wed, 17 Nov 2010 18:57:22 GMT

In my position as pretreatment coordinator for our town, I sent letters to the 9 local dentists, informing them of the possible EPA ruling on amalgam separators. I found that out of the 9, two had separators in place and one was investigating the market prior to purchase. Later I was speaking in person to my own dentist about the issue, he stated, the ADA would do the right thing and there would be very little to worry about. He seems to have complete trust in their way of thinking.

Comment on ADA Position on Categorical Standards

Eric Rajaniemi — Wed, 17 Nov 2010 18:15:40 GMT

I don't see how they think that #9 can exist with #7. Stricter local limit would more than likely be in the form of a stricter numerical concentration which principle #7 says it does not think should happen. EPA allows for state and local governments to enforce stricter controls than the federal limits, we simply can't be less strict than they are.