Department of Civil and Environmental Engineering

The University of Connecticut - Storrs

Questions and Answers Bulletin for

CE-294 and CE-320

Environmental Systems Analysis

Spring 1997




Please submit your questions through e-mail and I will post both questions and answers in this bulletin board. The board will be updated throughout the semester. Keep checking.

***************************************************************

Questions and Answers for Assignment #1

***************************************************************

Question #1. I can not access the assignment. Can you help me?

Answer #1. The web page is up. I do not know why you could not access it. It is possible that you did not capitalize the first letter of Nikolaidis.html

You can find the assignment at

http://www.eng2.uconn.edu/~nikos/ce294ass1.html

Let me know if you have problems.

***************************************************************

Question #2. With solving the homework assigment of course CE-320, I have two questions.

1. Where I can find the world population data (for problem 2) ?

2. Could you teach us several widely used statistical criteria such as Chi-square test, Paired t-test and Linear least-square regression as introduced in example 1.3 of textbook ?

Answer #2.

1. You can find the population data in the library, probably under world population statistics or atlases.

2. You can follow the procedure outlined in the book, or you can use EXCEL to compute these statistics for your data. If you have trouble with interpreting the results you should come and see me.

***************************************************************

Question #3. How should we compare the observed with the modeled data?

Answer #3. Use the same statistics as in the book: chi^2, t-test, and r^2. Let me know if you have any questions.

***************************************************************
Question #4.

1. Should it be assumed that Lake Superior is marine water?

2. Is it okay to assume that chromate is both chromium(hex) and chromium(tri)?

3. Is the water quality criteria applicable to ground water or is the human health criteria(which includes drinking water MCL) just applicable to groundwater?

4. Are there any criteria for rainwater or should I just assume that all the criteria applies to rain water also?

Answer #4.

1. I believe that Lake Superior is freshwater.

2. Chromate is hexavalent only.

3. I believe that the various State Ground Water Protection Criteria involve both.

4. No. Use the Water Quality Criteria.

***************************************************************
Questions and Answers for Assignment #2

***************************************************************

Question #1. Do we need to get the maximum solubility

>for phenol (if so what type) and chromium? If not than what would Co equal to

>in the equation C = Co + ( C background - Co) * erf(zeta).

Answer #1. No need to find solubilities.

***************************************************************

Question #2. The question, (C-Co)/(Cb-Co)=erf(X), was used to solve the problem. Co=1.5 mg/L(Initial Conc.) Cb= 0 mg/L (Since no Phenol in clay layer in the begining) C=0.01 mg/L ( When c > 0.01 mg/L, the Phenol Conc., in the G.W., it is the time that the clay lechate will begin to contaminate the G.W.) Is the solving philosophy correct ? If not, please give a direction.

Answer #2. Cb = 0.01. The contamination begins when C>0.01. You are on the right track.

***************************************************************

Question #3. Would it be possible to have homework assignments due on Friday morning so that we could have a few minutes to ask questions during class on Thursday? This might minimize repetition of the same question and stimulate some discussion.

Answer #3. This is a great idea. I'll change the due date of the assignments. Thank you.

**************************************************************
Questions and Answers for Assignment #5

**************************************************************

Question #1. Problem 1. In calculating the vertical dispersion coefficient, are we to use the same value as the mean depth (D) for the depth of the river (z)? If so then it would be zero.

Answer #1. z takes values from 0 to 10 m. So you can find the vertical distribution

of dispersion with depth. You can use increaments of 1 m. Plot Ez vs Z.

**************************************************************



Instructor: Dr. Nikolaos P. Nikolaidis

Office: FLC Rm 318

e-mail: nikos@eng2.uconn.edu

Homepage: http://www.eng2.uconn.edu/cee/bio/Nikolaidis.html

Office Hours: Th 11:00 - 1:00 PM

Lecture: Th 8:00 - 11:00 AM, STORRS HALL 311

TA: Peg Engwall


e-mail: nikos@eng2.uconn.edu