Скачать или смотреть PE Exam Practice Problem #98: Water Resources/Environmental | NOAEL, DWEL, Ref Dose, Intake Rates

Welcome to SolvedIn6: Free practice problems for the Professional Engineering Exam! Each question is styled after those created by the NCEES, and is usually solved in under 6 minutes, which is the average time you will have to solve each question on the Professional Engineering Exam.

Today’s Problem:
This is a problem which could appear in some form on either the Water Resources or Environmental exam. We are given a maximum contaminant level in drinking water for arsenic and an uncertainty factor. We are asked to find the approximate daily intake level that would "not be expected to result in adverse health effects". This part is in quotes because it should help you to recognize that we are looking for the term NOAEL. This will be one of two equations to use in this problem. The other will involve the reference dose and DWEL, or drinking water equivalent level, since this contaminant is being introduced via drinking water.
Solving for these two equations will allow you to find the NOAEL. In the environmental reference manual, there is an Intake Rates table that will give you the required body weight and drinking water consumed per day. If this is on the civil exam, these would likely need to be provided since the equations in the manual exclude them for some reason.

If you would like more practice problems, please check out the rest of the playlist which this video is part of. Please note that newer versions of the reference manual may have been released since this video was recorded. The search terms are usually still correct, but the page numbers listed in the video will be different.