Water with 1.0 mg/L methylene chloride + 0.01 mg/L tetrachloroethylene), 70 kg adult drinks 2L/day for...
Water with 1.0 mg/L methylene chloride + 0.01 mg/L tetrachloroethylene), 70 kg adult drinks 2L/day for 30 years. What is hazard index?
RfD = 0.060 for methylene chloride, RfD = 0.010 for tetrachloride
| 1 |
0.512 |
|
| 2 |
0.029 |
|
| 3 |
0.483 |
|
| 4 |
0.00029 |
q2)
A test bottle (Blank) containing just seeded dilution water has its DO level drop by 1.1 mg/L in a five-day test. A 300-mL BOD bottle filled with 30 mL of wastewater and the rest seeded dilution water (this is a ratio of 30:300 or 1:10) experiences a drop of 6.9 mg/L in a five-day test. What is the BOD5 of the original wastewater?
| 1 |
69 |
|
| 2 |
59 |
|
| 3 |
49 |
|
| 4 |
39 |
Homework Answers
Add Answer to:
Water with 1.0 mg/L methylene chloride + 0.01 mg/L
tetrachloroethylene), 70 kg adult drinks 2L/day for...
ENV3006C HW#4 The following data provided to you. Calculate the BODS of the WW sample (mg/L)...
ENV3006C HW#4 The following data provided to you. Calculate the BODS of the WW sample (mg/L) are Seeded wastewater (WW): Initial DO 8.2 mg/L; Volume of wastewater Final DO (after 5 days) 2.5 mg/L Total volume in BOD bottle = 300 mL 5 mL Seeded dilution water: Final DO (after 5 days) 7.3 mg/L Initial DO 8.3 mg/L; Volume of seeded dilution water 300 mL
Two samples are brought to the laboratory for the BOD test. Please calculate BOD5 for both,...
Two samples are brought to the laboratory for the BOD test. Please calculate BOD5 for both, using laboratory DO data. a. For sample A, seeded BOD test was performed. The initial DO concentration in the BOD bottle, which was filled with 2 mL of sample and 298 mL of seeded dilution water, was 8.9 mg/L just after preparation. After an incubation period of five days, the final DO concentration was reported as 1.8 mg/L. Meanwhile, DO concentration in the seed...
While interning at a wastewater treatment plant, you conduct a seeded BOD5 test of the lant's...
While interning at a wastewater treatment plant, you conduct a seeded BOD5 test of the lant's effluent. For the experimental bottle, you insert 30 mL of test sample into the 300-mL ottle and fill the rest with seeded dilution water. You fill a blank bottle with seeded dilution ater. You measure the following dissolved oxygen (DO) concentrations at the start and end f the 5-day test: Bottle Initial DO (mg/L) Final DO (mg/L) Experimental 8.1 4.6 Blank 7.8 6.7 hat...
A 70-kg individual drinks 2 L/day of water containing 0.015 mg/L of tetrachloroethylene for 20 years....
A 70-kg individual drinks 2 L/day of water containing 0.015 mg/L of tetrachloroethylene for 20 years. (a) Find the hazard quotient for this exposure. (b) Find the cancer risk. (c) If the individual drinks this water for 30 years instead of just 20, recomputed the hazard quotient and the cancer risk. A man works in an Aluminum smelter for 10 years. The drinking water in the smelter contains 0.015 mg/L arsenic and 0.80 mg/L methylene chloride. His only exposure to...
De constant kiday"). 8. A standard BOD test is run using seeded dilution water. In one...
De constant kiday"). 8. A standard BOD test is run using seeded dilution water. In one bottle, the water sample is mixed with seeded dilution water giving a dilution of 1:30. Another bottle, the blank, contains just seeded dilution water. Both bottles begin the test with DO at the saturation value of 9.2 mg/L. After five days, the bottle containing waste has DO equal to 2.5 mg/L while that containing just seeded dilution water has DO equal to 8 mg/L....
3. (6 pts) Raw wastewater with initial BOD5 = 265 mg/L is treated in Wastewater Treatment...
3. (6 pts) Raw wastewater with initial BOD5 = 265 mg/L is treated in Wastewater Treatment Plant (WWTP), which can remove 65% of initial BOD. Students were asked to run BODs tests on the treated wastewater AFTER treatment. They used standard 300 ml bottle a. Find the volume of treated wastewater that should be put in the bottle to make sure that DO after 5 days will be at least 2mg/L (assume initial DO = 9.2 mg/L; and the bottle...
2. To determine the BOD in an industrial wastewater sample, a seeded BOD analysis was conducted;...
2. To determine the BOD in an industrial wastewater sample, a seeded BOD analysis was conducted; data are summarized in the table below. Ten mL of wastewater was added per 300 mL bottle to determine the dissolved oxygen demand of the aged, settled wastewater seed (test A). The seeded test bottles (test B) contained 2.5 mL of industrial wastewater and 1.2 mL of seed wastewater a) What is the five-day BOD in this industrial wastewater? What is the k-value using...
Given the following BOD data: Time (days) Diluted sample DO (mg/l). 7.95 3.75 3.45 2.75 2.15...
Given the following BOD data: Time (days) Diluted sample DO (mg/l). 7.95 3.75 3.45 2.75 2.15 1.80 Blank seeded sample Do (mg/l) 8.15 8.1 8.05 8.0 7.95 7.9 Find the BOD at 5 days knowing that the diluted sample was diluted 100 times, i.e., P=1/100-volume wastewater/[volume of wastewater+dilution water (300 ml)).
The drinking water standard for tetrachloroethylene is 0.005 mg/L. The potency factor for tetrachloroethylene is 5.1*10^-2(mg/kg-day)-1....
The drinking water standard for tetrachloroethylene is 0.005 mg/L. The potency factor for tetrachloroethylene is 5.1*10^-2(mg/kg-day)-1. What lifetime risk would this pose? Assume 30 year exposure for 350 days per year
4. A 20 mL wastewater sample was mixed with 280 mL deionized (DI) water in a...
4. A 20 mL wastewater sample was mixed with 280 mL deionized (DI) water in a standard BOD bottle. The 5- day BOD test provided an initial dissolved oxygen concentration (DO intial) = 9 mg/L and a final dissolved oxygen concentration (DO final) = 3.5 mg/L. The BOD experiment was carried out at 20°C and the BOD rate constant at 20°C is 0.22/day. a. Find the dilution factor (P) and BODs value at 20°CY b. Find the ultimate BOD of...
ENV3006C HW#4 The following data provided to you. Calculate the BODS of the WW sample (mg/L) are Seeded wastewater (WW): Initial DO 8.2 mg/L; Volume of wastewater Final DO (after 5 days) 2.5 mg/L Total volume in BOD bottle = 300 mL 5 mL Seeded dilution water: Final DO (after 5 days) 7.3 mg/L Initial DO 8.3 mg/L; Volume of seeded dilution water 300 mL
While interning at a wastewater treatment plant, you conduct a seeded BOD5 test of the lant's effluent. For the experimental bottle, you insert 30 mL of test sample into the 300-mL ottle and fill the rest with seeded dilution water. You fill a blank bottle with seeded dilution ater. You measure the following dissolved oxygen (DO) concentrations at the start and end f the 5-day test: Bottle Initial DO (mg/L) Final DO (mg/L) Experimental 8.1 4.6 Blank 7.8 6.7 hat...
A 70-kg individual drinks 2 L/day of water containing 0.015 mg/L of tetrachloroethylene for 20 years. (a) Find the hazard quotient for this exposure. (b) Find the cancer risk. (c) If the individual drinks this water for 30 years instead of just 20, recomputed the hazard quotient and the cancer risk. A man works in an Aluminum smelter for 10 years. The drinking water in the smelter contains 0.015 mg/L arsenic and 0.80 mg/L methylene chloride. His only exposure to...
De constant kiday"). 8. A standard BOD test is run using seeded dilution water. In one bottle, the water sample is mixed with seeded dilution water giving a dilution of 1:30. Another bottle, the blank, contains just seeded dilution water. Both bottles begin the test with DO at the saturation value of 9.2 mg/L. After five days, the bottle containing waste has DO equal to 2.5 mg/L while that containing just seeded dilution water has DO equal to 8 mg/L....
3. (6 pts) Raw wastewater with initial BOD5 = 265 mg/L is treated in Wastewater Treatment Plant (WWTP), which can remove 65% of initial BOD. Students were asked to run BODs tests on the treated wastewater AFTER treatment. They used standard 300 ml bottle a. Find the volume of treated wastewater that should be put in the bottle to make sure that DO after 5 days will be at least 2mg/L (assume initial DO = 9.2 mg/L; and the bottle...
2. To determine the BOD in an industrial wastewater sample, a seeded BOD analysis was conducted; data are summarized in the table below. Ten mL of wastewater was added per 300 mL bottle to determine the dissolved oxygen demand of the aged, settled wastewater seed (test A). The seeded test bottles (test B) contained 2.5 mL of industrial wastewater and 1.2 mL of seed wastewater a) What is the five-day BOD in this industrial wastewater? What is the k-value using...
Given the following BOD data: Time (days) Diluted sample DO (mg/l). 7.95 3.75 3.45 2.75 2.15 1.80 Blank seeded sample Do (mg/l) 8.15 8.1 8.05 8.0 7.95 7.9 Find the BOD at 5 days knowing that the diluted sample was diluted 100 times, i.e., P=1/100-volume wastewater/[volume of wastewater+dilution water (300 ml)).
4. A 20 mL wastewater sample was mixed with 280 mL deionized (DI) water in a standard BOD bottle. The 5- day BOD test provided an initial dissolved oxygen concentration (DO intial) = 9 mg/L and a final dissolved oxygen concentration (DO final) = 3.5 mg/L. The BOD experiment was carried out at 20°C and the BOD rate constant at 20°C is 0.22/day. a. Find the dilution factor (P) and BODs value at 20°CY b. Find the ultimate BOD of...
Most questions answered within 3 hours.
-
The pH of a sample of water from a river is 5.0. A
sample of effluent from...
asked 9 minutes ago -
At the beginning of the period, the Fabricating Department
budgeted direct labor of $136,500 and equipment...
asked 37 minutes ago -
Please answer all
____ 28. Rent control is usually
justified on the grounds that it protects...
asked 36 minutes ago -
PARTS A-D HAVE BEEN ANSWERED. WAS TOLD TO REPOST. ONLY ANSWER
PARTS E and F.
A...
asked 54 minutes ago -
2) You are given the task of finding a representation for a
circle in a drawing...
asked 2 hours ago -
STUDY QUESTION: Does use of diet drug fen-phen
(fenfluramine-phentermine) cause valvular heart disease?
HINT: Valvular heart...
asked 1 hour ago -
1. An object weighing 40 N rests on a surface. The coefficient
of friction is 0.35....
asked 3 hours ago -
Investor company owns 35% of investee company voting stock and
accounts for the investment under the...
asked 4 hours ago -
The number of major faults on a randomly chosen 1 km stretch of
highway has a...
asked 4 hours ago -
Consider the competitive environment of Starbuck's, Progressive
Insurance, a manufacturing firm with low turnover, or a...
asked 5 hours ago -
3. Gains from trade
Consider two neighbouring island countries called Euphoria and
Contente. They each have...
asked 7 hours ago -
A business executive has the option to invest money in two
plans: Plan A guarantees that...
asked 9 hours ago