Drainage from a former pesticide manufacturing site enters Bear River at river kilometer 240. The drainage contains DDT, and the concentration of DDT after complete mixing is 5 µg/L. The town of Bear Valley, adult population 15,000, uses the river at river kilometer 40 for its water supply with only chlorination. The drainage has occurred for 30 years. The river velocity is 5 cm/s. Assume the half-life of DDT is 70 days (a) The concentration of DDT in the town's drinking water is mostly nearly (A) 1.2 µg/L (B) 2.3 μg/L (C) 3.2 μg/L (D) 3.9 µg/L (b) With 2 L/day water consumption, adult body mass of 70 kg, and life expectancy of 70 years, the lifetime chronic daily intake of DDT for an adult living in Bear Valley is most nearly (A) 4 x 10³ mg/kg-day (B) 8 x 10 mg/kg-day (C) 6 x 10³ mg/kg-day (D) 2 x 10² mg/kg-day (c) Assume a slope factor of 0.34 (mg/kg-day)-¹ for DDT. The number of excess lifetime cancers that can be expected in the adult population of Bear Valley is most nearly (A) 0.05 (B) 0.2 (C) 4 (D) 12

Drainage from a former pesticide manufacturing site enters Bear River at river kilometer 240. The drainage contains DDT, and the concentration of DDT after complete mixing is 5 µg/L. The town of Bear Valley, adult population 15,000, uses the river at river kilometer 40 for its water supply with only chlorination. The drainage has occurred for 30 years. The river velocity is 5 cm/s. Assume the half-life of DDT is 70 days (a) The concentration of DDT in the town's drinking water is mostly nearly (A) 1.2 µg/L (B) 2.3 μg/L (C) 3.2 μg/L (D) 3.9 µg/L (b) With 2 L/day water consumption, adult body mass of 70 kg, and life expectancy of 70 years, the lifetime chronic daily intake of DDT for an adult living in Bear Valley is most nearly (A) 4 x 10³ mg/kg-day (B) 8 x 10 mg/kg-day (C) 6 x 10³ mg/kg-day (D) 2 x 10² mg/kg-day (c) Assume a slope factor of 0.34 (mg/kg-day)-¹ for DDT. The number of excess lifetime cancers that can be expected in the adult population of Bear Valley is most nearly (A) 0.05 (B) 0.2 (C) 4 (D) 12

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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Concept explainers

Landfills

The landfill is a site used for the disposal of waste materials. The landfill is a solid waste facility that is often known as a dumping ground. The image below shows a landfill site in Hawaii. Landfilling is the most ancient and common method used for the disposal of waste. For the landfill, a deep trench is constructed in an isolated place away from the city. The trench for landfills is designed properly after analyzing the total population and the waste generation per capita. The waste is dumped into the trench and after every layer of waste, a layer of soil is spread on the top of it.

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Drainage from a former pesticide manufacturing site enters Bear River at river kilometer 240.
The drainage contains DDT, and the concentration of DDT after complete mixing is 5 µg/L. The
town of Bear Valley, adult population 15,000, uses the river at river kilometer 40 for its water
supply with only chlorination. The drainage has occurred for 30 years. The river velocity is 5
cm/s. Assume the half-life of DDT is 70 days
(a) The concentration of DDT in the town's drinking water is mostly nearly
(A) 1.2 µg/L
(B) 2.3 µg/L
(C) 3.2 µg/L
(D) 3.9 μg/L
(b) With 2 L/day water consumption, adult body mass of 70 kg, and life expectancy of 70
years, the lifetime chronic daily intake of DDT for an adult living in Bear Valley is most nearly
(A) 4 x 10³ mg/kg-day
(B) 8 x 10 mg/kg-day
(C) 6 x 10³ mg/kg-day
(D) 2 x 10² mg/kg-day
(c) Assume a slope factor of 0.34 (mg/kg-day)-¹ for DDT. The number of excess lifetime
cancers that can be expected in the adult population of Bear Valley is most nearly
(A) 0.05
(B) 0.2
(C) 4
(D) 12

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