A lake contains 2x105 m3 of water and is fed by a river discharging 9x104 m3/yr. Evaporation across the lake surface removes 27.4 m3/day on average and the flow leaving the lake is about 8x104 m3/yr. The upstream river is polluted with a chemical at a concentration of 6 mg/L (assume the chemical does not evaporate with the water). Inside the lake, the chemical decays at a rate of 0.12 yr-1. Suddenly, the source of contamination to the River is removed. Determine what the concentration in the lake would be after one year.

A lake contains 2x105 m3 of water and is fed by a river discharging 9x104 m3/yr. Evaporation across the lake surface removes 27.4 m3/day on average and the flow leaving the lake is about 8x104 m3/yr. The upstream river is polluted with a chemical at a concentration of 6 mg/L (assume the chemical does not evaporate with the water). Inside the lake, the chemical decays at a rate of 0.12 yr-1. Suddenly, the source of contamination to the River is removed. Determine what the concentration in the lake would be after one year.

Sustainable Energy

2nd Edition

ISBN:9781337551663

Author:DUNLAP, Richard A.

Publisher:DUNLAP, Richard A.

Chapter14: Ocean Thermal Energy Conversion And Ocean Salinity Gradient Energy

Section: Chapter Questions

Problem 20P

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