Field Trip - Northern Guam Lens Aquifer Jun 2014 | Page 26

From Sustainable Yield to
Sustainable Management
➤ 1982 Northern Guam Lens Study

“The rate of production that can be sustained without

unacceptably degrading water quality.”
So…

What is acceptable quality?

Who decides?
How?

➤ USEPA secondary standard: 250 mg/l chloride

1.3% seawater

Increasing salinity is a
natural consequence of
increasing extraction.
Salinity

➤ NGLS quality target: 150 mg/l chloride

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Drinking Water
Salinity vs. Production

➤ World Health Organization guideline: 600 mg/l chloride

~3% seawater
Sustainable Yield estimates were based on percentages of estimated
recharge. Sustainable Management considers aquifer response to
extraction and adaptive approaches to production.

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Production

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