Question

A confided aquifer has a piezometric height of 30 feet before being pumped. The well is then pumped at 250 gallons/day for a very long time and results in a drawdown of 10 feet at the well. If the transmissivity in the aquifer is 10.0 ft2/day and the radius of the well is 0.5 feet, estimate the drawdown in feet for a well 50 feet away

Answer 1

`d_2=-8.32ft`

Explanation:

From the question we are told that:

Height of first draw down
`h=30`

Pump Discharge
`Q=250gallons/day`

Well 1 depth
`d_1=10ft`

Transmissivity
`\=T 10.0 ft2/day`

Radius
`r=0.5`

Well 2 depth
`d_2=50ft`

Generally the Thiem's equation for Discharge is mathematically given by

`Q=(2\piT(h_2-h_1))/(ln((r_2)/(r_1)))`

`250=(2*\pi 10 (10-d_2))/(ln((50)/(0.5)))`

`1151.293=2*\pi 10 (10-d_2)`

`d_2=-8.32ft`