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----- Original Message ----
From: vivek gupta <jazzvivek_2002@...>
To: visual-modflow@...
Sent: Sunday, October 29, 2006 9:43:35 AM
Subject: Re: [visual-modflow] Pumping Well Schedule...

Dear Yash..

Thank you for ur intelligent reply. Sir, some more things i wanted to ask u,
As i m a beginner in Modeling, so i m seeking some more help frm u...

1) Does MODFLOW account for the pumping hrs or it only accounts for the
pumping days, because of the fact that pumping schedule in MODFLOW should be
throughout the stress period.

For your test you will be taking only one unit it may be days or hours whichever
suits to your problem. But for one cycle of analysis it will be a single unit.

2) I want to calibrate the model for 2 years transient period, I have weekly
groundwater data, can u suggest me how should i divide this 2 yrs in to stress
period and time steps for getting good results.

You can take stress period in hours/days and give it as a zero value for one
stress period. Actually the unit will depend on your objective what you want to
get.

3) Actually Sir I m doing 2D modeling, and i have the case of a confined
aquifer, i.e. top layer confined, confined aquifer and again layer. and i want
to model the saturated thickness as my model layer, but the problem is that a
river which i have to use as a Cauchy boundary condition, is partially
penetrating upto only upper confined layer ( river bed elevation is above the
saturate thickness of aquifer), so how can i use this river as a cauchy boundary
without (perhaps)any hydraulic connection between them.

If you have confined layer then river or anything outside is not going to matter
and to have effect of river it should be unconfined and you can take total
amount of water in yours layer as fixed i.e. if water coming from river by
seepage it goes out from the other side of layer by gradient.
.

4) The properties( T & S) and the boundary conditions that i will be
assigning, will that be only for the saturated thickness(model layer) or i have
to assign those for the top layer too.

If you have confined layer then then need not to assign for upper layers. but
its betetr to assign as while writing paper you will need these

Thanks again for ur fast response, I m again lookin forward for ur fast reply,
it will help me assist in my project.

With Best Regards
Vivek Gupta


Yashpal Saharawat <yash_saharawat@...> wrote:
Dear Vivek

You can give pumping rate as 0 pumping rate during the non-pumping period and
you should use actual well screen thickness.

cheers...
yash


----- Original Message ----
From: vivek gupta <jazzvivek_2002@...>
To: visual-modflow@...
Sent: Friday, October 27, 2006 11:39:46 AM
Subject: [visual-modflow] Pumping Well Schedule...

Hi all...

I m doing 2D transient GW modeling using Visual MODFLOW. I m facing some problem
while entering pumping schedule. The problem is that MODFLOW allows a continuous
pumping schedule, but in my study area pumping is intermittent, like in rainy
season 15 days in a month will be used for pumping, rest 15 days sustain with
rain, i explain my prob with an example..( I have the case of constant pumping
rate in one particular well site)

suppose i have following pumping schedule for one of the well...
jan- daily, 10h , -16 lps
feb- daily, 10h, -16 lps
mar- daily, 10h , -16 lps
apr- daily, 10h, -16 lps
may, daily, 10h , -16 lps
june, 15 days, 6h, -16 lps
july, 10 days, 6h, -16 lps
AUG, daily, 6 h, -16 lps
.
. and so on.

Now while entering in MODFLOW i can't take account of those 15 days of june and
july in which no pumping had been done, because MODFLOW allows continuous
pumping schedule and the pumping schedule has to be through-out the full
transient period, thats y i could'nt follow the continous pumping schedule too.

so the only way out is...suppose if i have 2 yrs transient stress period with a
constant pumping rate, the pumping schedule will be..
start day stop day pumping rate(LPS)
o 720 -16

I want to check my above mentioned conclusion..suggestions are heartly
welcomed.

ALSO another question is that in 2D modeling shud the pumping wells' screen
thickness be entered with full saturated thickness or shud i use the actual well
screen thickness if i have the data of screen locations.

With best Regards
Vivek Gupta
IIT kharagpur