Hello and thank you for your inquiry.

Do you have this juniper already in hand, or you thinking about planting this near your drinking water well?

I am not finding exact information about the root structure for this type of Juniper, but it does seem that this is a type that is more slow-growing and stays more compact, with woody roots growing downward but also horizontally closer to the surface. 

If you have information about spacing, this might serve as a guide as to how far away from your well you may need to plant away so that you can avoid any damage to your well.Typically, there is a concern about planting trees and shrubs with woody roots and avoiding damage to septic system drainfields.

If you have further specifics about suggested spacing for this plant, that would be great. In the meanwhile, I am checking in with some individuals about planting details with regard to drinking water wells.

On Tue, Jun 8, 2021 at 1:59 PM, Ask Extension

<<personal data hidden>> wrote:

I got some additional information from a staff member from a local Health Department who share this information:

"There is no established minimum isolation. The problem with planting shrubs and trees close to a well is it becomes hard for a well rig to get to the well in the event repairs are needed. My recommendation is nothing within 20 feet."

In addition, one of our MSU Extension Consumer Horticulture Eduators share this: 

"These plants don’t get very large. I would estimate the root system, even at full maturity, would never be more than 3’."

Hope this extra info. is helpful.

On Wed, Jun 9, 2021 at 1:17 AM, Ask Extension

<<personal data hidden>> wrote:

Glad we could help!