Hydrology Division

  Notice of Intent and Well Permit Review                                                                                                                                                                       

When an application for a well permit or a Notice of Intent (NOI) to drill/modify a well is filed with ADWR, the proposed well or modification is evaluated with respect to its location and the boundaries of remedial action sites.  If the proposed well is within the boundary or the buffer zone of a remedial action site, the application or NOI is flagged for technical review by the Water Quality Unit.  You can determine if a proposed well is within the boundary of a remedial action site or its buffer by reviewing the groundwater basin maps available for download.  The maps show the extent of the groundwater basins and include townships, ranges, sections, and the boundaries and buffer zones of remedial actions sites. 

The Water Quality Unit verifies that the proposed well construction or modified construction meets minimum well construction and any applicable site-specific special well construction requirements.  Well construction requirements minimize the potential for vertical cross-contamination and not cause migration to a contaminate plume.  In all cases, the construction design must be protective of the aquifer.   A detailed well diagram is helpful to ADWR's review of applications.

 

Potential for Vertical Cross-Contamination


Local geological information is incorporated into the review to determine if the well may act as a conduit for vertical cross-contamination within the aquifer or between aquifers.  If a well may act as a conduit for vertical cross-contamination, the well construction design must be revised to minimize the potential threat to groundwater quality or the application may be denied.  Special well drilling techniques, such as sealing off a water-bearing zone during drilling, may be required.

 rain drop  See an Animation of Vertical Cross-Contamination Through Casing Flow (pps)

 rain drop  See an Animation of Vertical Cross-Contamination Through Annular Flow (pps)

                        

Contaminant Plume Migration


The proposed withdrawals from the new well are evaluated to determine if the withdrawals may cause the migration of a contaminant plume such that it will cause increasingly unreasonable damage to other land and water users.  If the withdrawals cause damage to other land wand water users, the applicant can mitigate the impacts of the proposed well by:

 rain drop  Reducing the withdrawals rates

 rain drop  Altering the well construction design

 rain drop  Moving the well to another site, or

 rain drop  Obtaining a waiver from the affected party

If these mitigation efforts can not be accomplished, the application may be denied.

                        

Well Construction Diagram


ADWR recommends that Notices of Intent include a detailed well construction diagram that depicts the major well construction materials and specifications.  A detailed well construction diagram is required for well permit applications (in Active Management Areas).  Please feel free to download the appropriate well construction diagram below and submit it with your Notice of Intent.

Well construction diagrams should indicate the following features:

 

 rain drop  Borehole Depth

 rain drop  Borehole Diameter

 rain drop  Casing Material (steel or thermoplastic)

 rain drop  Casing Length and Diameter

 rain drop  Width of Annular Space between the 

     casing and the borehole

 rain drop  Surface Seal (20-feet of steel casing

     from one foot above ground level.  The

     seal shall be cement grouted from        

     bottom of zone to land surface).  When

     inner and outer casings are installed, the

     annular space between the casings shall

     be completely sealed.

 rain drop  Access Port

 rain drop  Annular Material (specific type of grout

     and gravel pack)

 rain drop  Expected Depth to Water

 rain drop  Screening Materials and Perforated

     Intervals (in feet)

Label each feature of the well with its’ corresponding depth below land surface.

When a well is being modified, the diagram should include the original well construction and highlight the modifications that are being proposed.  Label all components with labels such as “Existing 20-inch casing” or “New 16-inch casing.”  If the well is being abandoned, include a diagram of the existing well construction and the abandonment plan. 

In all cases, well construction must be protective of the aquifer and satisfy minimum well construction requirements.  Special well construction requirements may apply to wells being drilled or abandoned in or near a remedial action site.    Knowledge of the geology near your proposed well site is crucial.

                        

Special Well Construction Requirements


An applicant can determine if their proposed well is in an area subject to special well construction requirements by reviewing the groundwater basin maps and checking this website before drilling.  Site-specific special well construction requirements will occasionally be added.

 



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