PUBLIC HEARING: Consider Request for an Amended Conditional Use Permit to Expand an Existing Natural Gas Substation at 7607 173rd Ave NW (Project No. 22-119); Case of CenterPoint Energy

CenterPoint Energy (the "Applicant") has applied for an Amended Conditional Use Permit to expand their natural gas substation at 7607 173rd Avenue NW (the "Subject Property") with the installation of a 12,000-gallon odorant tank and associated equipment.

The City attempted to send a mailing via Standard U.S. Mail to property owners within 350 feet of the Subject Property, as noted in the Anoka County Property Records, notifying them of the public hearing. The notice was also published in the Anoka County UnionHerald.

The Subject Property is about 13.60 acres in size and is zoned R-1 Residential (Rural Developing).  The 2040 Comprehensive Plan guides the Subject Property as Public.  Essential Services are a Conditional Use in the R-1 Residential District.  The surrounding properties are zoned R-1 Residential (Rural Development) and are guided as Rural Developing.  Surrounding property sizes range from about 0.90 acres (south of 173rd Avenue) to 40 acres.

The Applicant intends to install a 12,000-gallon odorant tank and associated equipment on the Subject Property.  Additionally, the Applicant will be adding four (4) inches of class V gravel to the entrances and maneuvering areas.  They are not proposing any modifications to existing access points nor are they proposing any additional access points.

During the colder, heating season months (generally considered November - March), the Applicant's personnel would access the Subject Property approximately 3-4 instances per month with 1-ton or 2-ton pick-up trucks that have been modified to carry the odorant.  On site, they would use the storage tank to fill their trucks and then travel to various odorant injection sites throughout the state to disperse the odorant into the natural gas.  The storage tank itself would require filling about 4 times per year (again, over the colder, heating season months, it would likely require filling 2-3 times, and over the remainder of the year, one additional filling).  This is accomplished via a tanker truck.

In addition to the odorant storage tank, the Applicant is proposing the installation of a small (10' x 10') equipment building, security fencing, a security light, and a twenty-five foot tall flare.  The flare is necessary to control pressure within the storage tank during filling procedures for both the bulk storage tank and the odorant trucks.  Personnel would be on site at all times while flaring is occurring.  Flaring would last approximately 20 minutes per occurrence and would only be done during normal, daytime business hours, reducing the visible light to an almost non-detectable level.

In the late 1990s, the Applicant received a Conditional Use Permit to add a Peak Shaving Plant to the substation operation on the Subject Property.  That part of the operation ceased in 2003.  However, there are still remnants of that system on the Subject Property.  As part of this project, the Applicant would be removing the remaining portions of the former tank foundation and building slabs, as well as the old security fencing.  As previously noted, new security fencing is being installed but the Applicant is keeping it about five (5) feet inside the old fence location to avoid removal of large diameter trees (clearing/grubbing will be necessary within the fenced area).

Alternatives

Alternative 1: Recommend approval of the Amended Conditional Use Permit for expansion of the natural gas substation on the Subject Property.  The footprint of the natural gas substation is not changing, there would just be additional equipment installed on site.  There is sufficient maneuvering area for a tanker truck to enter the site, fill the storage tank and exit back onto 173rd Avenue without disrupting traffic.  Personnel would be on site any time flaring occurs and said occurrences would only occur during regular, daytime business hours, reducing the visible light from the flare to a nearly non-detectable light source.  Staff supports this option.

Alternative 2: Recommend denial of the Amended Conditional Use Permit.  There is already a Conditional Use Permit for a natural gas substation on the Subject Property.  Essential Services are a Conditional Use in this zoning district and the Subject Property is guided as Public in the 2040 Comprehensive Plan, which is appropriate for a substation.  Staff does not support this alternative.

All costs associated with this request are the Applicant's responsibility.

Staff recommends approving the request for an Amended Conditional Use Permit.

Motion to recommend City Council adopt Resolution #22-093 granting an Amended Conditional Use Permit to expand the substation with an odorant storage tank and associated equipment.