Engineer: proposed monopine tower is designed to keep any failure inside fenced site; board seeks legal opinion on fall-zone rule

Shazad Mummud, a Kimley Horn representative working for SBA Communications, and Chris Lawson, a sales application engineer at Valmont Industries, told the Gardner Zoning Board of Appeals on June 16 that the proposed 128–130-foot monopine telecommunications tower would be engineered so any structural failure would remain inside the site enclosure and not reach the Walmart facility.

Lawson said the tower’s design follows industry standards and a stamped fall‑zone engineering report will model a theoretical failure radius. “The wind that this structure will be designed to is 118 miles per hour,” Lawson said, citing American Society of Civil Engineers guidance and an interpolated gust for the tower height. He described three primary failure modes—base‑plate weld failure, foundation failure and pole buckling—and said the design approach is to overdesign base and foundation so the likely failure would be a ductile bend in a midsection rather than a sudden collapse.

The project team told the board the site would include a 50‑by‑50‑foot fenced enclosure around the tower, placing the pole at the center so the enclosure edge is about 25 feet from the tower center. “When you say it’s a zero foot fall zone, that means we have to keep it within wherever the enclosure is for the site,” Lawson said, adding, “we do not believe that it’s going to completely snap off and fall into the parking lot.” He also described preliminary section capacities for the slip‑fit pole sections (L1 ~68%, L2 ~98%, L3 ~78%, L4 ~91%) and identified L2 as the most likely buckle location in worst‑case loading.

Board members pressed whether the engineered “crumble” or controlled‑failure approach satisfies Gardner’s fall‑zone ordinance, which the board read as requiring a fall zone equal to the tower height (130 feet) that must be clear of property lines, public roads, habitable dwellings, and certain public uses. One member said a 130‑foot radius, as written in the code, would intersect the Walmart parking area and could therefore conflict with the applicant’s assertion that failure would remain within the wooded parcel. “I feel the safest route for everybody is go legally through our city solicitor,” Bob Rice, a member of the board, told the applicant and colleagues.

Board members voted to request a legal opinion from the city solicitor to interpret the ordinance and to continue the hearing to July while they await that guidance; the board said it would not charge the applicant an extension fee for the continuance. Members discussed procedural options with the applicant, including filing a variance now and withdrawing it later if the solicitor determines a variance is unnecessary; staff warned that filing and posting deadlines could delay consideration into August if left until after the opinion.

The applicant said SBA maintains quarterly site inspections through regional site managers, logs inspection reports and can provide Certificates of Insurance and removal bonds if required; the team recounted a rare historical example of foundation uplift during Hurricane Katrina and noted that extreme weather beyond code design parameters or deliberate destruction remain outside routine design assumptions. The company also said jurisdictions have required removal bonds of roughly $30,000–$40,000 in past cases and that abandonment clauses typically require removal after about a year of inactivity.

The board recorded case number 20260302 for the record, agreed to request an expedited solicitor opinion on fall‑zone interpretation and continued the hearing to July; the meeting was then adjourned.

Next steps: the board will send the solicitor the applicant’s fall‑zone report and site documentation, the solicitor will issue an interpretation about whether the ordinance requires a 130‑foot clear radius or if engineered containment can satisfy code (and whether a variance is required), and the ZBA will reconvene in July.