Secaucus, N.J. Assessor’s own worksheets value 2 data centers $18.2M–$24.7M above partial tax rolls

HUDSON TV EXCLUSIVE

By Julio Reynoso, Publisher & Editor

SECAUCUS, N.J. — Handwritten valuation worksheets from the Secaucus Tax Assessor’s Office released under the Open Public Records Act show that two major data-center properties in town — a completed 389,578-square-foot Hartz Mountain / Equinix facility at 600–650 Jefferson Ave. and CoreSite’s expanded campus at 2 Emerson Lane — carry finished assessor valuations that exceed their “partial” property-tax assessments by $18,233,895 on the 2025 tax rolls ($24,687,795 when compared against 2 Emerson Lane’s 2024 net assessment), while two other flagship Hartz / Equinix data centers have sat on unchanged “partial” assessments for three consecutive tax years.

The internal assessment records, released by Secaucus Town Clerk Michael Marra on Oct. 1, 2026 in response to OPRA Request No. OPRA-Req-26-1285 and obtained by Hudson TV on Tuesday, surface hours before Mayor Michael Gonnelli and the Town Council meet tonight at 7:00 p.m. to introduce Ordinance 2026-34, a proposed 80-megawatt cap on future data centers that follows 125 megawatts of already-approved Equinix and CoreSite expansions and sits on the same Oct. 27 council agenda as two resolutions fixing residential tax-assessment errors where homeowners were overbilled.

$12.59M below the Assessor’s own math: Hartz and Equinix’s finished 389,578-sq-ft data center at 600–650 Jefferson Ave.

Pages 41 through 44 of the Oct. 1, 2026 OPRA production trace the valuation of Block 30, Lot 4.04 (listed as 650 Jefferson Avenue on the tax rolls and 600 Jefferson Rd on the zoning certificate), an 18.643-acre parcel owned by 600 Jefferson Ave LLC c/o Hartz Mountain and leased to Equinix, Inc. (identified on the Property Record Card as NY3 DATA).

According to Certificate of Completion CT 22-024 ( of the OPRA packet), issued by the Town of Secaucus Engineering and District Zoning Department on Sept. 12, 2024 to owner 600 Jefferson Ave LLC c/o Hartz Mtn and applicant Masoud Zafaripour, Equinix, Inc., the town conducted a final inspection on June 19, 2024 and formally closed the file on:

• Partial demolition of the prior 276,000-square-foot warehouse building;
• Conversion of the building into a data center with a footprint of approximately 217,772 square feet and a gross floor area of 389,578 square feet — comprising 341,355 square feet of disaster-recovery/data-center space and 48,223 square feet of office use;
• Site improvements including electrical equipment, fencing, curbing and asphalt, plus three cooling modules, one tank and three generators installed under the permit; and
• A 134-foot elevated, enclosed pedestrian footbridge connecting the northwest corner of the 600 Jefferson building to the southeast corner of the 755 Secaucus Road Equinix data center (Block 30, Lot 4.03).

Immediately preceding that Certificate of Completion in the OPRA file is , a handwritten accounting worksheet from the Tax Assessor’s file titled “Value Calculation Block 30 / Lot 4.04.” Using the exact square footages from the Sept. 12, 2024 Certificate of Completion, the Assessor’s worksheet calculates the finished value of the building:

• Original Assessment (276,000 sq ft warehouse after 80% demolition): Building only $2,306,500; Total $7,433,300 (with $5,126,800 land).
• New Building (389,578 sq ft):
  • Data Center space: 341,355 sq ft @ $375/sq ft = $128,008,125
  • Office space: 48,223 sq ft @ $200/sq ft = $9,644,600
• Total As Finished: $137,652,725
• Equalized Assessment at .37 Ratio (37%): $50,931,500 (exact product: $137,652,725 × 0.37 = $50,931,508.25, rounded to $50,931,500 on the worksheet).

Yet on the official Property Record Cards for Block 30, Lot 4.04 (Pages 43 and 44 of the OPRA packet, printed March 18, 2025, following a July 17, 2024 inspection notation), the property was never placed on the tax rolls at $50,931,500:

• 2023 & 2024 Base Assessment: Land $5,126,800 + Improvements $2,306,500 = $7,433,300 (reflecting the Dec. 2022 DEMO 80% reduction of $9,225,800 from the prior $11,532,300 improvement value).
• 2024P (Partial / 3-Month Added Assessment 7/24 2024AA 3MOS (+24,000,000) NY3 DATA): Land $5,126,800 + Improvements $30,306,500 = $35,433,300 — which was $15,498,200 below the Assessor’s $50,931,500 finished calculation.
• 2025 Net Taxable Value (PRC Top Header, printed March 18, 2025): Still carrying the header notation Addl Lots: PARTIAL, with Land at $5,126,800 and Improvements at $33,211,500 for a Net Taxable Value of $38,338,300 — leaving an exact gap of $12,593,200 below the Assessor’s $50,931,500 finished worksheet figure.

At Secaucus’s verified 2025 property-tax rate of $4.268 per $100 of assessed value, that $12,593,200 gap on 600–650 Jefferson Ave. alone represents $537,477.78 per year in unbilled property taxes.

A second handwritten Assessor worksheet on : CoreSite’s 2 Emerson Lane calculated at $53,997,195

Five pages earlier in the same OPRA packet (), the Town Clerk produced a second handwritten Tax Assessor worksheet labeled “57/5 — 2 EMERSON DATA CTR” for Block 57, Lot 5 (10.19 acres at 2 Emerson Lane, owned by CoreSite RE 2 Emerson Lane LLC).

of the OPRA packet shows that on July 10, 2023, Secaucus issued Construction Permit No. 23-428 (Control No. CR-23-107) to CoreSite RE 2 Emerson Lane LLC and contractor DPR Construction for ground-up construction of a four-story, 156,200-square-foot data-center building on the site, with an estimated construction cost of $72,350,000. On , the Assessor’s handwritten worksheet calculates the total value across the campus buildings:

• BLD 1A: 35,100 sq ft × $200 = $7,020,000
• BLD 1B: 235,000 sq ft @ $375 = $88,125,000
• BLD 2: 156,000 sq ft × $275 = $42,900,000
• Pkg DECK (Parking Deck): $7,500,000
• Total Building Value: $145,545,000
• Equalized Value @ 37.10 (Assume Complete Fit out): $53,997,195 (handwritten on the bottom line as $53,997,145 / $53,997,195; shows a companion scratch calculation summing BLD 1B’s $88,125,000, BLD 2’s $42,900,000 and the parking deck’s $7,500,000 to $138,525,000).

However, the 2023, 2024 and 2025 Real Property Extended Tax Duplicates (Pages 13, 30 and 35) and the Tax Collector’s account ledger (Pages 14–15) show that Block 57, Lot 5 has remained flagged E *PARTIAL* for three straight years, below the $53,997,195 building fit-out figure:

• 2023 Extended Tax Duplicate (): Flagged E *PARTIAL* — Land $2,801,700 + Improvements $34,402,500 minus a $755,600 automatic fire-sprinkler exemption = $36,448,600 Net Total ($1,446,644.93 original tax billed; $1,521,063.68 with Q4 adjustment).
• 2024 Extended Tax Duplicate (): Flagged *PARTIAL* — Land $2,801,700 + Improvements $39,856,500 minus $755,600 exemption = $41,902,600 Net Total ($1,714,654.39 original tax billed; $1,903,909.39 with $278,557.50 Add/Omit adjustment) — a $12,094,595 gap below the $53,997,195 worksheet figure (and a $14,140,695 gap on the improvement line alone).
• 2025 Extended Tax Duplicate (): Still flagged E *PARTIAL* — Land $2,801,700 + Improvements $48,356,500 minus $755,600 exemption = $50,402,600 Net Total ($2,151,182.97 tax billed) — leaving the 2025 building/improvement assessment ($48,356,500) still $5,640,695 ($5,640,645 against the handwritten $53,997,145) below the Assessor’s $53,997,195 complete fit-out building calculation (worth $240,744.86 in 2025 taxes at $4.268 per $100), or $3,594,595 below $53,997,195 even when counting the $2,801,700 land value inside the $50,402,600 net total.

Three years of static “partial” assessments at 800 Secaucus Road and 755 Secaucus Road

Beyond the two properties with handwritten valuation worksheets, the 2023, 2024 and 2025 Extended Tax Duplicates (Pages 9–12, 26–30 and 31–35) reveal that two other major Hartz Mountain / Equinix data centers in Secaucus have sat on completely unchanged E *PARTIAL* assessments for three consecutive years:

Zero personal property or telecommunications equipment filings on record

In addition to real-property assessments, Item 4 of OPRA Request No. OPRA-Req-26-1285 asked the Town of Secaucus for copies of any local tax assessment records or filed PT-10 / business personal property tax assessment forms concerning local taxable equipment or real-property fixtures at the data centers. On of the Oct. 1, 2026 response letter, Town Clerk Michael Marra certified: “The Town has no records in response to your request.”

Marra likewise certified on (Items 2 and 3) that Secaucus has “no records” of any Payment in Lieu of Taxes (PILOT) agreements, Five-Year Exemption and Abatement agreements, or council resolutions approving tax exemptions or abatements for the data-center parcels from Jan. 1, 2015 to the present.

What it means for Secaucus homeowners ahead of tonight’s 7:00 p.m. council vote

When commercial or industrial properties remain on partial assessments below their finished equalized valuation, the remaining share of the municipal, school and county tax levy is borne by the rest of the town’s tax base. Across the 2023, 2024 and 2025 Extended Tax Duplicates included in the OPRA response, Secaucus’s total property-tax rate rose from $3.969 per $100 of assessed value in 2023 to $4.092 in 2024 and $4.268 in 2025 (reaching approximately $4.558 per $100 on 2026 tax bills).

Secaucus and Hudson County homeowners who want to check whether their home is over-assessed compared to neighboring properties or see how municipal and county tax-rate increases affect their bill can run a free check using GardenState.ai’s Property Tax Appeal tool and model upcoming rate changes with the Tax Shock calculator.

Tonight at 7:00 p.m. at 1203 Paterson Plank Road, Mayor Gonnelli and the Town Council are scheduled to vote on first reading of Ordinance 2026-34, which would cap future data centers in the town’s locally zoned Light Industrial A and B districts at 80 megawatts of electric load and 25,000 gallons per day of water use — while leaving the New Jersey Sports and Exposition Authority (NJSEA) Meadowlands zone, where the town’s largest data centers sit, outside municipal zoning control. As Hudson TV reported Monday, Town Administrator Gary Jeffas admitted in an Oct. 26 email that he “did not review specific plans” for either CoreSite’s 446,761-square-foot expansion at 215 County Ave. (approved 5-0 by the Secaucus Zoning Board in May) or Equinix’s 50-megawatt expansion at 800 Secaucus Road.

Hudson TV has requested comment from Mayor Michael Gonnelli, Town Administrator Gary Jeffas, Tax Assessor Michael Jaeger, Town Clerk Michael Marra, Hartz Mountain Industries, Equinix and CoreSite regarding why Block 30, Lot 4.04 (600–650 Jefferson Ave.) remains assessed $12,593,200 below the Assessor’s $50,931,500 finished worksheet valuation more than a year after receiving its Sept. 12, 2024 Certificate of Completion, why Block 57, Lot 5 (2 Emerson Lane) and Block 23, Lot 4.02 / Block 30, Lot 4.03 (800 and 755 Secaucus Road) remain marked “partial” across the 2023–2025 tax rolls, and when full assessments will take effect. This story will be updated with any responses received.

Hudson TV asks: Should Secaucus conduct an independent audit of all “partial” data-center tax assessments before voting on new data-center rules tonight? Reply A: Yes, audit every data-center assessment now. Reply B: No, current assessments are sufficient.
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