A communication transmitted from Yi-An Huang, City Manager, relative to an update on the successful completion of the 221 Mount Auburn Street demolition.

Council Update May 11, 2026 1 221 Mount Auburn Street Riverview Condominiums

2 Today’s Discussion History of Development City Involvement Demo & Progress Photos Update on Costs What’s Next? 1 2 3 4 5

3 Staff – Deep Appreciation I know I am missing some, but this is an indication of how comprehensive an effort this has been.

205 WESTERN AVE History of Development 4

5 History of Development Riverview Property – Two separate buildings: 221 Mount Auburn Street – 9-story concrete structure with 66 units 3-story wood and brick Bradbury Building with 14 units

6 Structural Issues Identified • 2023 preparatory work for roof and drainage improvements to address leakage and ponding issues included coring new holes in the cantilevered balconies. • SGH evaluated the capacity of the slabs throughout the building Utility Penetrations Deterioration from Leakage & Corrosion Previous Concrete Repair Work Low Reinforcement Low Concrete Compressive Strength Delivered to the City April 28, 2025

7 Punching Shear -- The slab needs to be strong enough to support the weight Structural Issues Identified

8 Slab Column Structural Issues Identified

9 Asbestos Consistent with buildings of this era, chrysotile asbestos was identified in joint compound, floor tiles and popcorn ceilings. Asbestos is a naturally occurring mineral found in the ground. Widely used in buildings due to its fire and heat resistance, durability and insulation until health risks associated with airborne asbestos became apparent. Individual asbestos fibers are too small to see with the human eye. www.mesotheliomahub.com/mesothelioma/asbestos/types-of-asbestos/

205 WESTERN AVE City Involvement 10

11 Timeline for City Involvement • April 2025 – City began regular meetings with owners • Consensus – building must be demolished • City’s involvement is based on public health & safety • July – met individually with all neighbors • In-person meeting July 10th – 80 people • July 19th – Closed Mt. Auburn & Sparks streets • July 22nd – Board or Survey • City Council appropriated $20M on July 23rd. • Zoom meeting July 24th – over 200 people • Zoom meeting October 22, 2025 – meet the team

12 Timeline for City Involvement • Nov 17, 2025 – Jan 31, 2026: 205 Mt Auburn Street residents (17 units) temporarily vacated Demolition Progresses smoothly, under budget and without incident Speaks to the quality, skills and dedication of the full team of staff and contractors working on this project

205 WESTERN AVE Demo & Progress Photos 13

14 Site Overview Two separate buildings: 221 Mount Auburn Street – 9-story concrete structure with 66 units – Demolished 3-story wood and brick Bradbury Building with 14 units – Remains in place

15 6 Phases of Demolition – Timing of Phase 3 Critical Residents of the 17 units at 205 Mt Auburn temporarily evacuated, through Phase 3

16 Pre-Demo Preparation • Air quality monitors installed & approved by DEP • DEP site inspections (20+ throughout demo) before and after each phase – confirm consistency with Non-Traditional Work Plan (NTWP) • Fire Department inspections to ensure they were prepared to respond to an incident • Temporary power for trailer and monitoring • 17 units at 205 Mt Auburn temporarily evacuated, through Phase 3

17 11.2020

18 Week of 12.22.25 – Phase 1 Balconies

19 Week of 12.29.25 – Phase 2

20 Week of 12.29.25 – Phase 2

21 Week of 1.12.26 – Phase 3

22 Week of 1.19.26 – Phase 3 Complete Residents of 205 Mt Auburn can prepare for return

23 Week of 1.26.26 – Phase 4

24 Week of 2.2.26 Phase 5

25 Week of 2.9.26 Phase 5

26 Week of 2.16.26 – Final Demolition

27 Week of 3.2.26 – Removal of Material

ZERO EXCEEDANCES Recycled Scrap Metal 400 tons 895,000 lbs 49 truckloads REGULATORY CRITERIA MET Asbestos Containing Building Materials 11,000 tons 22,000,000 lbs 365 truckloads Building Materials Removed from Project Site TOTAL BUILDING MATERIAL WASTE TOTAL Debris Removed 11,500 tons 22,895,000 lbs

29 Extensive Air Monitoring – Permitted by MassDEP Vibration Montoring 190,000+ Readings Recorded Air Monitoring 10 Perimeter Devices for Optimal Coverage 34,560+ Data Points Recorded 300+ samples evaluated ZERO EXCEEDENCES all below 0.002 f/cc

30 • April 9, 2026 Final DEP Site Visit and Closeout • April 17, 2026 Streets reopen!! Site remains fenced off. • Final site work estimated to be complete in next 2 to 4 weeks, return control of site to owners April 1, 2026 – Last Truck Departs 4.1.26 All Hauling is Complete & Shifting to Final Closeout

205 WESTERN AVE Update on Costs 31

32 Estimate to Complete is approximately $12M * Subject to Change, pending final completion & reconciliation Appropriated $20M on July 23, 2025 – Conservative estimate to address contingencies Engineering and Oversight – SGH, TRC, Kleinfelder, STV • $1M Construction – Consigli, NorthStar, Traffic Management • $10.5M 205 Temporary Relocations – 17 units for 2 ½ months • $250,000 We are not including any costs for city staff

205 WESTERN AVE What’s Next? 33

34 No identified timeline for the redevelopment of the site. Land Court has appointed a Commissioner to oversee the sale of the parcel, including reimbursing the City for demo expenses. New owner will develop proposals for redevelopment. There are many nuances associated with zoning and development that would be worked through as part of a redevelopment process. Redevelopment of the Site

35 Along Mt. Auburn Street – Residence C-2, allows multifamily housing up to 7 stories above grade (85 ft). Rear section – Residence C-1, allows multifamily housing up to 6 stories above grade (74 feet), if the housing meets inclusionary housing requirements. Inclusionary housing means that some units are required to be affordable to low- and moderate-income households. Developments of at least 10,000 sq ft or 10 units of housing must meet inclusionary housing requirements. Projects that are larger than 75,000 sq ft require special permit approval by the Planning Board, including public hearings. Zoned Residential Zoning of Site 2-acre parcel & 100,000 sq fit of buildings