Document Library
Every public project document in one place, searchable, categorized, and written in plain language. Every document includes a "Why this matters to you" summary.
Project Site Plan
This engineering plan shows where the battery units, access roads, setbacks, fencing, stormwater features, and landscaping sit within the 15-acre project area.
Critical Issues Analysis
This early study checks the site for environmental, structural, and regulatory problems that could stop the project before design work goes further.
Site Elevation Map
This map shows the elevation changes, natural contours, and grading needs across the Carpenter Hill site.
Preliminary Wetlands Index
This early map identifies the wetland areas on the property and next to it.
Site Aerial Map
This high-resolution aerial photo shows the project footprint next to surrounding properties, roads, and vegetation.
Detailed Project Location Map (1-Mile Landmark Map)
This two-sheet map meets the state pre-filing rule 980 CMR 16.09(1)(a)3. Sheet 1 shows the project boundary, the battery equipment area, the access road, the interconnection route to the Carpenter Hill substation, and the schools, parks, library, medical facilities, and other community landmarks within one mile of the project boundary. Sheet 2 lists every landmark with its address, coordinates, distance, and the sources we used to verify it. Component locations reflect the current preliminary design.
Tesla Megablock / Megapack 3 Technical Specifications
This data sheet lists the dimensions, capacity, safety features, and performance figures for the Tesla Megablock / Megapack 3 battery unit.
NFPA 855: Plain Language Summary
This page summarizes NFPA 855, the national fire protection standard for battery storage. It covers siting, fire suppression, ventilation, and emergency response requirements.
UL 9540A Testing: What It Means
This explainer describes the UL 9540A fire safety test, what the test measures, and what the results mean for the Carpenter Hill project.
Emergency Response Planning Framework
This framework outlines the site-specific emergency response plan we are developing with Charlton Fire Chief Rob Barton. It covers incident command, notification, and mutual aid.
2024 Climate Act (Chapter 239): Summary
This summary explains the 2024 Climate Act's rules for siting energy facilities, including the consolidated permit process the EFSB now runs.
Intervenor Support Grant Program
This official Mass.gov page describes the state's Intervenor Support Grant Program. The 2024 Climate Act created the program, and the Department of Public Utilities runs it. It pays community groups up to $150,000 per proceeding for attorneys, expert witnesses, and other costs of taking part in EFSB and DPU cases that begin on or after July 1, 2026.
980 CMR 16.00: Consolidated Permit Regulations Overview
This overview explains the EFSB regulations for the consolidated permit process, including pre-filing requirements and community engagement obligations.
Community Engagement Plan (July 2026 Update)
This plan explains how we engage the Charlton community during the state pre-filing period under 980 CMR 16.00. It lists the stakeholders we are reaching, the state and local agencies we consult, every meeting held and planned through the fall, and the regulatory milestones ahead. This July 2026 update builds on the April plan and adds the items the OEJE asked for.
OEJE / DPP Pre-Filing Engagement Meeting Minutes
These are the official minutes from our kick-off meeting with the Office of Environmental Justice and Equity and the Department of Public Utilities to review compliance under 980 CMR 16.00.
Medway Grid Battery Project (Approved Reference Project)
This is the official EFSB docket page for the Medway Grid battery project, a facility the state has already approved.
Cranberry Point Energy Storage (Approved Reference Project)
This is the official EFSB docket page for the Cranberry Point energy storage facility, another approved project.
Inaugural Citizen Advisory Committee (CAC) Meeting Minutes
These are the official minutes from the first Citizen Advisory Committee meeting, held on June 3, 2026. The committee discussed community identity, expectations, safety concerns, and benefit plan priorities.
Public Meeting #1 Station Posters (July 8, 2026)
These are the four posters we displayed at the July 8 public meeting: the project location map, the grid reasons this site works, the Megapack safety layers, and what we know about the land, water, and trees on this parcel.
Public Meeting #1 Dot Boards & Comment Cards (July 8, 2026)
This file shows the input residents gave at the July 8 public meeting: the dot board where attendees marked what a Community Benefits Plan should focus on, the topic list our team logged at the record table, and the anonymous exit cards from the box by the door.
US Grid-Scale BESS Incident Briefing Binder
This binder compiles 15 grid-scale battery fire and thermal runaway incidents in the United States between 2018 and July 2026, with root causes and safety outcomes.
ACP BESS Fire Impacts Report (2025)
This American Clean Power report analyzes battery storage fire incidents across the industry, including safety statistics and environmental testing results.
Tesla Megapack 2/2XL Fire Protection Engineering (FPE) Report
This Fisher Engineering report analyzes fire protection for the Tesla Megapack 2 and 2XL energy storage systems.