Morris & Gwendolyn Cafritz Foundation Environmental Education Center  


General Information

Building Name: The Morris & Gwendolyn Cafritz Foundation Environmental Education Center
Building Location: Accokeek, Maryland, United States
Project Size: 3000sf
Market Sector: Private | Non-Profit Organization
Building Type: Environmental Education Center
Delivery Method: Design-Bid-Build
Total Building Costs: The costs for this project were embedded in a larger campus construction project of $5.2M; the costs for this building alone were not isolated within this larger budget because larger site and infrastructure work was completed at the same time by the same contractor.
Project Completion Date / Date Building Occupied: Has the building been occupied for a minimum of 1 year following completion?
Final Certificate of Occupancy: October 23, 2015
Date of start of performance period for Living Building Challenge: January 1, 2016
Close of performance period for Living Building Challenge: December 31, 2016
Award of "Living Certified" by ILFI, including Net-Zero Energy: April 2017

Project Team

Re:Vision Architecture
133 Grape Street
Philadelphia, Pennsylvania 19127

One Washington Square. 510 Walnut Street, Suite 1600
Philadelphia, Pennsylvania 19106

Project Management (Owner's Representative)
Consilience LLC
3347 Quesada St. NW
Washington, DC 20015

Facchina Construction Company
102 Centential Street, Suite 201
LaPlata, Maryland 20646
Note: This firm is no longer in business as they were purchased by another firm and dissolved.

Commissioning Authority
Lilker EMO Energy Solutions LLC
3130 Fairview Park Drive, Suite 125
Falls Church, Virginia 22042

High Performance Design Consultant
Re:Vision Architecture
133 Grape Street
Philadelphia, Pennsylvania 19127

Authority Having Jurisdiction
Prince George's County, Maryland

Civil Engineering
Crouse Engineering, Inc
3215 Leonardtown Road
Waldorf, Maryland 20602

Landscape Architecture
10 Shurs Lane
Philadelphia, Pennsylvania 19127

Structural Engineer
1002 West 9th Avenue
King of Prussia, Pennsylvania 19406

Exterior of the Morris & Gwendolyn Cafritz Foundation Environmental Education Center with picture of people gathered on the porch

The design pulls people out of doors and provides multiple ways to be sheltered and outside.


The Morris & Gwendolyn Cafritz Foundation Environmental Center (Cafritz Environmental Center), a 3,000 sf day-use education and events building, is designed to work together with other new campus structures to achieve net zero energy and water targets. The symbiotic buildings include The Cafritz Center (our sun seeking Grass Building), the Moss Lodge (a 7,000 sf dormitory building with classrooms), two sleeping cabins and a wetlands boardwalk. Challenging site conditions encouraged the design team to look to nature for design solutions to address abundant groundwater and sub-par solar access. As a result, the Cafritz Center was conceived as an elongated blade of grass nestled on a woodland edge and the neighboring overnight lodge as dense moss under tree cover.

Interior of the Morris & Gwendolyn Cafritz Foundation Environmental Education Center

The building was designed to be 'sailed' by the occupants to take advantage of daylight and breezes, and buffer from extreme temperatures and includes an interactive building performance dashboard as a teaching tool.

Aerial view of the Morris & Gwendolyn Cafritz Foundation Environmental Education Center site plan

Site plan. Rather than working independently, the sunny "Grass" and shady "Moss" buildings were designed to work together to achieve Net-Zero Energy and Water targets.

With construction completed in October of 2015, the Cafritz Environmental Center is one of the first 15 buildings to achieve the greenest, most energy efficient, high-performance building standard anywhere in the world today: the Living Building Challenge. This beautiful and inspiring state-of-the-art education building is:

  • Averting emission of 70,000 pounds of CO2 per year (100% of the building's annual energy requirements)
  • Producing more energy than it consumes
  • Managing its own waste on site
  • Closing the water cycle
  • Educating thousands of students and visitors who visit the building
  • Demonstrating the power of owner advocacy to achieve change in the manufacturing sector.

For more than 60 years, the Alice Ferguson Foundation (AFF) has been a well-respected and sought after partner for school systems in the region. AFF has served approximately 500,000 students over the decades and nearly 9,000 students this past school year alone. Its new environmental education center provides an inspiring learning space for the students, teachers, and visitors annually.


The recently completed Morris & Gwendolyn Cafritz Foundation Environmental Center is a prototype for the future and is one of a handful of buildings in the world to have achieved full "Living Building Challenge" certification. In keeping with the Foundation's mission, this high-performance green building works in harmony with nature, allowing it to make use of the sun and rain to achieve net zero energy, net zero water, and carbon-neutral facilities. The specific project goals were to:

  • Minimize impact to the environmentally sensitive site
  • Protect the Foundation's open space
  • Preserve the rural and historic character of the Farm
  • Be adaptable, design flexible spaces that can change over time
  • Turn green building strategies into teaching tools
  • Achieve Net-Zero Water to restore local aquifers
  • Achieve third-party verified Net-Positive Energy
  • Make kids the priority - everything is child-centered
  • Be a trash-free facility.
Lower level and Main floor plans of the Morris & Gwendolyn Cafritz Foundation Environmental Education Center

Lower level and Main floor plans

Secure/Safe Goal: The fortitude with which the building has been constructed will help it to stand for hundreds of years, providing shelter and comfort for those who visit. Challenging ground water issues and proximity to floodplain areas encouraged the design team to elevate the main occupiable portions of the building well above the existing grade. The building is constructed with solid cast-in-place foundation walls and piers, engineered and heavy timber framing, and solid roof construction comprised of 10" thick SIPS, and a durable standing seam metal roof. A deep roof overhang on the south side provides shade as well as protection to the large glass windows during very inclement weather. The incorporation of an outdoor fireplace and an indoor wood burning stove allows for a resilient warm shelter in the event that electricity is lost from the grid. The building is daylit, super insulated to allow temperatures to be maintained, and the composting toilets remain functional under all conditions.

Productive & Healthy Goal: Occupant health and well-being was a top goal for the final building, and the metrics that led the team to reach this goal were the requirements of the Red List Imperative of the Materials Petal of Living Building Challenge. Over 450 materials used in the building were vetted for "Red List" chemicals. The red list includes hundreds of carcinogenic, mutagenic, or bio-accumulative toxic compounds or classes of chemicals that are ubiquitous in the economy, such as formaldehyde and PVC. Additionally, it has been ensured that every occupiable space within the building has operable windows that provide access to fresh air and daylight.

3 side by side photos of the lodge aesthetic of the Morris & Gwendolyn Cafritz Foundation Environmental Education Center-left: wood flooring and wainscoting; center: wooden ceiling treatment; right: exterior posts of salvaged wood

In keeping with the Owner's environmental mission and desired 'lodge' aesthetic, the wood flooring, ceiling treatment, and wainscoting were all milled from downed trees on-site. Exterior posts were salvaged from an Amish farm.

Sustainable Goal: In keeping with its guiding principles of Education, Inspiration, and Innovation, the Alice Ferguson Foundation embraced the most stringent set of green building, energy efficiency requirements in the world as they upgraded and enhanced their environmental education campus to meet their goal: to regenerate the environment around them as they construct state-of-the-art buildings that serve as innovating and inspirational teaching tools.

Functional Goal: The program for the building is a multi-purpose space devoted to environmental education; the mix of interior and covered exterior spaces support a variety of programs and events, both indoors and out of doors. Ultimately, the Center is a place to learn about the environment AND demonstrate how to build in a more sustainable and enduring way. This is a building designed to be 'sailed' by the occupants to take advantage of daylight, breezes, views, and indoor-outdoor flow. The Cafritz Environmental Center includes teaching tools to help building occupants develop a more intimate relationship with energy and water, in terms of both production and consumption, as they contribute to the Center's resource usage while striving for its net zero goals.

Accessible Goal: As an educational space for students, teachers, and visitors, the building and its immediate surroundings needed to be ADA accessible and welcoming to all. A requirement of the Living Building Challenge is that "all primary transportation, roads and non-building infrastructure that are considered externally focused must be equally accessible to all members of the public regardless of background, age, and socioeconomic class".

Aesthetic Goal: Given its location on a working farm, the desired aesthetic was warm and lodge-like. Many of the structural and finish materials are milled from the site or repurposed from other buildings. Elements purely for human delight were targeted throughout the building.

Morris & Gwendolyn Cafritz Foundation Environmental Education Center - 3 photos of exterior spaces are designed for four-season enjoyment

Exterior spaces are designed for four-season enjoyment.

Cost-Effective Goal: It became a goal of the team to evaluate building materials and systems that met the best long-term costs for the project—not just the most economical first cost. Durability and maintenance and operations costs were of high importance when selecting components and materials for the building.

Historic Preservation Goal: The Alice Ferguson Foundation's mission is to provide experiences that encourage connections between people, the natural environment, farming, and the cultural heritage of the Potomac River Watershed. As part of this mission, the client is dedicated to creating a structure that preserves and regenerates the land around it. Minimizing site disturbance on the educational farm was essential to the Client and project, which led to compact development on a previously disturbed location and its surroundings.

Other Significant Aspects of the Project: The project team was engaged collaboratively and in tandem to work through refinements and reiterations of the design to produce a building that met the targeting goals in the most efficient manner possible. Energy modeling was used to analyze multiple energy conserving measures to evaluate the best assembly and systems without diminishing returns. Decisions were not based upon first costs but were informed by evaluating first costs against maintenance costs against replacement costs, and finally against environmental costs.

Some tools and methods used to inform the design process included:

  1. A solar pathfinder, to locate and orient the building for optimal winter solar gain and minimize unwanted summer solar gain
  2. eQUEST, for systems selection and analysis
  3. Water balance modeling, to calculate annual predicted water flows and
  4. "Green Footstep" calculator, to benchmark the project's carbon footprint for a deeper understanding of material choices.


Overview of Process

A highly collaborative process with an integrated week-long design charrette was used to engage staff and stakeholders in the design of a Master Plan for a campus of living buildings This project advances the notion of "Living Buildings" by considering what it means to be a Living Campus with interdependent structures and site development. Certified as the 13th Living Building in the world by the International Living Future Institute, the Cafritz Environmental Center has 12–months of operating data to verify its net-zero energy performance and net-zero water performance, among other measures of site sustainability, equity, health, and beauty.

The program that developed out of the pre-design charrette phase identified the following important spaces and qualities of the building:

  1. Outdoor experience is central
  2. There should be a strong connection between inside and outside
  3. Aesthetic should be warm and natural
  4. Building should complement the farm's agricultural character
  5. Building should function somewhat like a church hall
  6. Main group activity area/ meeting/ dining space
  7. Support spaces of a kitchen and bathrooms, and
  8. Covered outdoor spaces for gathering and staging.

Throughout the design process, the design team worked around the premise that the building should pull people out of doors as much as invite them inside, and it should provide multiple ways to be sheltered while outside. Providing diverse exterior spaces allow for four-season education and enjoyment of the natural setting was essential.

This is a building designed to be 'sailed' by the occupants to take advantage of daylight, breezes, views, and indoor-outdoor flow. The building is oriented to maximize solar and daylighting benefits. All energy is powered by the rooftop 47kW solar array, solar thermal, and geothermal wells. An interactive energy dashboard tracks real-time usage to optimize management and serves as an innovative and inspirational teaching tool.

Designing toward Living Building Challenge and LEED Platinum certification kept the team focused on creating a building that promotes occupant physical and psychological well-being. Hand in hand with sustainable design is the focus on life-cycle cost analysis and construction with durable materials requiring less maintenance. This philosophy was maintained throughout the project from design through post occupancy.

The post-occupancy period experienced some growing pains and difficulties with getting the systems to operate at peak efficiency, and lessons were learned that will inform decisions about the next phase of construction. But through team collaboration, trouble shooting, and monitoring of systems, the building was tweaked to run at peak capability and achieve its net-zero energy goals.

As part of their normal operations the Alice Ferguson Foundation encourages, promotes, and teaches responsible stewardship through composting all food scraps; recycling all waste that does not need to be landfilled; farming food and returning to the land resources that enrich the soil; and conserving energy by vigorously monitoring use.


Design Software: AutoCAD

Energy Simulation Software: eQUEST

Benchmarking Software / Methodology: EPA Portfolio Manager

Other Tools: Custom Water-use calculator, Custom Materials research calculator, Ecotect for daylight modeling, Solar Pathfinder, Green Footstep Carbon Footprint calculator

Did the project utilize Building Information Modeling (BIM) tools? Not on this project, Autodesk REVIT is being used for the Phase 2 building.


All materials, building components, and products installed into this building were scrutinized under the LBC lens for material toxicity, embodied carbon footprint, responsible harvesting and manufacturing, regionalism, and conservation and reuse. A major emphasis was placed on natural and durable materials, from the reclaimed solid wood floors, to the heavy timber wood trusses, and the reclaimed wood columns on the breezeway. Natural stone was used in the construction of the masonry fireplace, and a substantial standing seam metal roof was chosen for aesthetics, durability, and ease with which to mount the PV panels. Particular attention was paid to selecting materials with reduced maintenance, such as the prefinished cement fiberboard siding and the use of salvaged plastic/wood decking.

While some of the materials may have had a premium associated with them due to their character or lack of toxic ingredients, their life-cycle cost and environmental impacts were generally lower as they will last longer, require less maintenance, and can be recycled. For example, the metal roof with superior coating was more expensive than other roof options, but the product will last much longer than most roofing materials and will require very little maintenance. Its light weight and ease with which to attach PV panels reduced roof structure, eliminated other PV mounting components that would be necessary with other durable roofs like slate, which is another long-term roof material.

Similar to how the metal roof served a double duty as weather protection and PV mounting system, the design team tried to find other double duty uses for materials and systems. The kitchen was built on a concrete slab, which was stained, densified, and polished so that no additional flooring materials were needed in that room. The finished concrete floor was chosen as both a durable material with very little maintenance as well as for aesthetic reasons.

To meet Net-Zero Water targets, composting toilets and low-flow plumbing fixtures were selected to reduce overall usage by 94%. This allowed for the use of a grey water drip irrigation field. All storm water filters through a series of planted bioretention fields and rain gardens with native plantings. Lush plantings create soft edges around the angular building and are part of an aggressive stormwater management strategy that infiltrates 100% of the 10–year storm on-site.

Exterior of the Morris & Gwendolyn Cafritz Foundation Environmental Education Center

Lush plantings create soft edges around the angular building and are part of an aggressive stormwater management strategy that infiltrates 100% of the 10–year storm on-site.


Energy Use Description
The building is oriented to maximize solar and daylighting benefits. The building generates more energy than it uses via a rooftop 47kW solar array, solar thermal panels, and geothermal wells with very efficient heat pumps. An interactive energy dashboard tracks real-time usage to optimize management and serves as an innovative and inspirational teaching tool. The building enclosure is well insulated and air sealed, and all lighting is low wattage LED or fluorescent. Operable windows and ceiling fans were strategically placed to rely on low energy ventilation techniques to condition air on moderate days.

Exterior of the Morris & Gwendolyn Cafritz Foundation Environmental Education Center

The building nestles on the woodland edge and opens to the sun.

Annual Energy Use by Fuel
Electricity: 46,986 kWh
Total: 46,986 kWh

Annual Energy by End Use
Heating & Cooling: 16,489 kWh
Equipment & Site Lighting: 26,917 kWh
Lighting & Plug Load: 3,579 kWh

Annual On-Site Renewable Generation
PV: 54,377 kWh
Solar Thermal: not tracked

Peak Use
Peak Electricity Demand: Feb | 8,361 kWh
Connected Lighting Load: The values used in the energy modeling were calculated as follows (all values in W/ft²): Basement = 0.58; Common Area = 0.73; kitchen & corridor = 1.16; Pantry = 1.34; Bathrooms = 0.68; Storage = 0.70.

Data Sources and Reliability
Based on simulation? No
Based on utility bills? Yes
If yes, please list company or companies and dates of bills. SMECO (Southern Maryland Electric Cooperative); Dates of bills are 1/29/16, 2/26/16, 3/29/16, 4/28/16, 5/27/16, 6/28/16, 7/28/16, 8/26/16, 9/29/16, 10/28/16, 11/29/16, 12/29/16, 1/30/17

Comment on Data Sources and Reliability
A master meter and a PowerLogic Metering Commercial Edition Software and a Lucid dashboard system were used for public display.

After the first few months of energy tracking, the Lucid system was not matching the utility grade master meter. Working with Lucid, the public dashboard was tweaked to ensure it was reporting correctly and used weekly photographs of the utility grade meter for verification for the one-year performance period.


Indoor Environment Approach
On the interior, each of the 450 materials used were vetted to be free of the hundreds of chemicals of concern that are identified on the Living Building Challenge Red List. In keeping with the Owner's environmental mission and desired 'lodge' aesthetic, the wood flooring, ceiling treatment, and wainscoting were all milled from downed trees on-site, and exterior posts were salvaged from an Amish farm. All materials were very low VOC emitting or had zero VOC emittance. A construction IAQ management plan was implemented to: 1) protect workers on the site from undue health risks during construction; 2) reduce indoor air quality problems resulting from the construction process to sustain long term installer and occupant health and comfort; and 3) prevent residual problems with indoor air quality in the completed building. 100% outside air is provided to the interior of the building via ERV units for superior ventilation of occupied spaces. IAQ testing was conducted twice in the first year to prove that the indoor air quality goals were being achieved.


Project and Community Resilience Goals

It was important to the Alice Ferguson Foundation that the project could be resilient in the long-term as well as the short-term goals. The building needed to have systems that could weather changes in nature and the climate, as well as periods of intense and abundant use by visitors. The building was elevated above the potential water levels that could result from substantial rise in the Potomac River as predicted by climate change models. The rigorous stormwater management requirements of LBC will help the site survive extreme weather events without detrimental effects to the building or the surrounding landscape. The durable building materials and ease with which occupants can access and maneuver both within and around the building will help reduce congestion and areas of concentrated abuse.


The building and its surrounding pathways meet ADA accessibility requirements and the Cafritz Environmental Center is welcoming to the students, teachers and visitors who interact with the space. This wasn't always the case as the installation of the original specified compacted aggregate pathway material was not correctly implemented. Through difficult decision making and financial analysis, the Foundation opted for a traditional asphalt path to ensure easy access to all. This was a compromise that needed to be done so people could safely access the building, as there was not time to remove and repair the original pathway material. It was more important to have the building be accessible immediately so the Foundation could carry out its mission.

The energy and water goals of the project were fortunately met with no issues. The 47kW rooftop, grid-tied solar array generates more than 100% of required energy and the solar thermal panels generate hot water. Five 450 foot vertical geothermal wells provide energy for heating and cooling, while the high performance building envelope reduces energy needs for space conditioning. In 2017, these panels, along with geothermal wells and thick insulation, combined to generate 13% more electricity than was used while still providing electricity for site services such as a campus fire suppression system, water loops, and site lighting. Without these site related services, the building mounted PV array produced about 220% of the building's first year of electricity use. This excess energy, generated from the sun, and enhanced and made more efficient through our geothermal system, was sent back into the grid. At the same time, composting toilets eliminate the need for toilet flushing, saving 3–5 gallons per flush and other waste is captured and upcycled to topsoil in Clivus composting toilets.

Finding the technical pathway to a beautiful Net Zero Energy and Net Zero Water building was challenging, but relatively easy compared to identifying and sourcing the red-list-free, non-toxic, locally produced materials used in the building. Perhaps the greatest creativity was required in overcoming the regulatory, policy and supply barriers to building the project. It took years of education, advocacy and work with local and state agencies and utilities to garner permission to deploy technical solutions that allow the building to meet the requirements of LBC. The project team invested enormous energy in research and advocacy to identify—and in some cases to convince manufacturers to permanently change—products that are free from environmental toxins on the red list.

Net Zero Energy, Water and Waste Diagram

Net Zero Energy, Water and Waste Diagram. After one year of operations, the project is net-positive for energy and has a closed-loop water system.


The strategies that were selected for this project were evaluated through several methods and lenses, from LEED certification through Living Building Challenge certification. The latter of these rating systems required a year of data collection to prove the project had achieved its goals. After collecting and analyzing 12 months of operating data, the Cafritz Environmental Center verified its Net Zero Energy performance and net zero water performance, among other measures of site sustainability, equity, health, and beauty.

Closed loop water system. Water in = water out.

Closed loop water system. Water in = water out.

Design Trade-Offs and Interactions

This can best be described through a few examples. One is the pathway example provided under the lessons learned section where a conventional material was selected over one with less environmental impact due to safety and accessibility concerns. Another example would be the composting (nutrient recycling) toilets. They are an excellent way to manage waste and responsible replenish the earth, but it comes with an on-site energy penalty. The composting units need to be continuously ventilated, which means there is continual fan energy being consumed; arguably, this is still far less energy than needed to convey and treat water off-site.

Postive and Negative Aspects of the Process

This project was successful because of the drive and determination of the team as a whole. Where one individual or team player fell short, another would step in and fulfill their role. The commitment of the design team, the contractors, and members of the Foundation staff to not lose site of the end goal even when times got tough was instrumental in the success of this project. Permitting challenges for innovative technologies and documentation of the Materials Petal were among the more difficult and time consuming obstacles, but perseverance prevailed.

How Building Materials, Systems and Product Seclection Addressed the Design Objectives, Goals, and Strategies

The biggest goal for the project was to push the boundaries of sustainable design so they project could inspire others to develop in a way that responds to global climate challenges while also providing lasting impact to visitors and local communities. Inherent to this goal was reducing material toxicity, reducing operating energy, providing on-site renewable energy production, and managing storm water and waste water on-site. The biggest hurdle was arguably eliminating all harmful chemicals on ILFI's "Red List", especially considering that each product may be comprised of hundreds of individual chemicals. But through careful material selection and research, the goal was achieved. Additionally, the materials and systems that helped create a super insulated enclosure with lower energy demanding equipment allowed the on-site renewable energy system to be reduced in size.

How the Project Addressed Existing Site Conditions and Context, Including the Surrounding Community

As an environment education center the Alice Ferguson Foundation (AFF) relies heavily on landscape to demonstrate their philosophical values and support the educational curriculum. Working within these constructs, the team developed a site design that supports and improves upon the surrounding analog habitat communities. The proposed design strikes a balance between supporting AFF's educational programs through strategic landscape interventions that offer intimate access and/or views to flora and fauna, and restoring the degraded habitat margins of the site. The rich palette of native and adapted plant species interweave with the central circulation spine of the site and adjacent storm water management system. These species were selected with the client based on criteria such as growth requirements, habitat value, educational benefit, aesthetics, and resistance to deer browse. This systematic approach not only immerses visitors in a network of bio-diverse habitat islands, but encourages the reintroduction of fauna that may currently be absent from the site. The perimeter of the site has been reinforced with mixed story plantings of canopy and understory vegetation to provide immediate biodiversity and build a seed banks for the long term inoculation of the existing woodland.

Synergies that Resulted from the Strategies Implemented

This project aimed to be a poem of synergies, from the relationships between the various buildings of the new campus, to the interaction between the natural elements and the site. The Cafritz Environmental Center harnesses the energy of the sun to produce electricity and hot water, which allows the building to carry out its functions. The building in turn takes its waste in the form of black and grey water, and returns it to the earth to recharge the aquifer and add nutrients to the soil. If the building is being operated efficiently it will produce energy that can be used by other buildings on campus, and the support of farming practices with compost provides a resource to the Foundation.

How the Performance of the Building was Measured or Evaluated

The building's performance is measured in terms of the structure's Net Zero Energy, Net Zero Water, carbon neutral, and non-toxic construction material requirements of the Living Building Challenge, as well as its ability to serve the client, student, and community populations. To date, it has achieved full Living Building Challenge certification and is the highest LEED scoring commercial building in the state of Maryland and in the COG jurisdictional area, achieving 100% of the available points in the LEED Energy & Atmosphere and Water Efficiency categories.

How the Owner/Client and Community Benefited

The Foundation currently operates multiple educational programs focused on stewardship for people of all ages including students (Pre-K to 12), teachers, and even National Park Service Rangers. With the construction of this new building the foundation will be able to educate more people on the need and benefits of being environmentally conscious. In addition the Foundation also had a number of environmental outreach programs that they like to call "Environmental Action". These programs include, 'Trash Free Potomac Watershed Initiative', 'Trash Free Schools Project', and 'Student Action'. The Cafritz Environmental Center has become the centerpiece of the Alice Ferguson Foundation's environmental education programs.



  • 2017 Living Building Challenge (full certification)—International Living Future Institute
  • 2015 LEED Platinum Certification—Leadership in Energy and Environmental Design


  • 2018 Professional Bronze Award for Design–Society of American Registered Architects
  • 2018 Beyond Green™ Award of Merit–National Institute of Building Sciences
  • 2015 Best Real Estate Deals–Washington Business Journal
  • 2007 Demonstrated Leadership In The Living Building Challenge On The Boards–U.S. Green Building Council


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