In the last couple of months, New York has announced statewide bills and regulations to help maintain the health and safety of our communities and transition to cleaner sources of energy. At LaBella, we’ve assembled a team of experts who stay on top of the latest news and play an active role in implementing them into our clients’ designs and everyday operations. It’s all part of our job in building a better future.
Cory Stamp, EPA Lead Risk Assessor in LaBella’s Regulated Building Materials group, reports on the state’s recent emergency regulation on the testing for lead contamination in schools’ water systems. Schools can expect to test more potable water outlets like drinking fountains and sinks more frequently to improve water infrastructure and protect the health of students, faculty, and staff. Also in this issue, Electrical Engineers Darren Pieters and Jim Barnum, EIT explore some of the hurdles anticipated after New York State announced the switch to completely electric bus fleets by 2035.
Want to see your idea in the next issue of In Session? We would love to hear more about it. Submit your topic to insession@labellapc.com.
LaBella proudly announces that two of our technical staff members are now WELL AP certified! Project Architect Jessica Kruse, AIA (pictured left) and Interior Designer Danielle Lewis, CID (pictured right) recently passed their WELL AP certification exams and are the first to do so in our organization.
Unlike LEED, WELL focuses on spaces that advance human health and well-being, looking at how built environments can support the physical and mental health of a space’s occupants. Both architecture and interior design are rooted in designing for the health, safety, and welfare of the public. Since the global pandemic, there has been greater societal emphasis on well-being.
WELL’s 10 basic concepts include strategic recommendations regarding air, water, nourishment, light, movement, thermal comfort, sound, materials, mind, community, and innovation. Buildings can receive a Bronze through Platinum rating, similar to the LEED rating scale.
Having employees with this certification aligns with our core value of “seeking growth and embracing change”. By becoming WELL AP certified, our staff are amongst the early adopters of this newer standard and look forward to sharing their knowledge with our clients.
LaBella recently received two awards from the American Sports Builders Association (ASBA) Awards Committee and Board of Directors. Webster Schroeder High School was recognized as a winner in the Multi Field category and the Public Service Leadership Academy at Fowler was recognized as a winner in the Single Field category. Held in Palm Springs, California in early December, the annual awards program supports ASBA’s goal of promoting excellence in sports facility construction and design.
The fields at Webster Schroeder were installed as part of Webster CSD’s 2018 Capital Improvement Project. The athletic portion of the project included a new 4.5acre, multi-purpose turf baseball/ softball/practice field, track, and sodded natural grass field. Athletic amenities included backstops, bullpens, batting cages, dugouts, bleachers, scoreboards, ball netting, portable outfield fencing, and stadium lighting. An entrance area to the field complex was reconstructed consisting of concrete, landscaping, a new storage building, and restroom area. The track facility was upgraded from a cinder track to an asphalt track with rubberized surfacing. Multiple track events were upgraded, including long jump, triple jump, high jump, steeplechase, pole vault, shotput, discus, and hammer throw. A large grandstand and press box were installed to improve the field seating capacity and provide live event broadcast capabilities. Stadium lighting was installed to allow extended hours of play. Additionally, a new natural grass sod field was constructed on the interior of the track.
The field at the Public Service Leadership Academy at Fowler was in a floodplain, discharged
to an impaired watershed, located within an urban area and landlocked between existing developments and streets. There was a limited footprint in which to develop a track and field facility. Additionally, varying depths of peat were found in thicknesses from 0 to 17 inches during geotechnical investigation. This project is unique in its construction below the surface. The likelihood of differential settlement was a concern due to the varying
soil profiles. To keep the track intolerance over a design life of 15 years, several options were explored. Ultimately, the site was designed with deep timber pile foundations that would bear the load on stable native soil below the peat. A concrete “floor slab” was constructed over the piles to support both the track and the field.
Congratulations to our clients and design teams!
In April 2022, the New York State Legislature passed a budget to transition school bus fleets to 100% electric vehicles (EV) by 2035. The legislation also requires the purchase of new school buses to be completely electric starting in 2027.
With roughly 50,000 school buses across New York State, the legislation poses challenges for school districts to consider when planning for such a transition, including fleet distances, charging times, and reliability. School districts will need to implement electric charging stations, identify potential solar applications, and implement significant utility infrastructure upgrades to transition a large electric bus fleet.
To start, school districts will need to perform a detailed
analysis of existing bus fleets for a successful implementation of EV buses. An understanding of the shortest, longest, and average distance routes will enable districts to complete routes reliably and year-round.
Fortunately, there are funding opportunities to assist in these planning efforts, especially for schools in disadvantaged areas. Funding for implementation is limited at this time but anticipated to increase in 2023.
There are some key characteristics of EV that should be understood, to varying degrees, by all stakeholders involved in the discussion.
How far can an EV bus go? This is not necessarily an easy question to answer as there are several factors that can impact the manufacturer-labeled range. For example, range can be affected by driving speeds (highway vs. neighborhood), the number of passengers, and other driving practices.
Perhaps the biggest factor impacting expected range in Upstate NY is cold weather. Unlike internal combustion vehicles, EV bus engines don’t use high temperature and pressure gases to apply direct force to the engine. All of the energy that goes into heating an EV bus is effectively “taken” from what would have been used to move the bus. It is common to see a 30-40% decrease in range on the coldest of days in this
area. This does not include idling at student pick-up spots and bus loops, which would further decrease the range. There are additional heat systems, such as diesel heaters, which can be included as a backup for very cold climates; however, this still continues the use of traditional fuels and pollution, and as such, would not qualify for state or federal incentives. Due to this, this additional cost would not be covered by current state or federal incentives.
With this in mind, school districts should perform a pilot program on a handful of buses before changing over their fleet. This will allow conditions and the impact of routes, drivers, and seasonality to be evaluated. The EPA and NYSERDA have programs to purchase a few buses via a grant or voucher program, respectively.
EV charging requirements depend entirely on real world usage. When determining charging station needs in Upstate NY, worst case numbers should be used from January to February for a given route. Ideally, a bus would be plugged in at the end of the day, charged overnight, and be ready to go in the morning. For some routes on cold days, additional charging may be needed during the day between morning and afternoon runs.
Districts will have the choice between installing Level 2 or the more powerful Level 3 charging stations. Level 3 stations can charge about three times faster than Level 2 stations; however, this will have a significantly higher install cost as well as reduce the overall quantity of charging stations able to be installed at a given location. This topic is discussed in further detail, at right.
EV generally have lower maintenance costs when
compared to traditional internal combustion vehicles. As a reminder, this cost savings should be estimated by the districts and included into the financial model along with fuel savings and electrical costs.
School districts should be aware that EV buses are an emerging product in the transport industry with a very small market share. Here in the US, two of the larger bus manufacturers (Bluebird and Thomas) have sold and delivered only a combined 1,000 EV buses as of September 2022.
These numbers are not meant to discourage–the technology itself is stable and reliable. However, it does show that the necessary utility infrastructure needed to power these vehicles is unlikely to be in place. The best way to begin to evaluate infrastructure readiness is to contact your utility provider and begin a fleet assessment. Not only will this help districts evaluate their needs, but it will help utility companies as they plan future upgrade priorities.
EV charging stations are classified in three categories: Level 1, Level 2 and Level 3.
Level 1 charging stations draw power from a cord and plug connection to a typical, everyday receptacle (120V/1 phase) for hybrid or EV automobiles. This can be considered trickle charging and is not a recommended option due to excessively long charging times (over 24 hours).
Level 2 charging stations are hardwired to standard electric power panels found in school settings. For fleet applications a typical charging rate would be 12 kW, which would allow for overnight charging of the buses (time to charge: 10-12
hours for a large bus). Level 2 currently only comes in 208-240 V, single or dual port connection, approximately 20-80 Amps. The cost ranges between $1,000 to $10,000 for the unit, depending on kW selected and does not include wiring or installation. These have a one year to five year warranty depending on the manufacturer and extended warranty purchases available.
Level 3 charging stations (also called DC fast chargers) require a 480V/3 phase utility service, typical for large buildings and industrial facilities. Existing transportation facilities at school districts are not likely to have this service currently installed. There are a wide range of charging options and configurations available at this level. Standard offerings for fleet applications provide for 30-200 kW charging rates, 100 up to 1,600 Amps, and 3-4 hours to charge a large bus. The cost ranges between $5,000 to $100,000 for the unit, depending on the kW of the unit. Again, this does not include wiring or installation. These have a one year to five year warranty depending on the manufacturer and extended warranty purchases available.
As part of the planning process, a decision needs to be made as to how many Level 2 and Level 3 charging stations to install. In a perfect world, there would be no need to decide between installing Level 2 and Level 3 charging stations as all Level 3 stations would be installed. However, cost and electric service availability are the two driving factors that make this prohibitive. The Level 3 chargers are both significantly more expensive to purchase and orders of magnitude more expensive to install. Keep in mind, Level 2 chargers currently do not offer 480 V, thus driving up costs for step-down transformers and additional gear, and larger feeder sizes.
The most ideal scenario is a small bank of Level 3 chargers
allocated for routes requiring multiple charges a day, with the remainder of the fleet charged from Level 2 chargers overnight—a combination that allows for cost savings and reliable operations.
Providing enough electricity to power the fleet of EV buses and their charging stations is the most challenging technical hurdle to implementing a fleet of EV buses. Not only will the district transportation facility electrical service require replacement or a separate service altogether, there will also be significant modifications needed on the part of the utility company to provide the amount of electricity needed to power a mid-to-large sized fleet.
As an example, a local school district with a fleet of 190 EV buses would require approximately a 6,000A 480V/3 phase service (Level 2 charging stations only) with sequential charging. If four Level 3 charging stations were installed, about 20 Level 2 stations would have to be removed to accommodate: 170 Level 2 stations and four Level 3 stations for the same 6,000A service. The utility company may not be able to provide this type of power without upgrades to substations or providing power distribution from a different source altogether, if available.
As a means of comparison, many of the local large high school buildings have services that are a third to half this size (1,000A, 480V/3 phase for example). On top of that, the typical active daytime loading seen at one of these facilities is less than half of its service size. The EV bus charging yard would max out its service rating for eight hours every evening. So, it would draw five to ten times the electricity from the grid during typical use,
compared to that of a large high school facility.
This is a significant load on the local utility distribution system. A new line may need to be run back to the nearest substation, which may also have to be upgraded to accommodate the additional load with up-sizing the MV service voltage to 34.5 kV, 46 kV, or 69 kV. Typically, these are currently at 5 kV to 15 kV.
A new utility line can be expected to cost, conservatively, hundreds of thousands of dollars, depending on proximity to the substation and existing pole configurations. Substation modifications, if needed, could cost several million dollars. The utility company will (most likely) push these costs onto the school district as a customer-funded project.
Revising the site locations of the transportation facilities to be near a large utility substation may be a feasible option to reduce these costs. This type of opportunity would be evaluated district by district.
It’s possible that integrating solar into your district’s infrastructure can offset some utility energy costs. As with EV buses, there are several concepts that are critical to successful integration. Solar power can be used to put power back into the grid to help offset power demand and costs; it is not directly used to power up the buses. Buses would need to be charged overnight when solar power is not being generated.
EV school buses and solar power generation do not play to each other’s strengths. During the winter months, solar power production is at the lowest point of the year while most solar production occurs during the summer when school is out. Conversely, the highest demand
for EV usage is during those same low-production winter months. This means that the utility connection cannot be reduced in size no matter how much solar power generation is put in place.
With that being said, solar power can be used to help offset the monthly cost of electricity, as power generated during the summer months can be converted to credits by the utility and used during the school year by districts.
It is estimated that one bus would need about 50 solar panels, or 3,000 square feet of panels, to be powered during the school year. This assumes the bus is only used 180 days a year and that the solar modules produce power all year long, which means approximately 15-19 buses can be powered from a solar array the size of a football field. Costs would range from $2.50 to $3.50 per watt and $70,000 to $100,000 per bus for this type and scale of solar installation.
Deciding how much solar power generation to provide, or whether to provide it at all, can be a complex decision. Technically, both EV bus integration and solar power generation are very scalable in terms of deployment. They can be done incrementally, together, or separately and on independent project timelines.
It is important to keep these factors in mind when assessing energy evaluations for your district. Additionally, funding is available through Clean Green Schools and Flextech to help with the planning efforts, including the electrification of your bus fleet.
To meet the NY State requirements for transitioning district school bus fleets to EV buses, several technical issues
should be addressed during the planning phase.
The biggest technical barrier to implementation is the electric utility company. Early outreach from the district, in partnership with an engineering firm, to a local utility company is strongly recommended. The possible utility costs will necessitate cooperative design between the engineering firm, utility, and school district.
In parallel, a detailed evaluation of the existing fleet routes should be performed to estimate a reliable fleet replacement and match expected usage to EV buses, charging stations and/or solar power generation. Ideally, several scenarios would be provided with varying quantities of Level 2 and Level 3 charging stations.
It is also highly recommended to implement a year-long pilot program with a handful of buses to provide feedback to the engineers designing the system. This allows for real-world conditions to be accounted for, as well as strategies such as opportunity charging and shared charging stations. The Make Ready program, an utility incentive for EV charging infrastructure, may be a great fit
to help your district with funding and technical guidance on adding chargers.
Solar power generation is a possible supplement to the charging station infrastructure. Due to a mismatch of energy supply (peak solar generation in summer) and EV bus demand (few summer routes and harsh winters), it is not an option for offsetting utility interconnection and supply costs but could be a worthwhile addition to your district’s energy upgrades in the near future.
School districts should discuss how they want to handle travel to and from out-of-town extracurricular events for the students in the event they fully transition to EV. Districts should partner to ensure chargers are available for visiting teams or groups from other districts participating in events such as clubs or athletics. There are likely to be scenarios where EV buses are not viable options due to trip length. Potential options include bus rental and a possible exemption from the state for use of traditional internal combustion vehicles for these situations.
The use of buses in emergency situations should also be studied. An on-site standby generator(s)
will be needed to power the charging stations, which means significant additional costs and landscape to accommodate emergency power/generators for the electric buses.
Phased implementation of the EV bus transition is recommended. This provides the flexibility needed to reliably provide transportation services to students, year-round. It also allows for cost-effective deployment and balancing EV and traditional internal combustion vehicles usage as needed. Furthermore, if the policy or available technology were to change in the future, the district will be in a good position to meet new requirements or technology.
In summary, transitioning bus fleets to EVs will require a number of parties to work together to clear technological and budgetary hurdles. It’s not too early to start evaluating your fleet and routes and looking at your electric service options. With utility expertise in house, LaBella can help our districts navigate the road to EV buses.
As of press time, NYS Governor Kathy Hochul announced $23 Million in funding and awards for transportation electrification initiatives (see QR code below for more details). We will bring you additional information as this continues to evolve and develop. If you have any questions on what this means for your district, contact us at insession@labellapc.com.
Last month, members of our K-12 and Higher Education studios attended the 2022 EDspaces conference in Portland, Oregon. This annual conference highlights the work of experts in educational design, learning environment furniture solutions, and teaching methodologies through local facility tours, education sessions, and showroom exhibits. Here are some of the highlights from our experience this year.
STEAM Education (Science, Technology, Engineering, Art, and Mathematics) is a pedagogical movement that has surpassed “trendy” to become a critical component of school curricula from early childhood through post-secondary education. In STEAM classroom environments, project-based learning prepares students for an ever-changing world beyond the classroom by teaching critical thinking, collaboration, and experimental skills. At the 2019 conference, many furniture solutions and discussions centered around the makerspace component of STEAM programs. Three years later we’ve seen makerspaces go beyond standalone rooms with project-based learning concepts becoming commonplace within other school settings. At East Irondequoit Central School District’s Helendale Road Primary School Library, which was completed earlier this year, the space encourages student play and experimentation within the larger context of the media center.
This year’s conference saw a notable shift toward the inclusion of Esports (competitive video gaming) spaces within the school STEAM environments. Esports programs at the university
level have become increasingly popular as more and more college programs offer majors and scholarships in the field. Programs like these are starting to be implemented in the K-12 market as educators embrace the multi-disciplinary concept. In his presentation on Esports spaces, Researcher Greg Nelson from School Outfitters detailed how these programs touch all aspects of STEAM as students learn about technology, computer programming, game design, communication, and teambuilding skills.
Esports will continue to grow, particularly within the secondary school environment. Many schools already include extensive STEAM programming as well as in-house broadcasting for school television or radio shows. Esports can serve as a bridge between the two to create a real-world simulation of the profession.
Just as in 2019, the EDspaces showroom floor was saturated with biophilic design elements referencing and replicating nature in the interior built environment. Many furniture systems incorporated real or preserved plants in space dividers and natural textures like wood were used everywhere from temporary partitions to early childhood play furniture. In addition, several EDsessions focused on the connection between nature and student health and well-being, a concept that has been backed up by evidence-based design as well as certification programs like the WELL Building Standard.
The concept of student wellbeing has become increasingly important as a wellness report
by the ACLU in 2022 found that self-reported ratings of “mental wellness” have decreased since the pandemic. Another study completed in 2021 by the American College Health Association indicated that between 31% and 38% of college students felt excessive stress and anxiety. Even before 2020, many schools implemented emotional intelligence programs in their curricula, clearly indicating a shift toward bolstering student mental health. Beyond the inclusion of nature, other strategies to promote a sense of well-being included creating a strong community identity through personalization, including plenty of access to natural light, views, and ventilation, incorporating opportunities for movement through active furniture or fitness programming, and designing zoned spaces for collaboration, quiet work, and self-reflection.
Student and staff mental health is critical for the success of teaching and learning as occupants who are chronically stressed or anxious will not be ready to learn. Designing for well-being will become a key indicator of educational design success and help students to feel connected
to their larger school community in a meaningful way.
“Not everything that is faced can be changed, but nothing can be changed until it is faced.” These are the words of American novelist James Baldwin and one of the opening thoughts in a presentation by Katrina Ruiz, Dr. Joe Morelock, and Anne Erwin, architects and educators from the Portland, Oregon area. Over the past several years, diversity, equity, and inclusion (DEI) initiatives have become a core tenant of many organizations’ values and strategic planning initiatives as society has focused on injustices and inherent biases facing marginalized groups. In their presentation, the architects discussed a process called “Equity Commissioning,” which is a process of identifying, prioritizing, and evaluating the successful implementation of equity-based design elements in a project.
Educators have been at the forefront of many of these conversations as the student body represents a wide variety of racial and ethnic groups, LGTBQ+ communities, socio-economic backgrounds, and more. However, designing for these groups in meaningful ways has often been overlooked or difficult to achieve. This year’s conference challenged facility planners and involved project stakeholders at all levels and backgrounds to think of the ties between inequality and the
built environment and to consider how planning decisions impact the most marginalized occupants, and how design elements may be biased toward majority groups.
One simple design example throughout many of the Portland Public School System buildings was the pervasive use of inclusive restrooms. To provide comfortable facilities for people of all gender identities, single-stall toilet rooms are oriented along a shared handwashing “corridor” that removes expectations or stressors associated with entering binary-gendered spaces. Considerations and difficult discussions on inequalities like these bring important issues to light and ultimately improve the user experience for all building occupants.
DEI initiatives are an incredibly important topic in today’s society. As populations continue to evolve, educators and school planners need to be open to big ideas and difficult conversations to ensure their spaces are truly responding to the needs of their diverse populations.
As a natural part of the design process, architects and interior designers solicit feedback from end users early in the conception of a project to identify the needs, wants, and goals of our clients. LaBella excels at engaging the school and surrounding community during pre-design to help ensure the spaces we
design respond to each client specifically and do not fall into a “one size fits all” approach.
In addition to pre-design feedback, post-occupancy evaluations have gained traction, especially in educational design. A post-occupancy evaluation (POE) is a systemic process of evaluating buildings on building operation and occupant satisfaction through performance testing, observation, surveys, focus groups, and other data collection methods. This process serves to test whether a design met the functional goals established in pre-design conversations, what impact design solutions to those goals made, and whether they were the right goals in the first place. An effort toward continuous improvement, POEs should be used to document and capture these changes, for worse and for better.
POEs will become more commonplace and serve as a tool for education professionals and designers to learn from past projects. POEs will not only bring to light decisions that were successful or unsuccessful, but also highlight the changing ways in which students and staff use space in innovative ways that may not have been thought of before.
As usual, EDspaces provided an engaging variety of content that our team looks forward to implementing in our work. Let us know your thoughts and how we can share this knowledge with your district.
On September 6, 2016, the New York State Department of Health (NYSDOH) introduced an emergency regulation entitled, “Lead Testing in School Drinking Water: 10 NYCRR Subpart 67-4” (Subpart 67-4).
The first of its kind in the nation, this law requires public school systems to test potable water outlets for lead contamination and remediate any outlets with lead levels above 15 micrograms per liter (μg/L). After reviewing the past six years’ worth of data from across the state, the State Assembly has recognized the need for stricter regulations.
Senate Bill S2122A was signed into law on December 22, 2021, and will go into effect on the same date this year. In short, schools can expect to test more potable water outlets (drinking fountains, sinks, etc.) more frequently, and with a significantly reduced activity level.
The new Lead in Drinking Water (LIDW) bill carries some substantial changes, outlined below.
• The lead action level has been reduced to 5 μg/L. Any potable water outlet with lead levels above 5 μg/L will need to be made unavailable to staff and students and included in the district’s remediation plan. Outlets can only be made usable
again once post-remediation sampling of the outlet delivers test results that are below the lead action level.
• When signed in 2016, the original law required schools to test their outlets every five years. Starting in December 2022, schools will need to test their outlets every three years.
• Under the current version of the law, certain buildings are exempt from sampling. If the building was constructed after 2014 or a NYS professional engineer or architect certified the building to be “lead-free”, no sampling was required. This exemption has been omitted from the new bill; every school building in the district will need to be tested, even if considered to be “lead-free.”
• As before, any outlet that is found to be leadcontaminated will need to be prohibited from use for employees and students immediately. The district will then need to supply adequate amounts of drinking and/or cooking water until test results indicate that the lead levels are at or below the action level. Senate Bill S2122A stipulates that this adequate supply of potable water must be free to all building occupants.
• Within 10 business days of the receipt of laboratory reports, districts must notify all staff, parents, and guardians of any exceedances. In previous correspondence with the DOH, LaBella confirmed that posting on the school website or social media does not constitute as a written notification. Bill S2122A clarifies this by eliminating this option. Physical written notification of exceedances must be distributed to all staff and persons in parental relation to students.
• Within six weeks of the
receipt of laboratory reports, districts must post the test results of all testing and all remediation actions taken. The new bill adds a line clarifying that laboratory reports must be included. Reports may be posted on the district website and must remain for the entirety of the compliance period.
• The new bill does come with new instructions for reimbursement. Any necessary remediation shall be “…fully reimbursable from funds appropriated through the department on environmental conservation for clean water infrastructure
projects.” While details have not been provided, the NYS Environmental Facilities Corporation (EFC) has a Drinking Water State Revolving Fund (DWSRF) that has been used by school districts in the past. LaBella will continue to collaborate with districts to identify reimbursement or funding options.
• The rest of the law is to remain largely the same. The new bill does not change the definition of what type of outlets are applicable. As under the old law, the district has the responsibility to determine which of the outlets present on school property are “applicable outlets” and meet the requirements for sampling.
Examples of applicable water outlets as defined by the DOH include the following:
• Drinking fountains
• Sinks found in classrooms, kitchens, bathrooms, family/ consumer sciences rooms, teacher’s lounges, and nurse’s offices
• Coffee makers
• Ice machines
• Combination bottle filler and fountain
• Athletic field outlets
• Any outlet that could be potentially used for drinking, cooking, or food prep
As before, an outlet may be deemed non-applicable and not subject to testing if it is in a room or office that is not used by students AND does not provide drinking or cooking water. This
includes dishwashing sinks, bus garages, and outlets in rooms that don’t allow drinking like science labs or art classrooms. Also exempt from testing are tempered outlets where there are no separate controls for the hot and cold water supplies. In their remediation plans, schools must include strategies for ensuring non-applicable outlets are not used for drinking or cooking.
Districts should expect to increase the budget for their sampling events significantly. All sampled outlets are now subject to the new action level. With the action level reduced by two-thirds, more outlets will need to be remediated and then resampled. In one school district that recently completed sampling, LaBella found 19.9% of sampled outlets were between the old action level of 15 μg/L and the new action level of 5 μg/L. These outlets will need to be remediated and then resampled, and all outlets will need to be sampled again in three years. Also, any buildings previously deemed “lead-free” will now need to be tested. All these factors will impact already stretched school budgets.
LaBella’s Regulated Building Materials Group has worked with public school districts both large and small. Our experience has shown that the districts that have a LIDW plan, including identification of applicable outlets before sampling events and familiarity with their plumbing systems, tend to be the most prepared to respond to any problems. If you have any questions regarding Senate Bill S2122A or are looking for assistance with your LIDW plan, please reach out to us.
