Worcester Water Filtration Plant (II)
January 21, 2009
Environmental Science students visit the city’s water filtration plant in Holden, MA. Pictures above display i) the role that computers play in monitoring and managing each treatment step, ii) plant manager Bob Hoyt fielding a question from upper school science teacher ,Paul Elkins – in the room for coagulation (fast mixing of aluminum sulfate and cationic polymer binds to debris, forming flocs, which after going through slow mixing, or flocculation, will be filtered out by the top layer of the direct filtration beds (comprised of 5 feet coal, 1 foot sand, 1 foot gravel) and de-ozonation (excess ozone needs to be converted back to O2 before being released outside)- and iii) students peering over the direct filtration beds (filtering water at a rate of about 6 gallons/sf/minute). Typically, the plant reaches it annual maximum during the summer, with 32+ MGD, well below its maximum capacity of 50 +MGD. If and when a water main breaks, the plant will have to compensate for the water pressure drop and lost water by increasing filtration rates by a few MGD. The city is working to mitigate the contamination threat from “cross connections” which is when non-potable water (contaminated with pesticides, chlorine, industrial materials, etc.) back-flows into the water distribution systems due to negative pressure. For more information click on the Water page above and previous water post
Alta Vista Buffalo Farm
November 25, 2008
Coopers Hilltop Dairy Farm Revisited
November 25, 2008
Nicewicz Farm
November 25, 2008
- Apple Maggots (IPM)
- Peach Tree
- Lay of the Land
Buffone Garden Day 2
September 23, 2008
WA Environmental Science students spent a second class period harvesting crops and preparing the local Buffone Garden for winter. There was a surprised siting of a hawk atop of Rader (photo below)
Creating urban gardens for food production is a potentially transformative act in terms of community building, broad and dynamic virtues of cultivating growth, decreasing carbon emissions and run-off pollution, and biological/ecological field study opportunities, among other benefits.
Neighborhood Garden Work
September 17, 2008
Whitin Mill – Greening of the Blackstone
May 8, 2008
- Plaza
- Dennis Rice
- Pagoda
- Tulip wood Soundboards
- Old water turbine
- Mumford River
- Art Gallery
- Whitin Mill
The Whitin Mill (built in 1826) rising up along the Mumford river- tributary to the 45 mile long Blackstone River-has recently been transformed, along with three adjacent buildings including an old forge with an intact foundation from 1772, through a five year sustainable renovation project led by Alternatives. True to the spirit of innovation that drove the Whitin Mill to become the worlds leader in textile machinery manufacturing (cotton spinning rings produced through the 1970’s) Alternatives has delievered a green, “social capital” rich complex comprised of a theater, offices, art studio space, apartments, and a restaurant. 100% of HVAC demand will come from 5 geothermal wells dug down 1500 feet to 52 degree F water, saving $60,000/year in heating/cooling costs. Power for the buildings will be provided by solar and hydro power. 5% of the property’s 240,000 kW-hr annual demand will come from 32 solar panels (12,000 kW-hrs a year) while the remaining 80% will come from a soon to be completed 37 kW hydro turbine (320 kW-hrs/year) which will sell power at night back to the power company translating in savings of over $30,000 from unpaid utility bills and an additional $12,000+ from selling back to the grid.
95 % of the materials from the site were recycled, including the use of a diseased tulip tree that was cut and boarded for use as sound control panels in the theater. Built wood parts were routinely reused for flooring and the deck of the plaza is made from recycled plastic-wood composite. Take a tour yourself, it is an inspired work for an inspiring future, especially for the slumbering Blackstone Valley.
For more information go to http://www.telegram.com/article/20080422/NEWS/804220498
and http://www.alternativesnet.org/whitin_mill_restoration.asp
Electronic Recycling Plant in Worcester,MA
May 7, 2008
Andrew McManus, METECH GENERAL MANGER, displays a curcuit board.
The WA Environmental Science classes travelled about a mile from school, just across the start of the Blackstone River along route 146, to the Metech International facility (www.metech-arm.com) in order to learn about the scale (1,000,000 lbs/month) and 3 tier process of recycling electronic waste (reuse, recovery, and reclamation) at Metech.
In 2005, 20-50 million tons of “e-srap” (anything with a chord) were produced in worldwide. In 2007 the US e-scrapped 500 million personal computers. Metech processes electronic equipment for metal reclamation (gold, platinum, silver to copper and aluminum, etc.), while sending off plastics, cardboard, and toxic heavy metals such cadmium and mercury for recycling and/or hazardous waste handling.
- misc electronic
- Plastic wrap
- Shredded Copper.
- Reclaimed copper
- Shredded Curcuit Board
- Silverbars
- Shredder
- stereo equipment
- Lead Acid Battery
- Magnetic Recycler
- curcuit board
- cellphones
For Flow Charts of recycling process click below:
material-flow-no-animation-no-1
The Nuclear Option
March 6, 2008
Worcester Academy gets approximately 27% – as compared to a 20% national average- of its electricity from nuclear energy: fission of 2-3% enriched Uranium-235.
The benefits of nuclear are the enormous amount of energy that fissionable U-235 releases. One gram of U-235 (depending on enrichment level) produce the same amount of heat energy as burning 6,000 pounds of coal when used to heat water into steam which in turn spins a turbine to generate electricity. Further, there are no greenhouse gas emissions, electricity can be produced cheaply (though this could be argued against given special insurance policies for nuclear and unsettled costs for nuclear waste management), and in theory nuclear fuel can be reprocessed many times over. Capacity of New England nuclear reactor plants (see photo) is as follows:
Location- Name- Capacity
Maine- Wiscasett Maine Yankee (closed) 850 MW
CT- Haddam Neck Plant (closed) 590 MW
Millstone Nuclear Niantic Bay, Waterford (unit
closed) 652 MW
Unit 2 900MW
Unit 3 1200 MW
VT- Vermont Yankee, Vernon, VT 540 MW
NH- Seabrook Nuclear Station, Seabrook, NH 1200 MW*
MA- Yankee Nuclear, Rowe, MA (closed) 185 MW*
Plymouth Station, Plymouth, MA 655MW
Approximate Total: 4,500 MW (operating)
However, reprocessing fuel is dangerous (particularly if spent plutonium is involved, which can be isolated easily using chemical means to make a bomb but is rare in the US for energy production) and there are currently no operating reprocessing plants in the United States. Complications with nuclear energy also include managing nuclear waste which contains lethal and carcinogenic radioactive materials with half lives ranging from a few dats to 10’s of 1,000’s of years [Pu-239:1/2 life=24,360 years: alpha emissions, cocentrates in bones/lings, Sr-90: 1/2 life= 28.8 years: beta emissions: concentrates in bone and teeth, I-131: 1/2 life=8days: beta and gamma: thyroid, Cs-137:1/2life=30 years: beta and gamma: whole body] The many waste products of nuclear fission, such as these, must be handled without mistake and need to be stored securely for 100,000’s of years. Current solutions have included underground storage in geological stable caves. Currently there are over 50,000 metric tons of nuclear waste in the U.S., ( click for details: us-nuclear-waste.pdf ) most of which is stored in water pools on-site of the power plants (see Yankee Rowe photo). Over 3,000 tons of waste is stored in New England Power Nuclear Power Plants (see photos).
Some point out the security issues of transporting the waste through highway, water, and railway to waste collection sites such as the proposed Yucca Mountain, Nevada. Studies have, also, shown and critics point out ways that nuclear plants are not secure form terrorist attacks.
For further explanation and more information on nuclear science click on MITcourse nuclear info.jpg
Many scientists studying energy supply and climate change remediation insist that nuclear power needs to be part of the solution.
Essential questions:
1) How many nuclear power plants would need to be built to meet increasing world energy demands and after the end of oil?
2. What is the risk analysis for nuclear fuel procurement and waste production management, transportation, as well as attacks on nuclear facilities? What are the realities and complexities of storing nuclear waste?
3. What is the economic structure and conditions for past, current, and future nuclear power plants?
4. What are the numbers for the world’s current nuclear fuel sources? What will they be in the future?
5. What impact does uranium mining and reprocessing have on the environment, workers, etc.?
6. What % of efficiency as a resource unto itself would be needed to replace the use of nuclear, how could this number be achieved?
WA Fossil Fuel Heating System
February 21, 2008
Up until the 1970’s WA heated its campus by burning coal in a 1940 model boiler (middle photo above) located underneath the Megaron. Water was boiled into steam and pumped through large pipes (top right) throughout all of campus. This centralized heating system lost vast amounts of heat energy during transfer through contact with the cold earth, and by burning coal, the dirtiest of the three major fossil fuels, emitted carbon dioxide, sulfur dioxide, carcinogenic hydrocarbons and particulate matter, mercury, and arsenic.
WA used the same boiler when it switched over to heating oil #6, a thick high sulfur content fuel.
At some point in the 1990’s WA began decentralizing its heating system, placing gas boilers (below middle) in each building. Cleaner less polluting natural gas is burned to heat up water which is then pumped (photo of motors, below right) in pipes throughout the building in the form of hot water rather than steam. In 2003, WA installed oil #2 (lower sulfur content) boilers (below left) to replace the old Megaron boiler, the only campus system burning oil.


















































