brownfields to greenfields 1135 a field guide … is the use of plants to remove contaminants ......
TRANSCRIPT
1135
Most urbanized areas contain limited amounts of suburban lawn, yet a large population that needs to be fed. Instead, we find a growing number of vacant lots in Ameri-can cities, many of which are contaminated by their industrial past. Remediation of toxic soil, contaminated with heavy metals, hydrocarbons or PCB, is costly. Especially owners of small properties shy away from these costs and leave their sites vacant, underutilized and undervalued for years.This brochure is designed for all these individual property owners and gives hands on instructions how to utilize nature in their favor and convert this enormous land potential into a productive landscape in American cities.
BROWNFIELDS TO GREENFIELDS A field guide to phytoremediation
32
1135
EXCAVATION AND FILL
$50,000 -100,000 $5,000 - 8,000
PHYTOEXTRACTION
Half of all vacant lots in New York are smaller than 2,500 sf and owned by individuals. Costs associated with reme-diating lead contamination on such a lot:
In New York City, the most populous of American cities, 7.1% of its land is currently vacant. This equals 11,000 acres of underutilized land, roughly the size of Manhattan.
Enough land to grow vegetables and fruits for all of New York City‘s Public School children annually. The national avarge of vacant land in cities is 15%, in some cities up to 45% of land is va-cant. Much of it is possibly contaminated by previous industrial uses on the site or leftover building materials, especially lead-based paint. Utilizing this land for food production, recrea-tion or housing is not safe unless, the soil and groundwater are free of toxins.Remediation - typically in the form of exacavation of contaminated soil is costly. Instead, the-se properties lie vacant for years...underutilized and toxic, their value dampened by sights of abandonement and potential contamination.The following pages illustrate, how property owners can use these years to their advantage and initiate a slow, but cost-effective clean-up process using nature as their ally and collectiv-ly add 11,000 acres of productive landscape to the city‘s healthy environment.
VACANTLAND Growing a productive urban landscape on vacant land
54
AsAs
E
E
E
E
AsE
AsE
Pb
Pb
Contaminant taken up into plant tissue
PCB
PCB
Enzymes fragments contaminant and produces new plant fiber
Enzymes in the the roots immobilize contaminants
E
TCE
ETC
Contaminant are modified along the way and evaporate
AsAs
E
E
E
E
AsE
AsE
Pb
Pb
Contaminant taken up into plant tissue
PCB
PCB
Enzymes fragments contaminant and produces new plant fiber
Enzymes in the the roots immobilize contaminants
E
TCE
ETC
Contaminant are modified along the way and evaporate
AsAs
E
E
E
E
AsE
AsE
Pb
Pb
Contaminant taken up into plant tissue
PCB
PCB
Enzymes fragments contaminant and produces new plant fiber
Enzymes in the the roots immobilize contaminants
E
TCE
ETC
Contaminant are modified along the way and evaporate
AsAs
E
E
E
E
AsE
AsE
Pb
Pb
Contaminant taken up into plant tissue
PCB
PCB
Enzymes fragments contaminant and produces new plant fiber
Enzymes in the the roots immobilize contaminants
E
TCE
ETC
Contaminant are modified along the way and evaporate
1135
PHYTOEXTRACTION: Plants take up contaminants - mostly metals, metaloids and radionucleids- with their roots and accumulate them in large quantities within their stems and leaves. These plants have to be harvested and disposed as special waste.
PHYTOSTABILIZATION: Some plants can sequester or im-mobilize contaminants by absorbing them into their roots and releasing a chemical that converts the contaminant to a less to-xic state. This mechanism limits the migration of contaminants through water erosion, leaching, wind, and soil dispersion.
PHYTOhwwDEGRADATION: Plants take up and break down contaminants through the release of enzymes and me-tabolic processes such as photosynthetic oxidation/reduction. In this process organic pollutants are degraded and incorpo-rated into the plant or broken down in the soil.
PHYTOVOLATILIZATION: Some plants take up volatile contami-nants and release them into the atmosphere through transpiration. The contaminant is transformed or degraded within the plant to create a less toxic substance before and then released into the air.
PHYTOREMEDIATION is the use of plants to remove contaminants from the environment. By harnessing the natural capabilities of plants you can remediate toxic soils, groundwater, surface water, and sediments. Phytoremediation is a low-cost alternative to traditional brownfield reme-diation. Instead of removing tons of toxic soil and filling the site with new clean soil, plants remove contaminants from the soil and store it within thier plant tissue. Contaminants succesfully removed in field studies have include heavy metals, radionuclides, chlorinated solvents, petroleum hyd-rocarbons, polychlorinated biphenyls (PCBs), pesticides and explosives.Different plants have different remediative qualities. In order to successfully remediate toxins in soil or water, the appropriate plant groups have to be planted and monitored. Plants offer an aesthetic as well as an environmental value to the city beyond the phytorem-diation process.
IMPROVED AIR QUALITY and REDUCTION OF STORMWATER RUN-OFF are among the additional benefits of planting on sites that would otherwise be underuti-lized until funding for soil removal becomes available.
PHYTOREMEDIATION Using the power of nature to clean your soil
76
1135
1. FEBRUARY 2. FEBRUARY 3. MARCH 4. APRIL 5. MAY - NOVEMBER 6. NOVEMBER 7. DECEMBER 8. JANUARY
1. COLLECT A SOIL SAMPLEGather soil samples by taking them from at least 4 different areas per every 400 sq ft of space. Samples should come from approx. 6 inches below the surface and should not contain any gravel, grass, trash...etc. You can mix the samples to form a composite sample of your entire lot.
2. SEND IT TO A LABBrooklyn College and Cornell University provide inexpensive soil testing services (approx. $30 for heavy metal tests -see re-sources on page 8/9). Fill a ziplock bag with your soil and send it to their lab together with information about your site. You will get a report in about 2 weeks.
3. CREATE A REMEDIATION STRATEGYFrom the test results, determine, if and how to remediate con-taminants. Utilize the table on page 8/9 to decide on the plants that would best help you to clean up your lot nad make a plan how many you need.
4. START PLANTINGMost of the seeds you will need, are sold online. Sow and germinate them in a small container and water them regularly. Transplant them to your site, when they are about 3“ high and after the last spring frost. Manage them as garden plants and watch them grow.
5. HARVEST AND RE-PLANTAfter about 14 weeks, your plants are saturated with heavy metals, PCB or other toxins. You can harvest the entire plants including the roots, stems and leaves and repeat this growing cycle as often as climate permits.
6. DISPOSE AS HAZARDOUS WASTESome of the plants, are hyperaccumulators. They store the toxins within their plant tissue and are now toxic themselves. Check for the location of the Special Waste Drop-Off site in your borough and dispose them as hazardous waste. Keep them away from children and animals.
7. RE-TEST YOUR SOILAt the end of the growing season, re-test the soil to under-stand the improvements. You can also test the plant material, if you are curious about the change. Depending on the level of contamination, you may have to repeat this planting process over 2-3 years.
8. GET A GREEN PROPERTY CERTIFICATIONNow, that doesn‘t really exist yet, but the New York City De-partment of Environmental Remediation is currently develo-ping the New York City Green Property Certification Program, which will signify that a property was investigated, cleaned up and is protective of both public health and the environment.
REPEAT THIS CYCLE NEXT YEAR, IF NECESSARY
DOITYOURSELF Eight simple steps to clean up your vacant lot
PbCr
Hg
MTBE
DDTPCP
PCBTCE
Highland Bent Grass Agrostis castellana
Chinese Brake FernPteris vittata L.
Common Bent GrassAgrostis capillaris L.
Arsenic 16ppm 16ppm 13ppm
Mercury 0.81ppm 0.81ppm 0.18ppm
Chromium 180ppm 36ppm 30ppm
Lead 400ppm 400ppm 63ppm
1ppm 1ppm 0.1ppm
21ppm 10ppm 0.47ppm
100ppm 62ppm 0.93ppm
6.7ppm 2.4ppm 0.8ppm
7.9ppm 1.7ppm 0.0033ppm
PHYTOSTABILIZATION
PHYTOSTABILIZATION
PHYTODEGRADATION
PHYTODEGRADATION
PHYTOEXTRACTION
MAXIMUM LEVELS OF CONTAMINANT FOR:
Indian mustardBrassica juncea L.
Rapeseed PlantBrassica napus
WillowSalix
ZuchiniCurcurbita pepo
Paul’s Scarlet RoseRosa
Crested WheatgrassAgropyron cristatum
PumpkinCurcurbita
Alpine PennycressThlaspi caerulescens
Common RagweedBrassica olercea
Giant DuckweedSpirdela polyrhiza
SunflowerHelianthus annuus
Blue Sheep FescueFestuca ovina
Seapink ThriftArmeria maritima
PinePinus
White rot fungusPhanerochaete chrysosporium
Common WheatTriticum estivum
CONTAMINANT TYPICAL PLANTS
As
Polychlo-rinated biphenyls
Trichloro-ethlene
Methyl tertiary butyl ether
Pentachloro-pheno
Dichloro-phenyltri-chloroethane
Farming Animals.. ..Growing Food
Single Family Houses.. Gardening..Playground
Multi Family Housing.. ..Recreation..Park
Eastern cottonwoods Populus deltoides
Often found in lead-acid batteries, light-emitting diodes, paints, dyes, metals, pharmaceuticals, pesticides, herbicides, soaps, and semiconductors.
Typically used as a fuel additive in gasoline. Common in areas that were exposed to leakage from the gasoline storage and distribution systems.
PCBs appear as colorless to light yellow oily liquids or waxy solids. They accumulate in fish and marine mammals at much higher levels than in sediments and water.
98
1135
1. US Environmental Protection Agency. „Re: Contaminant Focus.“ Contaminated Site: Clean-Up Information. US EPA Office of Superfund Remediation and Technology Innovation, Washington, DC, 7 Jan. 2010. Web. 22 Apr. 2010. 2. New York State Department of Environmental Conservation. „Re: 375-6-8 Soil Cleanup Objective Tables.“ Subpart 375-6: Remedial Program Soil Cleanup Objectives. NYS DEC, Albany, NY, 14 Dec. 2006. Web. 22 Apr. 2010. 3. Wikipedia, The Free Encyclopedia. „Re: Hyperaccumulators Table - 1 and 3.“ Redirected from, Phytoremediation, Hyperaccumulators. Wikimedia Foundation, Inc. San Francisco, CA, 14 Apr. 2010. Web 22 Apr. 2010. 4. U.S. EPA. 1996. Soil Screening Guidance: User‘s Guide. Office of Emergency and Remedial Response, Washington, DC. EPA/540/R95/128. 5. Schippers, R.R. & Mnzava, N.A. Brassica juncea (L.) Czern. [Internet] Record from Protabase. van der Vossen, H.A.M. & Mkamilo, G.S. (Editors). PROTA (Plant Resources of Tropical Africa / Ressources végétales de l’Afrique tropicale), Wageningen, Netherlands. 2007. Web. 22 Apr. 2010. 6. Duke, James A. Brassica juncea (L.) Czern. Handbook of Energy Crops. unpublished. Center for New Crops & Plant Products, Purdue University, 1983. Web. 22 Apr. 2010. 7. Shayler, Hannah, Murray McBride and Ellen Harrison. „Re: Guide to Soil Testing and Interpreting Results.“ Cornell Waste Management Institute. Department of Crop & Soil Sciences, Ithaca, NY, 15 Apr. 2009. Web. 22 Apr. 2010. 8. Environmental Science Analytical Center. Soil Testing Brochure. Department of Geology, Brooklyn College, Web. 22 Apr. 2010. 9. Washington State Department of Ecology. Dirt Alert - Soil Sampling Guidance for Owners, Operators and Employees of Small Properties Where Children Play. Publication #06-09-099. Olympia, WA, Sep. 1999. Web. 22 Apr. 2010. 10. New York City Department of City Planning (Land use sumary, 2007) 11. Michael A. Pagano and Ann O’M. Bowman: Vacant Land in Cities, Brookings Institute Report, 2001
PERIODICTABLE Common contaminants in urban soil and their natural enemies