Tuesday, March 13, 2012

Soil Rehabilitation Not Capping

Soil Safety protocol and licensing procedures should emphasize rehabilitation rather than capping. Thus, require all soils to be tested rather than allow barrier and soil replacement on untested sites. Soils with low or medium levels of lead and other contaminants should be remediated by phytoremediation or soil replacement without a barrier. Only very toxic sites should be required to use the geotextile and new soil remediation procedure.

The preliminary “Soil Safety” recommendation for Boston provides two options for urban agriculture on sites over 5000 square feet: 1) barrier and new soil (presented first, and in some detail) or 2) “provid[ing] results of testing by a Licensed Site Professional (LSP) demonstrating that the existing soil is safe for growing. The specific protocols and licensing procedures for such testing will be developed concurrently with the draft Urban Agriculture rezoning recommendations.” It seems misguided to emphasize capping with geotextiles and new soil. This system just defers resolution of the toxic problem on our grandchildren or great-grandchildren. Although I could not quickly find life expectancies for the recommended geotextiles (I have an email enquiry pending to a manufacturer), it is clear that they will not last more than a generation or two. Unfortunately, the U.S. continually approves technologies and kicks the can down the road as far as longevity and remediation. Just think of all the leaking buried oil tanks being removed from homes (often with strict liability for current owners) and of the remediation of buried gas and diesel tanks at former gas stations. These were installed with the same mentality that the geotextile solution is being touted – “the present” is what matters and the future can take care of the problems we create by developing new technologies. Unfortunately, the current global warming crisis is demonstrating that the synergies between all these deferred solutions and ignored externalities have damaged the environment and ultimately ourselves. Sustainable thinking requires that we think in the long term, for “seven generations,” and solve problems now when possible.

In the instance of remediating contaminated urban soils for agriculture, this means that phytoremediation and other solutions that actually clean up the site for the long term should be emphasized, rather than short-term solutions. This is especially true for the soils with low and medium levels of lead. For example, the UMass Extension Center for Agriculture flyer, issued by the Soil and Plant Tissue Testing Laboratory, entitled “Soil Lead: Testing, Interpretation and Recommendations” recommends that farmers growing in soil with “Low” levels of lead contamination (less than 22 mg/kg extracted lead/less than 299 mg/kg estimated total load) should follow “good gardening practices” to reduce lead exposure. At this minimum level of contamination, the danger is more to the gardener/farmer than to the consumers of the crop. Consequently, a “low” level of lead in soil is particularly suited to phytoremediation rather than capping and new soil. Moreover, lead contamination is typically present only in the top few layers of soil. As a result, the preliminary “Soil Safety” recommendation for Boston should be amended to separate out soil tested at low levels of lead from the requirement for geotextile barrier and new soil and instead require phytoremediation and/or new soil without a barrier. This process can still be overseen by a Licensed Site Professional to ensure that the produce is safe for consumption, but this emphasis gives the signal that remediation is the preferred option, where possible. As the proposed ordinance now reads, it emphasizes barrier and soil as the preferred options for all soil types and will result in the capping of soils that could easily be rehabilitated.

Phytoremediation should be emphasized over soil replacement, where possible. Phytoremediation is a proven technology that produces less volume of contaminated materials (plant residue) that can be buried rather than soil replacement at much more volume of landfill. In addition, soil replacement merely shuffles the lack of good soil around, taking soil from one place and moving it to another rather than rehabilitating existing soil. It is my understanding that the contaminated plant materials can also be incinerated under special conditions, and the toxic metals recovered in a pure state, so that there is very little volume of toxic residue to be disposed of or reused in manufacturing processes. It seems that city, state and federal money would be better spent creating these types of incinerators, or discovering other solutions to disposal of small amounts of toxic materials, rather than emphasizing capping and new soil as the favored solution in all instances.

By Right Small animal husbandry Not conditional use

I am very excited that the Mayor and the BRA are considering ways to rezone to assist agriculture in the city. However, I am concerned that the fears of a few vocal citizens are being allowed to drown out the groundswell of support for these initiatives. Particularly, I have been following the course of the Legalize Chickens in Boston folks and am dismayed to see on your website that the question of small animals was tabled last year. I am glad that this proposal is on the table for discussion this year. Again, it comes down to whether or not the City wants to promote agriculture or merely permit a few isolated show-pieces.

Thus, small animal husbandry should be allowed by right rather than as a conditional use. The Board of Health and other city and state agencies can create reasonable standards for the welfare of the animals and the public health and safety that can be incorporated into the zoning code to allow reasonable by right small animal husbandry. These zoning standards, along with the laws already in place regarding nuisance are certainly sufficient to remedy the few instances in which an urban farmer, gardener or householder violates animal welfare or health and safety standards.

In my experience, if you make the use conditional, a few zealous but misinformed individuals will have disproportionate power to stop or delay reasonable uses. Take the recent example of a household with a few ducks and chickens in Cambridge that was the subject of a recent Northeast Organic Farming Association Workshop on Backyard Poultry that I attended. According to Allison Fastman, one of the affected householders, despite the fact that the household gathered 90 signatures from neighbors supporting the use of a small backyard duck and chicken flock for fresh eggs, one adjacent neighbor with lot of unfounded fears about animals was able to convince the zoning board to force the household to remove the animals with just a few signatures. Assuming “a few” means less than 10, that means that 90 people were for the change and 10 people against. Why did the 10 prevail? – that is not democracy in action. Even if the adjacent landowner’s opinion was given some extra weight because of her proximity, it still seems that the right result was not reached. Rather than chickening out when a few vocal citizens make a noise (couldn’t resist the pun ) the city should take a principled stand and lead the people into a sustainable future. It may be that a public education campaign is needed. But it may also be that a few people will never agree with urban agriculture. Why should they win in the political process? They are far fewer in number and a sustainable future is what is needed. I have a few neighbors who still disagree with busing!

An example: Arlington recently approved a change in the zoning bylaw to allow residents to keep up to six hens. Arlington’s Board of Health oversees the permitting process and requires hen owners to secure their pens from predators and clean them at least once a week.

Composting in Boston should include access to off-site materials

The other big problem so far at these hearings on urban agriculture zoning is the city's current stance on composting. Apparently in response to some public outcry last year during the initial planning phase, the BRA's proposed zoning amendment for the Pilot lots and the Preliminary Recommendations for Boston restrict composting inputs to “using only organic matter generated on-site.” As the Keynote presentation from Will Allen (Growing Power http://www.growingpower.org/) so eloquently demonstrated, to have adequate amounts of compost and soil in urban areas available for farming, it is necessary to allow urban farmers access to off-site waste materials from coffee shops, arborists, grocery stores, restaurants, leaf pick-up, etc. Thus, the on-site restriction is misguided and will ultimately severely restrict the ability of urban farming to flourish. The diversion of materials from landfill is an added benefit.

It comes down to this: does the City want to promote urban agriculture or merely permit a few isolated instances as show-pieces? If the former, then composting inputs necessarily include access to off-site materials from city businesses. For similar reasons, as demonstrated by the Growing Power example, Businesses or non-profits creating compost from city business’ waste materials should be allowed and encouraged within the city and its environs.

At the March meeting, more information came out about this: the BRA officials are concerned about the scale of the composting operations - they don't want a lot of activity from trucks and other large machinery in residential areas. Rather, they argue, commercial districts could hold the composting businesses [and presumably sell compost to urban farmers in residential areas]. Fair enough. Yet, I don't think that these planners understand how much compost is needed on depleted soils, or if the system of agriculture is biointensive - getting a large yield out of a small area through intensive composting. By making these small farmers purchase compost, they are driving up the operating costs. Presumably, a truck would come periodically and drop off the compost - so they must be contemplating some truck activity. To keep costs down, and to honor the worry about scale of composting onsite, the better method would be to remove the restriction on on-site inputs and rather limit composting to a portion of the area of the site -- say 1/4. I would need to do some calculations here to come up with a realistic number for each of the types of farming. Small Plot Intensive farming is being used more and more in small city plots -- it creates 3-4 consecutive harvests of high-value crops from the same rows in one season. Each time a new crop is planted, at least 2 inches of compost is reapplied.

Contamination of urban soils

This problem of contamination of urban soils is a difficult problem -- and people can get downright stubborn about it. I attended the second public meeting of the Mayor's Working Group on Urban Agriculture in March, facilitated by planner John "Tad" Read from the Boston Redevelopment Authority. He had brought someone to speak from the Public Health Commission, Robert Plant, I believe, who is advocating geotextile soil barriers and testing of all produce before sale. In talking over with him the logistics of the geotextile barriers after the meeting, he is envisioning that the barriers will need to be inspected every year -- he sees this as a "natural" part of the process, since soil is turned over every year.

In my view, this is completely unworkable as a procedure. First, not all systems of agriculture turn over the soil, for example, no-till and permaculture systems. Second, if you plant perennial crops, such as asparagus or fruit bushes, you cannot disturb the roots or you will lose the plants. Robert sees no problem with this -- he'll just restrict the plants that can be used. This will impact not just perennials, but those annual crops whose roots grow too deep and would attempt to penetrate the geotextile barrier into the untreated soil. This raises the third objection: under this scheme, the public health commission will dictate the kinds of plants that can be grown, whether or not these are commercially feasible. Fourth, the process of digging up the soil without damaging the barrier, removing the soil and storing it, inspecting the barrier, and then returning the soil is prohibitively difficult. Where would you store the soil? A great deal of the site area would need to be dedicated as open space for this purpose with no other productive use. Most of the small farmers are going to use hand-tools -- thus it is a LOT of extra work at the beginning or end of the season to dig up all the soil, move it, and then put it back --plus it seems that the BRA staff is particularly squeamish about the use of power tools, trucks and other machinery anyway due to perceived public outcry in residential neighborhoods so limited types of tools could be used.

Tuesday, February 21, 2012

Fruits don't uptake heavy metals

I've just returned from my second workshop in the Permaculture Design Certificate program and have learned that fruits do not generally uptake heavy metals, including lead. This means that I can leave the two trees that survived in the front yard where they spent their first year. I will need to send a sample of the fruit (when these are produced after years 2-3) to a soil lab, such as UMASS-Amherst to be tested, but this is exciting news for urban dwellers!

Tuesday, January 17, 2012

Hello stranger

Well, after a long, productive break, I'm ready to share with all of you again. The apple trees have continue to grow over their fallow year and I've learned a lot -- so much that I've decided to move the "front tree" yards to the side yard to protect from potential lead contamination, and to grow the trees in a taller format, rather than chain link height, even tho' I still believe it's a great idea for urban agriculture. I've expanded my purview to include all of urban agiculture. Thus, this blog is contained within a google site on urban agriculture. I'll be attending a 4 weekend certfification workshop on permaculture beginning this weekend, and will keep you posted on my journey to become an urban market gardener.