Sludge Watch ==> London Ont - what is this liquid sludge bit?

[Maureen Reilly]

Sludgewatch Admin:

London councilors should have a word with Hamilton.  London is deluded if 
they think that the same factors that limit Hamilton's sludge spreading 
(about an hour away from London) won't impact London sludge equally.

Here is why Hamilton's land application program isn't working (in their own 
words):

...............

The Problem
The practice of managing biosolids disposal through land application is 
increasing in both risk and complexity. The following is a list of emerging 
issues which limit the sustainability of a biosolids land application 
program:
• Recently implemented Provincial legislation (i.e. the Nutrient Management 
Act) have reduced and limited the future land bank available to the City for 
the spreading of biosolids onto approved agriculture lands.
• Increased regulated requirements for biosolids storage (i.e. 240 days) for 
off-season and inclement weather.
• Continuing concerns with certain biosolids constituents levels (i.e. 
metals, pharmaceutical residuals).
• Increased risk of utilizing the contingency disposal option of land 
filling. This is a result of off-season or times of inclement weather when 
land application is not feasible, or when biosolids storage is precluded.
• Competition for land from other municipalities.
• Securing agriculture lands from farmers and the reliability of retaining 
approved lands is difficult considering the land is obtained through a 
volunteer basis.
• Biosolids odours are generally problematic at the WWTP and the sites of 
application.
• Limited land application contractors to service the City.
• Increasing transportation distances to available lands.
• Historical stringent Certificate of Approval (C of A) requirements for 
land approvals.
• Increased concerns from the community of negative impacts land applying 
biosolids can pose to the environment.
• Increased expectation from the community as a result of improved 
technology, to treat biosolids to a higher standard.
As such, the overall sustainability of land applying municipal biosolids 
especially over the medium- to long-term is tentative and uncertain. As a 
result of this increased management risk and complexity a Biosolids Master 
Planning process was initiated.

(from Hamilton's Biosolids Master Plan)

......................................

City may try new sludge disposal method
Thu, August 9, 2007
The treatment would allow the human waste to be spread on farm fields.
By JONATHAN SHER, SUN MEDIA


London Coun. Cheryl Miller displayed her wit as a council committee 
recommended finding ways to dispose of what's delicately called "sludge 
cake."

Told of a plan to transform compressed human waste into fertilizer for 
farms, Miller said, "So, you'll be able to have your cake and eat it too."

The city normally burns the waste, but its incinerator will close for seven 
months beginning in February or March for an overhaul.

Sending it to the landfill is a costly and smelly option that staff would 
rather avoid -- their opinion seconded by council's environment and 
transportation committee.

This week, the committee recommended staff try another option that would 
make the treated waste useable for farms but using a new method that's far 
less costly than what has been available.

The new process, developed by universities in Waterloo and Guelph, turns 
sludge into a liquid in a way that destroys pathogens, John Fitzgerald, the 
city's manager of sewer operations, told the environment and transportation 
committee on Monday.

The liquid can be applied to farmland, he said.

Unlike older technologies, the new process doesn't require the purchase of 
costly equipment that digests the sludge to kill pathogens.

"The capital cost of digesters is so expensive . . . tens of millions of 
dollars," said Ron Standish, the city's director of waste water and 
treatment.

If the new method proves successful, London could use it regularly since its 
incinerator at the Greenway pollution plant must be shut down one month a 
year for maintenance, Standish said.

Incineration is the cheapest way to dispose of sludge, costing London $1.35 
million a year. Sending it to the landfill would cost $4.9 million.

But the city should consider the environment, too, Controller Bud Polhill 
said.

"Sometimes cost-effectiveness isn't the issue. In this day and age, people 
ask, 'What about the environment?' " Polhill said.

....................................

(Admin:  liquid sludge..like liquid manure...poses extra problems of runoff 
into surface water..often facilitated by tile drains.  Most of Ontario 
farmlands are tile drained, so liquid sinking into the soil is drawn off and 
directed to the nearest creek or river.  Also much of this part of Ontario 
soil is fractured limestone, allowing rapid penetration of sludge into the 
groundwater that is the drinking water source for rural residents.   
Remember Walkerton..  Current thermal technologies have an air emissions 
footprint that is a 99% reduction of air emissions compared to the earlier 
generation of incinerators, AND they stop the emissions of pollutants from 
the ancient coal fired plants by substituting renewable energy sources)