Solid Wastes Monitoring

Mills produce mainly two kinds of solid waste: sludge from the secondary treatment plant and ash from the power boilers. However, in most mills, sludge is now de-watered using large presses and then burnt in the power boilers. Interior mills do not have as much problem with sludge, because they use large lagoons for treatment. Coastal mills which installed UNOX systems expected to burn the sludge, but this material is difficult to handle, hard to dry, causes increases in sulphur dioxide emissions, and gasses off toxic hydrogen sulphide compounds.

Many mills in B.C. have recently applied to the BC Ministry of Environment to disperse sludge from the secondary treatment facilities to forests and even agricultural lands. Analysis of the sludge provided by the mills has until now always been incomplete. Most noticeably, there is inadequate information about the non-dioxin toxic content of the sludge, such as phenolics and pthalates. Recently a multi stakeholder committee is looking at establishing criteria for sludge as a soil amendement.

Others wastes that are landfilled include dregs, grits, quicklime, fibre, hog fuel, lime mud, sawmill waste, asbestos, waste materials containing asbestos and miscellaneous waste.

Most old land fills do not have plastic liners and sometimes even lack leachate collection systems. Once they are full, they are "capped" with an impermeable material such as asphalt and earth is spread over the top to cover the "mess". All recently built land fills have plastic liners and leachate collection systems which are directed to the secondary treatment systems.

Mills have to follow the Landfill Criteria for Municipal Solid Waste. However, under the Waste Management Act, the Special Waste Regulation includes siting and operational requirements for mill landfills. Surprisingly, the definition of special waste does not apply to mill wastes! This is peculiar as these wastes may contain dioxins and other toxic materials. According to this regulation, mills must carry out an approved monitoring program by establishing a groundwater monitoring system, sampling groundwater sufficiently often to provide data that is representative of varying groundwater flow conditions. BC Ministry of Environment staff look only at trends in the different parameters and constituents of groundwater (specified in What's Monitored?) in the reports submitted by the mills. A landfill is in a non-compliance situation, with regard to groundwater quality, when analytical data from upgradient and downgradient groundwater monitoring wells for any parameters or chemical constituents are significantly different using approved statistical methods.

All mills have refuse permits for their landfills administered by the BC Ministry of Environment regional office. Mills pay $0.50 per tonne of refuse that is land filled. In the permits, usually the following is specified: the maximum rate of discharge (in m³/day), the nature of the waste and monitoring and reporting requirements.

What gets monitored?

Some mills have to monitor both the leachate and groundwater (for example Western Pulp in Woodfibre). Some only the groundwater. Some mills do not have any monitoring requirements for leachate or groundwater specified in their refuse permits, most noticeably most mills in B.C.'s interior.

Monitoring requirements specified in permits may include sampling, usually twice a year (preferably in May and October), of the following parameters and constituents:

• grab sample of leachate: pH, conductivity, BOD and Rainbow trout toxicity.

• groundwater wells: pH, temperature, conductivity, BOD, Chemical Oxygen Demand (COD), toxicity, total dissolved solids, total organic carbon, sodium, calcium, magnesium, manganese, iron, AOX, chlorinated phenolics, PAHs, tannin/lignin, dioxins, furans and heavy metals

Monitoring requirements vary enormously from one landfill to another. It is not always clear why some parameters and constituents are monitored in some land fills and not in others. Factors such as soil composition and average annual rainfall are considered by the Regional BC Ministry of Environment Industrial Section Head when determining the monitoring requirements.

Monitoring reports are usually submitted by the mills once a year to the BC Ministry of Environment regional office.

* Excerpted from Monitoring Pulp and Paper Mills in British Columbia - A Citizens' Handbook, by Stefan Ochman, 1997 ISBN 0-9680431-1-9 , 118 pgs. Out of print