December 12‚ 2011
MassDEP’s Proposed Approach to
Anaerobic Digestion: Solution or Stomachache?
MassDEP has proposed amendments to
the Commonwealth’s solid waste regulations to facilitate the recycling of
food waste and other materials with high organic content that can be
converted to energy. Under the new approach, eligible facilities would no
longer be classified as solid waste management facilities requiring site
assignment from the host municipality’s local board of health. Instead they
would need authorization from MassDEP under a
permitting system MassDEP has also proposed. The
hope is that siting such facilities will now be
(from MassDEP’s Draft 2010-2020 Massachusetts
Solid Waste Master Plan)
To recycle an additional 350,000 tons of organic material by 2020
(Massachusetts currently recycles about 100,000 tons of organic material),
To help reduce overall waste generation 30 percent by 2020 and
80 percent by 2050.
MassDEP’s current rules exempt
small organic material recycling and composting facilities from site
assignment requirements. Anaerobic digesters, which convert organic
material to energy, have still needed either a local site assignment or a
project-specific Determination of Need from MassDEP.
This makes it more difficult to site these facilities.
MassDEP and industry agreed that
the Commonwealth’s solid waste regulations should specifically address
anaerobic digestion in a way that is consistent with the Commonwealth’s
recycling objectives. MassDEP launched a Task
Force on Building Organics Capacity to recommend ways to promote the siting and development of additional anaerobic
digestion, composting, and recycling capacity in Massachusetts. The
proposed amendments were based in part on the Task Force’s findings.
The amendments would modify the definition of solid waste so
that facilities handling organics materials would not require site
assignment as a “solid waste” facility. Instead, such facilities would have
to fit within one of several categories and sub-categories:
small storage and processing facilities that handle certain organic
or recyclable materials;
larger recycling, composting, and conversion operations that qualify
for one of several new “Permit by Rule” sub-categories; and
operations that must obtain
facility-specific recycling permits because they exceed the limits on the
size to qualify for a Permit by Rule.
To stay within the Permit by Rule limits, composting
facilities could accept up to 30 tons per day (TPD) and aerobic or
anaerobic digesters could accept up to 60 TPD. Also, Permit by Rule
facilities would have to meet tough standards on the percentage of input
that becomes residuals – the waste remaining after treatment or processing.
The proposed regulations would limit residuals to 5% of the weight of the
materials processed on a quarterly basis.
The proposed amendments also would authorize the use of source-separated
vegetative and food materials in anaerobic digesters at Publicly Owned
Treatment Works (POTWs), with MassDEP approval.
While the existing rules do not prohibit anaerobic digesters, MassDEP hopes to encourage more installations by
explicitly allowing their use.
MassDEP will conduct public
hearings on its amendments in December 2011 and January 2012; written
comments are due January 23, 2012.
Will it work?
Facilities large enough to be economically feasible, and to
make a major contribution to MassDEP’s
objectives, are likely to exceed the Permit by Rule tonnage limits and find
it difficult to meet the residual limits. These larger facilities will need
to obtain facility-specific recycling permits involving public notice,
comment periods, and opportunities for adjudicatory appeals.
As a result, the industry may continue to find it difficult
to develop additional anaerobic digestion facilities. In order to meet its
objectives, MassDEP may need to expand the
allowed tonnages and relax the residuals standard.
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