Geotechnical News • September 2016
21
WASTE GEOTECHNICS
need for capital investment to improve
the environmental performance of the
closed landfills, and increased operat-
ing budget to meet regulatory require-
ments for environmental monitoring,
maintenance and recovery.
Early in The City of Calgary’s pro-
gram, it was decided that common
assumptions made in past investiga-
tions and remedial activities should
be confirmed as part of this program.
Challenging those assumptions pro-
vided some of the more interesting
lessons learned.
Intrusive investigations begin in
the file room
Historically, investigations were
undertaken with a targeted scope of
work developed for a specific proj-
ect. The goals of this program were
broader than previous studies and
included a detailed historical review
and gap analysis undertaken prior to
scoping the intrusive investigation.
A municipal corporation such as The
City of Calgary is a complex organi-
zation. Development and delivery of
municipal services is a shared respon-
sibility across departments to balance
multiple municipal needs. In Calgary,
this balancing of municipal needs over
time has resulted in portions of landfill
lands sold, subdivided, converted to
roads and interchanges; leased and
developed to accommodate commu-
nication towers, commercial tenants
and public recreation; and, used to
accommodate buried and overhead
infrastructure. Significant time was
spent with other internal business
units looking for corporate records
that pertained to the landfills. Relevant
records, including geotechnical and
hydrogeological investigations, annual
reports, regulatory permits, access and
lease agreements, development plans,
waivers, block profiles, road construc-
tion and road closures, and historic
soil and water test results were found
across the corporation, including
Corporate Archives. Not surprisingly,
some pertinent documents were also
found in filing cabinets and storage
boxes that had not yet been classified
or added to the corporate record.
The historical review included a proj-
ect to digitize the physical documents
including site plans, reports, drawings
and correspondence. The electronic
documents are easily accessible and
searchable from an electronic file
system. After the documents were
digitized, the original records were
transferred to secure storage for reten-
tion, as required under the operating
approvals and in accordance to the
corporate records management policy.
It is anticipated that the electronic
catalogue will support improved
knowledge transfer to future projects.
A fence is just a fence
Home owners typically install a fence
along a property line to clearly sepa-
rate their land from their neighbors. A
fence is therefore commonly but erro-
neously interpreted as a property line.
When completing this program, it
was found that fences at the landfills
were typically not installed on the
legal property boundary. Security
fences were installed at East Cal-
gary, Shepard and Spyhill along the
perimeter of landfill operations and
around more sensitive infrastructure
such as landfill gas facilities. Fences
were used to define leased areas, to
demarcate parking areas, and to limit
illegal dumping and trespass. Fences
intended to be a physical barrier were
sometimes misinterpreted as prop-
erty lines, so that past investigations,
methane surveys and site inspections
sometimes stopped at those fence
lines instead of considering the entire
landfilled area.
Maps of the landfills have now been
produced that clearly show both the
property boundaries and the locations
of fences, reducing the ongoing risk
of a fence line being assumed to be a
property line.
A road is a road is a road
Three distinct types of roads were
identified during the program.
A few functional roads were found to
be outside of legal road plans. It was
only when looking for additional lines
of evidence, including road plans and
construction drawings, that it became
apparent that some of the roads was
not roads within a road plan.
Several road plans were identified
within landfills that were still open for
future public roads, including some
within the operating landfills. Such
future roads would be contrary to the
long term development plans for those
sites.
Lastly, several roads were identi-
fied that had been constructed after a
landfill was closed. New road plans
were filed and the landfill legal land
description was also changed.
Understanding the different types of
roads was important when considering
if any of the intrusive investigations
needed to include roads, and when
considering what authorization was
needed to investigate along roads. A
follow-up project was undertaken to
update legal plans as appropriate for
the individual landfills.
Stormwater ponds
Ongoing requirements related to land-
fill stormwater ponds varied depend-
ing on where and when the stormwater
ponds were constructed.
Stormwater ponds constructed on
the operating landfills were approved
under each individual provincial
approval to operate. Ponds included
both evaporation ponds within the
sites and ponds designed to hold water
for testing prior to release into the
watershed.
Stormwater ponds within Springbank
and Blackfoot were constructed after
both sites were closed. Although each
landfill operated and closed under a
Provincial Board of Health permit,
the ponds and final cover design were
approved under an amendment to
The City of Calgary’s approval for
municipal stormwater management.
Both ponds were designed to manage
on-site overland flows for release to a
