Royal Rouge Trail Erosion Control Project - Toronto and Region ...

neighboring Gyimah Sparks site (AkGs-044) (TRCA 2010b) and Jhuman site (AkGs-045)
(TRCA 2010c) were dated predominantly to the Middle and Late Archaic, it was anticipated
that this site would also prove to date to the Archaic as well. The third and final objective of
the Stage 3 investigation was to determine the soil profile and the degree of disturbance at
the site, particularly because the cluster identified during the Stage 2 assessment was
located within three meters of an in-ground swimming pool. Additionally, Stage 2 testing
across the entire project area indicated that soil depths varied and that there were pockets of
disturbance with intermixture of 19 th and 20 th century materials. Stage 3 investigative units
were hand excavated in 1m² units according to current technical standards on a five metre
grid until units contained no artifacts, until areas of severe disturbance or obstacles were
reached, or until a property with a registered site was reached that was to be assessed
independently. Occasionally units were slightly relocated if stumps, rock gardens or other
immovable objects were in the way. The TRCA restoration/erosion control staff responsible
for the slope remediation advised that excavations within the drip line of trees on the
properties be avoided and that any plantings that contribute to the stability of the adjacent
slope be avoided. However, no large trees were encountered within the area excavated for
this site. Units were excavated in stratigraphic layers to five centimeters below subsoil. Once
the limits of the site were identified, additional units comprising at least 20% of the grid unit
total were excavated in areas of dense artifact concentrations or where positive test pits were
encountered during the Stage 2 assessment. Soil was screened through 6mm mesh to
facilitate artifact recovery and all artifacts were collected and retained.
Fourteen 1m² units were excavated during the Stage 3 investigation. Ten units were
excavated on a five meter grid with an additional unit attempted but the area was thoroughly
disturbed from pool and patio construction. An additional four units were excavated in areas
of dense artifact concentration or in selected locations where positive Stage 2 test pits were
encountered. No diagnostic Woodland artifacts, such as body sherds, were encountered;
instead all artifacts found were lithics. A total of 118 artifacts were collected from the 14 1m 2
units. This included 117 flakes, and 1 projectile point fragment. The Stage 3 investigation
suggested that the Corvese site is a Late Archaic campsite. Due to the threat of erosion and
the proposed erosion control measures to be implemented, it was determined that avoidance
and protection was not a viable option for this sensitive resource and that Stage 4 excavation
was required.
The purpose of the Stage 4 excavation of the Corvese site was to document and remove the
site data as completely as possible given the constraints of working in a subdivision with
fences, decks, swimming pools, gardens and disturbed soils and also with the inherent risks
of moving large quantities of soil in an area at risk of severe erosion. In accordance with
Ministry technical standards, Stage 4 1m² units were excavated surrounding any Stage 3
units that contained lithic artifacts numbering ten or more, or with diagnostic lithic artifacts. A
total of 37 1m 2 units were excavated during the block excavation. The Stage 4 units were
excavated in stratigraphic layers to five centimeters below subsoil. Wherever possible the
excavation of 1m² units continued until there were yields or fewer than ten artifacts at the
edge of the block excavation. Exceptions were limited to areas of disturbance alongside the
swimming pool. Ordinarily test units would be excavated up to 10 metres beyond the block
excavation, however in this instance the limits were constrained by a steep slope to the north,
and a swimming pool and deck to the south. To the west, the Jhuman site (AkGs-045) was
fully excavated under PIF P338-010-2010 (TRCA 2010b). In total, 602 artifacts were collected
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Project Plan
Toronto and Region Conservation Authority
Royal Rouge Trail Erosion Control Project January 2010