State wants more details from OMYA's plan for Danby quarry
November 23, 2001
by Anita Pomerance
DANBY OMYA recently sent the Vermont Department of Environmental
Conservation its hydrogeologic study plan for the proposed Jobe Phillips
quarry in Danby a plan Hydrogeologist Michael Smith said was on the right
track, but lacking in detail.
Eric Sorenson, ecologist with Vermont's Nongame and Natural Heritage
Program, informed OMYA that "additional detail and work is necessary above
what is proposed in the study plan in order to adequately evaluate the
potential effects of the project."
In question is OMYA's proposed marble ore quarry on the east slope of Dutch
Hill, in the Danby Four Corners area.
The study plan was submitted by Eric Hanson, hydrogeologist with Pioneer
Environmental Associates, retained by OMYA.
Current plans are for the ore to be conveyed to the OMYA plant in Florence,
to be ground into calcium carbonate, which is used for a multitude of
products, including paper and plastic.
Residents in nearby towns have opposed the proposal because of the possible
impact on quality of life and the environment, including noise from
machinery and explosions, dust, truck traffic, and negative effects on the
landscape. Others see the proposed quarry as a possible source of jobs.
The Vermont Agency of Natural Resources has expressed concern about the
effect of water removal on nearby wetlands, including swampy "fens" that
shelter rare species of plants and animals. Sorenson asked OMYA for the
study in September 2000.
Smith noted that the study did not give an assessment of how much water
would be pumped from the quarry information essential for developing a
model to predict the effect of the quarry on the fens.
The OMYA study plan describes six tasks to be performed over approximately
one year. Sorenson had a few concerns, and Smith had questions about most of
OMYA proposed to review existing information from ANR, U.S. Geological
survey maps, and Natural Resources Conservation Service. The study would
describe "the hydrogeologic setting and character of the site" and watershed
boundaries, using maps and well logs.
Sorensen noted that the ANR needed to know the groundwater recharge areas of
the fens, not just watershed boundaries. He also recommended adding
dissolved calcium to the list of water quality features, as it was a
"primary concern" for fens.
Smith specified that movement of groundwater between the quarry site to the
wetlands needed to be studied in detail.
Second, OMYA proposed using aerial photos of the landscape to find traces
that might reveal vertical fissures in the bedrock where groundwater was
likely to flow.
Smith commented that the proposal to use aerial photos did not include
verification and observation in the field, which he considered "essential."
OMYA's third task was to install groundwater monitoring wells and
piezometers to measure water levels. The plan noted that the study would be
confined to OMYA property because six adjoining property owners had denied
access to their land for study.
In his memorandum, Smith noted that the study did not propose using the
trace analysis of rock fissures to help decide where to put the wells.
He questioned OMYA's proposal to use existing core holes for wells, as their
depth is unknown, and they were not drilled in relation to fractures in the
bedrock. He noted that the plan did not state criteria for using these
OMYA's fourth task was to create a computer-generated model of groundwater
conditions and groundwater availability to the fens "pre-quarry and
Smith said that OMYA officials did not say they would assess the site during
quarrying operations. He said the study must take into consideration the
dimensions of the quarry, the amount of water pumped out daily, as well as
increases in pumping and quarry size over time.
The fifth task would be to develop a mitigation plan if the groundwater
modeling indicated potential impact on the fens.
Sixth, OMYA would issue a report on the hydrogeological conditions around
the quarry, and the potential for impact on the fens. It would include
recommendations for long-term monitoring.
In an interview, Smith reiterated his opinion that OMYA was "on the right
track, but they need more detail." He said that if they answer his questions
about projected hydrogeologic conditions during active quarrying, "Then we
can tell what impact they'll have on the fen."