FEIS D-Malcolm Pirnie Letter and Leggette Brashears & Graham Response

Appendix D Malcolm Pirnie Letter and Leggette, Brashears, & Graham Response

JOHN NASO, JR. WILLIAM K. BECKMAN DAN C. BUZEA J. KEVIN POWERS FRANK J. GETCHELL CHARLES W. KREITLER JEFFREY B. LENNOX W. JOHN SEIFERT, JR. DAVID A. WILEY ROBERT F. GOOD, JR. TIMOTHY L. KENYON THOMAS P. CUSACK DAVID B. TERRY

MATTHEW P. PERAMAKI ____________________ R. G. SLAYBACK JOHN B. ASHWORTH

LEGGETTE, BRASHEARS & GRAHAM, INC.

PROFESSIONAL GROUND-WATER AND ENVIRONMENTAL ENGINEERING SERVICES

4 RESEARCH DRIVE, SUITE 301

SHELTON, CT 06484 203-929-8555

FAX 203-926-9140 www.lbgweb.comwww.lbgweb.com

JOHN M. BENVEGNA JOHN L. BOGNAR

KIMBERLY R. BLOMKER JORMA WEBER

JOSEPH W. STANDEN, JR. MICHAEL A. MANOLAKAS

JAMES A. BEACH WILLIAM P. PREHODA

JEFFREY M. TROMMER DAVID S. HUME

BRUCE K. DARLING KAREN B. DESTEFANIS

JEFFREY T. SCHICK KENNETH D. TAYLOR

ROBERT M. ROHLFS WILLIAM G. STEIN

JOHN W. NELSON WILLIAM H. AVERY

ROY SILBERSTEIN PAUL M. JOBMANN

BRIAN C. KIMPEL JOHN R. DIEGO

MICHAEL SUSCA KEITH J. SHORTSLEEVE

BRAD CROSS MITCHELL KANNENBERG

CONNECTICUT• LOUISIANA • OHIO • ILLINOIS • SOUTH DAKOTA • PENNSYLVANIA • FLORIDA • NEW JERSEY • MINNESOTA

TEXAS• WISCONSIN • NEW YORK • MISSOURI

June 18, 2007 Mr. Martin Lonstein, Planning Board Chair Town of Wawarsing Town Hall 108 Canal Street Ellenville, NY 12428 Dear Mr. Lonstein: Leggette, Brashears & Graham, Inc. (LBG) is providing responses to comments on the Mahamudra Buddhist Hermitage DEIS made by Malcolm Pirnie Inc. (MPI) in a March 20, 2007 letter. MPI was retained by the Town of Wawarsing Planning Board to review the hydrogeology aspects of the DEIS as a response to the concerns by the consultants for the Cragsmoor Association (CA). This letter addresses the MPI request for additional data and clarifications. Request No. 1

“a map showing the location of the discharge location of water pumped during the

drawdown tests”

Response: The discharge water from Well 1 and Well 2 was diverted through a 3-inch fire hose to a

drainage basin on the western portion of the property. The well discharge locations were

presented on figure 1 (attached) of the report entitled “Water-Supply Testing, Proposed

Mahamudra Buddhist Hermitage, Cragsmoor, New York”. Discharge for Well 2 was directed to

the northern location and discharge for Well 1 was directed to the southern location. These

locations were agreed upon by LBG and the CA’s consultant prior to the initiation of the aquifer

tests.

Request No. 2

“the dimensions and locations of the recharge area to the Hermitage wells”

www.lbgweb.com

Mr. Martin Lonstein -2- June 18, 2007

Response:

The Dharmakaya Water Supply Report discussed the recharge capabilities of the area,

however, a map was not provided due to the nature of bedrock aquifers. Figure 1 shows the

property boundary and the estimated upland watershed area that provides recharge to the

property. The dimensions and locations of source-water or recharge areas for bedrock wells are

greatly affected by fracture geometry, orientation and density. These factors make it impossible

to accurately delineate recharge areas even in situations where the general fracture patterns are

reasonably understood. Because of these difficulties, it is generally assumed that the recharge

area for an individual well tends to mimic the land surface topography. This is a reasonable

assumption on a regional scale or where fracture density is great enough that the system acts as a

porous-media aquifer. However, on a local scale (as in the case of the Hermitage Wells, see

figure 1 in DEIS) where fractures cross topographic divides; the assumption can produce results

that are not technically defensible. Therefore, definitive recharge areas for the Hermitage Wells

have not been delineated.

Request No. 3

“the groundwater flow direction”

Response:

The Dharmakaya Water Study contained an extensive discussion on the fractures in the

area’s bedrock and the role they play in the proposed Hermitage water supply which includes

ground-water flow process and its impact on the area. Because the ground-water flow in bedrock

aquifers is strongly influenced by fractures in the rock formation, it must be understood that a

water-level configuration map for such aquifers is, at best, only an approximation of the actual

water-level configuration, especially if the map is constructed from a network of monitor wells

tapping fractures that are not interconnected. With this in mind, LBG constructed a water-level

configuration map (figure 2) using depth-to-water and land-surface elevation information for the

wells monitored during the aquifer tests completed in 2005. Land-surface elevation data were

estimated from a USGS topographic map. Figure 2 shows that ground water in the area flows

from north to southeast (generally mimicking the surface topography).


Request No. 4

“the zone of influence of the Hermitage wells”

Response:

As explained in the previous response, the bedrock nature of the aquifer strongly

influences the extent and potential impacts that may be created by the Dharmakaya project. This

is fully explained in the Dharmakaya Water Study. Therefore, because the Hermitage wells are

completed in a fracture-controlled bedrock aquifer, no clearly defined zone of influence can be

delineated. Results from the aquifer test showed that only two of the ten offsite wells (49 and

71 Old Inn Road) monitored during the aquifer tests showed discernable drawdown interference

effects from pumping of the onsite wells. Figure 1 shows that the wells monitored at 49 and

71 Old Inn Road were located approximately 840 feet and 500 feet to the north and east,

respectively, of Well 2 (the nearest onsite production well). However, because of the fractured

nature of bedrock systems, it cannot be concluded that the area of influence would be radial in

nature or that wells completed in close proximity to the impacted wells would also be impacted.

For example, no discernable interference effects were observed in the well located at 95 Old Inn

Road during the Well 2 aquifer test, even though it is located closer to Well 2 than a well (49 Old

Inn Road) impacted by pumping during the test.

It has been argued by others that aquifer parameters developed from the pumping tests

should be used to estimate the area of influence of the Cragsmoor wells. The use of aquifer

parameters to anticipate interference of the wells completed in bedrock, as proposed, is not

technically appropriate. As discussed above, ground-water flow in bedrock aquifers is strongly

influenced by fractures in the rock formation. Consequently, the conventional well-flow

equations, developed for isotropic homogeneous aquifers of infinite aerial extent, do not

adequately describe the flow in fractured rock, except in rare instances where the fracture density

is great enough that the system acts as a porous-media aquifer. This expectation is not the case

in the study area.

Another complicating factor when attempting to use aquifer parameters in this manner is

that the extent of the fracture pattern is typically unknown. This may lead to instances where

attempts are made to calculate regional aquifer parameters (so that long-term yield and well

interference effects can be estimated) from a network of monitor wells tapping fractures that are


not interconnected. If the aquifer parameters calculated for the above-described monitor well

network were used to estimate long-term well yield, the results would be grossly inaccurate.

Added to this complexity is the fact that the theory of fluid flow in fractured rock is not as

established as that in porous media. Because of this, contradictory results sometimes occur when

analyzing drawdown data, even if the fracture pattern is reasonably understood (Kruseman and

Ridder, “Analysis and Evaluation of Pumping Test Data”, International Institute for Land

Reclamation and Improvement, The Netherlands, 1990). Therefore, the resulting regional

aquifer parameters would once again produce inaccurate estimates of the wells’ area of

influence.

Even if the wells proposed for testing were located in a sand and gravel aquifer

(i.e., essentially treatable as a homogeneous isotropic aquifers of infinite areal extent) rather than

a bedrock aquifer, the methodology proposed would be inappropriate to estimate potential well

interference. The analytical equations utilized to estimate aquifer parameters do not account for

impacts due to aquifer boundaries, leakage to and from surface water bodies, variations in

aquifer thickness, or the dewatering of significant shallow fractures. All of these

unaccounted-for parameters help determine the amount of replenishment available to a well.

Therefore, even under the best conditions, the use of the aquifer parameters (generated from the

analytical equations) can produce results that are not technically defensible.

Request No. 5

“a discussion of the impacts of operational pumping rates of the Heritage wells and the

area’s recharge rates on wells downhill from the Hermitage site, including potential impacts to

wells not monitored (shallow wells as well as inaccessible ones)”

Response:

The Dharmakaya Water Study did discuss the fact that there should be no impacts on

neighboring wells with the operational pumping rates for the Hermitage. One of the

downgradient wells, 19 Cragsmoor Road, was a shallow well at 22 btoc. This well did not show

any impacts during the well testing program and would be representative of others in the area.

Water-demand estimates provided by Chas. H. Sells Inc. indicated that the total potable water

demand for the project for the reduced impact layout is 8,496 gpd, or 5.9 gpm. In November


2005, a 24-hour aquifer test was completed on Well 2. During the test, Well 2 was pumped at

25 gpm (or over four times the anticipated demand). Results from the aquifer test showed that

the offsite wells at 49 and 71 Old Inn Road were the only offsite wells that showed discernible

drawdown interference effects from pumping. The maximum observed drawdowns at the wells

at 49 and 71 Old Inn Road were 2.6 feet and 3.9 feet, respectively. The wells at 49 and 71 Old

Inn Road are located approximately 850 feet and 510 feet from Well 2, respectively. The

drawdown observed in these wells under normal operation of the onsite wells (12-hour daily

pumping cycles at 5.9 gpm- approximately 24 percent of the tested production) would be

considerably less. This, coupled with the fact that any potential impact would diminish with

distance and that no impact was observed in the deep bedrock wells located on Clarks Road and

Cragsmoor Road (located over 1,200 feet away), suggests that the onsite wells will not impact

shallow wells downgradient of the site. The applicant has agreed to monitor the two wells

impacted during testing for a two-year period following full build-out of the proposed project.

This additional monitoring will determine significant impacts, if any, under normal operation of

the proposed well source.

Although the locations of the well recharge areas have not been delineated, the size of the

recharge area is estimated to be approximately 16 acres (less than 18 percent of the 91-acre

parcel). The size of the recharge area under average conditions was estimated by calculating the

radius that has a volume equal to the volume of water pumped over one year and a height equal

to the annual recharge rate. The radius was then used to calculate the recharge area. The only

parameters used for this estimate are an average annual recharge and the well field pumping rate.

Therefore, this approximation does not incorporate fracture geometry, location, or density or

other variables that may influence the size of the recharge area. The estimated recharge area for

each Hermitage well at 5.9 gpm (projected average demand) with an average recharge to bedrock

of 7 inches per year (the more conservative USGS annual recharge estimate presented in the

DEIS) was calculated using the following equation:

A= (Q*268,383/R)* /43,560 Where: A = Estimated Recharge Area (in acres) Q = pumping rate (gpm) R = average annual recharge to bedrock (inches)

Note: The equation was derived using the formulas for the volume of a cylinder and the area of a circle.


This analysis shows that the recharge potential to the property significantly exceeds the

estimated project demand. Based on this result, it is concluded that there would be no

discernable impact to the shallow wells downgradient of the Hermitage site resulting from

normal use and operation of the bedrock wells even if on-site recharge of wastewater is not

included in the recharge analysis. If the on-site recharge of wastewater were include in the

analysis (assuming 15 percent consumptive use), the total consumptive use (or water lost from

the ground-water system) would be approximately 0.9 gpm, resulting in a recharge area of

approximately 2.5 acres or (approximately 3 percent of the parcel).

Request No. 6

“a discussion of the effects of drought conditions on the water supply”

Response:

A discuss of drought conditions was contained in the Dharmakaya Water Study under

the “Groundwater Balance” section. In addition, the data from the two aquifer test suggests that,

in their present condition, Wells 1 and 2 can both be pumped at twice the daily demand, which

would be 12 gpm for at least 72-hours in the case of Well 1 and 12 gpm for at lest 24-hours in

the case of Well 2. To evaluate the maximum withdrawal that can be maintained by each well

during an extended dry period, the available drawdown was projected for 180 days of continuous

pumping at 50 gpm and 25 gpm for Wells 1 and 2, respectively. The projected drawdown in

Wells 1 and 2 were calculated to be approximately 55.4 feet and 33 feet, respectively. The pump

setting in each well was 350 ft btoc. Based on these figures, the estimated available drawdown

in Wells 1 and 2 after 180 days of constant pumping would be approximately 194 feet and

206 feet (discounting 100 feet above each of the pumps for a safety factor). This analysis is not

intended to imply that the test rates can be sustained for 180 consecutive days, especially

considering that the wells are completed in bedrock where fracture dewatering can occur. This

simple extrapolation, does suggest, however, that Wells 1 and 2 should be able to withdraw the

average daily demand of 5.9 gpm during drought conditions.


Concerns Raised By Cragsmoor Association Consultants

The aquifer did not recover to at least 90 percent of the drawdown within 24 hours during the recovery portion the aquifer tests, as per NYSDOH regulations. Which suggest that the test rate may not be sustainable for an extended period of time.

As stated by the Planning Board’s consultant, “Taking into consideration the fact that the applicant stressed the aquifer at approximately seven times the daily demand for 72 hours and the on-site recharge greatly exceed the seven gpm demand, the loss of storage should not affect the water system’s ability to meet the seven gpm demand”. Were enough homes monitored to the north or the property to adequately protect the

homes in the area?

The NYSDOH requires an applicant to monitor 6 to 10 homes surrounding the site; ten were monitored during the tests on the Hermitage Wells. In addition, the Planning Board’s consultant concluded that the aquifer tests were conducted in accordance with the NYDOH regulations.

Concerns related to offsite pumping impacts, the water supply system’s ability to meet

system demands during and drought and the use of aquifer parameter to evaluated area of

influence have been addressed above and by the Planning Board’s consultant in the

March 25, 2007 letter.

In the summary of their recommendations, MP requested that the applicant measure the

pump setting at 49 Old Inn Road and the pump setting and depth of the well at 71 Old Inn Road.

During the well study, LBG attempted to obtain the requested data but was unable to do so

because of the well completion at each of the locations. We also attempted to obtain the

requested information from other sources (Ulster County Health Department and the individual

homeowners). In each case, the wells are so old that no records exist. Additionally, the

homeowners do not have any information on the wells, including the name of the original well

driller. Because of the type of well completion at each of the locations, it would be difficult to

obtain the requested data without potentially compromising or damaging the wells and/or pumps.

Thus, it is LBG opinion that any potential information gained by collecting this data is

outweighed by potential risk of collecting the data. Especially considering that, both of the wells

would be included in the proposed monitoring program and any potential impacts related to

withdrawals from the applicant’s water-supply system would be noted prior to adversely

impacting the homeowner.


Please contact me if you have any questions or concerns at (203) 929-8555.

Very truly yours, LEGGETTE, BRASHEARS & GRAHAM, INC.

Kenneth Taylor Associate

Reviewed by: R.G. Slayback, CPG Senior Consultant KT:nv Enclosures cc: Mary Lou Christiana, Esq.-Town of Wawarsing Planning Board Attorney David Stolman – Frederick P. Clark Associates, Inc Susan Fasnacht – Chas. H. Sells, Inc. Daniel St. Germain – Malcolm Pirnie H:\Buddist Hermitage\DEIS Comment Letter - revised III.doc

FEIS D-Malcolm Pirnie Letter and Leggette Brashears & Graham Response

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