July 5, 2005
Honorable Members of the Town of New Castle ZBA
200 South Greeley Avenue
Chappaqua, NY 10514
Re: Application of the Legion of Christ, Inc. for a Women’s Formation Center,
Rte. 128, New Castle, NY
Honorable Members,
On behalf of the Croton Watershed Clean Water Coalition, Inc. (CWCWC), I would like to thank you for this opportunity to comment on the above application.
CWCWC is a coalition of over 50 groups throughout New York City, Westchester and Putnam Counties whose overriding purpose is to protect the Croton watershed waterbodies, including its reservoirs from being polluted due to ill-conceived development.
Croton reservoirs supply 10% 0f the area’s needs (i.e., NYC and its Greater Metropolitan Area), and up to 30 % in times of drought. Croton water is high quality. It should not be allowed to deteriorate, particularly in view of the precarious states of both the Catskill and Delaware supplies. For example, the Catskill system that supplies up to 30% of the area’s needs is due to be taken off-line for repairs in 2007. Furthermore, an ongoing 40 million gallon per day (mgd) leak in the Delaware aqueduct that provides up to 60% of the water supply will eventually have to be closed down for remediation, the extent and duration of which are still unknown. Taken together, these three watersheds supply high quality drinking water to 9 million people, over half of New York State.
Looking ahead, therefore, it is clear that reliance on Croton water will have to increase, and that it should be protected to the fullest extent possible.
The Legionaries of Christ (LOC) Proposal
CWCWC understands that the proposal for the Mater Ecclesiae Women’s Formation Center (WFC) is the most recent in an evolving series. We also understand that the WFC would involve a total of 240 participants including 140 permanent residents.
Under this plan, an additional 17.5 acres (18% 0f the site) will be developed, making a total of 33.38 developed acres out of the overall total 96.38 acres. Approximately half (8.4 acres) of the 17.5 acres lies within an area of slopes that are 15% and above.
The proposal includes 3 tennis courts, 6 basketball courts and a swimming pool, all within a site that is also heavily wooded.
Potential Environmental Impacts
Construction of the proposed facilities will require the blasting and removal of 14,000 cubic yards of rock and the destruction of forested land. The applicant will have to be careful not to disturb the configuration of the underlying aquifer on which the neighbors depend for their well water.
Stormwater runoff from the proposed development will impact an offsite stream that is tributary to the Kisco River that flows into the New Croton Reservoir. According to the Project Summary (page II-25): “A perennial stream exits the Site to the west through a culvert under N.Y. Route 128, and flows north along this road as an unnamed NYSDEC Class D sub-tributary of the Kisco River, a tributary of the New Croton Reservoir. Surface water runoff from the southern half of the property drains to this stream, which discharged to the Kisco River approximately two miles from the Site. Runoff from the northern half of the property drains northwest toward Roseholm Place and N.Y. Route 128, and then joins this same stream west of N.Y. Route 128. There are no NYSDEC-regulated wetlands, water bodies or watercourses on or adjacent to the Site.”
According to a study made by NYSDEC in conjunction with the NYC Department of Environmental Protection (Nonpoint Source Implementation of the Phase II TMDLs, April 2001) the New Croton Reservoir needs a 2,983lb annual reduction in phosphorus in order to be in compliance with the regulations for unfiltered sources of drinking water. The Town of New Castle contributes 30% of this phosphorus, outdone only by Yorktown that contributes 33%. The study also shows that 85% of phosphorus that enters the reservoirs is carried by stormwater; the remainder originates in point sources such as wastewater treatment plants.
Phosphorus promotes the growth of algae blooms that can have detrimental effects on water quality, such as causing odor and color problems, and the need for excessive use of disinfectants such as chlorine. Blue-green algae, in particular, contain toxins, some of which are deemed carcinogenic. (see, for example, a June 25, 2005 article in the Journal News: “Summer, and drinking water concerns bloom”, by Robert Liebman, chairman of the Mt. Kisco Conservation Advisory Council). It is a known fact that as little as one pound of phosphorus can promote the growth of 113 pounds of algae. Therefore, it is of vital concern not to allow any increase of phosphorus in the New Croton Reservoir. On the contrary, each municipality that is responsible for excess phosphorus entering the reservoir should seek to reduce it according to the amounts specified in the afore-mentioned study.
Other pollutants of concern, in addition to the usual list that includes TSS, TN, TKN, nitrites and nitrates, may be found in the 2001 NYS Stormwater Management Design Manual. This is the Manual that must be used in conjunction with the Phase II stormwater regulations, to replace DEC’s 1993 Manual: Reducing the Impacts of Stormwater Runoff from New Development, that the applicant is still, mistakenly, using. The pollutants of concern include copper, lead, zinc, biological oxygen demand, chemical oxygen demand, polycyclic aromatic hydrocarbons (PAHs), oil and grease, fecal coliform, fecal strep, and chloride (from snowmelt). These are listed in Table 2-1, page 2-3 of the 2001 Manual.
Discussion of the Applicant’s Plan for Mitigating Environmental Impacts
1. Erosion and Sediment Control Plan
The possibility of pollutants accessing the Kisco River tributary is of particular concern during the construction phase. Indeed, the US Environmental Protection Agency (EPA) has documented that during the construction phase, “Sediment runoff rates from construction are typically 10 to 20 times greater than those from agricultural lands, and 1,000 to 2,000 times greater than those from forest lands. During a short period of time, construction activity can contribute more sediment to streams than can be deposited over several decades, causing physical and biological harm to our Nation’s waters.” (EPA – Storm Water Phase II Final Rule – Small Construction Program Overview, January 2000, Fact Sheet 3.0). The destruction of much of the existing forest on the WFC site to make room for the new construction will have to be carefully mitigated.
The Phase II NYSDEC SPDES General Permit for Stormwater Discharges from Construction Activity, Permit No. GP-02-01 regulates disturbances that are equal or greater than 1 acre. In this case, over 17 acres will be disturbed. In such cases, an Erosion & Sediment Control Plan (ESCP) has to be developed by the applicant. If the action is located in a TMDL watershed discharging to a 303(d) listed impaired waterbody, then the applicant has to develop a full Storm Water Pollution Prevention Plan that complies with the TMDL requirements of the impaired waterbody.
The ESCP for the WFC, as presented in the FEIS, appears to lack essential components. For example, it is not clear whether the applicant has modified the size, design and locations of the various Management Practices to take into account the change in design from the previous proposals. The applicant proposes “The installation of erosion and sedimentation control devices in accordance with the Westchester Best Management Practices Manual for Erosion and Sediment Control (1991)”, according to Page II-24 of the Project Summary, June 10, 2005. However, EPA states that the technical standards to be followed for erosion and sediment control are described in New York Standards and Specifications for Erosion and Sediment Control, previously the New York Guidelines for Urban Erosion & Sediment Control (4th printing, 1997). The applicant should be using the specifications in the later, far more up-to-date manual.
2. Stormwater Pollution Prevention Plan
Under the heading “Site Character”, page III-14 of the Introduction, June 10, 2005, the applicant describes the site as follows: “The parcel consists of a complex mosaic of micro-environments ranging from steep slopes littered with falling rock debris to swampy wetlands to well-drained knolls and valleys.”
The applicant uses the so-called “Simple Method” for the critically important computation of the change in pollutant loads coming from the site as the result of the proposed development. CWCWC maintains that the Simple Method cannot do justice to such a complex array of land conditions and that, at the very least, mid-range models should be used. Our reservations are borne out by the opinions of experts. For example, “The simple method provides a general planning estimate of likely storm pollutant export from areas at the scale of a development site, catchment or subwatershed. More sophisticated modeling may be needed to analyze larger and more complex drainages. In addition, the Simple Method only estimates pollutant loads generated during storm events…” (NYS Stormwater Management Design Manual, October 2001, page A-6). Again, “While simple methods provide for a rapid means of identifying critical areas with minimal effort and data requirements, they rely in general on large-scale aggregation and neglect important features of small patches of land (emphasis added)…simple methods… provide only rough estimates of sediment and pollutant loading and have limited predictive capability.” (Predicting Pollutant Loading Through the Use of Models, November 1994, page 1 – prepared by NYSDEC and NYS Soil and Water Conservation Committee).
The Simple Method used by the applicant can predict changes in annual pollutant loads or changes in pollutant loads from individual storms. However, given the importance of the New Croton Reservoir for the region’s water supply, more detailed predictions would be desirable. Also, rather than using nationwide average values (i.e. National Urban Runoff Program – NURP values) for the pollutant loads generated by the site in its present undisturbed state, it would be desirable to actually measure those values at the site.
Mid-range programs that are widely used include SLAMM (the Source Loading and Management Model) and P8-UCM (the Urban Catchment Model).
SLAMM realistically estimates flows and pollutant discharges under a wide variety of source conditions and control practices that include detention ponds, infiltration devices, grass swales, porous pavements and others. It can evaluate stormwater conditions arising from the more common small rains in addition to large storms.
P8-UCM enables the user to predict monthly or continuous pollutant loads, and stormwater management practices removal efficiencies.
A model that includes an evaluation of snowmelt would also be desirable since chlorides from the application of salt are a growing concern for the reservoir.
As the operator of a regulated small MS4 (Municipal Separate Storm Sewer System), the Town of New Castle has to make sure that construction activities within its jurisdiction comply with Measures #4 and 5 of the six “minimum control measures” promulgated under GP-02-02 of the Phase II EPA regulations (see, for example, EPA Storm Water Phase II Final Rule, Fact Sheet 2.0). Under Measure #4, “An MS4 must, at a minimum, develop, implement and enforce a program to reduce pollutants in any stormwater runoff to the small MS4 from construction activities that result in a land disturbance equal or larger than one acre.” Under Measure #5, “An MS4 must, at a minimum, develop, implement and enforce a program to address stormwater runoff from new development and redevelopment projects that disturb one acre or more.”
3. Sewage Disposal
The estimate of 75 gallons per day (gpd) of water usage per person seems low. A widely accepted number is 100 gpd per person. In addition, a swimming pool is being proposed and a restaurant on the premises. Both are large consumers of water.
There appears to be no possibility for the disposal of sewage offsite. However, the site itself, because of the prevalence of steep slopes and minimal depth to bedrock presents great difficulties for local disposal of sewage.
The applicant proposes to first treat the sewage onsite before discharging to the sub-soil. The treatment will consist of “two primary clarifiers, a bioreactor with UV disinfection and microfiltration. Following this treatment, the effluent will be dispersed to a meadow via a sub-surface drip system
CWCWC would like to have information regarding the use of such systems in the Croton Watershed. The only examples provided by the engineering firm (Malcolm Pirnie) were two from Wisconsin and one from Missouri. Because of the lack of experience on the use of this system in the Croton Watershed, we urge that it undergo pilot testing under a variety of weather conditions prior to final installation.
In conclusion, CWCWC again thanks this Honorable Board for the opportunity to comment.
Respectfully submitted,
Marian H. Rose, Ph.D.
President, CWCWC
