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Widmer Rd 1.,)ceAf cf'VQ.#q-d S~ ~ LJ COpy - PO Box 733 Marlboro, NY 12542 Phone 845-236-7823 Fax 845-236-3911 ENVIRONMENTAL LABWORKS~ INC. NYS DOH #10824 RECEI \lED !'!6,Y 2 9 2003 May """7 .::...,' , 2003 Mr. John Tremper Camo Pollution Control l6l0 RouLe 376 Wappingers Falls, NY 12590 RECE'VED JUN 2 ~ 2003 SUPERVISOR'S OFFICE TOWN OF WAPPINGER rG@fJ?JV Dear Mike, The following are results of the analyses performed on samples from 148 Widmer Road, received at the laboratory on 5/7/03. Sample Location: Time Collected: DaLe Collected: Coilected By: Sink 8:30 am 5/7 /03 JLT PARAMETER RESULTS MAX. CONTAMINANT LEVEL METHOD Chloride 763 mg/L 250 mg/L EPA 325.3 Sodi'..l.m 360 mg/L EPA 200.7 T~e data contained in this report were obtained using EPA or other approved me"Chodologies. The outside laboratory used NYSDOH 11216 is NYS ELAP certified for :.hese analyses. I: you have any questions or require any additional services, please do not hesitate to contact us at 845-236-7823. T~~CN~ ",\"thony J. Falco Laboratory Director ... --....- - ,._ ,~../.'.. >I, I............. " INVESTIGATION GUIDELINES FOR POTENTIAL ROAD SALT CONTAMINATION OF GROUND WATER SUPPLY SOURCES TOWN OF WAPPINGER FALLS Prepared by: Thomas P. Cusack, Senior Associate LJ COpy LEGGETTE, BRASHEARS & GRAHAM, INC. 126 Monroe Turnpike Trumbull, CT 06611 Telephone: (203) 767-0288 Environmental Concerns Road salt can affect the environment through a number of pathways. As described above, it can enter the environment from the storage facilities. Dissolved road salts can also, enter the environment through normal application (streets, sidewalks) and through disposal of waste snow. Plowing and splashing generally concentrate salt deposits along the pavement and shoulders. Vehicular movement also disperses the snow and salt, generally farther from their initial source (Seawall, 1998). Runoff resulting from any of these non-point sources can enter streams or the underlying ground water. This runoff, which contains concentrated' levels of sodium chloride, can have a negative impact on plants and wildlife. Studies have shown that approximately 55 percent of road salt chlorides are transported in surface runoff and the remaining 45 percent infiltrates through soils into the underlying aquifer (Wegner, 2001). In the New York City watersheds, groundwater is a significant contributor to streams. Most soil and vegetation damage occurs within 60 feet of the road with the greatest damage close to the pavement (USRoads, 1997). A study conducted in Canada has shown that road salts can affect sensitive vegetation 150 feet from a treated roadside edge (Environmental News Service, 2000). An LBG study of Rockland County found the biggest factor affecting the chloride content of ground water in the County was the winter use of salt on roads for de-icing. This conclusion was especially evident along the New York State Thruway and Garden State Parkway. Damage to vegetation in buffer areas between roads and watercourses limits natural filtering and retention. As a result, surface runoff can enter the ground water sources and reservoirs with little effort. As previously described, the most effective management practices to reduce impacts to the environment include better storage of the road salts, trained operators, reduce losses during transfers and employing stormwater and washwater management to minimize any potential release. A general rule is to keep the facility clean. Salt should be swept from equipment and flooring after handling (delivery, loading) and placed back under cover. This will minimize brine runoff and keep loose salt from blowing away. Keeping the salt dry is another method of prevention. Where possible, unloading and loading of the trucks should be conducted within the LEGGETTE, BRASHEARS & GRAHAM, INc. -2- enclosed storage facility. Restricting handling of the salt will also prevent the sand particles from breaking down to finer particles. Fine particles are susceptible to becoming airborne or washed away. Potable Water Supplies Areas with the greatest risk of being impacted by road salt application are potable supply wells that are shallow and/or have been completed in a permeable formation (i.e., sand and gravel). Potable wells located within a recharge area in close proximity to major roads and highways that contribute direct runoff are also susceptible to salt contamination. Because road salts are highly soluble, any impacted runoff that infiltrates a high-risk well can potentially impact the water quality from that well. Elevated concentrations of sodium and cWoride in ground water are most common from deicing road salt and disposal of brine in underground septic systems from water softeners. LBG has found that cWoride concentrations in affected wells have the highest concentration of cWoride at the middle of the winter season following salt application of roads and notable decreases during periods of non-application of road salt. Although there has been no link between road salt application and adverse human health, road salts can affect the taste of ground water from wells. A domestic water supplY-IDay become undrinkable because of taste, sodium and cWoride are not known to cause harm to humans (As yet, the association of sodium intake from drinking water with hypertension has not been proved). Sodium and cWoride occur naturally in all ground water at relatively low concentrations. The maximum concentration level (MCL) required by the New York State Department of Health is 250 mg/1 (milligrams per liter) for chloride and 270 mg/1 for sodium. Individuals with claims that road salt application has contaminated their domestic well should be investigated immediately. Roads located within a 1,000 feet of the impacted domestic well should be investigated to determine the areal extent of sand versus road salt application. A survey of water softness treatment (resulting in generating brine) of the impacted .well and neighboring wells should be conducted to determine if the claim is a result of brine discharge in underground septic systems from water softness or from road salt application. Ground water quality from the affected well should be monitored on a monthly basis (preferably between September to May) for sodium and cWoride to indicate any significant increase in sodium/cWoride concentration following application of salt on roads in the winter. Collecting samples prior to and following the winter season would establish the normal background concentrations of the sodium and cWoride. Treatment of water supplies for high sodium and cWoride concentrations is usually cost prohibitive. Mitigation alternatives to consider if the application of road salt by the Town is directly impacting a domestic water supply includes significantly reducing the salt application to the roads in the immediate area of the affected well; using only sand without any deicing agents to the roads in the vicinity of the affected welles) during ice/snow conditions; using alternative deicing chemicals (i.e., CMA) in the immediate vicinity of the impacted well and possibly extending a no-salt application to roads within 1,000-1,500 feet of the affected well. Additional LEGGETTE, BRASHEARS & GRAHAM, INc. -3- consideration would include completing a replacement well for the claimant with a minimum of 200 feet of casing. This deep casing would seal off shallow water-bearing fractures in the bedrock that are likely to become contaminated with elevated sodium/chloride from road salt application. Deeper water-bearing fractures greater than 200 feet are less likely to be impacted by the salting applications, but this approach is by no means a sure remedy. H:\WAPPINER\road salt guidelines. doc LEGGETTE, BRASHEARS & GRAHAM, INC.