TITLE 5 SOIL EVALUATOR CERTIFICATION TRAINING 310 CMR CMR (3) DETERMINING HIGH GROUNDWATER ELEVATION

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1 TITLE 5 SOIL EVALUATOR CERTIFICATION TRAINING 310 CMR CMR (3) DETERMINING HIGH GROUNDWATER ELEVATION Prepared for: Commonwealth of Massachusetts Department of Environmental Protection By L.A. Spokas, PhD, Stockbridge School of Agriculture University of Massachusetts Amherst Presented by: New England Interstate Water Pollution Control Commission 310 CMR (3) (a) - High Groundwater elevation shall be determined by: (a) soil color using the Munsell system, the abundance, size, and contrast of redoximorphic features, if present; (b) one or more of the following methods may be used to supplement the method in 310 CMR (3)(a) and shall be used when no redoximorphic features are present. 1. Observation of actual water table during times of annual high water table (typically March/April); Known as the wet season approach 2. The use of USGS wells for correlating comparisons in water tables during times when the water table is not at the annual high range

2 2. THE USE OF USGS WELLS FOR CORRELATING COMPARISONS IN WATER TABLES DURING TIMES WHEN THE WATER TABLE IS NOT AT THE ANNUAL HIGH RANGE; Current Conditions for Massachusetts: Groundwater National Water Information System: Web Interface USGS Water Resources Data Category: Geographic Area: Current Conditions Massachusetts These wells are monitored monthly Barnstable County (11 wells) MA-FSW MA-CGW 138 CHATHAM, MA MA-SDW 253 SANDWICH, MA MA-SDW (90MW0063) MA-BHW 198 BOURNE, MA MA-SDW (MW-145S) MA-SDW SANDWICH, MA MA-SDW (MW-126S) MA-BMW 22 BREWSTER, MA MA-WNW 17 WELLFLEET, MA MA-TSW 89 TRURO, MA Berkshire County (2 wells) MA-SJW 58 SHEFFIELD, MA MA-PTW 51 PITTSFIELD, MA Bristol County ( 1 well) MA-SHW 275 SEEKONK, MA Essex County (3 wells) MA-WPW 76 WENHAM, MA MA-NIW 27 NEWBURY, MA MA-HLW 23 HAVERHILL, MA Hampden County (1 well) MA-GLW 6 GRANVILLE, MA Hampshire County (1 well) MA-PDW 23 PELHAM, MA Middlesex County (4 wells) MA-WKW 2 WAYLAND, MA MA-ACW 158 ACTON, MA MA-WAW 38 WAKEFIELD, MA MA-XMW 78 WILMINGTON, MA Norfolk County (4 wells) MA-NNW 27 NORFOLK, MA MA-LKW 14 LAKEVILLE, MA MA-PWW 22 PLYMOUTH, MA MA-D4W 79 DUXBURY, MA Worcester County (2 wells) MA-WSW 26 WEST BOYLSTON, MA MA-PHW 16 PETERSHAM, MA

3 Depth to Water level (ft. below grade) USGS Green Line Historic Daily Mean Blue/red lines current date, shaded area historic range > 90 Percentile < 10 Data Point Monthly median 3. A Department-approved method for determining inland high groundwater elevation as contained in Frimpter (1981) or Frimpter and Belfit (1992).

4 FRIMPTER METHOD An estimate of the high water level at an observation well may be derived by solving the proportion in which the ratio of the potential water level rise at a test site to the potential water level rise at an observation well is equal to the ratio of the water level range at the site to the historic water level range at an observation well in a similar geohydrologic environment. These Terms S h = S c Probable range at the site From Frimpter Graphs Observation well, current depth S r x (Ow c Ow max ) Ow r Observation well maximum high GW Observation Well range the Observation Well

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6 Water-Level Range, In Feet Water-Level Range, In Feet SANDS AND GRAVELS IN VALLEY FLATS A maximum water-level range of 4.2 feet is expected to be equaled or exceeded at about 5% of sites in sand and gravel in valley flats Percentage of sites at which water-level range is equaled or exceeded SANDS AND GRAVELS ON TERRACES A maximum water level range of 10 feet is expected to be equaled or exceeded at about 5% of sites in sand and gravel on terraces Percentage of sites at which water-level range is equaled or exceeded

7 Water-Level Range, In Feet TILL A maximum water level range of 17 feet is expected to be equaled or exceeded at about 5% of sites in till Percentage of sites at which water-level range is equaled or exceeded RANGE OF WATER TABLE ELEVATION FOR A SITE WELL (SR) The Range of Water Table Elevation For a Site Well Will Be Based on the Hydrogeologic Setting of the Well and Will be One of Three Values For a 5% Exceedance Value Till Wells 17 Feet Sand and Gravel Wells on Terraces 10 Feet Sand and Gravel Wells in Valley Flats 4.2 Feet

8 ACTON (ACW) 158 (real-time data since June 2001) Start year of record Land-surface elevation 153 ft, well depth 33.8 ft Lithology - SAND Topographic setting - TERRACE Period of record - HIGH (OWmax) LOW (OWr) 5.40 These Terms S h = S c 10 S r x Probable range at the site From Frimpter Graphs (April 3, 2015) (Ow c Ow max ) OW r 5.40 the Acton Well

9 Water-Level Range, In Feet ACW 158 MEAN DEPTH TO WATER DATE Jan 2015 Feb 2015 Mar 2015 Apr P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P P COUNT MAX MIN SANDS AND GRAVELS ON TERRACES A maximum water level range of 10 feet is expected to be equaled or exceeded at about 5% of sites in sand and gravel on terraces Percentage of sites at which water-level range is equaled or exceeded These Terms S h = 10 Probable range at the site From Frimpter Tables 10 x ( ) 5.40 the Acton Well

10 These Terms S h = x the Acton Well These Terms S h = S h = 2.03

11 These Terms S h = S c Observation well, current depth S r x (Ow c Ow max ) Ow r Observation well maximum high GW Probable range at the site From Frimpter Graphs Observation Well range the Observation Well WAKEFIELD (WAW) 38 (real-time data since July 2001) Start year of record Land-surface elevation 80 ft, well depth 25.5 ft Lithology - SAND Topographic setting - FLAT Period of record - HIGH (OWmax) 2.92 LOW 9.99 (OWr) 6.33

12 Water-Level Range, In Feet WAW38 MEAN DEPTH TO WATER DATE Jan 2015 Feb 2015 Mar 2015 Apr P 6.54 P 6.99 P 5.29 P P 6.54 P 6.99 P 5.33 P P 6.59 P 7.01 P 5.28 P P 6.61 P 6.98 P 5.19 P P 6.62 P 6.96 P 5.25 P P 6.64 P 6.97 P 5.33 P P 6.65 P 6.95 P 5.38 P P 6.67 P 6.94 P 5.43 P P 6.69 P 6.90 P 5.36 P P 6.71 P 6.70 P 5.28 P P 6.72 P 6.16 P 5.34 P P 6.73 P 5.60 P 5.46 P P 6.76 P 5.74 P 5.51 P P 6.76 P 5.69 P 5.55 P P 6.77 P 5.18 P 5.61 P P 6.81 P 5.18 P 5.67 P P 6.82 P 5.18 P 5.68 P P 6.84 P 5.15 P 5.73 P P 6.85 P 5.34 P 5.79 P P 6.88 P 5.49 P 5.76 P COUNT MAX MIN SANDS AND GRAVELS IN VALLEY FLATS A maximum water-level range of 4.2 feet is expected to be equaled or exceeded at about 5% of sites in sand and gravel in valley flats Percentage of sites at which water-level range is equaled or exceeded These Terms S h = x ( ) 6.33 Probable range at the site From Frimpter Tables Water Level (April, ) the Wakefield Well

13 These Terms S h = x Probable range at the site From Frimpter Tables the Wakefield Well These Terms S h = S h = 8.12 the Wakefield Well Site Maximum Site current Probable Range Observation Observation Observation on site well current well max well range Sh = Sc - [ Sr x ( Owc - Owmax) / Owr ]

14 4. A Department-approved method for determining coastal high groundwater elevation which incorporates tidal fluctuation information into use of historical high groundwater data as contained in Frimpter and Belfit (1992) or 5. If the location of the system is affected by tidal cycle, typically within 300 feet of mean high water of the ocean, monitoring the high groundwater elevation over a tidal cycle during a full moon high tide.