Safe Drinking Water Program. Surface Water Identification Protocol (SWIP) May 17, 2016 Tom Yeager, P.G.

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1 Safe Drinking Water Program Surface Water Identification Protocol (SWIP) May 17, 2016 Tom Yeager, P.G.

2 PA Safe Drinking Water Program SWIP is used to determine if groundwater sources are directly influenced by surface water. GUDI Groundwater Under Direct Influence

3 PA Safe Drinking Water Program SWIP is designed to protect PUBLIC HEALTH Section of the Safe Drinking Water Regulations states that A public water system shall provide adequate treatment to reliably protect users from the adverse health effects of microbiological contaminants, including pathogenic bacteria, viruses and protozoan cysts. *Does not assess adverse impacts/quantity issues

4 Why is SWIP important? Giardia lamblia (Giardiasis) Criptosporidium parvum (Cryptosporidiosis) Resistant to disinfection Outbreaks Must Filter (SW & GUDI)

5 Groundwater Under Direct Influence (GUDI) Section defines GUDI as Any water beneath the surface of the ground with the presence of insects or other macroorganisms, algae, organic debris or large diameter pathogens such as Giardia lamblia and Crytosporidium, or significant and relatively rapid shifts in water characteristics such as turbidity, temperature, conductivity or ph which closely correlate to climatological or surface water conditions

6 Surface Water Identification Protocol SWIP consists of three stages: Screening to determine questionable sources Wells-aquifer geology, water level and proximity to surface water Springs and infiltration galleries-automatically questionable Special six-month monitoring on questionable sources Microscopic Particulate Analysis (MPA) for final surface influence determination

7 SWIP Screening Criteria IS THE WELL LOCATED YES NO in a carbonate aquifer with static water elevation <or=100 feet below ground level? YES NO in an unconfined aquifer with static water elevation <or=50 feet below ground level?

8 SWIP Screening Criteria Continued: IS THE WELL LOCATED YES NO in a confined aquifer which is located <or=50 feet below ground level? YES NO <or=200 feet from a surface water body? (Does not apply to confined or unconfined with SWL>100 ft bgl)

9 Surface Water Identification Protocol Well = YES, What s next? Submit a SWIP Monitoring Plan for Approval Reviewed and approved by Regional Geologist Monitoring should commence within 3 months of approval

10 SWIP Monitoring Plan Guidelines

11 SWIP Monitoring Plan Guidelines

12 SWIP Sampling Water system must take a daily raw water sample from the approved sampling point for: turbidity, ph, specific conductance and temperature Daily measurements pumping rate and water level Weekly total coliform and E. coli sampling (certified laboratory)

13 Climatological and Surface Water Monitoring Precipitation-Daily recordings (National Weather Service-975 Gauges) If local rain gauge is not available (<20 miles) operator must install and maintain one

14 Climatological and Surface Water Monitoring Local Surface Water conditions-daily recordings of stage or flow Typically utilize USGS Gauge or install staff gauge

15 SWIP Monthly Reporting

16 SWIP Statistical Analysis Evaluate the relationship between PRECIPITATION and the ph, temp., cond. and Turbidity Correlation Analysis: five day averages run through a multiple regression model Model generates a strength of correlation: -.40 to +.40 Weak Relationship -.40 to -.75 and +.40 to+.75 Moderate Relationship -.75 to and +.75 to Strong Relationship

17 MPA-What do we look for?

18 MPA-What do we look for?

19 Microscopic Particulate Analysis (MPA) MPA-identification, sizing and population estimates of microorganisms and organic or inorganic debris found in water Minimum 300 gallons One micrometer filter

20 MPA-What do we look for?

21 HIGH RISK GUDI WELLS WELL CONSTRUCTION-VERY IMPORTANT!

22 HIGH RISK GUDI WELLS WELL CONSTRUCTION DEFICIANCIES

23 LIMESTONE CONSTANTLY CHANGING SWIP Cases Can be re-evaluated at any time based on water quality changes

24 HIGH RISK GUDI WELLS LIMESTONE Complex System

25 Must provide permanent filtration treatment facilities Abandon the unfiltered source Utilize a backup source Interconnect with another water supplier Drill a new well What if my well is GUDI?

26 HIGH RISK GUDI WELLS

27 HIGH RISK GUDI WELLS

28 Summary Prevent outbreaks/protect Public Health Adverse Impacts identified by aquifer test/permitting evaluation Just because a well passes SWIP does not mean you are off the hook for a pass-by flow requirement Conditions change Have a reliable back-up source!

29 DEP SC Region SWIP Contacts

30 Tom Yeager, P.G. Safe Drinking Water Program PA DEP South-central Region