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Contact Phone Number 6072728902 for Environmental Associates Ltd.

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  1. General Sampling Quote Requests  for Microscopic Particulate Analysis ( MPA) for groundwater  – Ground Water Under Direct Influence ( GWUDI )  and Biosolids
  2. EPA Method 1623 testing for LT2: for Giardia and Cryptosporidium analysis for the EPA Long Term 2 Surface Water Treatment Rule (LT2ESWTR or LT2 rule).

 

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Environmental Associates Ltd.

24 Oak Brook Dr.
Ithaca, NY 14850

Phone 607-272-8902
FAX 607-256-7092
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( 6072728902 )

LT2ESWTR Source Water Monitoring for Systems Serving At Least 10,000 People Factsheet

WHAT IS THE LT2ESWTR?

 The U.S. Environmental Protection Agency (EPA) published the Long Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR) on January 5, 2006. The LT2ESWTR improves control of microbial pathogens. The LT2ESWTR requires source water monitoring at public water systems (PWSs) that use surface water or ground water under the direct influence of surface water (GWUDI) (i.e., Subpart H PWSs). Based on system size and filtration type, systems need to monitor for Cryptosporidium, E. coli, and turbidity.

WHAT IS THE PURPOSE OF SOURCE WATER MONITORING?

Source water monitoring data will be used to categorize the source water Cryptosporidium concentration into one of four “bin” classifications that have associated treatment requirements. The LT2ESWTR provides other options for systems to comply with the initial source water monitoring requirements:

Submit data from Cryptosporidium samples collected before the system must begin source water monitoring (i.e., Grandfathered), and the data must meets certain requirements.

Filtered systems may skip source water monitoring and commit to provide a total of at least 5.5- log of treatment for Cryptosporidium, equivalent to meeting the treatment requirement of Bin 4. Unfiltered systems skip source water monitoring and commit to provide a total of at least 3-log Cryptosporidium inactivation, which is equal to meeting the treatment requirements for unfiltered systems with a mean Cryptosporidium concentration of greater than 0.01 oocysts/L. Systems that decide to skip monitoring and provide maximum treatment must notify the state in writing.

A second round of source water monitoring will follow 6 years after the system makes its initial bin determination. Grandfathering is not available for the second round of source water monitoring.

 

Note: E. coli and turbidity data may not be grandfathered unless the system is also grandfathering corresponding Cryptosporidium data.

WHAT ARE THE INITIAL SOURCE WATER MONITORING REQUIREMENTS?

 

The source water monitoring requirements of the LT2ESWTR apply to all Subpart H PWSs. You are subject to initial source water monitoring requirements if you do not have existing monitoring data that meets grandfathering requirements. For more information on source water monitoring requirements, see EPA’s Source Water Monitoring Guidance Manual for Public Water Systems for the Final Long Term 2 Enhanced Surface Water Treatment Rule (EPA 815-R06-005 February 2006), available at www.epa.gov/safewater/disinfection/lt2/compliance.html.

Prior to beginning initial source water monitoring, you must submit a sampling schedule that specifies the calendar dates when you will collect the required source water samples. The samples must be evenly spaced throughout the monitoring period (e.g., monthly on the 15th of each month). However, the schedule may be altered to take into account holidays, weekends, or other events. All the samples must be taken within a 5-day window (i.e., you can take the sample up to 2 days before or 2 days after

the date indicated in the schedule). In addition, you must submit a description of the intended sampling location in relation to the source and any treatment processes, as well as a description of any points of chemical addition, and filter backwash recycle.

 

FILTERED SYSTEMS SERVING AT LEAST 10,000 PEOPLE – You must collect Cryptosporidium,

  1. coli and turbidity samples at least monthly for 24 months.

 

UNFILTERED SYSTEMS SERVING AT LEAST 10,000 PEOPLE – You must sample for Cryptosporidium

at least monthly for 24 months.

 

Alternately, you may notify the EPA or the state that you elect not to conduct source water monitoring and commit to providing the maximum treatment of 5.5 log removal or inactivation for filtered systems or 3-log inactivation for unfiltered systems.

WHEN MUST I COMPLY WITH THE MONITORING REQUIREMENTS?

 

The system compliance schedule is based on the population served by your system. A PWS must conduct monitoring based on the requirements of the largest system in the combined distribution system. The interconnected wholesale/consecutive systems relationships have been determined by the state.

 

Systems that serve… > 100,000 people

(Schedule 1) 1

 50,000 to 99,999

people (Schedule 2) 1

 10,000 to 49,999

people (Schedule 3) 1
Submit: Sample Schedule and Sample Location Description July 1, 2006 January 1, 2007 January 1, 2008
Must begin the first round of source water monitoring by… October 2006 April 2007 April 2008
Submit Grandfathered Data (if applicable) December 1, 2006 June 1, 2007 June 1, 2008
Submit Bin Classification (Filtered) or Mean Cryptosporidium Level (Unfiltered) March 2009 September 2009 September 2010
Comply with additional LT2ESWTR treatment technique requirements2 April 1, 2012 October 1, 2012 October 1, 2013
Must begin the second round of source water monitoring by… April 2015 October 2015 October 2016

1 Your schedule is defined by the largest system in your combined distribution system.

2 State may allow up to an additional 2 years for capital improvements to comply with the treatment technique.

 

WHAT IS A BIN CLASSIFICATION?

 

FILTERED SYSTEMS SERVING AT LEAST 10,000 PEOPLE – You will be classified into a “bin” based on the results of your source water monitoring. Your bin classification determines whether further treatment for Cryptosporidium is required. A second round of source water monitoring is required 6 years after your initial bin classification and may affect your bin classification.

 

 

For systems that are:

 Mean Cryptosporidium

Concentration1

  

Bin Classification
…required to monitor for Cryptosporidium < 0.075 oocysts/L Bin 1
from 0.075 to < 1.0 oocysts/L Bin 2
from 1.0 to < 3.0 oocysts/L Bin 3
> 3.0 oocysts/L Bin 4

1 Samples must be analyzed by an approved laboratory and use EPA method 1622 or 1623.

 

ADDITIONAL TREATMENT REQUIREMENTS FOR FILTERED SYSTEMS – Additional treatment is required if the bin classification is a 2, 3, or 4. Refer to the table below for the additional Cryptosporidium treatment requirements.

 

Bin Classification If the system uses the following filtration treatment in full compliance with existing requirements, then the additional Cryptosporidium treatment requirements are…
Conventional filtration treatment (including softening)  

Direct filtration

 Slow sand or diatomaceous earth filtration Alternative filtration technologies
Bin 1 No additional treatment No additional treatment No additional treatment No additional treatment
Bin 2 1-log treatment 1.5-log treatment 1-log treatment (1)
Bin 3 2-log treatment 2.5-log treatment 2-log treatment (2)
Bin 4 2.5-log treatment 3-log treatment 2.5-log treatment (3)
  • As determined by the state such that the total Cryptosporidium removal and inactivation is at least 0-log.
  • As determined by the state such that the total Cryptosporidium removal and inactivation is at least 0-log.
  • As determined by the state such that the total Cryptosporidium removal and inactivation is at least 5-log.

For information on the toolbox options that can be used to achieve additional log removal requirements, see the Long Term 2 Enhanced Surface Water Treatment Rule Toolbox Guidance Manual (draft version anticipated late 2006).

 

UNFILTERED SYSTEMS SERVING AT LEAST 10,000 PEOPLE – You must calculate an arithmetic mean of all Cryptosporidium samples concentrations required. Following completion of the second round of source water monitoring, you must provide a level of inactivation for Cryptosporidium based on the arithmetic mean of your Cryptosporidium sample concentrations.

 

 

For systems that are:

 Mean Cryptosporidium

Concentration1

  

Cryptosporidium inactivation
Unfiltered < 0.01 oocysts/L 2-log
> 0.01 oocysts/L 3-log

1 Samples must be analyzed by an approved laboratory and use EPA method 1622 or 1623.

 

ARE YOU CONSIDERING MAKING A CHANGE TO YOUR DISINFECTION PRACTICES?

 

After completing the initial round of source water monitoring, systems that plan to make a significant change to their disinfection practice must notify the state, develop disinfection profiles, and calculate disinfection benchmarks for Giardia lamblia and viruses. To develop a profile and benchmark, PWSs must monitor at least weekly for a period of 12 consecutive months to determine the total log inactivation for Giardia lamblia and viruses. The disinfection benchmark is an indicator of disinfection effectiveness and depends upon the inactivation of Giardia lamblia or viruses. The benchmark is determined by calculating the average daily inactivation value for each of 12 consecutive months. The lowest monthly average becomes the disinfection benchmark. If the PWS has data from more than 1 year, the benchmark is the average of the lowest monthly average value for each of the years. A PWS may use grandfathered data that is substantially equivalent to develop the disinfection profiles for Giardia lamblia and viruses. The Long Term 1 Enhanced Surface Water Treatment Rule (LT1ESWTR) Disinfection Profiling and Benchmarking Technical Guidance Manual (EPA 816-R-03-004, May 2003), provides guidance for developing a disinfection profile and benchmark. EPA has developed two tools for systems to determine their disinfection profile and calculate the benchmark at the following website: http://www.epa.gov/safewater/mdbp/lt1eswtr.html.

ADDITIONAL GUIDANCE MATERIALS

 

The following guidance document addresses the source water monitoring requirements for the LT2ESWTR:

 

Source Water Monitoring Guidance Manual for Public Water Systems for the Final Long Term 2 Enhanced Surface Water Treatment Rule (EPA 815-R06-005 February 2006) – Provides surface water systems, laboratories, states, and Tribes with a review of the source water monitoring provisions. The source water monitoring guidance manual provides direction to the systems on how, where and when to monitor, how to report the data, how to submit “grandfathered” data (e.g., previously collected data), and how the data can be evaluated and used to determine risk bin classification.

 

For additional guidance on implementing the LT2ESWTR, you may refer to the following existing and future EPA materials:

LT2ESWTR Quick Reference Guides (Schedules 1 – 3) On-line Microscopy Training Module

On-line Sample Collection Module

Microbial Laboratory Guidance Manual for the Final Long Term 2 Enhanced Surface Water Treatment Rule (EPA 815-R06-006 February 2006)

Membrane Filtration Guidance Manual (EPA 815-R-06-009 November 2005)

Membrane Filtration Guidance Manual: Overview and Summary Factsheet (www.epa.gov/safewater/disinfection/lt2/pdfs/guide_lt2_membranefiltration_fs_final.pdf)

Ultraviolet Disinfection Guidance Manual and Workbook (final version anticipated mid-2006)

Simultaneous Compliance Guidance Manual for Stage 2 Rules (draft version anticipated mid-2006)

Long Term 2 Enhanced Surface Water Treatment Rule Toolbox Guidance Manual (draft version anticipated late 2006)

For additional information, please contact the Safe Drinking Water Hotline at 1-800-426-4791, send an email to stage2mdbp@epa.gov, or visit www.epa.gov/safewater/disinfection/lt2.

Office of Water (4606)                 EPA 816-F-06-017                  www.epa.gov/safewater/disinfection/lt2        June 2006

Microscopic Particulate Analysis ( MPA ) for Ground Water Under Direct Influence ( GWUDI ) Guide

 

Microscopic Particulate Analysis (MPA) For Evaluation of Ground Water

I.        What is “a ground water source under direct influence of surface water”?

 The EPA Guidance Manual defines a ground water source under direct influence of surface water as water in which there is either:

“significant occurrence of insects or macroorganisms, algae, organic debris, or large-diameter pathogens such as Giardia lamblia.”

or

“significant and relatively rapid shifts in water characteristics such  as turbidity, temperature, conductivity, or pH which closely correlate to climatological or surface water condition.”

 

II.     What information is useful in classification?

 

Historical water quality records

  1. At least three years of Total Coliform and/or Fecal Coliform
  2. Turbidity and temperature records including those of nearby surface water
  3. No history of a known or suspected outbreak of Giardia, Cryptosporidium or other pathogenic organisms associated with surface water that has been attributed to the
  4. No evidence of particulate matter associated with surface

 

On site inspection

  1. No evidence for surface water
  2. Sufficient distances from surface water

 

III.   What is MPA and how can it be used to differentiate ground water under surface influence?

 

The premise behind the use of microscopic particulate analysis (MPA) is that surface waters are subject to contamination by pathogens such as Giardia and that there are other organisms whose natural habitat is limited to surface waters. If these surface water organisms are found in ground water, then the water is subject to contamination with Giardia cysts and other pathogens.  Indicators of  surface water contamination of ground waters include: Giardia, coccidia including Cryptosporidium, diatoms and certain other algae, rotifers, green plant material, and insect parts.

 Cryptosporidium       

Cryptosporidium

Cymbella (Diatom)

Cymbella (Diatom)    

 Naviculla (Diatom) 

Naviculla (Diatom)

 

IV.   How is test conducted?

 Samples are collected in accordance with the EPA “Consensus Method for Determining Groundwaters Under the Direct Influence   of Surface Water Using Microscopic Particulate Analysis (MPA).” Two sampling events are recommended, one during a dry period and a second during a wet period. Turbidity, temperature, rainfall and stream flow records, and conductivity etc. may be used for guidance for when to test.

 

V.      How are results interpreted?

 When organisms such as Giardia , coccidian, such as Cryptosporidium, insect parts including nymphs, larvae and eggs, rotifers, diatoms and other algae are detected in groundwater, they  are useful as indicators of surface contamination. The process of scoring microscopic results with relative risk factors is beneficial in classifying questionable supplies.

 

Primary Indicators

Giardia – A protozoan parasite. Occurrence in water sample must be confirmed by identification of two or more morphological characteristics, nuclei, axoneme and/or median body.

Coccidia (Cryptosporidium and other coccidia) – Coccidia are protozoan parasites of vertebrates. Cryptosporidium, a pathogen of concern to human health is small in size (approximately 4-7 µm diameter). Cryptosporidium is very difficult to identify without IFA staining, and its occurrence is confirmed by identification of sporozoites within the oocyst.

Diatoms – Diatoms are prevalent in creeks and streams, and they require sunlight for photosynthesis and continued survival. It is important that the diatoms contain normal internal morphology including pigment in order to be significant for the purposes of this analysis.

Other Algae – Includes several groups of algae including the green and blue-green algae (Cyanobacteria). These algae are abundant in surface water and do not generally persist in the absence of sunlight.

Insects/Larvae – This category includes insects and their larvae and eggs. Insect parts are not as significant as intact organisms since insects molt and the external skeleton could persist in water for long periods of time.

Golenkinia (Green Alga) & Cyclotella (Diatom)   

Golenkinia (Green Alga) & Cyclotella (Diatom)

Coelastrum (Green Alga)

Coelastrum (Green Alga)

Tribonema (Golden Alga)   

Tribonema (Golden Alga)

Anabaena (Blue-Green Alga)  

Anabaena (Blue-Green Alga)

Insect Wing Scale

Insect Wing Scale

 

Rotifers – Organisms ranging in size 70-500 µm that are medium to good indicators of surface water influence, particularly when supported by the presence of other indicators.

Plant Debris – This category, in our opinion, is significant only when it relates to chlorophyll containing fragments of plant tissue, since the plant debris could persist in water for extended periods of time much beyond the viability of Giardia or other pathogen cysts.

 

Secondary Indicators

Nematodes – Nematodes and or their eggs are common in surface water and in ground waters with detritus and organic debris.

Crustaceans – Many species occur in surface waters.

Amoebae – Free living amoebae. Large numbers of amoebae in groundwater may indicate substantial bacterial populations or organic detritus in the water.

Non-photosynthetic flagellates and ciliates – Free-living protozoa are extremely common in healthy surface sources. Like amoebae, they feed on bacteria, algae, small metazoans, other protozoa and extraneous debris. Although many flagellates are photosynthetic, there are a number of species that grow in the absence of light providing sufficient dissolved nutrients are available.

Photosynthetic flagellates – Includes species such as Euglena. While these organisms are photosynthetic, many can persist in the dark for months and because they are motile, their presence may not be indicative of surface water contamination.

Other: Other organisms frequently seen in MPA samples include the iron bacteria. The presence of iron bacteria does not have significance for surface infiltration, but large numbers of iron bacteria can produce biofouling of the well.

The EPA risk factor tables are used to weight the results of MPA analyses. The greatest weight is given to the primary indicators.

 

Table 1 assigns a rating (Not Significant through Extremely Heavy).

 

Table 2 uses the ratings assigned by Table 1 to determine the Relative  Risk Factor.

Table 1: Numerical range of each primary bio-indicator (particulate) counted per 100 gallons water.

Indicators of surface water1 EH3 H M R NS
Giardia2 >30 16 to 30 6 to 15 1 to 5 <1
Coccidia2 >30 16 to 30 6 to 15 1 to 5 <1
Diatoms4 >150 41 to 149 11 to 40 1 to 10 <1
Other Algae4 >300 96 to 299 21 to 95 1 to 20 <1
Insects/Larvae >100 31 to 99 16 to 30 1 to 15 <1
Rotifers >150 61 to 149 21 to 60 1 to 20 <1
Plant Debris4 >200 71 to 200 26 to 70 1 to 25 <1

 

  1. According to EPA “Guidance Manual for Compliance with the Filtration and Disinfection Requirements for Public Water Systems Using Surface Water Sources”, March, 1991
  2. If Giardia cysts or coccidian are found in any sample, irrespective of volume, score as
  3. Key: EH-Extremely High, H-Heavy, M-Moderate, R-Rare, NS-Not Significant
  4. Chlorophyll Containing

 

Table 2: Relative surface water risk factors associated with scoring or primary bio-indicators (particulate) present during MPA of subsurface water sources.

Indicators of surface water1 Relative Risk Factor3
EH2 H M R NS
Giardia 40 30 25 20 0
Coccidia 35 30 25 20 0
Diatoms 16 13 11 6 0
Other Algae 14 12 9 4 0
Insects/Larvae 9 7 5 3 0
Rotifers 4 3 2 1 0
Plant Debris 3 2 1 0 0

 

  1. According to EPA “Guidance Manual for Compliance with the Filtration and Disinfection Requirements for Public Water Systems Using Surface Water Sources”, March, 1991
  2. Key: EH – Extremely High, H – Heavy, M – Moderate, R – Rare, NS – Not Significant
  3. Risk of surface water contamination:

>20 – High risk, 10-19 – Moderate risk, <9 – Low Risk

 

*Note: Any finding of Giardia or Cryptosporidium results in a minimum risk factor of 20.

 

*Appendix 1. Tables 1 & 2 from Vasconcelos, J. 1992 Consensus Method for Determining Groundwaters Under the Direct Influence of Surface Water Using Microscopic Particulates Analysis (MPA). U.S. Environmental Protection Agency, Region 10 Oct. p. 30-31.

Cryptosporidium Unpressurized Sample Filtration Envirochek™ HV Capsules

1. Install filter capsule and turn on pump
2, Record start time and initial meter reading
3. Bleed out air and adjust flow rate up to a maximum of 2 L/min
4. When at least 10 L has passed through the filter, turn off pump
5. Record stop time and final meter reading
6. Hold inlet pointing up, remove outlet tubing and allow water to drain
7. Open bleed valve to speed the draining process and disconnect inlet tubing
8. Seal the capsule with vinyl end caps, close the bleed valve, and place in gallon-size zippered plastic bag
9, Chill the sample as soon as possible to between 1° and 10°C
until ready for shipment

Cryptosporidium Pressurized Sample Filtration Envirochek™ HV Capsules

1. Install filter capsule
2, Record start time and initial meter reading
3. Slowly open sample tap, bleed out air, and adjust up to the following maximum values:
• 100 psig and 2 L/min
4. When at least 10 L has passed through the filter, turn off sample tap allowing pressure to decrease until water stops
5. Record stop time and final meter reading
6. Hold inlet pointing up, remove outlet tubing and allow water to drain
7. Open bleed valve to speed the draining process and disconnect inlet tubing
8. Seal the capsule with vinyl end caps, close the bleed valve, and place in gallon-size zippered plastic bag
9, Chill the sample as soon as possible to between 1° and 10°C until ready for shipment

 

Cryptosporidium Preparation for Sample Filtration

Thoroughly clean* all reused collection equipment and containers (new tubing,
fittings, etc. should not need cleaning), and wear gloves whenever needed to
prevent sample contamination throughout the collection and filtration procedure.
Before connecting the sampling unit to the tap, thoroughly flush stagnant water
and debris in the sample line until the temperature and turbidity stabilize
(approx. 2-3 mins).

Complete the sample collection form including utility and
sample ID information, date, turbidity, pH and temperature.

Pressurized source

1. Determine sample line water pressure at the location described to the State
2. Connect assembled sampling unit, without capsule/foam filter, to sample tap
3. Flush the sampling unit for 2-3 minutes and test for leaks

Unpressurized source

1. Fill 30+ L carboy from a pressurized sample tap or manually collect the sample
using hose, pump, funnel, etc. from the location described to the State
2. Chill the full carboy to between 1° and 10°C if filtration is not performed
immediately after filling the carboy
3. Assemble sampling unit, without capsule/foam filter, and insert influent tube
into the center of the carboy
4. Turn on pump to flush the sampling unit for 2-3 minutes and test for leaks
* Refer to the cleaning procedure located on the Packing and Shipping panel
of this pocket guide

E. coli Sample Collection

Wear gloves whenever needed to prevent sample contamination throughout the collection procedure.

Complete the sample collection form including utility and sample ID information, date and time, etc.

1. Water taps used for sampling should be free of aerators, hose attachments, etc.
2. Prior to sample collection, thoroughly flush stagnant water and debris in the sample line until the temperature and turbidity stabilize (approx, 2-3 mins):
DO NOT rinse the sample bottle
3. Record the turbidity, pH, and temperature
4. Aseptically fill the sterile E. coli sample bottle from a pressurized sample tap or manually collect sample using,hose, pump, funnel, etc, from the location described to the State
5. Leave at least one inch of head space in the E. coli sample bottle, if possible. Collect at least 100 ml of sample for analysis
6. Immediately close the sample bottle
7. Chill sample as soon as possible to between 0″ and 10’C until ready for immediate shipment

Cryptosporidium Matrix Spike Sample Collection

Send an extra 10 L bulk sample for spiking at the Cryptosporidium laboratory
concurrent with the 1st and 21st routine monitoring sample collections and
again with every 20 samples if more than 40 source water samples are
collected. Coordinate the collection of matrix spike samples with your laboratory.
Matrix spike samples should be collected from the same location and at the
same time as the associated routine sample. The matrix spike sample and
routine sample should be the same volume. Label the cubitainer with the
following information using a waterproof pen: PWSID, facility name, and sample
collection date. Chill the sample as soon as possible to between 1° and 10°C
before shipment.

10-L Matrix Spike Sample

Follow instructions for collecting a
10-L bulk water sample given on
previous panel.

Matrix Spike Samples Greater than 10-L

Either ship the entire matrix spike volume
as a bulk sample to the laboratory to be spiked and analyzed, OR filter all
but 10 L of the matrix spike sample at your utility and collect the remaining
10 L as a bulk sample. Chill both the filter and bulk sample as soon as possible
to between 1° and 10°C before shipment. Clearly label both the filter and
bulk sample as comprising 2 parts of a single sample.

EPA LT2 Cryptosporidium & Giardia 10 liter Bulk Water Collection

Cryptosporidium

10-L   Bulk Water Collection

Thoroughly clean* all reused collection equipment and containers (new hoses, cubitainers, etc. should not need cleaning), and wear gloves whenever needed to prevent sample contamination throughout the collection procedure. Prior to sample collection, thoroughly flush stagnant water and debris in the sample line until the temperature and turbidity stabilize (approx. 2-3 mins).

Complete the sample collection form including utility and sample ID information, date, time, turbidity, pH, and temperature.
  1. Fill the 10-L cubitainer from a pressurized sample tap or manually collect sample using hose, pump, funnel, etc. from the location described to the State.
  1. Once the sample is collected, immediately place the cap on the cubitainer and tighten
  2. Chill the sample as soon as possible to between 1° and 10°C before shipment