Cryptosporidium Monitoring for Compliance with the LT2 Rule

1
Cryptosporidium Monitoring for Compliance with
the LT2 Rule
Tim Stefanich - Environmental Engineer Sioux
Falls Water Purification
2
What do I need to do to prepare?

• Are you required to sample?
• All SW and GWUDI systems must sample

System Size and Type Monitor For Frequency Duration
Filtered Systems gt 10,000 Cryptosporidium E. Coli Turbidity 1 per month 24 months
Filtered Systems lt 10,000 E. Coli 2 per month 24 months
Cryptosporidium 1 per month 2 per month 24 months 12 months
E. coli results may trigger Cryptosporidium
monitoring. If annual mean E. coli gt 10 / 100
ml when using lake / reservoir then must sample
for crypto. If annual mean E. coli gt 50 / 100 ml
when using flowing stream, then must sample for
crypto. (SWM GM table 1-1)
3
What do I need to do to prepare?

• When do I begin to sample?

System that serve. Must begin the first round of sampling no later than the end of
At least 100,000 people October 2006
From 50,000 to 99,999 people April 2007
From 10,000 to 49,999 people April 2008
Fewer than 10,000 and monitor for E. Coli October 2008
Fewer than 10,000 and monitor for Crypto April 2010
4
What do I need to do to prepare?

• Obtain a copy of the rule (153 pages)
• Obtain EPA Guidance Manuals
• Surface Water Monitoring GM (151 pages)
• Microbial Laboratory GM (273 pages)
• Obtain list of EPA approved labs
• EPA Crypto and e-coli sampling pocket guide
• State Point of Contact Mark Mayer
• http//www.epa.gov/ogwdw/disinfection/lt2/
  index.html

5
Guidance Manuals

• Surface Water Monitoring GM
• Setting up contract for lab services
• Sampling location and schedule
• Collecting and shipping
• Grandfathering
• Reviewing and submitting data
• Microbial Laboratory GM
• Laboratory analysis methods
• How to receive laboratory approval

6
Research Cryptosporidium Sampling / Testing
Methods

• Method 1622 Cryptosporidium in water
• Method 1623 Cryptosporidium and Giardia in
  water
• LT2 Rule does not require monitoring for or
  reporting of results for analysis of Giardia.
• Little additional cost for Giardia analysis
• Sampling requirements are identical between
  methods
• Must use an EPA approved laboratory

7
Research Sampling Procedures

• Collect and ship bulk water samples
• Sample size (10 50 liter)
• Shipping costs
• Extra cost for lab to filter sample
• Filter sample on-site and ship filter.
• Purchase own equipment?
• Rent equipment?
• Type of filter used?
• Suggest spare equipment and filters

8
Filter Sample On-Site

• Two types of filters approved
• IDEXX Filta-Max
• Less expensive
• Separate filter and holder
• Tolerant to higher pressures (lt 120 psi)
• Flow rate 3 4 L/min

9
Filter Sample On-Site

• Envirochek or Envirochek HV
• More expensive (2X)
• Integrated filter and holder
• Less tolerant to higher pressure
• 30 psi for Envirochek
• 60 psi for Envirochek HV
• Higher flow rate for HV
• 2 L/min for Envirochek
• 4 L/min for Envirochek HV
• Some labs may be specific as to the type of
  filter used.

10
Sample Size

• Minimum 10 Liter sample
• Highly turbid samples may require more than 1
  filter to get minimum 10 liters.
• Recommend that sample size be consistent through
  the sampling period

11
Sampling Frequency

• Matrix spikes
• Required at least every 20 field samples
• Used by lab to spike with Crypto, filter, and
  analyze to determine recovery within your source
  water.
• Allowed to pre-filter any sample over 10 liters
  and shipping filter and remaining 10 liters for
  spiking
• Sample taken same time or right before or after
  as regular crypto sample.

12
Sample Collection Location

• Source water prior to any chemical addition,
  treatment, or addition of backwash water
• Multiple sources may require volume weighted
  samples
• Ex. Source A 25
• Source B 75
• Volume Weighted Sample (one 10L Sample)
• Volume A 2.5 L
• Volume B 7.5 L
• Yields 1 result and you pay for one sample
• Result weighted sample (pay for 2 analysis)

13
Sampling Schedule

• Laboratory schedule will dictate your sampling
  schedule
• The sooner you select a lab and start sampling,
  the better date selection you will have
• Sampling schedule must be consistent from month
  to month. (Ex - 17th of each month)
• Sample must be collected within 2 days of date
  selected (Ex 15th to 19th)

14
Shipping

• Overnight
• Will shipper accept coolers?
• Do they charge extra for handling coolers?
• Do not allow contents to freeze
• Insulation between blue
• ice and filters or bulk sample
• Max temp lt 20 C
• Do not forget the
• paperwork
• Datasheets
• Chain of custody record

15
Results

• Turnaround time
• 10 to 15 days but check with lab
• Shorter TAT can lead to higher costs

16
Sampling Equipment Selection

• 15 Liter Poly Carboy (2)
• ½ 5/8 dia. reinforced vinyl hoses
• Garden hose type quick disconnects

17
Sampling Equipment Selection

• SHURflo diaphragm pump
• 1.7 gpm
• 95 psi max

• Filta-Max filter holder or
• Envirochek filter

18
Sampling Equipment Selection

• Badger flow meter
• Gallons
• Totalizer

• Flow control valve

19
Raw Water Sampling Sites

• 2 separate sources
• Surface water
• Chemical added and treated prior to mixing with
  groundwater
• Groundwater

Groundwater
Actiflo
Big Sioux River
Backwash Water
Potassium Permanganate
20
Sampler Setup
21
Data Collection Sheet
22
Finished Water Sampling
23
Results (To be Grandfathered)

• 50 samples since Jan 20, 2004
• Average volume collected 10.5 L
• No detections (Detect limit Avg 9.78 / 100 L)
• E. Coli range lt 1 to 200 colonies / 100 ml
• Turbidity range 2.4 - 24 NTU
• 3 Matrix spike samples
• Crypto recovery range 38.4 58
• Giardia recovery range 43.4 68.7

24
Summary of all Results

• Big Sioux River (1994 to present)
• Only sample when on-line
• Cryptosporidium
• 2 detections
• Range from 17.2 100 cysts per 100 L
• Last detection Jan 2004
• Giardia
• 6 detections
• Range from 4.9 83 cysts / 100 L
• Last detection Dec 2002

25
Summary of All Results

• Raw Water (1994 Present)
• Cryptosporidium
• 4 detections
• Range from 1 89 cysts per 100 L
• Last detection May, 1996
• Giardia
• 9 detections
• Range from 9 333 cysts / 100 L
• Last detection Oct 2000
• Finished Water (1994 Present)
• No detections
• Average detection limit of 1.2 / 100 Liters