007.01
Cryptosporidium
Systems must analyze for Cryptosporidium
using Method 1623: Cryptosporidium and
Giardia in Water by Filtration/IMS/FA, 2005, United States
Environmental Protection Agency, EPA-815-R- 05-002 or Method 1622:
Cryptosporidium in Water by Filtration/IMS/FA, 2005, United States
Environmental Protection Agency, EPA-815-R- 05-001, which are incorporated by
reference or an equivalent method approved by EPA. A copy of these methods may
be obtained online from
http://www.epa.gov/safewater/disinfection/lt2 or from
the United States Environmental Protection Agency, Office of Ground Water and
Drinking Water, 1201 Constitution Ave., NW, Washington, DC 20460 (Telephone:
800-426-4791). A copy may be inspected at the office of the Division of Public
Health of the Department of Health and Human Services, 301 Centennial Mall
South, Lincoln, NE 68509.
25-007.01A
Systems must analyze at least a 10 liter (L) sample or a packed pellet volume
of at least 2 milliliter (mL) as generated by the methods listed in 179 NAC
25-007.01. Systems unable to process a 10 L sample must analyze as much sample
volume as can be filtered by two filters approved by EPA for the methods listed
in 179 NAC 25-007.01, up to a packed pellet volume of at least 2 mL.
25-007.01B
Procedure for Matrix
Spike Samples
25-007.01B1 Matrix
Spike (MS) samples, as required by the methods in 179 NAC 25-007.01, must be
spiked and filtered by a laboratory approved for Cryptosporidium
analysis under 179 NAC
25-008.
25-007.01B2 If the volume of the MS sample is
greater than 10 L, the system may filter all but 10 L of the MS sample in the
field, and ship the filtered sample and the remaining 10 L of source water to
the laboratory. In this case, the laboratory must spike the remaining 10 L of
water and filter it through the filter used to collect the balance of the
sample in the field.
25-007.01C Flow cytometer-counted spiking
suspensions must be used for MS samples and ongoing precision and recovery
(OPR) samples.
007.02 E.
coli
Systems must use methods for enumeration of E. coli
in source water approved in
40 CFR
136.3(a) or equivalent
methods approved by EPA. Available from American Public Health Association, 800
I Street, NW, Washington, DC 20001-3710.
25-007.02A The time from sample collection to
initiation of analysis may not exceed 30 hours unless the system meets the
condition of 179 NAC
25-007.02B.
25-007.02B The Department may approve on a
case-by-case basis the holding of an E. coli sample for up to
48 hours between sample collection and initiation of analysis if the Department
determines that analyzing an E. coli sample within 30 hours is
not feasible. E. coli samples held between 30 to 48 hours must
be analyzed by the Colilert reagent version of Standard Method 9223B as listed
in
40 CFR
136.3(a).
25-007.02C Systems must maintain samples
between 0º C and 10º C during storage and transit to the
laboratory.
007.03
Turbidity
Systems must use methods for turbidity measurement approved
in 179 NAC
13-007.01A.
