Wyoming Administrative Code
Agency 020 - Environmental Quality, Dept. of
Sub-Agency 0011 - Water Quality
Chapter 15 - USE OF SURFACE DISPOSAL OF BIOSOLIDS, APP. A-C
Part C - SURFACE DISPOSAL
Section 31 - Pathogens
Universal Citation: WY Code of Rules 31
Current through September 21, 2024
(a) Biosolids - Class A.
(i) The requirement in Section 31(a) (ii) and
the requirements in either Section 31(a) (iii), (a) (iv), (a) (v), (a) (vi),
(a) (vii), or (a) (viii)shall be met for a biosolids to be classified Class A
with respect to pathogens.
(ii) The
Class A pathogen requirements in Section 31(a) (iii) through (viii) shall be
met either prior to meeting or at the same time the vector attraction reduction
requirements in Section 32, except the vector attraction reduction requirements
in Section 32(k) through (m), are met.
(iii) Class A - Alternative 1.
(A) Either the density of fecal coliform in
the biosolids shall be less than 1000 Most Probable Number per gram of total
solids (dry weight basis), or the density of
Salmonella sp. bacteria in the biosolids shall be less
than three Most Probable Number per four grams of total solids (dry weight
basis) at the time the biosolids is used or disposed; at the time the biosolids
is prepared for sale or give away in a bag or other container for application
to the land; or at the time the biosolids or material derived from biosolids is
prepared to meet the requirements in Section 11(b) through (e), (g) or
(h).
(B) The temperature of the
biosolids that are used or disposed shall be maintained at a specific value for
a period of time.
(I) When the percent solids
of the biosolids is seven percent (7%) or higher, the temperature of the
biosolids shall be 50 degrees Celsius or higher; the time period shall be 20
minutes or longer; and the temperature and time period shall be determined
using equation (2), except when small particles of biosolids are heated by
either warmed gases or an immiscible liquid.
D = 131,700,000 Eq.(2)
100.1400t
Where,
D = time in days.
t = temperature in degrees Celsius.
(II) When the percent solids of the biosolids
is seven percent (7%) or higher and small particles of biosolids are heated by
either warmed gases or an immiscible liquid, the temperature of the biosolids
shall be 50 degrees Celsius or higher; the time period shall be 15 seconds or
longer; and the temperature and time period shall be determined using equation
(2).
(III) When the percent solids
of the biosolids is less than seven percent (7%) and the time period is at
least 15 seconds, but less than 30 minutes, the temperature and time period
shall be determined using equation (2).
(IV) When the percent solids of the biosolids
is less than seven percent (7%); the temperature of the biosolids is 50 degrees
Celsius or higher; and the time period is 30 minutes or longer, the temperature
and time period shall be determined using equation (3).
D = 50,070,000/100.1400t Eq.(3)
Where,
D = time in days.
t = temperature in degrees Celsius.
(iv) Class A
- Alternative 2.
(A) Either the density of
fecal coliform in the biosolids shall be less than 1000 Most Probable Number
per gram of total solids (dry weight basis), or the density of
Salmonella sp. bacteria in the biosolids shall be less
than three Most Probable Number per four grams of total solids (dry weight
basis) at the time the biosolids is used or disposed; at the time the biosolids
is prepared for sale or give away in a bag or other container for application
to the land; or at the time the biosolids or material derived from biosolids is
prepared to meet the requirements in Section 11(b) through (e), (g) or
(h).
(B) The pH of the biosolids
that is used or disposed shall be raised to above 12 and shall remain above 12
for 72 hours.
(C) The temperature
of the biosolids shall be above 52 degrees Celsius for 12 hours or longer
during the period that the pH of the biosolids is above 12.
(D) At the end of the 72 hour period during
which the pH of the biosolids is above 12, the biosolids shall be air dried to
achieve a percent solids in the biosolids greater than 50 %.
(v) Class A - Alternative 3.
(A) Either the density of fecal coliform in
the biosolids shall be less than 1000 Most Probable Number per gram of total
solids (dry weight basis), or the density of
Salmonella sp. bacteria in biosolids shall be less
than three Most Probable Number per four grams of total solids (dry weight
basis) at the time the biosolids is used or disposed; at the time the biosolids
is prepared for sale or give away in a bag or other container for application
to the land; or at the time the biosolids or material derived from biosolids is
prepared to meet the requirements in Section 11(b) through (e), (g) or
(h).
(B) The biosolids shall be
analyzed prior to pathogen treatment to determine whether the biosolids contain
enteric viruses.
(C) When the
density of enteric viruses in the biosolids prior to pathogen treatment is less
than one Plaque-forming Unit per four grams of total solids (dry weight basis),
the biosolids is Class A with respect to enteric viruses until the next
monitoring episode for the biosolids.
(D) When the density of enteric viruses in
the biosolids prior to pathogen treatment is equal to or greater than one
Plaque-forming Unit per four grams of total solids (dry weight basis), the
biosolids are Class A with respect to enteric viruses when the density of
enteric viruses in the biosolids after pathogen treatment is less than one
Plaque-forming Unit per four grams of total solids (dry weight basis) and when
the values or ranges of values for the operating parameters for the pathogen
treatment process that produces the biosolids that meets the enteric virus
density requirement are documented.
(E) After the enteric virus reduction in (a)
(v) (D) of this subsection is demonstrated for the pathogen treatment process,
the biosolids continues to be Class A with respect to enteric viruses when the
values for the pathogen treatment process operating parameters are consistent
with the values or ranges of values documented in (a) (v) (D) of this
subsection.
(F) The biosolids shall
be analyzed prior to pathogen treatment to determine whether the biosolids
contains viable helminth ova.
(G)
When the density of viable helminth ova in the biosolids prior to pathogen
treatment is less than one per four grams of total solids (dry weight basis),
the biosolids is Class A with respect to viable helminth ova until the next
monitoring episode for the biosolids.
(H) When the density of viable helminth ova
in the biosolids prior to pathogen treatment is equal to or greater than one
per four grams of total solids (dry weight basis), the biosolids is Class A
with respect to viable helminth ova when the density of viable helminth ova in
the biosolids after pathogen treatment is less than one per four grams of total
solids (dry weight basis) and when the values or ranges of values for the
operating parameters for the pathogen treatment process that produces the
biosolids that meets the viable helminth ova density requirement are
documented.
(I) After the viable
helminth ova reduction in (a) (v) (C) of this subsection is demonstrated for
the pathogen treatment process, the biosolids continues to be Class A with
respect to viable helminth ova when the values for the pathogen treatment
process operating parameters are consistent with the values or ranges of values
documented in (a) (v) (C) of this subsection.
(vi) Class A - Alternative 4.
(A) Either the density of fecal coliform in
the biosolids shall be less than 1000 Most Probable Number per gram of total
solids (dry weight basis), or the density of
Salmonella sp. bacteria in the biosolids shall be less
than three Most Probable Number per four grams of total solids (dry weight
basis) at the time the biosolids is used or disposed; at the time the biosolids
is prepared for sale or give away in a bag or other container for application
to the land; or at the time the biosolids or material derived from biosolids is
prepared to meet the requirements in Section 11(b) through (e), (g) or
(h).
(B) The density of enteric
viruses in the biosolids shall be less than one Plaque-forming Unit per four
grams of total solids (dry weight basis) at the time the biosolids is used or
disposed; at the time the biosolids is prepared for sale or give away in a bag
or other container for application to the land; or at the time the biosolids or
material derived from biosolids is prepared to meet the requirements in Section
11(b) through (e), (g) or (h), unless otherwise specified by the permitting
authority.
(C) The density of
viable helminth ova in the biosolids shall be less than one per four grams of
total solids (dry weight basis) at the time the biosolids is used or disposed;
at the time the biosolids is prepared for sale or give away in a bag or other
container for application to the land; or at the time the biosolids or material
derived from biosolids is prepared to meet the requirements in Section 11(b)
through (e), (g) or (h), unless otherwise specified by the permitting
authority.
(vii) Class A
- Alternative 5.
(A) Either the density of
fecal coliform in the biosolids shall be less than 1000 Most Probable Number
per gram of total solids (dry weight basis), or the density of
Salmonella, sp. bacteria in the biosolids shall be
less than three Most Probable Number per four grams of total solids (dry weight
basis) at the time the biosolids is used or disposed; at the time the biosolids
is prepared for sale or give away in a bag or other container for application
to the land; or at the time the biosolids or material derived from biosolids is
prepared to meet the requirements in Section 11(b) through (e), (g) or
(h).
(B) Biosolids that are used or
disposed shall be treated in one of the Processes to Further Reduce Pathogens
described in Appendix B.
(viii) Class A - Alternative 6.
(A) Either the density of fecal coliform in
the biosolids shall be less than 1000 Most Probable Number per gram of total
solids (dry weight basis), or the density of
Salmonella, sp. bacteria in the biosolids shall be
less than three Most Probable Number per four grams of total solids (dry weight
basis) at the time the biosolids is used or disposed; at the time the biosolids
is prepared for sale or give away in a bag or other container for application
to the land; or at the time the biosolids or material derived from biosolids is
prepared to meet the requirements in Section 11(b) through (e), (g) or
(h).
(B) Biosolids that are used or
disposed shall be treated in a process that is equivalent to a Process to
Further Reduce Pathogens, see Appendix B, as determined by the permitting
authority.
(b) Biosolids - Class B.
(i) The requirements in one of the following
will be met, Section 31(b) (iii), (b) (iv), or (b) (v), for biosolids to be
classified Class B with respect to pathogens.
(ii) The site restrictions in Section 31(b)
(vi) shall be met when biosolids that meets the Class B pathogen requirements
in Section 31(b) (iii), (b) (iv), or (b) (v) is applied to the land.
(iii) Class B - Alternative 1.
(A) Seven samples of the biosolids shall be
collected at the time the biosolids are used or disposed.
(B) The geometric mean of the density of
fecal coliform in the samples collected in (b) (iii) (A) of this subsection
shall be less than either 2,000,000 Most Probable Number per gram of total
solids (dry weight basis) or 2,000,000 Colony Forming Units per gram of total
solids (dry weight basis).
(iv) Class B - Alternative 2. Biosolids that
are used or disposed shall be treated in one of the Processes to Significantly
Reduce Pathogens described in Appendix B.
(v) Class B - Alternative 3. Biosolids that
are used or disposed shall be treated in a process that is equivalent to a
Process to Significantly Reduce Pathogens, as determined by the permitting
authority.
(vi) Site Restrictions.
(A) Food crops with harvested parts that
touch the biosolids/soil mixture and are totally above the land surface shall
not be harvested for 14 months after application of biosolids.
(B) Food crops with harvested parts below the
surface of the land shall not be harvested for 20 months after application of
biosolids when the biosolids remains on the land surface for four months or
longer prior to incorporation into the soil.
(C) Food crops with harvested parts below the
surface of the land shall not be harvested for 38 months after application of
biosolids when the biosolids remains on the land surface for less than four
months prior to incorporation into the soil.
(D) Food crops, feed crops, and fiber crops
shall not be harvested for 30 days after application of biosolids.
(E) Animals shall not be allowed to graze on
the land for 30 days after application of biosolids.
(F) Turf grown on land where biosolids are
applied shall not be harvested for one year after application of the biosolids
when the harvested turf is placed on either land with a high potential for
public exposure or a lawn, unless otherwise specified by the permitting
authority.
(G) Public access to
land with a high potential for public exposure shall be restricted for one year
after application of biosolids.
(H)
Public access to land with a low potential for public exposure shall be
restricted for 30 days after application of biosolids.
(c) Domestic septage.
(i) The site restrictions in Section 31(b)
(vi) shall be met when domestic septage is applied to agricultural land,
forest, or a reclamation site; or
(ii) The pH of domestic septage applied to
agricultural land, forest, or a reclamation site shall be raised to 12 or
higher by alkali addition and, without the addition of more alkali, shall
remain at 12 or higher for 30 minutes and the site restrictions in Section
31(b) (vi) (A) through (b) (vi) (D) shall be met.
(iii) The requirements of this section are
satisfied by compliance with the conditions in a General Statewide Permit for
Land Application of Domestic Sewage In Remote Areas, see Appendix C.
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