35 Ill. Adm. Code 391.501
Sludge Sampling and Analysis
Section 391
Section 391.501 Sludge
Sampling and Analysis
a) Permit applications, except water treatment plant sludge
application projects, shall provide analyses for the following parameters;
1) % total solids, % volatile solids, pH, volatile acids (if
anaerobic digestion is used);
2) Total Kjeldahl nitrogen, ammonia nitrogen, phosphorus and
potassium;
3) Cadmium, copper, lead, manganese, nickel and zinc.
b) All analyses for Subsections (a)(2) and (3) above must be
reported in mg/kg (dry weight basis).
c) Wastewater treatment plants whose design population
equivalents are less than 1000, which have sanitary sewers not subject to large
inflow sources and do not receive any industrial process wastewater may request
an exemption from analyzing the metals under Subsection 391.501 (a) (3) except
for cadmium which must always be analyzed. These generators shall periodically
analyze their sludge used for land application and make the necessary
calculations for nutrient and heavy metal loadings in accordance with the
following schedule:
Design Population Equivalents
Frequency of Sludge Analysis
>100,000
Monthly
10,000-100,000
Quarterly
1000-9999
Semi-annual
<1000
Annual
1) If a treatment plant sludge application project is limited by
heavy metal loading more frequent sludge analysis shall be required by the
Agency as necessary to assure compliance with the Act and 35 Ill. Adm. Code,
Subtitle C, Subchapter l.
2) If sludge analyses show only minor deviations in sludge
quality, the applicant may request a less frequent sludge sampling and analysis
program or compositing of samples with less frequent analyses of samples.
d) Water treatment plant sludge permit applications shall provide
analyses for the following parameters:
1) % total solids, pH, % calcium carbonate equivalent;
2) Arsenic, barium, cadmium, chromium (hexavalent), chromium
(total), copper, mercury, nickel, selenium, silver and zinc;
3) The Agency shall request an applicant to analyze water
treatment plant sludge for additional parameters and limit sludge application
rates based on these other parameters as necessary to prevent groundwater or
surface water pollution, phytotoxicity, mammalian toxicity or other
environmental concerns.
4) If raw water or sludge analyses show only negligible amounts
of metals listed in (d)(2) above, the applicant may request less parameters to
be analyzed.
e) All analyses for Subsection (d)(2) above must be reported in
mg/kg (dry weight basis).
f) Water treatment plants shall analyze their sludge on an annual
basis. For facilities that have on-site storage lagoons, analyses shall be
performed at the time of lagoon cleanout.