Md. Code Regs. 15.18.04.05

Current through Register Vol. 51, No. 26, December 27, 2024
Section 15.18.04.05 - Compost Classification
A. A compost product is classified as a General Use, Limited Use, or Restricted Use compost as shown in §§B-D of this regulation.
B. General Use Compost.
(1) General Use compost may not exceed the following specifications:

ParameterParameter LimitAll limits apply toproduct leavingcomposting facility.
(a) pH (range)6.0-8.0
(b) Heavy metals (maximum)
(i) Arsenic41 mg/kg dry wt.
(ii) Cadmium39 mg/kg dry wt.
(iii) Chromium1200 mg/kg dry wt.
(iv) Copper1500 mg/kg dry wt.
(v) Lead300 mg/kg dry wt.
(vi) Mercury17 mg/kg dry wt.
(vii) Molybdenum18 mg/kg dry wt.
(viii) Nickel420 mg/kg dry wt.
(ix) Selenium36 mg/kg dry wt.
(x) Zinc2800 mg/kg dry wt.
(c) PCBs5 ppm
(d) Man-made inerts (maximum)>4mm, <13mm2 percent dry wt.
(e) Film plastic >4mm2 percent dry wt.
(f) Process to further reducepathogens (required for compost from municipalsolid waste or manure)pass

(2) A General Use compost:
(a) Shall pass through a 12mm (1/2 inch) screen;
(b) Shall be stabilized;
(c) May not have an objectionable odor; and
(d) May be distributed as a soil conditioner for use by the general public or for any use allowed by this chapter.
C. Limited Use Compost.
(1) A Limited Use compost may not exceed the following specifications:

ParameterParameter LimitAll limits apply toproduct leavingcomposting facility.
(a) pH (range)6.0-8.0
(b) Heavy metals (maximum)
(i) Arsenic41 mg/kg dry wt.
(ii) Cadmium39 mg/kg dry wt.
(iii) Chromium1200 mg/kg dry wt.
(iv) Copper1500 mg/kg dry wt.
(v) Lead300 mg/kg dry wt.
(vi) Mercury17 mg/kg dry wt.
(vii) Molybdenum18 mg/kg dry wt.
(viii) Nickel420 mg/kg dry wt.
(ix) Selenium36 mg/kg dry wt.
(x) Zinc2800 mg/kg dry wt.
(c) PCBs10 ppm
(d) Man-made inerts (maximum)>4mm4 percent dry wt.
(e) Film plastic >4mm2 percent dry wt.
(f) Process to further reducepathogens (required for compost from municipalsolid waste or manure)pass

(2) A Limited Use compost:
(a) Shall pass through an 18mm (3/4 inch) screen;
(b) Shall be stabilized;
(c) May not have an objectionable odor; and
(d) May only be distributed for use by a commercial, agricultural, institutional, or governmental operation, or for restricted use as provided by this chapter.
D. Restricted Use Compost:
(1) A Restricted Use compost may not exceed the indicated maximum level for any heavy metal or trace element, as follows:

(a) Arsenic75 mg/kg dry wt.
(b) Cadmium85 mg/kg dry wt.
(c) Chromium3000 mg/kg dry wt.
(d) Copper4300 mg/kg dry wt.
(e) Lead840 mg/kg dry wt.
(f) Mercury57 mg/kg dry wt.
(g) Molybdenum75 mg/kg dry wt.
(h) Nickel420 mg/kg dry wt.
(i) Selenium100 mg/kg dry wt.
(j) Zinc7500 mg/kg dry wt.

(2) A Restricted Use compost:
(a) May not be a hazardous waste, as defined in COMAR 26.13.02.03D;
(b) May not be stockpiled or disposed of unless authorized by the Maryland Department of the Environment;
(c) May not be distributed or sold to the general public;
(d) Is restricted to distribution for use as a final, intermediate, or alternate daily landfill cover, as provided by COMAR 26.04.07, or on marginal land or in land reclamation efforts if applied at rates not to exceed limits established in Table 2 of Regulation .12 of this chapter; and
(e) Includes any compost exceeding any parameter limit for Limited Use compost, as provided in Regulation .05C of this chapter, or any compost designated by the registrant as Restricted Use classification.

Md. Code Regs. 15.18.04.05