5 Colo. Code Regs. § 1002-64.15

Current through Register Vol. 47, No. 11, June 10, 2024

Section 5 CCR 1002-64.15 - USE OF BIOSOLIDS FOR AGRICULTURE AND RECLAMATION

A.Land Application of Biosolids.

(1) No person shall use biosolids, distribute biosolids for use, or cause biosolids to be used for any beneficial use unless a Notice of Authorization for the Use and Distribution of Biosolids has been issued by the Division pursuant to section 64.10 of these regulations for such use or distribution.

(2) No person shall apply biosolids to land unless:

(a) the biosolids meet at a minimum the Table 1 Ceiling Concentration Limits with respect to metals as defined in section 64.12(A), of this regulation, and

(b) the biosolids either:

(i) meet the criteria for Class A with respect to pathogen destruction as defined in section 64.12 of these regulations, and meet at least one of the vector attraction reduction criteria as defined in paragraphs 64.12(C)(3) through (13) of these regulations when the biosolids are applied to a public contact site, or

(ii) the biosolids meet the criteria for Class B with respect to pathogen destruction as defined in section 64.12 of these regulations, and meet at least one of the vector attraction reduction criteria as defined in paragraphs 64.12(C)(3) through (13) of these regulations when the biosolids are applied to land for agricultural use or to disturbed land for reclamation, and

(3) No person shall land apply biosolids for any beneficial use if such application is likely to adversely affect a threatened or endangered species listed under section 64.4 of the Endangered Species Act, or the designated critical habitat of any species so listed.

(4) Biosolids which do not meet the Table 3 Pollutant Concentration Limits with respect to metals as defined in section 64.12 , of these regulations, and which are applied to land shall be subject to the Table 2 Cumulative Pollutant Loading Limits.

(5) Compliance with cumulative pollutant loading limits shall be documented by the permit Applicant. Documentation shall consist of either:

(a) a certification statement signed by the site owner, or the legal representative of the site owner, that the site has not received sludge application since January 1, 1986, or

(b) data quantifying loadings of cadmium, copper, lead, nickel and zinc which have occurred after January 1, 1986, and demonstrating that loadings of those metals to the site since that date do not exceed cumulative application limits for those parameters as defined in Table 2, and data quantifying loadings of arsenic, mercury, and selenium which have occurred after July 19, 1993, and demonstrating that loadings of those metals to the site since that date do not exceed cumulative application limits for those parameters as defined in Table 2.

B.Notification Requirements for Preparers and Appliers.

(1) Any person who prepares biosolids that will be applied by another to agricultural land or used by another for reclamation of disturbed land shall provide the following to the biosolids applier:

(a) written notification of the total nitrogen concentration, on a dry weight basis, of the biosolids; and

(b) notice of and necessary information to comply with the applicable requirements of these regulations.

(2) The biosolids applier shall provide written notice to the Division and the local health authority when biosolids are applied to agricultural land or used for reclamation of disturbed land. Such notice shall be provided prior to land application of biosolids by the preparer or the applier and shall occur at a minimum of one time per year. Notification shall include the following:

(a) the location, by either latitude and longitude or quarter-section, township, range, of each land application or reclamation use site;

(b) the approximate time period the biosolids will be applied to the site;

(c) the name, address, telephone number, and permit number (if appropriate) for the biosolids preparer; and

(d) the name, address, telephone number, and permit number (if appropriate) for the person who will land apply or use the biosolids for reclamation.

(3) Biosolids preparers shall ensure that the applicable requirements of these regulations are met when the biosolids are applied to agricultural land or used for reclamation of disturbed land.

(4) Any person who produces biosolids in Colorado, which biosolids are land applied to agricultural land or used for reclamation of disturbed land in another State, shall provide written notice to the permitting authority for the State in which the biosolids are proposed to be so used or land applied prior to commencement of such activities.

C.Application Near State Waters.

(1) No person shall apply biosolids for beneficial use on land located upgradient, and within one linear mile, of a point at which surface waters are diverted for use in a public water system, unless either:

(a) Runoff from within the application site does not drain into the body of water which is diverted, or

(b) A site operating plan is prepared, and submitted with the Letter of Intent for the Use and Distribution of Biosolids which describes measures which prevent runoff during any storm event of greater frequency than the 10 year 24-hour storm event from the application site into the body of water which is diverted.

(2) No person shall apply biosolids for beneficial use on land located:

(a) Upgradient and within 300 feet of a reservoir classified for Class I Recreational Use by the Water Quality Control Commission,

(b) Within 200 feet of any body of surface water, including intermittent streambeds when standing or running water is present in the streambed, unless application is made by either subsurface injection, or by surface application which is followed by immediate incorporation, or a site operating plan is prepared, and submitted with the Letter of Intent to Use or Distribute Biosolids which describes measures which prevent runoff from the application site into the body of water,

(c) Within 50 feet of any water body or perennial streambed, or any intermittent streambed when standing or running water is present in the streambed,

(d) Within 33 feet of any dry streambed. For purposes of this section land which, as the result of typical agricultural practice, is under cultivation shall not be considered to be a dry streambed regardless of whether it serves as a watercourse during significant precipitation events.

TABLE 5 - APPLICATION NEAR STATE WATERS

No application within 1 linear mile upgradient from a point at which surface water is diverted for use in a public water system, unless the requirements in section 64.15 (C)(1)(a) or (b) are met.

No application upgradient and within 300 feet of a reservoir classified for Class 1 Recreational Use by the Water Quality Control Commission (generally, lakes and streams frequently used for swimming, rafting, kayaking, tubing, windsurfing and water-skiing - activities where ingestion of small quantities of water is likely to occur).

Application Method	Incorporated or Injected	Surface
Any surface water channel including intermittent streambeds when water is present	50 Feet	200 Feet
Any surface water channel including intermittent streambeds when water is not present	33 Feet	33 Feet

Agricultural land under cultivation shall not be considered a dry streambed regardless of whether it serves as a watercourse during significant precipitation events.

(3) No person shall apply biosolids for beneficial use on land which is saturated, or on land where ponding is occurring.

(4) No person shall apply biosolids for beneficial use on land which is either:

(a) within 100 feet of a private domestic water supply well or within 300 feet of a community supply well when use is made to agricultural land, or

(b) within 300 feet of a private domestic water supply well or within 1,500 feet upgradient of a community supply well when use is made for reclamation of disturbed land.

D.Groundwater.

(1) No person shall apply biosolids for beneficial use on land which is underlain by groundwater where the annual high groundwater table is within five feet of the surface of the land unless conditions of 64.15D(2) are met. Determination of the annual high groundwater table shall be made as follows:

(a) Groundwater depth determinations based upon direct observation using piezometric tubes or other groundwater depth monitoring devices shall be the preferred method of groundwater depth determination. The Division may require installation of such devices in instances where other information which is developed does not conclusively demonstrate adequate depth to groundwater, alternately,

(b) U.S.D.A. Soil Survey maps of the application site, including depth to water table information, and/or

(c) Well completion records may be considered as documentation, either singly or in combination with other supporting documentation, in instances where surface topography, vegetation, or lack of seasonal ponding suggest that adequate depth to groundwater exists, and/or.

(d) Any other methods approved by the Division.

(2) If the annual high ground water table at any point under the land application site is potentially within five feet of the ground surface, a site operating plan must be prepared, and submitted with the Letter of Intent for the Use and Distribution of Biosolids, which describes how the land application of biosolids would be conducted in a manner that would prevent the discharge of pollutants to groundwater. The plan shall provide enough specifics so that the plan can be reviewed for adequacy. This plan must be approved by the Division through issuance of the Notice of Authorization.

E.Slopes and Application Requirements.

(1) No person shall apply biosolids to agricultural land on slopes in excess of 15 percent.

(2) Application of biosolids to agricultural land with slopes of less than 15 percent shall conform with the requirements stated in Table 6A.

TABLE 6A. - SLOPE AND APPLICATION REQUIREMENTS FOR AGRICULTURAL LAND

percent slope	less than six percent solids content	six percent or greater solids content
level to five percent slope	no limitation on application method except as otherwise specified within this section 64.16	no limitation on application method except as otherwise specified within this section 64.16
greater than five to nine percent slope	incorporation within 24 hours, subsurface injection or approved site operating plan	no limitation on application method except as otherwise specified within this section 64.16
greater than nine to fifteen percent slope	subsurface injection or approved site operating plan	surface application if vegetative cover is established or if uniform crop residue cover of greater than 60%,or approved site operating plan

(3) No person shall apply biosolids for reclamation on disturbed land which exhibits slopes in excess of 30 percent.

(4) Application of biosolids for reclamation of disturbed land with slopes of less than 30 percent shall conform with the requirements stated in Table 6B.

TABLE 6B. - SLOPE AND APPLICATION REQUIREMENTS FOR RECLAMATION

percent slope	less than six percent solids content	six percent or greater solids content
level to five percent slope	no limitation on application method except as otherwise specified within this section 64.16	no limitation on application method except as otherwise specified within this section 64.16
greater than five to nine percent slope	immediate incorporation, subsurface injection or approved site operating plan	no limitation on application method except as otherwise specified within this section 64.16
greater than nine to fifteen percent slope	subsurface injection or approved site operating plan	incorporation within 24 hours or approved site operating plan
greater than sixteen to thirty percent	application prohibited	incorporation within 24 hours or approved site operating plan

F.Application to Frozen, Ice-Covered, or Snow-Covered Ground.

(1) Application of biosolids to frozen, ice-covered, or snow-covered sites where the slope of the site exceeds six percent is prohibited.

(2) No person shall apply biosolids for beneficial use to frozen, ice-covered, or snow-covered land where the slope of such land is greater than three percent and is less than or equal to six percent unless one of the following requirements is met:

(a) there is 80 percent vegetative ground cover; or,

(b) approval has been obtained based upon a plan demonstrating adequate runoff containment measures.

G.Soils.

(1) No person shall apply biosolids for beneficial use on land cultivated in food crops where the soil exhibits a pH of less than 6.0 standard units.

(2) No person shall apply biosolids for beneficial use on land unless:

(a) for irrigated agricultural land, the depth of suitable soil is a minimum of three (3) feet, or

(b) for agricultural land cultivated in dryland crops, or for rangeland, the depth of suitable soil is a minimum of eighteen (18) inches, or

(c) for reclamation of disturbed land the depth of suitable soil is a minimum of twelve (12) inches.

(d) For the purposes of this paragraph 64.15(G)(2), the depth of suitable soil shall be defined as the distance beneath the level in the soil at which biosolids are placed to the level at which impermeable substrata are encountered. The Division shall approve the method of determining depth to suitable soil.

H.Nutrient Management.

(1) No person shall apply biosolids for beneficial use to agricultural land such that nitrogen application exceeds the agronomic rate for the crop or vegetation cultivated. Agronomic loading rates shall be determined in a manner that is acceptable to the Division and shall account for plant available nitrogen sources which may include biosolids, manures, fertilizers, irrigation water, residual soil nitrogen, and soil organic matter. The Division may require monitoring to determine background levels of nitrogen in irrigation water in instances where the soil percolation rate, groundwater depth and residual soil nitrogen level indicate a reasonable potential for excessive nitrogen transport to groundwater.

(2) No person shall apply biosolids for reclamation of disturbed land such that the nitrogen application exceeds the agronomic rate for the vegetation which is to be established, except that such application rate may be based upon an aggregate agronomic need representing the initial five years after application occurs or as justified in an operational plan that documents the application rate and process has been designed to prevent the discharge of pollutants to State Waters, and is approved by the Division.

(3) When, per paragraph (2) of this subsection, a nitrogen application rate is requested which is based on an aggregate agronomic requirement for the vegetation, the Division may specify additional siting and operational restrictions which are more stringent than those otherwise specified within this section 64.15, or additional monitoring requirements which are more stringent than those specified in section 64.16 of these regulations.

(4) The plant available nitrogen levels (lbs per dry ton) in biosolids shall be calculated as follows:

Biosolids PAN = (m) (Organic N) + (v) (NH4 -N) + NO3 -N

Where:

PAN = Plant Available Nitrogen (lbs per dry ton of biosolids)

m = Mineralization Factor v = Volatization Factor

Organic N = organic nitrogen in biosolids (%)

NH4 - N = Ammonia-nitrogen in biosolids(%)

NO3 - N = Nitrate-nitrogen in biosolids (%)

(5) No person shall apply biosolids for beneficial use to land, unless;

(a) For Soil pH greater than 6.5, the available phosphorus content of the soil does not exceed:

a. Sodium bicarbonate extraction - 80 ppm; or

b. AB-DTPA extraction - 40 ppm

(b) For Soil pH 6.5 or less, the available phosphorus content of the soil does not exceed:

a. Bray P1 extraction - 120 ppm; or

b. Mehlich 3 extraction - 200 ppm

(c) Where a phosphorus content limit in subsection (a) or (b), above, is exceeded, the Division may allow land application of biosolids where the potential for phosphorus movement off-site is minimized based on evaluation of site-specific conditions, management practices, application methods, and rates (e.g., in accordance with the Colorado phosphorus index).

(6) The Division may consider allowing land application of biosolids if appropriate erosion control measures are implemented (e.g., NRCS code 590 for Colorado).

I.Crop Restrictions.

(1) No person shall apply biosolids which are considered to be Class B with respect to pathogens, as defined in section 64.12 of these regulations, unless the following requirements are met:

(a) food crops with harvested parts that may touch the biosolids/soil mixture and which grow above the soil surface shall not be harvested for 14 months after application of biosolids, or

(b) food crops with harvested parts which grow below the soil surface shall not be harvested for 20 months after application of biosolids when the biosolids remain on the soil surface for four months or longer prior to incorporation into the soil, or

(c) food crops with harvested parts which grow below the soil surface shall not be harvested for 38 months after application of biosolids when the biosolids remain on the soil surface for less than four months prior to incorporation into the soil, or

(d) food crops, feed crops, and non-food crops shall not be harvested for 30 days after application of biosolids.

J.Access Restrictions.

(1) No person shall apply biosolids which are considered to be Class B with respect to pathogens, as defined in section 64.12 of these regulations, unless the following requirements are met:

(a) animals shall not be allowed to graze on the land for 30 days after application of biosolids. For the purposes of this section 64.15 , animals shall be defined as domesticated livestock whose products are consumed by humans.

(b) turf grown on land where biosolids is applied shall not be harvested for one year after application of the biosolids.

(c) public access to land with a high potential for public exposure shall be restricted for one year after application of biosolids, or

(d) public access to land with a low potential for public exposure shall be restricted for 30 days after application of biosolids.

5 CCR 1002-64.15

44 CR 17, September 10, 2021, effective 9/30/2021