Sludge Watch ==> Sewage Sludge Composts on the Roadside? Desert tortoise at risk

[maureen.reilly at sympatico.ca]

Sludgewatch Admin:

Southern California has had a problem managing its sewage sludge for a long 
time, now. That is why you hear so much about it.  More and more California 
counties are passing ever more stringent ordinances that limit the land 
application of these sludges.  There are sludge 'composting' 
facilities...some that never seem to meet the minumum requirements for 
composting to Class A under the Part 503 regs,.... and since these 
operations get their money up front front from tipping fees and no one 
really wants to pay for sewage sludge 'products' many of these sludge 
compost sites are full to overflowing with brown stuff no one wants.

More and more California sewage sludge is getting trucked to Arizona, where 
the regs are lighter, but the cost of gas to get it there is getting 
prohibitive.

So Caltrans (the California Roads folks) has stepped up and is talking about 
taking sewage sludge compost to use to landscape the areas around the roads. 
  This may mean that sludges will be wind whipped along the highways...It 
will also be a problem for flooding, since the sludges tend to be very high 
in phosphorus and some nitrogen, and even the excessive nutrients could 
cause major damage to desert ecologies.  The mold and fungus in the sludges 
could prove fatal to the endangered desert tortoise.  The sludges contain 
actinomycetes....which are related to desert tortoise deaths.

Many counties require a permit or other restriction for any use of sewage 
sludge ... whether it is Class B or Class A.  Caltrans needs to rethink the 
idea of sludge beside the road.
......................................................

BioCycle April 2006, Vol. 47, No. 4, p. 53

California Integrated Waste Management Board collaborates with local 
agencies, universities and the composting community to increase demand for 
quality compost.

Ava DeLara

WITH over 30 percent of its waste stream consisting of compostable organic 
materials, California is leading an aggressive campaign to find alternatives 
to their ending up in landfills. That explains why the California Integrated 
Waste Management Board (CIWMB) is pursuing various programs to reduce the 
amount of organic materials being landfilled in the state, while protecting 
public health and environmental safety. Organic material management 
facilities divert from the landfill and process roughly 8 million tons/year 
of organic material, while over 13 million tons/year, most suitable for 
composting, still go to landfills.

Composting has been a key focus of CIWMB for years, and the Board is always 
looking for opportunities to encourage the private sector and residential 
communities to become active in the effort to reduce, reuse and, recycle. 
Among the more recent initiatives, described in this article, are increasing 
compost use by CalTrans (the state transportation department), working with 
local enforcement agencies and composting facilities to minimize odor 
complaints, improving efficiency of water use in urban landscapes, and 
supporting development of emerging technologies that help divert valuable 
resources away from California's landfills (see sidebar on “Emerging 
Technologies”).

INCREASING COMPOST USE BY CALTRANS

State government agencies can have a significant impact on building markets 
for products made from recycled and composted materials. In the case of 
compost, the California Department of Transportation (Caltrans) represents 
one of the most lucrative governmental agency targets for widespread use.

In 2003/2004, CIWMB held meetings with Caltrans and the compost industry to 
determine the barriers to increased use of compost and mulch by Caltrans and 
how to overcome these barriers. As a result of these discussions, the CIWMB 
allocated $75,000 to fund the “Increasing Compost Use by Caltrans” contract 
in 2005. Participants in the contract include CIWMB, Caltrans, the 
University of California in Riverside Extension, the Association of Compost 
Producers (ACP), San Diego State University, Soil Control Laboratories, BFI, 
Inc., erosion control professionals, and many others.
Goals of the project include developing and promoting a Compost Use Index to 
help compost producers and users quickly identify products that will best 
satisfy their particular needs, reduce occasions of inappropriate use that 
can leave negative impressions and develop a “User Knowledge Base” index. 
Since compost users often need a specific type, or range, of compost 
products to satisfy specific soil requirements, this index matches various 
indexed product ranges with the frequency of use for specific defined 
applications. To make this truly useful and relevant, an updatable user 
knowledge base for various types of compost applications, by multiple users 
and diverse regions is required. This will be set up, funded and managed via 
a consortium of users. (The accompanying article in this section, “Compost 
Use for Erosion Control in California,” describes research projects done 
with CalTrans to test various compost feedstocks and product.)
As of November 2005, kickoff strategy meetings have been held and the first 
version of the Compost Use Index is nearing completion. Revision of the 
Caltrans compost specifications will immediately follow completion of the 
Compost Use Index. Additionally, the CIWMB will assist Caltrans in the 
development of a Compost Applications Best Practices Manual, and conduct 
workshops at Caltrans District offices in Sacramento, Oakland, Fresno, Los 
Angeles, and San Diego.
On May 25, 2005, the CIWMB and the Association of Compost Producers (ACP) 
implemented a demonstration project at the I-215/SR-134 interchange in 
Pasadena to showcase the beneficial use of compost and mulch products for 
landscape and erosion control. A “Certified Erosion Control” installer of 
Filtrexx International products sprayed composted mulch over patches of bare 
ground and into filter socks on a freeway hillside to prevent soil erosion, 
conserve water and reduce weed growth. The demonstration is part of an 
enhanced effort between Caltrans and the CIWMB to increase the use of 
recycled-content materials and products in the state's transportation 
system.

COMPREHENSIVE COMPOST ODOR  RESPONSE PROJECT

The increased use of compostable material processing in California requires 
a higher level of involvement by the CIWMB to address odor problems and 
other concerns. The CIWMB is working with the University of California in 
Riverside (UC Riverside) to develop tools for local enforcement agencies 
(LEAs) and operators for minimizing odor complaints from existing organic 
material management facilities. In addition, the work is intended to provide 
tools to local planners for evaluating the technical aspects of proposed 
facilities and for incorporating the appropriate operational and site 
provisions that should occur during the local approval process. These tools 
are critical to maintain the Board's authority over these facilities, ensure 
the viability of their future operations, promote operations with minimal 
environmental impacts, and provide LEAs and local planners with enforcement 
tools that mitigate environmental impacts of odors.
Details of the project include an assessment of odor problems through a 
survey of scientific and industry literature; review of facility records and 
discussions with CIWMB, LEA, academic, and industry sources; development of 
odor identification kits to assist LEAs in identifying characteristic odors 
associated with certain conditions (e.g., anaerobic, acidic, etc.) or 
feedstock types; research mitigation alternatives through laboratory 
investigation of the role of various parameters in odor formation, including 
aeration frequency, pH, additives, compost biofilter, odor neutralizing 
agents, and others; development of LEA and operator resource guides that 
include mitigation strategies for different types of odor occurrences; 
workshops to train LEAs on the resource guide and other materials; and 
development of a local government guide to assist local planners and 
decision makers in determining whether specific site design and operation 
plans adequately address odor mitigation.
The goal of this component is to provide local government with the tools to 
address potential problems with siting, design, and operations early in the 
planning process. This could be useful to a Local Task Force in their 
development of goals, policies, and procedures, which guide the county in 
their preparation of the Non-disposal Facility Element (NDFE).

SUSTAINABLE LANDSCAPE PROGRAMS

Assembly Bill 2717 (Laird, D-Santa Cruz) requires the California Urban Water 
Conservation Council to convene a stakeholder workgroup comprised of 
public/private agencies and associations to evaluate and recommend proposals 
to improve the efficiency of water use in new and existing urban irrigated 
landscapes in the state. CIWMB staff worked with StopWaste.org and the 
Association of Compost Producers to develop a Soil Assessment and Soil 
Management recommendation that was approved by the Task Force and requires a 
physical and chemical analysis of soils in new developments to improve water 
use efficiency and plant health. This recommendation may help increase the 
use of compost and mulch in urban landscapes.

For more information on the AB 2717 Landscape Task Force recommendations, 
visit:

www.cuwcc.org/landscape_task_force/AB2717draftreport110905.pdf.

A well-designed and maintained landscape can cost less to maintain in the 
long run by consuming fewer resources. StopWaste.org has developed 
landscaping guidelines to protect the San Francisco Bay watershed. The 
Bay-Friendly Landscaping Guidelines is a whole systems approach to the 
design, construction and maintenance of the landscape in order to support 
the integrity of one of California's most magnificent ecosystems, the San 
Francisco Bay watershed. In the Capitol, the CIWMB is working with the 
County of Sacramento Storm Water Management Program to revise the 
StopWaste.org guidelines into a “Sacramento Friendly” version.
The guide's basic landscape principles are to reduce waste and recycling 
materials; nurture healthy soils while reducing fertilizer use; conserve 
water, energy and topsoil; use integrated pest management to minimize 
chemical use; reduce storm water runoff; and create wildlife habitat. For 
more information on Bay Friendly Landscape Guidelines, visit their website, 
www.stopwaste.org/.

Ava DeLara is an Associate Governmental Program Analyst with the California 
Integrated Waste Management Board. She can be contacted via e-mail at: 
adelara at CIWMB.ca.gov.






Performance in construction and roadway projects

By Karin Grobe

Compost, an erosion control material that enhances soil and is made from 
readily available, inexpensive materials, is gaining ground as an accepted 
material for erosion control and roadside landscaping in California. 
Construction projects typically degrade and compact soil, causing breakdown 
of aggregates and loss of structure.

When tilled into the surface 6 inches, compost modifies the physical soil 
properties, improving water-holding ability and resistance to compaction. 
The microorganisms in compost aid in the formation of soil aggregates, the 
building blocks of good soil structure and tilth. Bacteria and fungi attach 
themselves to soil particles and bind them together, forming aggregate 
crumbs. Spaces in the aggregates allow water to percolate the soil and air 
to reach plant roots. When soil particles aggregate together, they are less 
likely to erode during rainstorms.

In clay soils compost reduces the bulk density and increases the porosity, 
thus improving the exchange of air and water through the soil. In sandy 
soils compost increases the water-holding capacity and soil aggregation. 
Availability of greenwaste compost products has stimulated research on how 
compost best can be used in typical landscaping and erosion control 
projects.

Roadside Landscaping
The California Department of Transportation (Caltrans), which develops 
specifications for roadside landscaping that are used by all government 
agencies, has added compost to the materials it specifies for erosion 
control.

Jack Broadbent, supervising landscape architect in Caltrans’ Office of 
Roadside Management, is taking a closer look at different ways to use 
compost. “We use native plants, but we are not planting them in native 
soil,” he says. The native topsoil often is removed from the site or 
degraded and compacted from site work. Rainwater runs off because it can’t 
penetrate the soil. Compost has proven effective for erosion control when 
incorporated into site soil at high rates.

“In one area the site soil was mainly decomposed granite—it was like a big 
granite sand pile,” says Broadbent. “We incorporated 24% greenwaste compost 
and found that it increased water infiltration and almost eliminated 
sediment production.”

Compost quality has emerged as an important consideration for Caltrans. 
Non-biodegradable contaminants can be a problem, as can weed seeds, which 
compete with seedlings that Caltrans is trying to establish.

Broadbent is working with the California Integrated Waste Management Board 
(CIWMB) to develop a compost classification system. The system will include 
compost-quality specifications that incorporate the Seal of Testing 
Assurance (STA) compost testing and information disclosure procedures. “STA 
testing puts everybody on the same page,” says Broadbent. “We’ll be able to 
tell our contractors what we want, and they’ll be able to determine if a 
given compost product meets the specs.” The STA program was developed by the 
US Composting Council (www.compostingcouncil.org).

Caltrans is also working with the CIWMB to develop a best practices manual 
for compost applications that will tie into the compost classification 
system and Caltrans specifications.

Broadbent works with University of California researchers to determine the 
most effective way to use compost in roadside landscaping projects.

Vic Claassen, a soil scientist with the UC Davis Department of Land, Air and 
Water Resources, is researching the viability of incorporating high volumes 
of compost into the site soil prior to planting. “I look at how undisturbed 
native soils work and try to figure out how to make degraded roadside soils 
function the same way,” he says. For plant establishment to succeed, soils 
must retain their plant cover, gradually accumulate nutrients, support 
microbial and mycorrhizal activity, allow for moisture infiltration, and 
hold onto rainwater.

Claassen completed a survey of compost products available in California in 
2002. In 2004 he evaluated nitrogen mineralization and release of six 
yardwaste compost products, two of which contained biosolids (Claassen and 
Carey 2004).

“The good news is that in the long run compost can greatly help regenerate 
barren soils,” he says. Compost works well in the physical sense, adding 
pore space and improving water-holding capacity. After a couple of years 
compost products generally release nitrogen at comparable rates to 
undisturbed native soils and are suitable for providing nitrogen for plant 
establishment on disturbed, low-nutrient soils.

“But in the short run it’s difficult to predict the nitrogen release of 
different compost products,” Claassen says. Nitrogen is essential for the 
establishment of landscape plants, but too much nitrogen can lead to weed 
invasion. Excess nitrogen can leach into waterways, upsetting the ecosystem. 
And too little nitrogen can slow growth of the erosion control plant 
materials.

Nitrogen availability of compost products is variable, depending on maturity 
and feedstocks. Composts that contain biosolids are fairly high in nitrogen 
and can release it too fast for native plant communities to absorb. 
Greenwaste compost products that are incorporated into the soil before they 
are fully cured typically have a nitrogen deficit and can compete with 
plants for scarce nitrogen, reducing initial plant establishment and growth.

“We can always add nitrogen if we know it’s going to be deficient,” says 
Claassen, “but we’ve got to know how much to add.”

Brent Hallock of the San Luis Obispo–based California Polytechnic State 
University’s Earth & Soil Sciences Department has done experiments in 
conjunction with Caltrans to test the potential effectiveness of compost in 
combination with other materials for establishing vegetation on disturbed 
roadside sites for short- and long-term erosion control.

One project completed at Cal Poly’s erosion control facility involved test 
boxes filled with topsoil compacted to 95% and set at a 2H:1V angle on a 
south-facing slope. A 0.25-inch application of compost was applied in 
combination with jute netting and crimped straw. Morro Bay compost 
(biosolids and yard trimmings) and Cal Poly compost (manure, straw, bedding, 
yard trimmings) were used in the experiments. Overall, treatments including 
compost reduced runoff and sediment without affecting water quality. Seeding 
establishment was best in the compost treatments in the sandy soil, 
indicating compost may have contributed fertility for plant growth.

Hallock says complex interactions between soil type, compost product, and 
vegetation type play into his results. “It’s not a linear relationship,” he 
says. “Some compost products did better on coarse-textured soil, and some 
did better on fine-textured soil.”

Erosion Control Research in Other States
Research in other states has yielded similar results. Researchers at Iowa 
State University cooperated with Department of Transportation officials to 
evaluate performance of compost as a surface mulch—called “compost 
blankets.” They found that 2-inch blankets were stable during intense 
simulated rainfall events and suppressed weeds. Runoff from compost-treated 
plots did not pose an increased environmental risk. Coarse composts were 
more effective than fine composts in controlling sheet erosion (Glanville, 
Richard, and Persyn 2003).

Washington State, recognizing that soil quality is directly related to water 
quality, includes soil quality and depth as best management practices in the 
Stormwater Management Manual for Western Washington. Developers are required 
to restore natural functions in disturbed soils by using organic amendments 
for erosion control. Soils must be amended to allow for moisture 
infiltration and retention (Guidelines and Resources Manual 2002, 
http://www.compostwashington.org/PDF/SOIL_MANUAL.pdf).

The Minnesota Department of Transportation has developed specifications for 
three grades of compost to be used in highway projects. For erosion control, 
compost can be applied in a 2-inch blanket or used as “grouting” to fill 
riprap voids. Specifications include applying compost with blower equipment 
to achieve a non-compacted layer. Compost can be blown into an 
8-inch-diameter photodegradable geotextile knitted tube to create a “log” 
that can be used for temporary sediment control around inlets and ditch 
checks (Minnesota DOT Standard Specifications for Construction, 2000 
Edition, http://www.dot.state.mn.us/tecsup/spec/2000/sp3861.pdf).

References
Claassen, V. and J. Carey. Spring 2004. “Regeneration of Nitrogen Fertility 
in Disturbed Soils Using Composts.” Compost Science and Utilization.

Glanville, T., T. Richard, and R. Persyn. May 2003. “Evaluating Performance 
of Compost Blankets.” BioCycle. www.biocycle.net.

Hallock, B., A. Power, S. Rein, and M. Scharff. 2004. Performance of Erosion 
Control Treatments and Native Vegetation on Reapplied Topsoil. IECA.

This article appeared in From the Ground Up, which is funded and 
administered by the City of San Jose Environmental Services Department. The 
purpose of From the Ground Up is to disseminate information on production 
and use of compost and mulch to landscape, agricultural, and horticultural 
professionals. Visit the Web site at www.urbancompost.org.