Santa Maria Turns Two Environmentally Sensitive Liabilities Into an Innovative Community Asset

The City of Santa Maria won an Award for Excellence for this project in the Internal Administration category of the 2005 California Cities Helen Putnam Award for Excellence program. For more about the award program, visit

Located in Santa Barbara County, the City of Santa Maria is a fast growing, predominantly agricultural community with a population quickly approaching 90,000. Santa Maria provides a full range of municipal services to its residents, including solid waste collections and disposal.

The city owns and operates the Santa Maria Landfill, which serves residents and businesses throughout the Santa Maria Valley. Like all landfills built prior to the 1990s, the city’s landfill was not equipped with an impervious liner system (newer landfills require impervious liner systems to prevent groundwater contamination). A few years ago, groundwater contamination was confirmed under the landfill, and the Regional Water Quality Control Board issued a cleanup and abatement order. Failure to achieve compliance would result in having to prematurely close the landfill, and the city would incur costs of $27–$32 million, without the ongoing revenue to finance the project.

Furthermore, private property owners throughout the region faced the challenge of long-term treatment and containment of large volumes of oil-impacted soil as a result of the nearby Unocal Guadalupe oil field. Over many decades, hundreds of wells were drilled to extract millions of barrels of oil. Each well site had been affected by the storage of thousands of tons of well cuttings and oil-impacted soils, also known as drilling mud. The challenge was to facilitate the reclamation of thousands of acres of rangeland by excavating and containing large volumes of oil-impacted soils.

It’s a Twofer

City staff identified all possible opportunities to address these two challenges and decided to use the relatively large amount of oil-impacted soil to help seal off the unlined landfill, which would also address the long-term containment issue and provide for ongoing monitoring of the impacted soils. This resulted in the creation of the Non-Hazardous Impacted Soils (NHIS) Program. Because the oil-impacted soil contains more clay than oil, under current regulations it is not considered hazardous.

Every year, the city had been spending hundreds of thousands of dollars to mine clean soils from the Santa Maria River bed for daily landfill cover, landfill closure and liner construction. By using the oil-impacted soils instead, the city can redirect the clean soil material to other more beneficial projects, such as new school construction. Furthermore, the city charges companies for disposing of impacted soils at the landfill, which generates additional revenue — enough to finance all environmental remediation and other operational expenses.

During the same time period, Solid Waste Division staff implemented programs to use alternative systems to cover the daily deposits of refuse received at the landfill, further reducing the need to use clean soil, and saving time and hundreds of thousands of dollars. The division partnered with local building contractors to use construction and demolition debris, ground to a size suitable for using as fill material, to use instead of clean soil for the landfill. This saves landfill space and recycles the construction waste material.

Staff worked closely with regulatory agencies and the community to highlight the benefits and overcome possible negative public perception of using impacted soil on the aging landfill. The city also collaborated with major environmental consultants to provide innovative engineering design for the alternative closure, and major oil companies provided funding to construct state-of-the-art environmental impact control.

Because of this program, the city was able to avoid solid waste rate increases to customers for the past several years. Staff has successfully mitigated environmental impacts from the landfill to the groundwater beneath, while expediting closure of the unlined portion of the landfill by utilizing oil-impacted soil.

Revenues from the solid waste enterprise supplemented by resources from the NHIS program have enabled the city to build a new cell — a depression in the earth that is used as a unit for trash disposal. The new cell has a state-of-the-art landfill containment liner system, and this portion of the landfill won’t reach capacity until 2017.

The NHIS material serves as the foundation layer of the final cover system for the existing active portion of the landfill, and for daily and intermediate cover material in the lined expansion areas of the landfill, as well as road base. There have been no significant environmental impacts associated with the use of NHIS, so this program has turned into a win-win for everyone involved.

As one of the fastest growing communities in Santa Barbara County, Santa Maria’s residents have expressed great interest in more recreational facilities. The NHIS program has enabled the city to convert 68 acres of a previously closed portion of the landfill site to a state-of-art outdoor sports and recreation facility for youth.

The NHIS program is an innovative means of addressing two very important local environmental challenges, while streamlining operational efficiencies and generating revenue that help offset the need for rate increases. The program turned two environmentally sensitive liabilities into a community asset by:

  • Facilitating construction of a new state-of-the-art solid waste disposal cell for refuse generated in northern Santa Barbara County with a permitted capacity sufficient until the year 2017;
  • Accelerating the schedule to close the unlined portion of the landfill;
  • Aiding in the mitigation of groundwater contamination;
  • Facilitating a locally controlled cleanup of thousands of acres of privately owned rangeland;
  • Saving the city millions of dollars in capital expenses and allowing for the deferral of rate increases; and
  • Converting 68 acres of a closed landfill site to an outdoor sports and recreation venue.

Contact: John Zhao, solid waste/utilities engineer, City of Santa Maria; phone: (805) 925-0951, ext. 7245; e-mail:

This article appears in the July 2006 issue of Western City
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