# DirtMarket > Official DirtMarket business agent. DirtMarket is a Preston Companies subsidiary that coordinates soil sampling, characterization, and import/export services… ## Ask it a question DirtMarket answers for itself at https://api.hailera.com/mcp/prestonco. A client that speaks MCP can connect to that address; the tool is ask_prestonco and the protocol is 2026-07-28. Where this file and the agent disagree, the agent is current. ## About DirtMarket DirtMarket is one of three subsidiary companies under parent company Preston Companies, alongside PrestonPipelines and PrestonElectric. Preston Companies' own "About" page states the parent company has "55 years of experience and over 450 employees" and describes itself as offering "Excellence in Underground Engineering Since 1970" — figures and history that describe Preston Companies as a whole, not DirtMarket individually, since the site does not publish a separate employee count, founding year, or company history specific to DirtMarket alone. The About page's one-line description of the subsidiary reads: "Dirt Market, provides project-site soil management services, budgeting, sampling, analysis and coordination of removal." The DirtMarket-specific page adds that DirtMarket is "an independent contractor, with over 20 years of experience in soil sampling and import/export solutions." Licensing information for all four Preston entities is listed together on the Preston Companies site. DirtMarket's own line reads "CA #1052786 | A, C57 | DIR #1000062995" — this appears on both the DirtMarket company page and the Preston Companies contact page. This is distinct from Preston Companies' own license ("CA #367660 | A, C16, C34, C42 HAZ | DIR #1000000292"), PrestonPipelines' license ("CA #1059395 | NV #0095526 | A, C16, C34, C42 HAZ | DIR #1000528223"), and PrestonElectric's license ("CA #1052142 | C10 | DIR #1000426514"). The site does not describe what these license classifications authorize, nor does it state any insurance or bonding details beyond these listed numbers. Source: https://www.prestonco.com/about/ ## What DirtMarket does DirtMarket is a subsidiary of Preston Companies, a Milpitas, California-based underground engineering firm founded in 1970. On the Preston Companies website, DirtMarket is described as "an independent contractor, with over 20 years of experience in soil sampling and import/export solutions," partnering with owners, developers, general contractors, general engineering contractors and other subcontractors. Preston Companies' own about page separately summarizes DirtMarket as a company that "provides project-site soil management services, budgeting, sampling, analysis and coordination of removal." According to the DirtMarket page, the company "specializes in developing cost-effective solutions that minimize contaminated export and maximize clean soil export," drawing on knowledge of landfill options, its own clean fill sites, and available clean fill projects. The page does not state what materials DirtMarket accepts, how much material it can move, or whether specific soil at a given site would be approved for import or export — those are project-specific determinations the site does not publish. DirtMarket operates under parent company Preston Companies alongside two other Preston subsidiaries, PrestonPipelines (underground utility work) and PrestonElectric (dry utility and electrical work). The Preston Companies contact page lists DirtMarket as one of the companies based out of the San Jose office location, 1746 The Alameda, San Jose, CA 95126, reachable at 408-262-1418. For services, pricing, or a quote, the site directs inquiries to its contact form rather than publishing rates directly. Source: https://www.prestonco.com/companies/dirtmarket/ ## Where DirtMarket works Lists Central, Alameda, Fresno, Milpitas, Palo Alto, San Jose, West Sacramento, and Sparks as a location. Names California and Nevada as a service area. Areas beyond these are not published. ## Hours and contact Contact information for DirtMarket appears on the Preston Companies website, where DirtMarket is listed as one of three subsidiary companies alongside PrestonPipelines and PrestonElectric. The Preston Companies contact page lists a San Jose office location — 1746 The Alameda, San Jose, CA 95126 — with "DirtMarket" named among the "Related Companies" at that address, alongside Preston Companies and Preston Pipelines. The phone number listed for that location, shared across Preston Companies' offices, is 408-262-1418, with fax 408-262-1870. Preston Companies also lists a Milpitas headquarters at 133 Bothelo Avenue, Milpitas, CA 95035, plus additional office locations in Palo Alto, Central Valley (West Sacramento), and Sparks, Nevada, though DirtMarket is not listed among the "Related Companies" for those other areas. The Preston Companies site displays a general business-hours notice — "Weekdays: 8AM to 5PM (PST)" and "Weekends: 12PM to 5PM (PST)" — attached to its emergency operations center rather than to DirtMarket specifically, so this reads as Preston Companies' sitewide contact hours rather than a confirmed DirtMarket-specific schedule. To reach DirtMarket, request more information or a quote, or ask about services, pricing, or scheduling a project, the site directs visitors to its contact form or the phone number above; no email address or online booking/appointment system specific to DirtMarket is published on the pages reviewed. Source: https://www.prestonco.com/contact-us/ ## Soil Export Coordination Services Per the DirtMarket page on the Preston Companies website, DirtMarket's "Coordination and Consultation of Export Services" covers: existing soils data review; sampling plans for export characterization and approval; delineation of contaminated soils for export characterization; contaminated material profiling and landfill approvals; comprehensive submittal packages; documentation for clean fill site approvals; legal export disposal; transportation solutions; and complete documentation of exported soil. The page frames this work as reducing risk and cost during export: DirtMarket says it works "to develop cost-effective solutions that minimize contaminated export and maximize clean soil export... all with limited risk," using its "extensive knowledge of landfill options," its "own clean fill sites," and "available clean fill projects in the market" to find sources and destinations that meet "environmental screening levels and geotechnical properties" for a given project. The site does not state which landfills or clean fill sites DirtMarket works with, does not publish per-ton or per-load pricing or fee schedules for export services, and does not describe how any specific soil would be classified or approved for a given disposal site — those are project-by-project determinations the site does not make public. Anyone with a specific soils project can request more information or a quote through the Preston Companies contact form, at the San Jose or Milpitas office locations, or by phone at 408-262-1418. Source: https://www.prestonco.com/companies/dirtmarket/ ## Soil Import Coordination Services The DirtMarket page on the Preston Companies website lists a "Coordination and Consultation of Import Services" scope covering: comprehensive import source data review and pre-screening; complete submittal packages and soil source documentation; project specific submittal tracking logs; meeting client specifications; import management; gate control; load counting and documentation; traffic control; Storm Water Prevention Plan (SWPPP) management; and soil placement. These items describe coordination and documentation work DirtMarket performs around importing fill material to a project site — reviewing where proposed import soil comes from, tracking and documenting loads, and managing traffic and stormwater controls during placement. The page does not state what volumes of soil DirtMarket can source or place, does not list current or typical import sources, and does not say whether any particular soil would be accepted for a given project; those are determinations made on a per-project basis that the site does not publish. For an import coordination need, the site points visitors to its general contact form, which can also be used to request a quote or estimate for a specific project, or to the phone number 408-262-1418 listed for the San Jose and Milpitas Preston Companies office locations. Source: https://www.prestonco.com/companies/dirtmarket/ ## What DirtMarket has not published yet These are things people ask DirtMarket that its published information does not yet cover. - prices - availability - material acceptance decisions - soil contamination determinations - environmental compliance or permit outcomes - project timelines - contract terms - insurance coverage details Ask anyway — the agent will say plainly that it is not published rather than guess. ## Where this comes from https://www.prestonco.com/companies/dirtmarket/