NPIMap

Organization Active NPI

Grass Valley Radiation Oncology

  • Radiation Oncology Physician
  • Grass Valley, CA
National Provider Identifier
1649895194
Registry record updated Apr 29, 2026
On this page

Key facts

NPPES NPI Registry
Primary specialty
Radiation Oncology PhysicianTaxonomy code 2085R0001X
Legal business name
GRASS VALLEY RADIATION ONCOLOGY
Practice address
300 Sierra College Dr Ste 150
Grass Valley, CA 95945-5083
Phone
(530) 802-6400
NPI assigned
Jun 10, 2020
Last updated
Apr 29, 2026By the provider in NPPES
Organization subpart
No

NPPES NPI Registry

Updated by the provider on Apr 29, 2026

Registry information is reported by the provider to CMS and is not verified. About this source

Authorized official

Name
Dr. Clayton B Hess, MDNPI 1235429507
Title
Owner
Phone
(678) 733-5626

Authorized official NPPES reports the official by name only. The link goes to the one practitioner connected to this organization with that name.

Specialties & licenses 1

Specialty (taxonomy)CodeLicenseStatePrimary
Radiation Oncology Physician 2085R0001X NU Primary

Addresses

Primary practice location

300 Sierra College Dr Ste 150
Grass Valley, CA 95945-5083

Mailing address

300 Sierra College Dr Ste 150
Grass Valley, CA 95945-5083
Phone (530) 802-6400

Other practice location 1

155 Glasson Way Bldg 3L-20
Grass Valley, CA 95945-5723
Phone (407) 788-1906 ext. 225

Medicare participation

Medicare enrollment files
Medicare fee-for-service enrollment
Enrolled in CA

Enrollment records 1

Enrollment IDStateProvider typePAC IDDetails
O20201002001867 CA Part B Supplier - Clinic/Group Practice 3779902192 Receives reassigned benefits from 9 practitioners
Practice locations: Grass Valley, CA

National Provider Directory

National Provider Directory

Locations

155 Glasson Way
Bldg 3
Grass Valley, CA 95945
Phone (530) 274-6600

155 Glasson Way
Bldg 3L20
Grass Valley, CA 95945
Phone 4077881906 ext. 225

300 Sierra College Dr
Ste 150
Grass Valley, CA 95945
Phone (530) 274-6600

Practitioners & affiliated clinicians

Practitioners 11

Individual providers connected to this organization through Medicare benefit reassignment, Care Compare group membership or National Provider Directory roles, and the practitioner matching its NPPES authorized official.

NPI Registry JSON

The complete NPPES record for this NPI in the NPI Registry API format.

{
    "created_epoch": "1591747200000",
    "enumeration_type": "NPI-2",
    "last_updated_epoch": "1777420800000",
    "number": "1649895194",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "300 SIERRA COLLEGE DR STE 150",
            "city": "GRASS VALLEY",
            "state": "CA",
            "postal_code": "959455083",
            "telephone_number": "530-802-6400",
            "fax_number": "530-267-6733"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "300 SIERRA COLLEGE DR STE 150",
            "city": "GRASS VALLEY",
            "state": "CA",
            "postal_code": "959455083",
            "telephone_number": "530-802-6400"
        }
    ],
    "practiceLocations": [
        {
            "address_1": "155 Glasson Way Bldg 3L-20",
            "address_purpose": "LOCATION",
            "city": "Grass Valley",
            "state": "CA",
            "postal_code": "959455723",
            "country_code": "US",
            "telephone_number": "407-788-1906 x225",
            "fax_number": "407-682-4844",
            "country_name": "United States",
            "address_type": "DOM"
        }
    ],
    "basic": {
        "organization_name": "GRASS VALLEY RADIATION ONCOLOGY",
        "organizational_subpart": "NO",
        "enumeration_date": "2020-06-10",
        "last_updated": "2026-04-29",
        "certification_date": "2026-04-29",
        "status": "A",
        "authorized_official_last_name": "HESS",
        "authorized_official_first_name": "CLAYTON",
        "authorized_official_middle_name": "B",
        "authorized_official_title_or_position": "OWNER",
        "authorized_official_telephone_number": "678-733-5626",
        "authorized_official_name_prefix": "Dr.",
        "authorized_official_credential": "MD"
    },
    "taxonomies": [
        {
            "code": "2085R0001X",
            "taxonomy_group": "",
            "desc": "Radiology, Radiation Oncology",
            "state": "NU",
            "license": null,
            "primary": true
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

Other providers in Grass Valley, CA

Sources for this page

  • NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Apr 29, 2026; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
  • Medicare enrollment (CMS PECOS): enrollments, PAC IDs and benefit reassignments.
  • National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.

Verify at the official NPI Registry.